Merge branch 'public_next' into master

src/CMakeLists.txt

@@ -150,6 +150,7 @@ set(SRB2_CORE_GAME_SOURCES
 	p_saveg.c
 	p_setup.c
 	p_sight.c
+	p_slopes.c
 	p_spec.c
 	p_telept.c
 	p_tick.c
@@ -162,6 +163,7 @@ set(SRB2_CORE_GAME_SOURCES
 	p_pspr.h
 	p_saveg.h
 	p_setup.h
+	p_slopes.h
 	p_spec.h
 	p_tick.h
 )

src/Makefile

@@ -454,6 +454,7 @@ OBJS:=$(i_main_o) \
 		$(OBJDIR)/p_telept.o \
 		$(OBJDIR)/p_tick.o   \
 		$(OBJDIR)/p_user.o   \
+		$(OBJDIR)/p_slopes.o \
 		$(OBJDIR)/tables.o   \
 		$(OBJDIR)/r_bsp.o    \
 		$(OBJDIR)/r_data.o   \

src/doomdef.h

@@ -439,6 +439,9 @@ extern const char *compdate, *comptime, *comprevision;
 ///	Fun experimental slope stuff!
 //#define SLOPENESS
 
+/// Kalaron/Eternity Engine slope code (SRB2CB ported)
+#define ESLOPE
+
 ///	Delete file while the game is running.
 ///	\note	EXTREMELY buggy, tends to crash game.
 //#define DELFILE

src/f_finale.c

@@ -982,6 +982,7 @@ static const char *credits[] = {
 	"",
 	"\1Programming",
 	"\1Assistance",
+	"\"chi.miru\"", // Red's secret weapon, the REAL reason slopes exist (also helped port drawing code from ZDoom)
 	"Andrew \"orospakr\" Clunis",
 	"Gregor \"Oogaland\" Dick",
 	"Julio \"Chaos Zero 64\" Guir",

src/m_fixed.c

@@ -119,8 +119,6 @@ fixed_t FixedHypot(fixed_t x, fixed_t y)
 	return FixedMul(ax, yx1); // |x|*((1 + (x/y)^2)^1/2)
 }
 
-#ifdef NEED_FIXED_VECTOR
-
 vector2_t *FV2_Load(vector2_t *vec, fixed_t x, fixed_t y)
 {
 	vec->x = x;
@@ -863,8 +861,6 @@ void FM_Scale(matrix_t *dest, fixed_t x, fixed_t y, fixed_t z)
 #undef M
 }
 
-#endif
-
 #ifdef M_TESTCASE
 //#define MULDIV_TEST
 #define SQRT_TEST

src/m_fixed.h

@@ -357,8 +357,6 @@ FUNCMATH FUNCINLINE static ATTRINLINE fixed_t FixedRound(fixed_t x)
 	return INT32_MAX;
 }
 
-#ifdef NEED_FIXED_VECTOR
-
 typedef struct
 {
 	fixed_t x;
@@ -437,6 +435,4 @@ void FM_MultMatrix(matrix_t *dest, const matrix_t *multme);
 void FM_Translate(matrix_t *dest, fixed_t x, fixed_t y, fixed_t z);
 void FM_Scale(matrix_t *dest, fixed_t x, fixed_t y, fixed_t z);
 
-#endif // defined NEED_FIXED_VECTOR
-
 #endif //m_fixed.h

src/p_enemy.c

@@ -5606,8 +5606,13 @@ void A_MixUp(mobj_t *actor)
 
 				P_SetThingPosition(players[i].mo);
 
+#ifdef ESLOPE
+				players[i].mo->floorz = P_GetFloorZ(players[i].mo, players[i].mo->subsector->sector, players[i].mo->x, players[i].mo->y, NULL);
+				players[i].mo->ceilingz = P_GetCeilingZ(players[i].mo, players[i].mo->subsector->sector, players[i].mo->x, players[i].mo->y, NULL);
+#else
 				players[i].mo->floorz = players[i].mo->subsector->sector->floorheight;
 				players[i].mo->ceilingz = players[i].mo->subsector->sector->ceilingheight;
+#endif
 
 				P_CheckPosition(players[i].mo, players[i].mo->x, players[i].mo->y);
 			}

src/p_floor.c

@@ -1174,12 +1174,15 @@ void T_SpikeSector(levelspecthink_t *spikes)
 
 		if (affectsec == spikes->sector) // Applied to an actual sector
 		{
+			fixed_t affectfloor = P_GetSpecialBottomZ(thing, affectsec, affectsec);
+			fixed_t affectceil = P_GetSpecialTopZ(thing, affectsec, affectsec);
+
 			if (affectsec->flags & SF_FLIPSPECIAL_FLOOR)
 			{
 				if (!(thing->eflags & MFE_VERTICALFLIP) && thing->momz > 0)
 					continue;
 
-				if (thing->z == affectsec->floorheight)
+				if (thing->z == affectfloor)
 					dothepain = true;
 			}
 
@@ -1188,18 +1191,20 @@ void T_SpikeSector(levelspecthink_t *spikes)
 				if ((thing->eflags & MFE_VERTICALFLIP) && thing->momz < 0)
 					continue;
 
-				if (thing->z + thing->height == affectsec->ceilingheight)
+				if (thing->z + thing->height == affectceil)
 					dothepain = true;
 			}
 		}
 		else
 		{
+			fixed_t affectfloor = P_GetSpecialBottomZ(thing, affectsec, spikes->sector);
+			fixed_t affectceil = P_GetSpecialTopZ(thing, affectsec, spikes->sector);
 			if (affectsec->flags & SF_FLIPSPECIAL_FLOOR)
 			{
 				if (!(thing->eflags & MFE_VERTICALFLIP) && thing->momz > 0)
 					continue;
 
-				if (thing->z == affectsec->ceilingheight)
+				if (thing->z == affectceil)
 					dothepain = true;
 			}
 
@@ -1208,7 +1213,7 @@ void T_SpikeSector(levelspecthink_t *spikes)
 				if ((thing->eflags & MFE_VERTICALFLIP) && thing->momz < 0)
 					continue;
 
-				if (thing->z + thing->height == affectsec->floorheight)
+				if (thing->z + thing->height == affectfloor)
 					dothepain = true;
 			}
 		}
@@ -2085,6 +2090,7 @@ void T_EachTimeThinker(levelspecthink_t *eachtime)
 	boolean FOFsector = false;
 	boolean inAndOut = false;
 	boolean floortouch = false;
+	fixed_t bottomheight, topheight;
 
 	for (i = 0; i < MAXPLAYERS; i++)
 	{
@@ -2149,10 +2155,13 @@ void T_EachTimeThinker(levelspecthink_t *eachtime)
 					if (players[j].mo->subsector->sector != targetsec)
 						continue;
 
-					if (players[j].mo->z > sec->ceilingheight)
+					topheight = P_GetSpecialTopZ(players[j].mo, sec, targetsec);
+					bottomheight = P_GetSpecialBottomZ(players[j].mo, sec, targetsec);
+
+					if (players[j].mo->z > topheight)
 						continue;
 
-					if (players[j].mo->z + players[j].mo->height < sec->floorheight)
+					if (players[j].mo->z + players[j].mo->height < bottomheight)
 						continue;
 
 					if (floortouch == true && P_IsObjectOnGroundIn(players[j].mo, targetsec))
@@ -2312,7 +2321,7 @@ void T_RaiseSector(levelspecthink_t *raise)
 			if (raise->vars[1] && !(thing->player->pflags & PF_STARTDASH))
 				continue;
 
-			if (!(thing->z == raise->sector->ceilingheight))
+			if (!(thing->z == P_GetSpecialTopZ(thing, raise->sector, sector)))
 				continue;
 
 			playeronme = true;

src/p_local.h

@@ -217,6 +217,23 @@ boolean P_RailThinker(mobj_t *mobj);
 void P_PushableThinker(mobj_t *mobj);
 void P_SceneryThinker(mobj_t *mobj);
 
+
+fixed_t P_MobjFloorZ(mobj_t *mobj, sector_t *sector, sector_t *boundsec, fixed_t x, fixed_t y, line_t *line, boolean lowest, boolean perfect);
+fixed_t P_MobjCeilingZ(mobj_t *mobj, sector_t *sector, sector_t *boundsec, fixed_t x, fixed_t y, line_t *line, boolean lowest, boolean perfect);
+#define P_GetFloorZ(mobj, sector, x, y, line) P_MobjFloorZ(mobj, sector, NULL, x, y, line, false, false)
+#define P_GetCeilingZ(mobj, sector, x, y, line) P_MobjCeilingZ(mobj, sector, NULL, x, y, line, true, false)
+#define P_GetFOFTopZ(mobj, sector, fof, x, y, line) P_MobjCeilingZ(mobj, sectors + fof->secnum, sector, x, y, line, false, false)
+#define P_GetFOFBottomZ(mobj, sector, fof, x, y, line) P_MobjFloorZ(mobj, sectors + fof->secnum, sector, x, y, line, true, false)
+#define P_GetSpecialBottomZ(mobj, src, bound) P_MobjFloorZ(mobj, src, bound, mobj->x, mobj->y, NULL, src != bound, true)
+#define P_GetSpecialTopZ(mobj, src, bound) P_MobjCeilingZ(mobj, src, bound, mobj->x, mobj->y, NULL, src == bound, true)
+
+fixed_t P_CameraFloorZ(camera_t *mobj, sector_t *sector, sector_t *boundsec, fixed_t x, fixed_t y, line_t *line, boolean lowest, boolean perfect);
+fixed_t P_CameraCeilingZ(camera_t *mobj, sector_t *sector, sector_t *boundsec, fixed_t x, fixed_t y, line_t *line, boolean lowest, boolean perfect);
+#define P_CameraGetFloorZ(mobj, sector, x, y, line) P_CameraFloorZ(mobj, sector, NULL, x, y, line, false, false)
+#define P_CameraGetCeilingZ(mobj, sector, x, y, line) P_CameraCeilingZ(mobj, sector, NULL, x, y, line, true, false)
+#define P_CameraGetFOFTopZ(mobj, sector, fof, x, y, line) P_CameraCeilingZ(mobj, sectors + fof->secnum, sector, x, y, line, false, false)
+#define P_CameraGetFOFBottomZ(mobj, sector, fof, x, y, line) P_CameraFloorZ(mobj, sectors + fof->secnum, sector, x, y, line, true, false)
+
 boolean P_InsideANonSolidFFloor(mobj_t *mobj, ffloor_t *rover);
 boolean P_CheckDeathPitCollide(mobj_t *mo);
 boolean P_CheckSolidLava(mobj_t *mo, ffloor_t *rover);
@@ -278,6 +295,11 @@ extern fixed_t tmfloorz;
 extern fixed_t tmceilingz;
 extern mobj_t *tmfloorthing, *tmhitthing, *tmthing;
 extern camera_t *mapcampointer;
+extern fixed_t tmx;
+extern fixed_t tmy;
+#ifdef ESLOPE
+extern pslope_t *tmfloorslope, *tmceilingslope;
+#endif
 
 /* cphipps 2004/08/30 */
 extern void P_MapStart(void);

src/p_map.c

@@ -27,6 +27,10 @@
 
 #include "r_splats.h"
 
+#ifdef ESLOPE
+#include "p_slopes.h"
+#endif
+
 #include "z_zone.h"
 
 #include "lua_hook.h"
@@ -34,8 +38,8 @@
 fixed_t tmbbox[4];
 mobj_t *tmthing;
 static INT32 tmflags;
-static fixed_t tmx;
-static fixed_t tmy;
+fixed_t tmx;
+fixed_t tmy;
 
 static precipmobj_t *tmprecipthing;
 static fixed_t preciptmbbox[4];
@@ -48,6 +52,9 @@ fixed_t tmfloorz, tmceilingz;
 static fixed_t tmdropoffz, tmdrpoffceilz; // drop-off floor/ceiling heights
 mobj_t *tmfloorthing; // the thing corresponding to tmfloorz or NULL if tmfloorz is from a sector
 mobj_t *tmhitthing; // the solid thing you bumped into (for collisions)
+#ifdef ESLOPE
+pslope_t *tmfloorslope, *tmceilingslope;
+#endif
 
 // keep track of the line that lowers the ceiling,
 // so missiles don't explode against sky hack walls
@@ -967,6 +974,9 @@ static boolean PIT_CheckThing(mobj_t *thing)
 				if (thing->z + thing->height > tmfloorz)
 				{
 					tmfloorz = thing->z + thing->height;
+#ifdef ESLOPE
+					tmfloorslope = NULL;
+#endif
 				}
 				return true;
 			}
@@ -985,6 +995,9 @@ static boolean PIT_CheckThing(mobj_t *thing)
 			else if (topz < tmceilingz && tmthing->z+tmthing->height <= thing->z+thing->height)
 			{
 				tmceilingz = topz;
+#ifdef ESLOPE
+				tmceilingslope = NULL;
+#endif
 				tmfloorthing = thing; // thing we may stand on
 			}
 		}
@@ -998,6 +1011,9 @@ static boolean PIT_CheckThing(mobj_t *thing)
 				if (thing->z < tmceilingz)
 				{
 					tmceilingz = thing->z;
+#ifdef ESLOPE
+					tmceilingslope = NULL;
+#endif
 				}
 				return true;
 			}
@@ -1015,6 +1031,9 @@ static boolean PIT_CheckThing(mobj_t *thing)
 			else if (topz > tmfloorz && tmthing->z >= thing->z)
 			{
 				tmfloorz = topz;
+#ifdef ESLOPE
+				tmfloorslope = NULL;
+#endif
 				tmfloorthing = thing; // thing we may stand on
 			}
 		}
@@ -1137,11 +1156,13 @@ static boolean PIT_CheckLine(line_t *ld)
 	{
 		tmceilingz = opentop;
 		ceilingline = ld;
+		tmceilingslope = opentopslope;
 	}
 
 	if (openbottom > tmfloorz)
 	{
 		tmfloorz = openbottom;
+		tmfloorslope = openbottomslope;
 	}
 
 	if (highceiling > tmdrpoffceilz)
@@ -1218,8 +1239,12 @@ boolean P_CheckPosition(mobj_t *thing, fixed_t x, fixed_t y)
 	// that contains the point.
 	// Any contacted lines the step closer together
 	// will adjust them.
-	tmfloorz = tmdropoffz = newsubsec->sector->floorheight;
-	tmceilingz = tmdrpoffceilz = newsubsec->sector->ceilingheight;
+	tmfloorz = tmdropoffz = P_GetFloorZ(thing, newsubsec->sector, x, y, NULL); //newsubsec->sector->floorheight;
+	tmceilingz = P_GetCeilingZ(thing, newsubsec->sector, x, y, NULL); //newsubsec->sector->ceilingheight;
+#ifdef ESLOPE
+	tmfloorslope = newsubsec->sector->f_slope;
+	tmceilingslope = newsubsec->sector->c_slope;
+#endif
 
 	// Check list of fake floors and see if tmfloorz/tmceilingz need to be altered.
 	if (newsubsec->sector->ffloors)
@@ -1233,32 +1258,43 @@ boolean P_CheckPosition(mobj_t *thing, fixed_t x, fixed_t y)
 			if (!(rover->flags & FF_EXISTS))
 				continue;
 
+			fixed_t topheight = P_GetFOFTopZ(thing, newsubsec->sector, rover, x, y, NULL);
+			fixed_t bottomheight = P_GetFOFBottomZ(thing, newsubsec->sector, rover, x, y, NULL);
+
 			if (rover->flags & FF_GOOWATER && !(thing->flags & MF_NOGRAVITY))
 			{
 				// If you're inside goowater and slowing down
 				fixed_t sinklevel = FixedMul(thing->info->height/6, thing->scale);
 				fixed_t minspeed = FixedMul(thing->info->height/9, thing->scale);
-				if (thing->z < *rover->topheight && *rover->bottomheight < thingtop
+				if (thing->z < topheight && bottomheight < thingtop
 				&& abs(thing->momz) < minspeed)
 				{
 					// Oh no! The object is stick in between the surface of the goo and sinklevel! help them out!
-					if (!(thing->eflags & MFE_VERTICALFLIP) && thing->z > *rover->topheight - sinklevel
+					if (!(thing->eflags & MFE_VERTICALFLIP) && thing->z > topheight - sinklevel
 					&& thing->momz >= 0 && thing->momz < (minspeed>>2))
 						thing->momz += minspeed>>2;
-					else if (thing->eflags & MFE_VERTICALFLIP && thingtop < *rover->bottomheight + sinklevel
+					else if (thing->eflags & MFE_VERTICALFLIP && thingtop < bottomheight + sinklevel
 					&& thing->momz <= 0 && thing->momz > -(minspeed>>2))
 						thing->momz -= minspeed>>2;
 
 					// Land on the top or the bottom, depending on gravity flip.
-					if (!(thing->eflags & MFE_VERTICALFLIP) && thing->z >= *rover->topheight - sinklevel && thing->momz <= 0)
+					if (!(thing->eflags & MFE_VERTICALFLIP) && thing->z >= topheight - sinklevel && thing->momz <= 0)
 					{
-						if (tmfloorz < *rover->topheight - sinklevel)
-							tmfloorz = *rover->topheight - sinklevel;
+						if (tmfloorz < topheight - sinklevel) {
+							tmfloorz = topheight - sinklevel;
+#ifdef ESLOPE
+							tmfloorslope = *rover->t_slope;
+#endif
+						}
 					}
-					else if (thing->eflags & MFE_VERTICALFLIP && thingtop <= *rover->bottomheight + sinklevel && thing->momz >= 0)
+					else if (thing->eflags & MFE_VERTICALFLIP && thingtop <= bottomheight + sinklevel && thing->momz >= 0)
 					{
-						if (tmceilingz > *rover->bottomheight + sinklevel)
-							tmceilingz = *rover->bottomheight + sinklevel;
+						if (tmceilingz > bottomheight + sinklevel) {
+							tmceilingz = bottomheight + sinklevel;
+#ifdef ESLOPE
+							tmceilingslope = *rover->b_slope;
+#endif
+						}
 					}
 				}
 				continue;
@@ -1275,30 +1311,40 @@ boolean P_CheckPosition(mobj_t *thing, fixed_t x, fixed_t y)
 
 			if (rover->flags & FF_QUICKSAND)
 			{
-				if (thing->z < *rover->topheight && *rover->bottomheight < thingtop)
+				if (thing->z < topheight && bottomheight < thingtop)
 				{
-					if (tmfloorz < thing->z)
+					if (tmfloorz < thing->z) {
 						tmfloorz = thing->z;
+#ifdef ESLOPE
+						tmfloorslope = NULL;
+#endif
+					}
 				}
 				// Quicksand blocks never change heights otherwise.
 				continue;
 			}
 
-			delta1 = thing->z - (*rover->bottomheight
-				+ ((*rover->topheight - *rover->bottomheight)/2));
-			delta2 = thingtop - (*rover->bottomheight
-				+ ((*rover->topheight - *rover->bottomheight)/2));
+			delta1 = thing->z - (bottomheight
+				+ ((topheight - bottomheight)/2));
+			delta2 = thingtop - (bottomheight
+				+ ((topheight - bottomheight)/2));
 
-			if (*rover->topheight > tmfloorz && abs(delta1) < abs(delta2)
+			if (topheight > tmfloorz && abs(delta1) < abs(delta2)
 				&& !(rover->flags & FF_REVERSEPLATFORM))
 			{
-				tmfloorz = tmdropoffz = *rover->topheight;
+				tmfloorz = tmdropoffz = topheight;
+#ifdef ESLOPE
+				tmfloorslope = *rover->t_slope;
+#endif
 			}
-			if (*rover->bottomheight < tmceilingz && abs(delta1) >= abs(delta2)
+			if (bottomheight < tmceilingz && abs(delta1) >= abs(delta2)
 				&& !(rover->flags & FF_PLATFORM)
 				&& !(thing->type == MT_SKIM && (rover->flags & FF_SWIMMABLE)))
 			{
-				tmceilingz = tmdrpoffceilz = *rover->bottomheight;
+				tmceilingz = tmdrpoffceilz = bottomheight;
+#ifdef ESLOPE
+				tmceilingslope = *rover->b_slope;
+#endif
 			}
 		}
 	}
@@ -1371,11 +1417,19 @@ boolean P_CheckPosition(mobj_t *thing, fixed_t x, fixed_t y)
 						delta1 = thing->z - (polybottom + ((polytop - polybottom)/2));
 						delta2 = thingtop - (polybottom + ((polytop - polybottom)/2));
 
-						if (polytop > tmfloorz && abs(delta1) < abs(delta2))
+						if (polytop > tmfloorz && abs(delta1) < abs(delta2)) {
 							tmfloorz = tmdropoffz = polytop;
+#ifdef ESLOPE
+							tmfloorslope = NULL;
+#endif
+						}
 
-						if (polybottom < tmceilingz && abs(delta1) >= abs(delta2))
+						if (polybottom < tmceilingz && abs(delta1) >= abs(delta2)) {
 							tmceilingz = tmdrpoffceilz = polybottom;
+#ifdef ESLOPE
+							tmceilingslope = NULL;
+#endif
+						}
 					}
 					plink = (polymaplink_t *)(plink->link.next);
 				}
@@ -1477,8 +1531,9 @@ boolean P_CheckCameraPosition(fixed_t x, fixed_t y, camera_t *thiscam)
 	// that contains the point.
 	// Any contacted lines the step closer together
 	// will adjust them.
-	tmfloorz = tmdropoffz = newsubsec->sector->floorheight;
-	tmceilingz = tmdrpoffceilz = newsubsec->sector->ceilingheight;
+	tmfloorz = tmdropoffz = P_CameraGetFloorZ(thiscam, newsubsec->sector, x, y, NULL);
+
+	tmceilingz = P_CameraGetCeilingZ(thiscam, newsubsec->sector, x, y, NULL);
 
 	// Cameras use the heightsec's heights rather then the actual sector heights.
 	// If you can see through it, why not move the camera through it too?
@@ -1507,17 +1562,20 @@ boolean P_CheckCameraPosition(fixed_t x, fixed_t y, camera_t *thiscam)
 			if (!(rover->flags & FF_BLOCKOTHERS) || !(rover->flags & FF_EXISTS) || !(rover->flags & FF_RENDERALL) || GETSECSPECIAL(rover->master->frontsector->special, 4) == 12)
 				continue;
 
-			delta1 = thiscam->z - (*rover->bottomheight
-				+ ((*rover->topheight - *rover->bottomheight)/2));
-			delta2 = thingtop - (*rover->bottomheight
-				+ ((*rover->topheight - *rover->bottomheight)/2));
-			if (*rover->topheight > tmfloorz && abs(delta1) < abs(delta2))
+			fixed_t topheight = P_CameraGetFOFTopZ(thiscam, newsubsec->sector, rover, x, y, NULL);
+			fixed_t bottomheight = P_CameraGetFOFBottomZ(thiscam, newsubsec->sector, rover, x, y, NULL);
+
+			delta1 = thiscam->z - (bottomheight
+				+ ((topheight - bottomheight)/2));
+			delta2 = thingtop - (bottomheight
+				+ ((topheight - bottomheight)/2));
+			if (topheight > tmfloorz && abs(delta1) < abs(delta2))
 			{
-				tmfloorz = tmdropoffz = *rover->topheight;
+				tmfloorz = tmdropoffz = topheight;
 			}
-			if (*rover->bottomheight < tmceilingz && abs(delta1) >= abs(delta2))
+			if (bottomheight < tmceilingz && abs(delta1) >= abs(delta2))
 			{
-				tmceilingz = tmdrpoffceilz = *rover->bottomheight;
+				tmceilingz = tmdrpoffceilz = bottomheight;
 			}
 		}
 	}
@@ -1712,8 +1770,8 @@ boolean P_TryCameraMove(fixed_t x, fixed_t y, camera_t *thiscam)
 	}
 	else
 	{
-		tmfloorz = thiscam->subsector->sector->floorheight;
-		tmceilingz = thiscam->subsector->sector->ceilingheight;
+		tmfloorz = P_CameraGetFloorZ(thiscam, thiscam->subsector->sector, x, y, NULL);
+		tmceilingz = P_CameraGetCeilingZ(thiscam, thiscam->subsector->sector, x, y, NULL);
 	}
 
 	// the move is ok,
@@ -1779,6 +1837,10 @@ boolean PIT_PushableMoved(mobj_t *thing)
 		mobj_t *oldthing = tmthing;
 		line_t *oldceilline = ceilingline;
 		line_t *oldblockline = blockingline;
+#ifdef ESLOPE
+		pslope_t *oldfslope = tmfloorslope;
+		pslope_t *oldcslope = tmceilingslope;
+#endif
 
 		// Move the player
 		P_TryMove(thing, thing->x+stand->momx, thing->y+stand->momy, true);
@@ -1791,6 +1853,10 @@ boolean PIT_PushableMoved(mobj_t *thing)
 		P_SetTarget(&tmthing, oldthing);
 		ceilingline = oldceilline;
 		blockingline = oldblockline;
+#ifdef ESLOPE
+		tmfloorslope = oldfslope;
+		tmceilingslope = oldcslope;
+#endif
 		thing->momz = stand->momz;
 	}
 	else
@@ -1812,6 +1878,9 @@ boolean P_TryMove(mobj_t *thing, fixed_t x, fixed_t y, boolean allowdropoff)
 	fixed_t tryy = thing->y;
 	fixed_t radius = thing->radius;
 	fixed_t thingtop = thing->z + thing->height;
+#ifdef ESLOPE
+	fixed_t startingonground = P_IsObjectOnGround(thing);
+#endif
 	floatok = false;
 
 	if (radius < MAXRADIUS/2)
@@ -1900,13 +1969,23 @@ boolean P_TryMove(mobj_t *thing, fixed_t x, fixed_t y, boolean allowdropoff)
 				{
 					if (thingtop == thing->ceilingz && tmceilingz > thingtop && tmceilingz - thingtop <= maxstep)
 					{
-						thing->z = tmceilingz - thing->height;
+						thing->z = (thing->ceilingz = thingtop = tmceilingz) - thing->height;
+						thing->eflags |= MFE_JUSTSTEPPEDDOWN;
+					}
+					else if (tmceilingz < thingtop && thingtop - tmceilingz <= maxstep)
+					{
+						thing->z = (thing->ceilingz = thingtop = tmceilingz) - thing->height;
 						thing->eflags |= MFE_JUSTSTEPPEDDOWN;
 					}
 				}
 				else if (thing->z == thing->floorz && tmfloorz < thing->z && thing->z - tmfloorz <= maxstep)
 				{
-					thing->z = tmfloorz;
+					thing->z = thing->floorz = tmfloorz;
+					thing->eflags |= MFE_JUSTSTEPPEDDOWN;
+				}
+				else if (tmfloorz > thing->z && tmfloorz - thing->z <= maxstep)
+				{
+					thing->z = thing->floorz = tmfloorz;
 					thing->eflags |= MFE_JUSTSTEPPEDDOWN;
 				}
 			}
@@ -1977,6 +2056,25 @@ boolean P_TryMove(mobj_t *thing, fixed_t x, fixed_t y, boolean allowdropoff)
 
 	thing->floorz = tmfloorz;
 	thing->ceilingz = tmceilingz;
+
+#ifdef ESLOPE
+	// Assign thing's standingslope if needed
+	if (thing->z <= tmfloorz && !(thing->eflags & MFE_VERTICALFLIP)) {
+		if (!startingonground && tmfloorslope)
+			P_HandleSlopeLanding(thing, tmfloorslope);
+
+		if (thing->momz <= 0)
+			thing->standingslope = tmfloorslope;
+	}
+	else if (thing->z+thing->height >= tmceilingz && (thing->eflags & MFE_VERTICALFLIP)) {
+		if (!startingonground && tmceilingslope)
+			P_HandleSlopeLanding(thing, tmceilingslope);
+
+		if (thing->momz >= 0)
+			thing->standingslope = tmceilingslope;
+	}
+#endif
+
 	thing->x = x;
 	thing->y = y;
 
@@ -1992,6 +2090,7 @@ boolean P_TryMove(mobj_t *thing, fixed_t x, fixed_t y, boolean allowdropoff)
 boolean P_SceneryTryMove(mobj_t *thing, fixed_t x, fixed_t y)
 {
 	fixed_t tryx, tryy;
+
 	tryx = thing->x;
 	tryy = thing->y;
 	do {
@@ -2314,15 +2413,25 @@ static boolean P_IsClimbingValid(player_t *player, angle_t angle)
 {
 	fixed_t platx, platy;
 	subsector_t *glidesector;
+	fixed_t floorz, ceilingz;
 
 	platx = P_ReturnThrustX(player->mo, angle, player->mo->radius + FixedMul(8*FRACUNIT, player->mo->scale));
 	platy = P_ReturnThrustY(player->mo, angle, player->mo->radius + FixedMul(8*FRACUNIT, player->mo->scale));
 
 	glidesector = R_PointInSubsector(player->mo->x + platx, player->mo->y + platy);
 
+#ifdef ESLOPE
+	floorz = glidesector->sector->f_slope ? P_GetZAt(glidesector->sector->f_slope, player->mo->x, player->mo->y) : glidesector->sector->floorheight;
+	ceilingz = glidesector->sector->c_slope ? P_GetZAt(glidesector->sector->c_slope, player->mo->x, player->mo->y) : glidesector->sector->ceilingheight;
+#else
+	floorz = glidesector->sector->floorheight;
+	ceilingz = glidesector->sector->ceilingheight;
+#endif
+
 	if (glidesector->sector != player->mo->subsector->sector)
 	{
 		boolean floorclimb = false;
+		fixed_t topheight, bottomheight;
 
 		if (glidesector->sector->ffloors)
 		{
@@ -2332,34 +2441,44 @@ static boolean P_IsClimbingValid(player_t *player, angle_t angle)
 				if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER))
 					continue;
 
+				topheight = *rover->topheight;
+				bottomheight = *rover->bottomheight;
+
+#ifdef ESLOPE
+				if (*rover->t_slope)
+					topheight = P_GetZAt(*rover->t_slope, player->mo->x, player->mo->y);
+				if (*rover->b_slope)
+					bottomheight = P_GetZAt(*rover->b_slope, player->mo->x, player->mo->y);
+#endif
+
 				floorclimb = true;
 
 				if (player->mo->eflags & MFE_VERTICALFLIP)
 				{
-					if ((*rover->topheight < player->mo->z + player->mo->height) && ((player->mo->z + player->mo->height + player->mo->momz) < *rover->topheight))
+					if ((topheight < player->mo->z + player->mo->height) && ((player->mo->z + player->mo->height + player->mo->momz) < topheight))
 					{
 						floorclimb = true;
 					}
-					if (*rover->topheight < player->mo->z) // Waaaay below the ledge.
+					if (topheight < player->mo->z) // Waaaay below the ledge.
 					{
 						floorclimb = false;
 					}
-					if (*rover->bottomheight > player->mo->z + player->mo->height - FixedMul(16*FRACUNIT,player->mo->scale))
+					if (bottomheight > player->mo->z + player->mo->height - FixedMul(16*FRACUNIT,player->mo->scale))
 					{
 						floorclimb = false;
 					}
 				}
 				else
 				{
-					if ((*rover->bottomheight > player->mo->z) && ((player->mo->z - player->mo->momz) > *rover->bottomheight))
+					if ((bottomheight > player->mo->z) && ((player->mo->z - player->mo->momz) > bottomheight))
 					{
 						floorclimb = true;
 					}
-					if (*rover->bottomheight > player->mo->z + player->mo->height) // Waaaay below the ledge.
+					if (bottomheight > player->mo->z + player->mo->height) // Waaaay below the ledge.
 					{
 						floorclimb = false;
 					}
-					if (*rover->topheight < player->mo->z + FixedMul(16*FRACUNIT,player->mo->scale))
+					if (topheight < player->mo->z + FixedMul(16*FRACUNIT,player->mo->scale))
 					{
 						floorclimb = false;
 					}
@@ -2372,30 +2491,30 @@ static boolean P_IsClimbingValid(player_t *player, angle_t angle)
 
 		if (player->mo->eflags & MFE_VERTICALFLIP)
 		{
-			if ((glidesector->sector->floorheight <= player->mo->z + player->mo->height)
-				&& ((player->mo->z + player->mo->height - player->mo->momz) <= glidesector->sector->floorheight))
+			if ((floorz <= player->mo->z + player->mo->height)
+				&& ((player->mo->z + player->mo->height - player->mo->momz) <= floorz))
 				floorclimb = true;
 
-			if ((glidesector->sector->floorheight > player->mo->z)
+			if ((floorz > player->mo->z)
 				&& glidesector->sector->floorpic == skyflatnum)
 				return false;
 
-			if ((player->mo->z + player->mo->height - FixedMul(16*FRACUNIT,player->mo->scale) > glidesector->sector->ceilingheight)
-				|| (player->mo->z + player->mo->height <= glidesector->sector->floorheight))
+			if ((player->mo->z + player->mo->height - FixedMul(16*FRACUNIT,player->mo->scale) > ceilingz)
+				|| (player->mo->z + player->mo->height <= floorz))
 				floorclimb = true;
 		}
 		else
 		{
-			if ((glidesector->sector->ceilingheight >= player->mo->z)
-				&& ((player->mo->z - player->mo->momz) >= glidesector->sector->ceilingheight))
+			if ((ceilingz >= player->mo->z)
+				&& ((player->mo->z - player->mo->momz) >= ceilingz))
 				floorclimb = true;
 
-			if ((glidesector->sector->ceilingheight < player->mo->z+player->mo->height)
+			if ((ceilingz < player->mo->z+player->mo->height)
 				&& glidesector->sector->ceilingpic == skyflatnum)
 				return false;
 
-			if ((player->mo->z + FixedMul(16*FRACUNIT,player->mo->scale) < glidesector->sector->floorheight)
-				|| (player->mo->z >= glidesector->sector->ceilingheight))
+			if ((player->mo->z + FixedMul(16*FRACUNIT,player->mo->scale) < ceilingz)
+				|| (player->mo->z >= ceilingz))
 				floorclimb = true;
 		}
 
@@ -2467,6 +2586,7 @@ isblocking:
 		line_t *checkline = li;
 		sector_t *checksector;
 		ffloor_t *rover;
+		fixed_t topheight, bottomheight;
 		boolean fofline = false;
 		INT32 side = P_PointOnLineSide(slidemo->x, slidemo->y, li);
 
@@ -2482,13 +2602,23 @@ isblocking:
 				if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER) || (rover->flags & FF_BUSTUP))
 					continue;
 
-				if (*rover->topheight < slidemo->z)
+				topheight = *rover->topheight;
+				bottomheight = *rover->bottomheight;
+
+#ifdef ESLOPE
+				if (*rover->t_slope)
+					topheight = P_GetZAt(*rover->t_slope, slidemo->x, slidemo->y);
+				if (*rover->b_slope)
+					bottomheight = P_GetZAt(*rover->b_slope, slidemo->x, slidemo->y);
+#endif
+
+				if (topheight < slidemo->z)
 					continue;
 
-				if (*rover->bottomheight > slidemo->z + slidemo->height)
+				if (bottomheight > slidemo->z + slidemo->height)
 					continue;
 
-				// Got this far, so I guess it's climbable.
+				// Got this far, so I guess it's climbable. // TODO: Climbing check, also, better method to do this?
 				if (rover->master->flags & ML_TFERLINE)
 				{
 					size_t linenum = li-checksector->lines[0];
@@ -3108,6 +3238,7 @@ static boolean PIT_ChangeSector(mobj_t *thing, boolean realcrush)
 		if (thing->subsector->sector->ffloors && (realcrush || thing->flags & MF_PUSHABLE))
 		{
 			ffloor_t *rover;
+			fixed_t topheight, bottomheight;
 			fixed_t delta1, delta2;
 			INT32 thingtop = thing->z + thing->height;
 
@@ -3117,9 +3248,19 @@ static boolean PIT_ChangeSector(mobj_t *thing, boolean realcrush)
 				|| ((rover->flags & FF_BLOCKOTHERS) && !thing->player)) || !(rover->flags & FF_EXISTS))
 					continue;
 
-				delta1 = thing->z - (*rover->bottomheight + *rover->topheight)/2;
-				delta2 = thingtop - (*rover->bottomheight + *rover->topheight)/2;
-				if (*rover->bottomheight <= thing->ceilingz && abs(delta1) >= abs(delta2))
+				topheight = *rover->topheight;
+				bottomheight = *rover->bottomheight;
+
+/*#ifdef ESLOPE
+				if (rover->t_slope)
+					topheight = P_GetZAt(rover->t_slope, thing->x, thing->y);
+				if (rover->b_slope)
+					bottomheight = P_GetZAt(rover->b_slope, thing->x, thing->y);
+#endif*/
+
+				delta1 = thing->z - (bottomheight + topheight)/2;
+				delta2 = thingtop - (bottomheight + topheight)/2;
+				if (bottomheight <= thing->ceilingz && abs(delta1) >= abs(delta2))
 				{
 					if (thing->flags & MF_PUSHABLE)
 					{
@@ -3790,7 +3931,7 @@ void P_MapEnd(void)
 }
 
 // P_FloorzAtPos
-// Returns the floorz of the XYZ position
+// Returns the floorz of the XYZ position // TODO: Need ceilingpos function too
 // Tails 05-26-2003
 fixed_t P_FloorzAtPos(fixed_t x, fixed_t y, fixed_t z, fixed_t height)
 {
@@ -3811,9 +3952,19 @@ fixed_t P_FloorzAtPos(fixed_t x, fixed_t y, fixed_t z, fixed_t height)
 			if ((!(rover->flags & FF_SOLID || rover->flags & FF_QUICKSAND) || (rover->flags & FF_SWIMMABLE)))
 				continue;
 
+			fixed_t topheight = *rover->topheight;
+			fixed_t bottomheight = *rover->bottomheight;
+
+#ifdef ESLOPE
+			if (*rover->t_slope)
+				topheight = P_GetZAt(*rover->t_slope, x, y);
+			if (*rover->b_slope)
+				bottomheight = P_GetZAt(*rover->b_slope, x, y);
+#endif
+
 			if (rover->flags & FF_QUICKSAND)
 			{
-				if (z < *rover->topheight && *rover->bottomheight < thingtop)
+				if (z < topheight && bottomheight < thingtop)
 				{
 					if (floorz < z)
 						floorz = z;
@@ -3821,10 +3972,10 @@ fixed_t P_FloorzAtPos(fixed_t x, fixed_t y, fixed_t z, fixed_t height)
 				continue;
 			}
 
-			delta1 = z - (*rover->bottomheight + ((*rover->topheight - *rover->bottomheight)/2));
-			delta2 = thingtop - (*rover->bottomheight + ((*rover->topheight - *rover->bottomheight)/2));
-			if (*rover->topheight > floorz && abs(delta1) < abs(delta2))
-				floorz = *rover->topheight;
+			delta1 = z - (bottomheight + ((topheight - bottomheight)/2));
+			delta2 = thingtop - (bottomheight + ((topheight - bottomheight)/2));
+			if (topheight > floorz && abs(delta1) < abs(delta2))
+				floorz = topheight;
 		}
 	}
 

src/p_maputl.c

@@ -322,6 +322,9 @@ fixed_t P_InterceptVector(divline_t *v2, divline_t *v1)
 // OPTIMIZE: keep this precalculated
 //
 fixed_t opentop, openbottom, openrange, lowfloor, highceiling;
+#ifdef ESLOPE
+pslope_t *opentopslope, *openbottomslope;
+#endif
 
 // P_CameraLineOpening
 // P_LineOpening, but for camera
@@ -348,31 +351,56 @@ void P_CameraLineOpening(line_t *linedef)
 	{
 		frontfloor = sectors[front->camsec].floorheight;
 		frontceiling = sectors[front->camsec].ceilingheight;
+#ifdef ESLOPE
+		if (sectors[front->camsec].f_slope) // SRB2CBTODO: ESLOPE (sectors[front->heightsec].f_slope)
+			frontfloor = P_GetZAt(sectors[front->camsec].f_slope, camera.x, camera.y);
+		if (sectors[front->camsec].c_slope)
+			frontceiling = P_GetZAt(sectors[front->camsec].c_slope, camera.x, camera.y);
+#endif
+
 	}
 	else if (front->heightsec >= 0)
 	{
 		frontfloor = sectors[front->heightsec].floorheight;
 		frontceiling = sectors[front->heightsec].ceilingheight;
+#ifdef ESLOPE
+		if (sectors[front->heightsec].f_slope) // SRB2CBTODO: ESLOPE (sectors[front->heightsec].f_slope)
+			frontfloor = P_GetZAt(sectors[front->heightsec].f_slope, camera.x, camera.y);
+		if (sectors[front->heightsec].c_slope)
+			frontceiling = P_GetZAt(sectors[front->heightsec].c_slope, camera.x, camera.y);
+#endif
 	}
 	else
 	{
-		frontfloor = front->floorheight;
-		frontceiling = front->ceilingheight;
+		frontfloor = P_CameraGetFloorZ(mapcampointer, front, tmx, tmy, linedef);
+		frontceiling = P_CameraGetCeilingZ(mapcampointer, front, tmx, tmy, linedef);
 	}
 	if (back->camsec >= 0)
 	{
 		backfloor = sectors[back->camsec].floorheight;
 		backceiling = sectors[back->camsec].ceilingheight;
+#ifdef ESLOPE
+		if (sectors[back->camsec].f_slope) // SRB2CBTODO: ESLOPE (sectors[front->heightsec].f_slope)
+			frontfloor = P_GetZAt(sectors[back->camsec].f_slope, camera.x, camera.y);
+		if (sectors[back->camsec].c_slope)
+			frontceiling = P_GetZAt(sectors[back->camsec].c_slope, camera.x, camera.y);
+#endif
 	}
 	else if (back->heightsec >= 0)
 	{
 		backfloor = sectors[back->heightsec].floorheight;
 		backceiling = sectors[back->heightsec].ceilingheight;
+#ifdef ESLOPE
+		if (sectors[back->heightsec].f_slope) // SRB2CBTODO: ESLOPE (sectors[front->heightsec].f_slope)
+			frontfloor = P_GetZAt(sectors[back->heightsec].f_slope, camera.x, camera.y);
+		if (sectors[back->heightsec].c_slope)
+			frontceiling = P_GetZAt(sectors[back->heightsec].c_slope, camera.x, camera.y);
+#endif
 	}
 	else
 	{
-		backfloor = back->floorheight;
-		backceiling = back->ceilingheight;
+		backfloor = P_CameraGetFloorZ(mapcampointer, back, tmx, tmy, linedef);
+		backceiling = P_CameraGetCeilingZ(mapcampointer, back, tmx, tmy, linedef);
 	}
 
 	{
@@ -417,17 +445,20 @@ void P_CameraLineOpening(line_t *linedef)
 					if (!(rover->flags & FF_BLOCKOTHERS) || !(rover->flags & FF_RENDERALL) || !(rover->flags & FF_EXISTS) || GETSECSPECIAL(rover->master->frontsector->special, 4) == 12)
 						continue;
 
-					delta1 = abs(mapcampointer->z - (*rover->bottomheight + ((*rover->topheight - *rover->bottomheight)/2)));
-					delta2 = abs(thingtop - (*rover->bottomheight + ((*rover->topheight - *rover->bottomheight)/2)));
-					if (*rover->bottomheight < lowestceiling && delta1 >= delta2)
-						lowestceiling = *rover->bottomheight;
-					else if (*rover->bottomheight < highestceiling && delta1 >= delta2)
-						highestceiling = *rover->bottomheight;
+					fixed_t topheight = P_CameraGetFOFTopZ(mapcampointer, front, rover, tmx, tmy, linedef);
+					fixed_t bottomheight = P_CameraGetFOFBottomZ(mapcampointer, front, rover, tmx, tmy, linedef);
 
-					if (*rover->topheight > highestfloor && delta1 < delta2)
-						highestfloor = *rover->topheight;
-					else if (*rover->topheight > lowestfloor && delta1 < delta2)
-						lowestfloor = *rover->topheight;
+					delta1 = abs(mapcampointer->z - (bottomheight + ((topheight - bottomheight)/2)));
+					delta2 = abs(thingtop - (bottomheight + ((topheight - bottomheight)/2)));
+					if (bottomheight < lowestceiling && delta1 >= delta2)
+						lowestceiling = bottomheight;
+					else if (bottomheight < highestceiling && delta1 >= delta2)
+						highestceiling = bottomheight;
+
+					if (topheight > highestfloor && delta1 < delta2)
+						highestfloor = topheight;
+					else if (topheight > lowestfloor && delta1 < delta2)
+						lowestfloor = topheight;
 				}
 
 			// Check for backsectors fake floors
@@ -437,17 +468,20 @@ void P_CameraLineOpening(line_t *linedef)
 					if (!(rover->flags & FF_BLOCKOTHERS) || !(rover->flags & FF_RENDERALL) || !(rover->flags & FF_EXISTS) || GETSECSPECIAL(rover->master->frontsector->special, 4) == 12)
 						continue;
 
-					delta1 = abs(mapcampointer->z - (*rover->bottomheight + ((*rover->topheight - *rover->bottomheight)/2)));
-					delta2 = abs(thingtop - (*rover->bottomheight + ((*rover->topheight - *rover->bottomheight)/2)));
-					if (*rover->bottomheight < lowestceiling && delta1 >= delta2)
-						lowestceiling = *rover->bottomheight;
-					else if (*rover->bottomheight < highestceiling && delta1 >= delta2)
-						highestceiling = *rover->bottomheight;
+					fixed_t topheight = P_CameraGetFOFTopZ(mapcampointer, back, rover, tmx, tmy, linedef);
+					fixed_t bottomheight = P_CameraGetFOFBottomZ(mapcampointer, back, rover, tmx, tmy, linedef);
 
-					if (*rover->topheight > highestfloor && delta1 < delta2)
-						highestfloor = *rover->topheight;
-					else if (*rover->topheight > lowestfloor && delta1 < delta2)
-						lowestfloor = *rover->topheight;
+					delta1 = abs(mapcampointer->z - (bottomheight + ((topheight - bottomheight)/2)));
+					delta2 = abs(thingtop - (bottomheight + ((topheight - bottomheight)/2)));
+					if (bottomheight < lowestceiling && delta1 >= delta2)
+						lowestceiling = bottomheight;
+					else if (bottomheight < highestceiling && delta1 >= delta2)
+						highestceiling = bottomheight;
+
+					if (topheight > highestfloor && delta1 < delta2)
+						highestfloor = topheight;
+					else if (topheight > lowestfloor && delta1 < delta2)
+						lowestfloor = topheight;
 				}
 
 			if (highestceiling < highceiling)
@@ -495,26 +529,40 @@ void P_LineOpening(line_t *linedef)
 	I_Assert(front != NULL);
 	I_Assert(back != NULL);
 
-	if (front->ceilingheight < back->ceilingheight)
-	{
-		opentop = front->ceilingheight;
-		highceiling = back->ceilingheight;
-	}
-	else
-	{
-		opentop = back->ceilingheight;
-		highceiling = front->ceilingheight;
-	}
+	{ // Set open and high/low values here
+		fixed_t frontheight, backheight;
 
-	if (front->floorheight > back->floorheight)
-	{
-		openbottom = front->floorheight;
-		lowfloor = back->floorheight;
-	}
-	else
-	{
-		openbottom = back->floorheight;
-		lowfloor = front->floorheight;
+		frontheight = P_GetCeilingZ(tmthing, front, tmx, tmy, linedef);
+		backheight = P_GetCeilingZ(tmthing, back, tmx, tmy, linedef);
+
+		if (frontheight < backheight)
+		{
+			opentop = frontheight;
+			highceiling = backheight;
+			opentopslope = front->c_slope;
+		}
+		else
+		{
+			opentop = backheight;
+			highceiling = frontheight;
+			opentopslope = back->c_slope;
+		}
+
+		frontheight = P_GetFloorZ(tmthing, front, tmx, tmy, linedef);
+		backheight = P_GetFloorZ(tmthing, back, tmx, tmy, linedef);
+
+		if (frontheight > backheight)
+		{
+			openbottom = frontheight;
+			lowfloor = backheight;
+			openbottomslope = front->f_slope;
+		}
+		else
+		{
+			openbottom = backheight;
+			lowfloor = frontheight;
+			openbottomslope = back->f_slope;
+		}
 	}
 
 	if (tmthing)
@@ -580,6 +628,10 @@ void P_LineOpening(line_t *linedef)
 			fixed_t highestfloor = openbottom;
 			fixed_t lowestfloor = lowfloor;
 			fixed_t delta1, delta2;
+#ifdef ESLOPE
+			pslope_t *ceilingslope = opentopslope;
+			pslope_t *floorslope = openbottomslope;
+#endif
 
 			// Check for frontsector's fake floors
 			for (rover = front->ffloors; rover; rover = rover->next)
@@ -593,23 +645,34 @@ void P_LineOpening(line_t *linedef)
 					|| (rover->flags & FF_BLOCKOTHERS && !tmthing->player)))
 					continue;
 
-				delta1 = abs(tmthing->z - (*rover->bottomheight + ((*rover->topheight - *rover->bottomheight)/2)));
-				delta2 = abs(thingtop - (*rover->bottomheight + ((*rover->topheight - *rover->bottomheight)/2)));
+				fixed_t topheight = P_GetFOFTopZ(tmthing, front, rover, tmx, tmy, linedef);
+				fixed_t bottomheight = P_GetFOFBottomZ(tmthing, front, rover, tmx, tmy, linedef);
+
+				delta1 = abs(tmthing->z - (bottomheight + ((topheight - bottomheight)/2)));
+				delta2 = abs(thingtop - (bottomheight + ((topheight - bottomheight)/2)));
 
 				if (delta1 >= delta2 && !(rover->flags & FF_PLATFORM)) // thing is below FOF
 				{
-					if (*rover->bottomheight < lowestceiling)
-						lowestceiling = *rover->bottomheight;
-					else if (*rover->bottomheight < highestceiling)
-						highestceiling = *rover->bottomheight;
+					if (bottomheight < lowestceiling) {
+						lowestceiling = bottomheight;
+#ifdef ESLOPE
+						ceilingslope = *rover->b_slope;
+#endif
+					}
+					else if (bottomheight < highestceiling)
+						highestceiling = bottomheight;
 				}
 
 				if (delta1 < delta2 && !(rover->flags & FF_REVERSEPLATFORM)) // thing is above FOF
 				{
-					if (*rover->topheight > highestfloor)
-						highestfloor = *rover->topheight;
-					else if (*rover->topheight > lowestfloor)
-						lowestfloor = *rover->topheight;
+					if (topheight > highestfloor) {
+						highestfloor = topheight;
+#ifdef ESLOPE
+						floorslope = *rover->t_slope;
+#endif
+					}
+					else if (topheight > lowestfloor)
+						lowestfloor = topheight;
 				}
 			}
 
@@ -625,23 +688,34 @@ void P_LineOpening(line_t *linedef)
 					|| (rover->flags & FF_BLOCKOTHERS && !tmthing->player)))
 					continue;
 
-				delta1 = abs(tmthing->z - (*rover->bottomheight + ((*rover->topheight - *rover->bottomheight)/2)));
-				delta2 = abs(thingtop - (*rover->bottomheight + ((*rover->topheight - *rover->bottomheight)/2)));
+				fixed_t topheight = P_GetFOFTopZ(tmthing, back, rover, tmx, tmy, linedef);
+				fixed_t bottomheight = P_GetFOFBottomZ(tmthing, back, rover, tmx, tmy, linedef);
+
+				delta1 = abs(tmthing->z - (bottomheight + ((topheight - bottomheight)/2)));
+				delta2 = abs(thingtop - (bottomheight + ((topheight - bottomheight)/2)));
 
 				if (delta1 >= delta2 && !(rover->flags & FF_PLATFORM)) // thing is below FOF
 				{
-					if (*rover->bottomheight < lowestceiling)
-						lowestceiling = *rover->bottomheight;
-					else if (*rover->bottomheight < highestceiling)
-						highestceiling = *rover->bottomheight;
+					if (bottomheight < lowestceiling) {
+						lowestceiling = bottomheight;
+#ifdef ESLOPE
+						ceilingslope = *rover->b_slope;
+#endif
+					}
+					else if (bottomheight < highestceiling)
+						highestceiling = bottomheight;
 				}
 
 				if (delta1 < delta2 && !(rover->flags & FF_REVERSEPLATFORM)) // thing is above FOF
 				{
-					if (*rover->topheight > highestfloor)
-						highestfloor = *rover->topheight;
-					else if (*rover->topheight > lowestfloor)
-						lowestfloor = *rover->topheight;
+					if (topheight > highestfloor) {
+						highestfloor = topheight;
+#ifdef ESLOPE
+						floorslope = *rover->t_slope;
+#endif
+					}
+					else if (topheight > lowestfloor)
+						lowestfloor = topheight;
 				}
 			}
 
@@ -653,13 +727,21 @@ void P_LineOpening(line_t *linedef)
 
 				delta1 = abs(tmthing->z - (polysec->floorheight + ((polysec->ceilingheight - polysec->floorheight)/2)));
 				delta2 = abs(thingtop - (polysec->floorheight + ((polysec->ceilingheight - polysec->floorheight)/2)));
-				if (polysec->floorheight < lowestceiling && delta1 >= delta2)
+				if (polysec->floorheight < lowestceiling && delta1 >= delta2) {
 					lowestceiling = polysec->floorheight;
+#ifdef ESLOPE
+					ceilingslope = NULL;
+#endif
+				}
 				else if (polysec->floorheight < highestceiling && delta1 >= delta2)
 					highestceiling = polysec->floorheight;
 
-				if (polysec->ceilingheight > highestfloor && delta1 < delta2)
+				if (polysec->ceilingheight > highestfloor && delta1 < delta2) {
 					highestfloor = polysec->ceilingheight;
+#ifdef ESLOPE
+					floorslope = NULL;
+#endif
+				}
 				else if (polysec->ceilingheight > lowestfloor && delta1 < delta2)
 					lowestfloor = polysec->ceilingheight;
 			}
@@ -667,11 +749,19 @@ void P_LineOpening(line_t *linedef)
 			if (highestceiling < highceiling)
 				highceiling = highestceiling;
 
-			if (highestfloor > openbottom)
+			if (highestfloor > openbottom) {
 				openbottom = highestfloor;
+#ifdef ESLOPE
+				openbottomslope = floorslope;
+#endif
+			}
 
-			if (lowestceiling < opentop)
+			if (lowestceiling < opentop) {
 				opentop = lowestceiling;
+#ifdef ESLOPE
+				opentopslope = ceilingslope;
+#endif
+			}
 
 			if (lowestfloor > lowfloor)
 				lowfloor = lowestfloor;
@@ -769,6 +859,7 @@ void P_SetThingPosition(mobj_t *thing)
 {                                                      // link into subsector
 	subsector_t *ss;
 	sector_t *oldsec = NULL;
+	fixed_t tfloorz, tceilz;
 
 	I_Assert(thing != NULL);
 	I_Assert(!P_MobjWasRemoved(thing));
@@ -838,12 +929,15 @@ void P_SetThingPosition(mobj_t *thing)
 	// sector's floor is the same height.
 	if (thing->player && oldsec != NULL && thing->subsector && oldsec != thing->subsector->sector)
 	{
+		tfloorz = P_GetFloorZ(thing, ss->sector, thing->x, thing->y, NULL);
+		tceilz = P_GetCeilingZ(thing, ss->sector, thing->x, thing->y, NULL);
+
 		if (thing->eflags & MFE_VERTICALFLIP)
 		{
-			if (thing->z + thing->height >= thing->subsector->sector->ceilingheight)
+			if (thing->z + thing->height >= tceilz)
 				thing->eflags |= MFE_JUSTSTEPPEDDOWN;
 		}
-		else if (thing->z <= thing->subsector->sector->floorheight)
+		else if (thing->z <= tfloorz)
 			thing->eflags |= MFE_JUSTSTEPPEDDOWN;
 	}
 }

src/p_maputl.h

@@ -55,6 +55,9 @@ void P_CreatePrecipSecNodeList(precipmobj_t *thing, fixed_t x,fixed_t y);
 boolean P_SceneryTryMove(mobj_t *thing, fixed_t x, fixed_t y);
 
 extern fixed_t opentop, openbottom, openrange, lowfloor, highceiling;
+#ifdef ESLOPE
+extern pslope_t *opentopslope, *openbottomslope;
+#endif
 
 void P_LineOpening(line_t *plinedef);
 

src/p_mobj.h

@@ -355,6 +355,10 @@ typedef struct mobj_s
 	INT32 cusval;
 	INT32 cvmem;
 
+#ifdef ESLOPE
+	struct pslope_s *standingslope; // The slope that the object is standing on (shouldn't need synced in savegames, right?)
+#endif
+
 	// WARNING: New fields must be added separately to savegame and Lua.
 } mobj_t;
 

src/p_saveg.c

@@ -30,6 +30,9 @@
 #include "r_sky.h"
 #include "p_polyobj.h"
 #include "lua_script.h"
+#ifdef ESLOPE
+#include "p_slopes.h"
+#endif
 
 savedata_t savedata;
 UINT8 *save_p;
@@ -921,7 +924,8 @@ typedef enum
 	MD2_EXTVAL1     = 1<<5,
 	MD2_EXTVAL2     = 1<<6,
 	MD2_HNEXT       = 1<<7,
-	MD2_HPREV       = 1<<8
+	MD2_HPREV       = 1<<8,
+	MD2_SLOPE       = 1<<9
 } mobj_diff2_t;
 
 typedef enum
@@ -1111,6 +1115,8 @@ static void SaveMobjThinker(const thinker_t *th, const UINT8 type)
 		diff2 |= MD2_HNEXT;
 	if (mobj->hprev)
 		diff2 |= MD2_HPREV;
+	if (mobj->standingslope)
+		diff2 |= MD2_SLOPE;
 	if (diff2 != 0)
 		diff |= MD_MORE;
 
@@ -1226,6 +1232,8 @@ static void SaveMobjThinker(const thinker_t *th, const UINT8 type)
 		WRITEUINT32(save_p, mobj->hnext->mobjnum);
 	if (diff2 & MD2_HPREV)
 		WRITEUINT32(save_p, mobj->hprev->mobjnum);
+	if (diff2 & MD2_SLOPE)
+		WRITEUINT16(save_p, mobj->standingslope->id);
 
 	WRITEUINT32(save_p, mobj->mobjnum);
 }
@@ -2079,6 +2087,9 @@ static void LoadMobjThinker(actionf_p1 thinker)
 		mobj->hnext = (mobj_t *)(size_t)READUINT32(save_p);
 	if (diff2 & MD2_HPREV)
 		mobj->hprev = (mobj_t *)(size_t)READUINT32(save_p);
+	if (diff2 & MD2_SLOPE)
+		mobj->standingslope = P_SlopeById(READUINT16(save_p));
+
 
 	if (diff & MD_REDFLAG)
 	{

src/p_setup.c

@@ -72,6 +72,10 @@
 #include "hardware/hw_light.h"
 #endif
 
+#ifdef ESLOPE
+#include "p_slopes.h"
+#endif
+
 //
 // Map MD5, calculated on level load.
 // Sent to clients in PT_SERVERINFO.
@@ -846,7 +850,7 @@ void P_ScanThings(INT16 mapnum, INT16 wadnum, INT16 lumpnum)
 //
 // P_LoadThings
 //
-static void P_LoadThings(lumpnum_t lumpnum)
+static void P_PrepareThings(lumpnum_t lumpnum)
 {
 	size_t i;
 	mapthing_t *mt;
@@ -884,13 +888,27 @@ static void P_LoadThings(lumpnum_t lumpnum)
 	}
 	Z_Free(datastart);
 
+}
+
+static void P_LoadThings(void)
+{
+	size_t i;
+	mapthing_t *mt;
+
+	// Loading the things lump itself into memory is now handled in P_PrepareThings, above
+
 	mt = mapthings;
 	numhuntemeralds = 0;
 	for (i = 0; i < nummapthings; i++, mt++)
 	{
+		sector_t *mtsector = R_PointInSubsector(mt->x << FRACBITS, mt->y << FRACBITS)->sector;
+
 		// Z for objects
-		mt->z = (INT16)(R_PointInSubsector(mt->x << FRACBITS, mt->y << FRACBITS)
-			->sector->floorheight>>FRACBITS);
+		mt->z = (INT16)(
+#ifdef ESLOPE
+				mtsector->f_slope ? P_GetZAt(mtsector->f_slope, mt->x << FRACBITS, mt->y << FRACBITS) :
+#endif
+				mtsector->floorheight)>>FRACBITS;
 
 		if (mt->type == 1700 // MT_AXIS
 			|| mt->type == 1701 // MT_AXISTRANSFER
@@ -2114,7 +2132,8 @@ void P_LoadThingsOnly(void)
 
 	P_LevelInitStuff();
 
-	P_LoadThings(lastloadedmaplumpnum + ML_THINGS);
+	P_PrepareThings(lastloadedmaplumpnum + ML_THINGS);
+	P_LoadThings();
 
 	P_SpawnSecretItems(true);
 }
@@ -2531,7 +2550,13 @@ boolean P_SetupLevel(boolean skipprecip)
 
 	P_MapStart();
 
-	P_LoadThings(lastloadedmaplumpnum + ML_THINGS);
+	P_PrepareThings(lastloadedmaplumpnum + ML_THINGS);
+
+#ifdef ESLOPE
+	P_ResetDynamicSlopes();
+#endif
+
+	P_LoadThings();
 
 	P_SpawnSecretItems(loademblems);
 

src/p_slopes.h

@@ -0,0 +1,80 @@
+// Emacs style mode select   -*- C++ -*-
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2004 Stephen McGranahan
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+//
+//--------------------------------------------------------------------------
+//
+// DESCRIPTION:
+//      Slopes
+//      SoM created 05/10/09
+//
+//-----------------------------------------------------------------------------
+
+#ifndef P_SLOPES_H__
+#define P_SLOPES_H__
+
+#ifdef ESLOPE
+void P_ResetDynamicSlopes(void);
+void P_RunDynamicSlopes(void);
+// P_SpawnSlope_Line
+// Creates one or more slopes based on the given line type and front/back
+// sectors.
+void P_SpawnSlope_Line(int linenum);
+
+#ifdef SPRINGCLEAN
+// Loads just map objects that make slopes,
+// terrain affecting objects have to be spawned first
+void P_SetSlopesFromVertexHeights(lumpnum_t lumpnum);
+
+typedef enum
+{
+	THING_SlopeFloorPointLine = 9500,
+	THING_SlopeCeilingPointLine = 9501,
+	THING_SetFloorSlope = 9502,
+	THING_SetCeilingSlope = 9503,
+	THING_CopyFloorPlane = 9510,
+	THING_CopyCeilingPlane = 9511,
+	THING_VavoomFloor=1500,
+	THING_VavoomCeiling=1501,
+	THING_VertexFloorZ=1504,
+	THING_VertexCeilingZ=1505,
+} slopething_e;
+#endif
+
+//
+// P_CopySectorSlope
+//
+// Searches through tagged sectors and copies
+//
+void P_CopySectorSlope(line_t *line);
+
+pslope_t *P_SlopeById(UINT16 id);
+
+// Returns the height of the sloped plane at (x, y) as a fixed_t
+fixed_t P_GetZAt(pslope_t *slope, fixed_t x, fixed_t y);
+
+// Lots of physics-based bullshit
+void P_QuantizeMomentumToSlope(vector3_t *momentum, pslope_t *slope);
+void P_SlopeLaunch(mobj_t *mo);
+void P_HandleSlopeLanding(mobj_t *thing, pslope_t *slope);
+void P_ButteredSlope(mobj_t *mo);
+
+#endif
+
+// EOF
+#endif // #ifdef ESLOPE

src/p_spec.c

@@ -3365,6 +3365,7 @@ sector_t *P_PlayerTouchingSectorSpecial(player_t *player, INT32 section, INT32 n
 static boolean P_ThingIsOnThe3DFloor(mobj_t *mo, sector_t *sector, sector_t *targetsec)
 {
 	ffloor_t *rover;
+	fixed_t top, bottom;
 
 	if (!mo->player) // should NEVER happen
 		return false;
@@ -3381,6 +3382,9 @@ static boolean P_ThingIsOnThe3DFloor(mobj_t *mo, sector_t *sector, sector_t *tar
 		//if (!(rover->flags & FF_EXISTS))
 		//	return false;
 
+		top = P_GetSpecialTopZ(mo, sector, targetsec);
+		bottom = P_GetSpecialBottomZ(mo, sector, targetsec);
+
 		// Check the 3D floor's type...
 		if (rover->flags & FF_BLOCKPLAYER)
 		{
@@ -3388,27 +3392,27 @@ static boolean P_ThingIsOnThe3DFloor(mobj_t *mo, sector_t *sector, sector_t *tar
 			if ((rover->master->frontsector->flags & SF_FLIPSPECIAL_FLOOR)
 				&& !(rover->master->frontsector->flags & SF_FLIPSPECIAL_CEILING))
 			{
-				if ((mo->eflags & MFE_VERTICALFLIP) || mo->z != *rover->topheight)
+				if ((mo->eflags & MFE_VERTICALFLIP) || mo->z != top)
 					return false;
 			}
 			else if ((rover->master->frontsector->flags & SF_FLIPSPECIAL_CEILING)
 				&& !(rover->master->frontsector->flags & SF_FLIPSPECIAL_FLOOR))
 			{
 				if (!(mo->eflags & MFE_VERTICALFLIP)
-					|| mo->z + mo->height != *rover->bottomheight)
+					|| mo->z + mo->height != bottom)
 					return false;
 			}
 			else if (rover->master->frontsector->flags & SF_FLIPSPECIAL_BOTH)
 			{
-				if (!((mo->eflags & MFE_VERTICALFLIP && mo->z + mo->height == *rover->bottomheight)
-					|| (!(mo->eflags & MFE_VERTICALFLIP) && mo->z == *rover->topheight)))
+				if (!((mo->eflags & MFE_VERTICALFLIP && mo->z + mo->height == bottom)
+					|| (!(mo->eflags & MFE_VERTICALFLIP) && mo->z == top)))
 					return false;
 			}
 		}
 		else
 		{
 			// Water and intangible FOFs
-			if (mo->z > *rover->topheight || (mo->z + mo->height) < *rover->bottomheight)
+			if (mo->z > top || (mo->z + mo->height) < bottom)
 				return false;
 		}
 
@@ -3426,9 +3430,9 @@ static boolean P_ThingIsOnThe3DFloor(mobj_t *mo, sector_t *sector, sector_t *tar
 static inline boolean P_MobjReadyToTrigger(mobj_t *mo, sector_t *sec)
 {
 	if (mo->eflags & MFE_VERTICALFLIP)
-		return (mo->z+mo->height == sec->ceilingheight && sec->flags & SF_FLIPSPECIAL_CEILING);
+		return (mo->z+mo->height == P_GetSpecialTopZ(mo, sec, sec) && sec->flags & SF_FLIPSPECIAL_CEILING);
 	else
-		return (mo->z == sec->floorheight && sec->flags & SF_FLIPSPECIAL_FLOOR);
+		return (mo->z == P_GetSpecialBottomZ(mo, sec, sec) && sec->flags & SF_FLIPSPECIAL_FLOOR);
 }
 
 /** Applies a sector special to a player.
@@ -4389,27 +4393,27 @@ static void P_PlayerOnSpecial3DFloor(player_t *player, sector_t *sector)
 			if ((rover->master->frontsector->flags & SF_FLIPSPECIAL_FLOOR)
 				&& !(rover->master->frontsector->flags & SF_FLIPSPECIAL_CEILING))
 			{
-				if ((player->mo->eflags & MFE_VERTICALFLIP) || player->mo->z != *rover->topheight)
+				if ((player->mo->eflags & MFE_VERTICALFLIP) || player->mo->z != P_GetSpecialTopZ(player->mo, sectors + rover->secnum, sector))
 					continue;
 			}
 			else if ((rover->master->frontsector->flags & SF_FLIPSPECIAL_CEILING)
 				&& !(rover->master->frontsector->flags & SF_FLIPSPECIAL_FLOOR))
 			{
 				if (!(player->mo->eflags & MFE_VERTICALFLIP)
-					|| player->mo->z + player->mo->height != *rover->bottomheight)
+					|| player->mo->z + player->mo->height != P_GetSpecialBottomZ(player->mo, sectors + rover->secnum, sector))
 					continue;
 			}
 			else if (rover->master->frontsector->flags & SF_FLIPSPECIAL_BOTH)
 			{
-				if (!((player->mo->eflags & MFE_VERTICALFLIP && player->mo->z + player->mo->height == *rover->bottomheight)
-					|| (!(player->mo->eflags & MFE_VERTICALFLIP) && player->mo->z == *rover->topheight)))
+				if (!((player->mo->eflags & MFE_VERTICALFLIP && player->mo->z + player->mo->height == P_GetSpecialBottomZ(player->mo, sectors + rover->secnum, sector))
+					|| (!(player->mo->eflags & MFE_VERTICALFLIP) && player->mo->z == P_GetSpecialTopZ(player->mo, sectors + rover->secnum, sector))))
 					continue;
 			}
 		}
 		else
 		{
 			// Water and DEATH FOG!!! heh
-			if (player->mo->z > *rover->topheight || (player->mo->z + player->mo->height) < *rover->bottomheight)
+			if (player->mo->z > P_GetSpecialTopZ(player->mo, sectors + rover->secnum, sector) || (player->mo->z + player->mo->height) < P_GetSpecialBottomZ(player->mo, sectors + rover->secnum, sector))
 				continue;
 		}
 
@@ -4519,6 +4523,7 @@ static void P_PlayerOnSpecial3DFloor(player_t *player, sector_t *sector)
 static void P_RunSpecialSectorCheck(player_t *player, sector_t *sector)
 {
 	boolean nofloorneeded = false;
+	fixed_t f_affectpoint, c_affectpoint;
 
 	if (!sector->special) // nothing special, exit
 		return;
@@ -4581,16 +4586,19 @@ static void P_RunSpecialSectorCheck(player_t *player, sector_t *sector)
 		return;
 	}
 
+	f_affectpoint = P_GetSpecialBottomZ(player->mo, sector, sector);
+	c_affectpoint = P_GetSpecialTopZ(player->mo, sector, sector);
+
 	// Only go further if on the ground
-	if ((sector->flags & SF_FLIPSPECIAL_FLOOR) && !(sector->flags & SF_FLIPSPECIAL_CEILING) && player->mo->z != sector->floorheight)
+	if ((sector->flags & SF_FLIPSPECIAL_FLOOR) && !(sector->flags & SF_FLIPSPECIAL_CEILING) && player->mo->z != f_affectpoint)
 		return;
 
-	if ((sector->flags & SF_FLIPSPECIAL_CEILING) && !(sector->flags & SF_FLIPSPECIAL_FLOOR) && player->mo->z + player->mo->height != sector->ceilingheight)
+	if ((sector->flags & SF_FLIPSPECIAL_CEILING) && !(sector->flags & SF_FLIPSPECIAL_FLOOR) && player->mo->z + player->mo->height != c_affectpoint)
 		return;
 
 	if ((sector->flags & SF_FLIPSPECIAL_BOTH)
-		&& player->mo->z != sector->floorheight
-		&& player->mo->z + player->mo->height != sector->ceilingheight)
+		&& player->mo->z != f_affectpoint
+		&& player->mo->z + player->mo->height != c_affectpoint)
 		return;
 
 	P_ProcessSpecialSector(player, sector, NULL);
@@ -4751,6 +4759,9 @@ void P_UpdateSpecials(void)
 	// POINT LIMIT
 	P_CheckPointLimit();
 
+	// Dynamic slopeness
+	P_RunDynamicSlopes();
+
 	// ANIMATE TEXTURES
 	for (anim = anims; anim < lastanim; anim++)
 	{
@@ -4894,6 +4905,12 @@ static ffloor_t *P_AddFakeFloor(sector_t *sec, sector_t *sec2, line_t *master, f
 	ffloor->topyoffs = &sec2->ceiling_yoffs;
 	ffloor->topangle = &sec2->ceilingpic_angle;
 
+#ifdef ESLOPE
+	// Add slopes
+	ffloor->t_slope = &sec2->c_slope;
+	ffloor->b_slope = &sec2->f_slope;
+#endif
+
 	if ((flags & FF_SOLID) && (master->flags & ML_EFFECT1)) // Block player only
 		flags &= ~FF_BLOCKOTHERS;
 
@@ -5327,6 +5344,7 @@ void T_LaserFlash(laserthink_t *flash)
 	sector_t *sourcesec;
 	ffloor_t *ffloor = flash->ffloor;
 	sector_t *sector = flash->sector;
+	fixed_t top, bottom;
 
 	if (!ffloor || !(ffloor->flags & FF_EXISTS))
 		return;
@@ -5350,8 +5368,11 @@ void T_LaserFlash(laserthink_t *flash)
 			&& thing->flags & MF_BOSS)
 			continue; // Don't hurt bosses
 
-		if (thing->z >= sourcesec->ceilingheight
-		|| thing->z + thing->height <= sourcesec->floorheight)
+		top = P_GetSpecialTopZ(thing, sourcesec, sector);
+		bottom = P_GetSpecialBottomZ(thing, sourcesec, sector);
+
+		if (thing->z >= top
+		|| thing->z + thing->height <= bottom)
 			continue;
 
 		if (thing->flags & MF_SHOOTABLE)
@@ -6430,6 +6451,14 @@ void P_SpawnSpecials(INT32 fromnetsave)
 					sectors[s].midmap = lines[i].frontsector->midmap;
 				break;
 
+#ifdef ESLOPE // Slope copy specials. Handled here for sanity.
+			case 720:
+			case 721:
+			case 722:
+				P_CopySectorSlope(&lines[i]);
+				break;
+#endif
+
 			default:
 				break;
 		}
@@ -6634,6 +6663,8 @@ void T_Scroll(scroll_t *s)
 						if (thing->eflags & MFE_PUSHED) // Already pushed this tic by an exclusive pusher.
 							continue;
 
+						height = P_GetSpecialBottomZ(thing, sec, psec);
+
 						if (!(thing->flags & MF_NOCLIP)) // Thing must be clipped
 						if (!(thing->flags & MF_NOGRAVITY || thing->z+thing->height != height)) // Thing must a) be non-floating and have z+height == height
 						{
@@ -6654,6 +6685,8 @@ void T_Scroll(scroll_t *s)
 					if (thing->eflags & MFE_PUSHED)
 						continue;
 
+					height = P_GetSpecialBottomZ(thing, sec, sec);
+
 					if (!(thing->flags & MF_NOCLIP) &&
 						(!(thing->flags & MF_NOGRAVITY || thing->z > height)))
 					{
@@ -6693,6 +6726,8 @@ void T_Scroll(scroll_t *s)
 						if (thing->eflags & MFE_PUSHED)
 							continue;
 
+						height = P_GetSpecialTopZ(thing, sec, psec);
+
 						if (!(thing->flags & MF_NOCLIP)) // Thing must be clipped
 						if (!(thing->flags & MF_NOGRAVITY || thing->z != height))// Thing must a) be non-floating and have z == height
 						{
@@ -6713,6 +6748,8 @@ void T_Scroll(scroll_t *s)
 					if (thing->eflags & MFE_PUSHED)
 						continue;
 
+					height = P_GetSpecialTopZ(thing, sec, sec);
+
 					if (!(thing->flags & MF_NOCLIP) &&
 						(!(thing->flags & MF_NOGRAVITY || thing->z+thing->height < height)))
 					{
@@ -7006,7 +7043,7 @@ static void Add_Friction(INT32 friction, INT32 movefactor, INT32 affectee, INT32
   */
 void T_Friction(friction_t *f)
 {
-	sector_t *sec;
+	sector_t *sec, *referrer;
 	mobj_t *thing;
 	msecnode_t *node;
 
@@ -7015,7 +7052,7 @@ void T_Friction(friction_t *f)
 	// Make sure the sector type hasn't changed
 	if (f->roverfriction)
 	{
-		sector_t *referrer = sectors + f->referrer;
+		referrer = sectors + f->referrer;
 
 		if (!(GETSECSPECIAL(referrer->special, 3) == 1
 			|| GETSECSPECIAL(referrer->special, 3) == 3))
@@ -7047,9 +7084,7 @@ void T_Friction(friction_t *f)
 		{
 			if (f->roverfriction)
 			{
-				sector_t *referrer = &sectors[f->referrer];
-
-				if (thing->floorz != referrer->ceilingheight)
+				if (thing->floorz != P_GetSpecialTopZ(thing, referrer, sec))
 				{
 					node = node->m_snext;
 					continue;
@@ -7062,7 +7097,7 @@ void T_Friction(friction_t *f)
 					thing->movefactor = f->movefactor;
 				}
 			}
-			else if (sec->floorheight == thing->floorz && (thing->friction == ORIG_FRICTION // normal friction?
+			else if (P_GetSpecialBottomZ(thing, sec, sec) == thing->floorz && (thing->friction == ORIG_FRICTION // normal friction?
 				|| f->friction < thing->friction))
 			{
 				thing->friction = f->friction;
@@ -7336,7 +7371,7 @@ static inline boolean PIT_PushThing(mobj_t *thing)
   */
 void T_Pusher(pusher_t *p)
 {
-	sector_t *sec;
+	sector_t *sec, *referrer;
 	mobj_t *thing;
 	msecnode_t *node;
 	INT32 xspeed = 0,yspeed = 0;
@@ -7345,7 +7380,6 @@ void T_Pusher(pusher_t *p)
 	//INT32 ht = 0;
 	boolean inFOF;
 	boolean touching;
-	boolean foundfloor = false;
 	boolean moved;
 
 	xspeed = yspeed = 0;
@@ -7357,19 +7391,16 @@ void T_Pusher(pusher_t *p)
 
 	if (p->roverpusher)
 	{
-		sector_t *referrer = &sectors[p->referrer];
+		referrer = &sectors[p->referrer];
 
-		if (GETSECSPECIAL(referrer->special, 3) == 2
-			|| GETSECSPECIAL(referrer->special, 3) == 3)
-			foundfloor = true;
+		if (!(GETSECSPECIAL(referrer->special, 3) == 2
+			|| GETSECSPECIAL(referrer->special, 3) == 3))
+			return;
 	}
 	else if (!(GETSECSPECIAL(sec->special, 3) == 2
 			|| GETSECSPECIAL(sec->special, 3) == 3))
 		return;
 
-	if (p->roverpusher && foundfloor == false) // Not even a 3d floor has the PUSH_MASK.
-		return;
-
 	// For constant pushers (wind/current) there are 3 situations:
 	//
 	// 1) Affected Thing is above the floor.
@@ -7444,41 +7475,38 @@ void T_Pusher(pusher_t *p)
 		// Find the area that the 'thing' is in
 		if (p->roverpusher)
 		{
-			sector_t *referrer = &sectors[p->referrer];
-			INT32 special;
+			fixed_t top, bottom;
 
-			special = GETSECSPECIAL(referrer->special, 3);
-
-			if (!(special == 2 || special == 3))
-				return;
+			top = P_GetSpecialTopZ(thing, referrer, sec);
+			bottom = P_GetSpecialBottomZ(thing, referrer, sec);
 
 			if (thing->eflags & MFE_VERTICALFLIP)
 			{
-				if (referrer->floorheight > thing->z + thing->height
-					|| referrer->ceilingheight < (thing->z + (thing->height >> 1)))
+				if (bottom > thing->z + thing->height
+					|| top < (thing->z + (thing->height >> 1)))
 					continue;
 
-				if (thing->z < referrer->floorheight)
+				if (thing->z < bottom)
 					touching = true;
 
-				if (thing->z + (thing->height >> 1) > referrer->floorheight)
+				if (thing->z + (thing->height >> 1) > bottom)
 					inFOF = true;
 
 			}
 			else
 			{
-				if (referrer->ceilingheight < thing->z || referrer->floorheight > (thing->z + (thing->height >> 1)))
+				if (top < thing->z || referrer->floorheight > (thing->z + (thing->height >> 1)))
 					continue;
-				if (thing->z + thing->height > referrer->ceilingheight)
+				if (thing->z + thing->height > top)
 					touching = true;
 
-				if (thing->z + (thing->height >> 1) < referrer->ceilingheight)
+				if (thing->z + (thing->height >> 1) < top)
 					inFOF = true;
 			}
 		}
 		else // Treat the entire sector as one big FOF
 		{
-			if (thing->z == thing->subsector->sector->floorheight)
+			if (thing->z == P_GetSpecialBottomZ(thing, sec, sec))
 				touching = true;
 			else if (p->type != p_current)
 				inFOF = true;

src/p_user.c

@@ -1212,7 +1212,7 @@ boolean P_IsObjectOnGroundIn(mobj_t *mo, sector_t *sec)
 	if (mo->eflags & MFE_VERTICALFLIP)
 	{
 		// Detect if the player is on the ceiling.
-		if (mo->z+mo->height >= sec->ceilingheight)
+		if (mo->z+mo->height >= P_GetSpecialTopZ(mo, sec, sec))
 			return true;
 		// Otherwise, detect if the player is on the bottom of a FOF.
 		else
@@ -1236,7 +1236,7 @@ boolean P_IsObjectOnGroundIn(mobj_t *mo, sector_t *sec)
 					continue;
 
 				// Actually check if the player is on the suitable FOF.
-				if (mo->z+mo->height == *rover->bottomheight)
+				if (mo->z+mo->height == P_GetSpecialBottomZ(mo, sectors + rover->secnum, sec))
 					return true;
 			}
 		}
@@ -1245,7 +1245,7 @@ boolean P_IsObjectOnGroundIn(mobj_t *mo, sector_t *sec)
 	else
 	{
 		// Detect if the player is on the floor.
-		if (mo->z <= sec->floorheight)
+		if (mo->z <= P_GetSpecialBottomZ(mo, sec, sec))
 			return true;
 		// Otherwise, detect if the player is on the top of a FOF.
 		else
@@ -1269,7 +1269,7 @@ boolean P_IsObjectOnGroundIn(mobj_t *mo, sector_t *sec)
 					continue;
 
 				// Actually check if the player is on the suitable FOF.
-				if (mo->z == *rover->topheight)
+				if (mo->z == P_GetSpecialTopZ(mo, sectors + rover->secnum, sec))
 					return true;
 			}
 		}
@@ -1790,6 +1790,9 @@ static void P_CheckBouncySectors(player_t *player)
 	fixed_t oldx;
 	fixed_t oldy;
 	fixed_t oldz;
+#ifdef ESLOPE
+	vector3_t momentum;
+#endif
 
 	oldx = player->mo->x;
 	oldy = player->mo->y;
@@ -1810,16 +1813,21 @@ static void P_CheckBouncySectors(player_t *player)
 		{
 			ffloor_t *rover;
 			boolean top = true;
+			fixed_t topheight, bottomheight;
 
 			for (rover = node->m_sector->ffloors; rover; rover = rover->next)
 			{
-				if (player->mo->z > *rover->topheight)
+				topheight = P_GetFOFTopZ(player->mo, node->m_sector, rover, player->mo->x, player->mo->y, NULL);
+				bottomheight = P_GetFOFBottomZ(player->mo, node->m_sector, rover, player->mo->x, player->mo->y, NULL);
+
+				if (player->mo->z > topheight)
 					continue;
 
-				if (player->mo->z + player->mo->height < *rover->bottomheight)
+				if (player->mo->z + player->mo->height < bottomheight)
 					continue;
 
-				if (oldz < *rover->topheight && oldz > *rover->bottomheight)
+				if (oldz < P_GetFOFTopZ(player->mo, node->m_sector, rover, oldx, oldy, NULL)
+						&& oldz + player->mo->height > P_GetFOFBottomZ(player->mo, node->m_sector, rover, oldx, oldy, NULL))
 					top = false;
 
 				if (GETSECSPECIAL(rover->master->frontsector->special, 1) == 15)
@@ -1834,7 +1842,29 @@ static void P_CheckBouncySectors(player_t *player)
 					{
 						fixed_t newmom;
 
+#ifdef ESLOPE
+						pslope_t *slope;
+						if (abs(oldz - topheight) < abs(oldz + player->mo->height - bottomheight)) { // Hit top
+							slope = *rover->t_slope;
+						} else { // Hit bottom
+							slope = *rover->b_slope;
+						}
+
+						momentum.x = player->mo->momx;
+						momentum.y = player->mo->momy;
+						momentum.z = player->mo->momz*2;
+
+						if (slope) {
+							// Reverse quantizing might could use its own function later
+							slope->zangle = ANGLE_MAX-slope->zangle;
+							P_QuantizeMomentumToSlope(&momentum, slope);
+							slope->zangle = ANGLE_MAX-slope->zangle;
+						}
+
+						newmom = momentum.z = -FixedMul(momentum.z,linedist)/2;
+#else
 						newmom = -FixedMul(player->mo->momz,linedist);
+#endif
 
 						if (abs(newmom) < (linedist*2))
 						{
@@ -1857,7 +1887,18 @@ static void P_CheckBouncySectors(player_t *player)
 						else if (newmom < -P_GetPlayerHeight(player)/2)
 							newmom = -P_GetPlayerHeight(player)/2;
 
+#ifdef ESLOPE
+						momentum.z = newmom*2;
+
+						if (slope)
+							P_QuantizeMomentumToSlope(&momentum, slope);
+
+						player->mo->momx = momentum.x;
+						player->mo->momy = momentum.y;
+						player->mo->momz = momentum.z/2;
+#else
 						player->mo->momz = newmom;
+#endif
 
 						if (player->pflags & PF_SPINNING)
 						{
@@ -2275,10 +2316,23 @@ static void P_DoClimbing(player_t *player)
 		floorclimb = false;
 		boostup = false;
 		skyclimber = false;
+		fixed_t floorheight, ceilingheight; // ESLOPE
+
+#ifdef ESLOPE
+		floorheight = glidesector->sector->f_slope ? P_GetZAt(glidesector->sector->f_slope, player->mo->x, player->mo->y)
+		                                           : glidesector->sector->floorheight;
+		ceilingheight = glidesector->sector->c_slope ? P_GetZAt(glidesector->sector->c_slope, player->mo->x, player->mo->y)
+		                                             : glidesector->sector->ceilingheight;
+#else
+		floorheight = glidesector->sector->floorheight;
+		ceilingheight = glidesector->sector->ceilingheight;
+#endif
 
 		if (glidesector->sector->ffloors)
 		{
 			ffloor_t *rover;
+			fixed_t topheight, bottomheight; // ESLOPE
+
 			for (rover = glidesector->sector->ffloors; rover; rover = rover->next)
 			{
 				if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER) || (rover->flags & FF_BUSTUP))
@@ -2286,13 +2340,21 @@ static void P_DoClimbing(player_t *player)
 
 				floorclimb = true;
 
+#ifdef ESLOPE
+				bottomheight = *rover->b_slope ? P_GetZAt(*rover->b_slope, player->mo->x, player->mo->y) : *rover->bottomheight;
+				topheight = *rover->t_slope ? P_GetZAt(*rover->t_slope, player->mo->x, player->mo->y) : *rover->topheight;
+#else
+				bottomheight = *rover->bottomheight;
+				topheight = *rover->topheight;
+#endif
+
 				// Only supports rovers that are moving like an 'elevator', not just the top or bottom.
 				if (rover->master->frontsector->floorspeed && rover->master->frontsector->ceilspeed == 42)
 				{
-					if ((!(player->mo->eflags & MFE_VERTICALFLIP) && (*rover->bottomheight < player->mo->z+player->mo->height)
-						&& (*rover->topheight >= player->mo->z + FixedMul(16*FRACUNIT, player->mo->scale)))
-					|| ((player->mo->eflags & MFE_VERTICALFLIP) && (*rover->topheight > player->mo->z)
-						&& (*rover->bottomheight <= player->mo->z + player->mo->height - FixedMul(16*FRACUNIT, player->mo->scale))))
+					if ((!(player->mo->eflags & MFE_VERTICALFLIP) && (bottomheight < player->mo->z+player->mo->height)
+						&& (topheight >= player->mo->z + FixedMul(16*FRACUNIT, player->mo->scale)))
+					|| ((player->mo->eflags & MFE_VERTICALFLIP) && (topheight > player->mo->z)
+						&& (bottomheight <= player->mo->z + player->mo->height - FixedMul(16*FRACUNIT, player->mo->scale))))
 					{
 						if (cmd->forwardmove != 0)
 							player->mo->momz += rover->master->frontsector->floorspeed;
@@ -2308,8 +2370,9 @@ static void P_DoClimbing(player_t *player)
 				if (player->mo->eflags & MFE_VERTICALFLIP)
 				{
 					// Trying to climb down past the bottom of the FOF
-					if ((*rover->topheight >= player->mo->z + player->mo->height) && ((player->mo->z + player->mo->height + player->mo->momz) >= *rover->topheight))
+					if ((topheight >= player->mo->z + player->mo->height) && ((player->mo->z + player->mo->height + player->mo->momz) >= topheight))
 					{
+						fixed_t bottomheight2;
 						ffloor_t *roverbelow;
 						boolean foundfof = false;
 						floorclimb = true;
@@ -2324,7 +2387,13 @@ static void P_DoClimbing(player_t *player)
 							if (roverbelow == rover)
 								continue;
 
-							if (*roverbelow->bottomheight < *rover->topheight + FixedMul(16*FRACUNIT, player->mo->scale))
+#ifdef ESLOPE
+							bottomheight2 = *roverbelow->b_slope ? P_GetZAt(*roverbelow->b_slope, player->mo->x, player->mo->y) : *roverbelow->bottomheight;
+#else
+							bottomheight2 = *roverbelow->bottomheight;
+#endif
+
+							if (bottomheight2 < topheight + FixedMul(16*FRACUNIT, player->mo->scale))
 								foundfof = true;
 						}
 
@@ -2333,7 +2402,7 @@ static void P_DoClimbing(player_t *player)
 					}
 
 					// Below the FOF
-					if (*rover->topheight <= player->mo->z)
+					if (topheight <= player->mo->z)
 					{
 						floorclimb = false;
 						boostup = false;
@@ -2341,7 +2410,7 @@ static void P_DoClimbing(player_t *player)
 					}
 
 					// Above the FOF
-					if (*rover->bottomheight > player->mo->z + player->mo->height - FixedMul(16*FRACUNIT, player->mo->scale))
+					if (bottomheight > player->mo->z + player->mo->height - FixedMul(16*FRACUNIT, player->mo->scale))
 					{
 						floorclimb = false;
 						thrust = true;
@@ -2351,8 +2420,9 @@ static void P_DoClimbing(player_t *player)
 				else
 				{
 					// Trying to climb down past the bottom of a FOF
-					if ((*rover->bottomheight <= player->mo->z) && ((player->mo->z + player->mo->momz) <= *rover->bottomheight))
+					if ((bottomheight <= player->mo->z) && ((player->mo->z + player->mo->momz) <= bottomheight))
 					{
+						fixed_t topheight2;
 						ffloor_t *roverbelow;
 						boolean foundfof = false;
 						floorclimb = true;
@@ -2367,7 +2437,13 @@ static void P_DoClimbing(player_t *player)
 							if (roverbelow == rover)
 								continue;
 
-							if (*roverbelow->topheight > *rover->bottomheight - FixedMul(16*FRACUNIT, player->mo->scale))
+#ifdef ESLOPE
+							topheight2 = *roverbelow->t_slope ? P_GetZAt(*roverbelow->t_slope, player->mo->x, player->mo->y) : *roverbelow->topheight;
+#else
+							topheight2 = *roverbelow->topheight;
+#endif
+
+							if (topheight2 > bottomheight - FixedMul(16*FRACUNIT, player->mo->scale))
 								foundfof = true;
 						}
 
@@ -2376,7 +2452,7 @@ static void P_DoClimbing(player_t *player)
 					}
 
 					// Below the FOF
-					if (*rover->bottomheight >= player->mo->z + player->mo->height)
+					if (bottomheight >= player->mo->z + player->mo->height)
 					{
 						floorclimb = false;
 						boostup = false;
@@ -2384,7 +2460,7 @@ static void P_DoClimbing(player_t *player)
 					}
 
 					// Above the FOF
-					if (*rover->topheight < player->mo->z + FixedMul(16*FRACUNIT, player->mo->scale))
+					if (topheight < player->mo->z + FixedMul(16*FRACUNIT, player->mo->scale))
 					{
 						floorclimb = false;
 						thrust = true;
@@ -2405,7 +2481,7 @@ static void P_DoClimbing(player_t *player)
 		if (player->mo->eflags & MFE_VERTICALFLIP)
 		{
 			// Trying to climb down past the upper texture area
-			if ((glidesector->sector->floorheight >= player->mo->z + player->mo->height) && ((player->mo->z + player->mo->height + player->mo->momz) >= glidesector->sector->floorheight))
+			if ((floorheight >= player->mo->z + player->mo->height) && ((player->mo->z + player->mo->height + player->mo->momz) >= floorheight))
 			{
 				boolean foundfof = false;
 				floorclimb = true;
@@ -2413,13 +2489,20 @@ static void P_DoClimbing(player_t *player)
 				// Is there a FOF directly below that we can move onto?
 				if (glidesector->sector->ffloors)
 				{
+					fixed_t bottomheight;
 					ffloor_t *rover;
 					for (rover = glidesector->sector->ffloors; rover; rover = rover->next)
 					{
 						if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER) || (rover->flags & FF_BUSTUP))
 							continue;
 
-						if (*rover->bottomheight < glidesector->sector->floorheight + FixedMul(16*FRACUNIT, player->mo->scale))
+#ifdef ESLOPE
+						bottomheight = *rover->b_slope ? P_GetZAt(*rover->b_slope, player->mo->x, player->mo->y) : *rover->bottomheight;
+#else
+						bottomheight = *rover->bottomheight;
+#endif
+
+						if (bottomheight < floorheight + FixedMul(16*FRACUNIT, player->mo->scale))
 						{
 							foundfof = true;
 							break;
@@ -2432,8 +2515,8 @@ static void P_DoClimbing(player_t *player)
 			}
 
 			// Reached the top of the lower texture area
-			if (!floorclimb && glidesector->sector->ceilingheight > player->mo->z + player->mo->height - FixedMul(16*FRACUNIT, player->mo->scale)
-				&& (glidesector->sector->ceilingpic == skyflatnum || glidesector->sector->floorheight < (player->mo->z - FixedMul(8*FRACUNIT, player->mo->scale))))
+			if (!floorclimb && ceilingheight > player->mo->z + player->mo->height - FixedMul(16*FRACUNIT, player->mo->scale)
+				&& (glidesector->sector->ceilingpic == skyflatnum || floorheight < (player->mo->z - FixedMul(8*FRACUNIT, player->mo->scale))))
 			{
 				thrust = true;
 				boostup = true;
@@ -2443,7 +2526,7 @@ static void P_DoClimbing(player_t *player)
 		else
 		{
 			// Trying to climb down past the upper texture area
-			if ((glidesector->sector->ceilingheight <= player->mo->z) && ((player->mo->z + player->mo->momz) <= glidesector->sector->ceilingheight))
+			if ((ceilingheight <= player->mo->z) && ((player->mo->z + player->mo->momz) <= ceilingheight))
 			{
 				boolean foundfof = false;
 				floorclimb = true;
@@ -2457,7 +2540,7 @@ static void P_DoClimbing(player_t *player)
 						if (!(rover->flags & FF_EXISTS) || !(rover->flags & FF_BLOCKPLAYER) || (rover->flags & FF_BUSTUP))
 							continue;
 
-						if (*rover->topheight > glidesector->sector->ceilingheight - FixedMul(16*FRACUNIT, player->mo->scale))
+						if (*rover->topheight > ceilingheight - FixedMul(16*FRACUNIT, player->mo->scale))
 						{
 							foundfof = true;
 							break;
@@ -2470,7 +2553,7 @@ static void P_DoClimbing(player_t *player)
 			}
 
 			// Allow climbing from a FOF or lower texture onto the upper texture and vice versa.
-			if (player->mo->z > glidesector->sector->ceilingheight - FixedMul(16*FRACUNIT, player->mo->scale))
+			if (player->mo->z > ceilingheight - FixedMul(16*FRACUNIT, player->mo->scale))
 			{
 				floorclimb = true;
 				thrust = false;
@@ -2478,8 +2561,8 @@ static void P_DoClimbing(player_t *player)
 			}
 
 			// Reached the top of the lower texture area
-			if (!floorclimb && glidesector->sector->floorheight < player->mo->z + FixedMul(16*FRACUNIT, player->mo->scale)
-				&& (glidesector->sector->ceilingpic == skyflatnum || glidesector->sector->ceilingheight > (player->mo->z + player->mo->height + FixedMul(8*FRACUNIT, player->mo->scale))))
+			if (!floorclimb && floorheight < player->mo->z + FixedMul(16*FRACUNIT, player->mo->scale)
+				&& (glidesector->sector->ceilingpic == skyflatnum || ceilingheight > (player->mo->z + player->mo->height + FixedMul(8*FRACUNIT, player->mo->scale))))
 			{
 				thrust = true;
 				boostup = true;
@@ -2488,14 +2571,14 @@ static void P_DoClimbing(player_t *player)
 		}
 
 		// Trying to climb on the sky
-		if ((glidesector->sector->ceilingheight < player->mo->z) && glidesector->sector->ceilingpic == skyflatnum)
+		if ((ceilingheight < player->mo->z) && glidesector->sector->ceilingpic == skyflatnum)
 		{
 			skyclimber = true;
 		}
 
 		// Climbing on the lower texture area?
-		if ((!(player->mo->eflags & MFE_VERTICALFLIP) && player->mo->z + FixedMul(16*FRACUNIT, player->mo->scale) < glidesector->sector->floorheight)
-			|| ((player->mo->eflags & MFE_VERTICALFLIP) && player->mo->z + player->mo->height <= glidesector->sector->floorheight))
+		if ((!(player->mo->eflags & MFE_VERTICALFLIP) && player->mo->z + FixedMul(16*FRACUNIT, player->mo->scale) < floorheight)
+			|| ((player->mo->eflags & MFE_VERTICALFLIP) && player->mo->z + player->mo->height <= floorheight))
 		{
 			floorclimb = true;
 
@@ -2511,8 +2594,8 @@ static void P_DoClimbing(player_t *player)
 			}
 		}
 		// Climbing on the upper texture area?
-		else if ((!(player->mo->eflags & MFE_VERTICALFLIP) && player->mo->z >= glidesector->sector->ceilingheight)
-			|| ((player->mo->eflags & MFE_VERTICALFLIP) && player->mo->z + player->mo->height - FixedMul(16*FRACUNIT, player->mo->scale) > glidesector->sector->ceilingheight))
+		else if ((!(player->mo->eflags & MFE_VERTICALFLIP) && player->mo->z >= ceilingheight)
+			|| ((player->mo->eflags & MFE_VERTICALFLIP) && player->mo->z + player->mo->height - FixedMul(16*FRACUNIT, player->mo->scale) > ceilingheight))
 		{
 			floorclimb = true;
 
@@ -3704,7 +3787,11 @@ static void P_DoSpinDash(player_t *player, ticcmd_t *cmd)
 	if ((player->charability2 == CA2_SPINDASH) && !(player->pflags & PF_SLIDING) && !player->exiting
 		&& !P_PlayerInPain(player)) // subsequent revs
 	{
-		if ((cmd->buttons & BT_USE) && player->speed < FixedMul(5<<FRACBITS, player->mo->scale) && !player->mo->momz && onground && !(player->pflags & PF_USEDOWN) && !(player->pflags & PF_SPINNING))
+		if ((cmd->buttons & BT_USE) && player->speed < FixedMul(5<<FRACBITS, player->mo->scale) && !player->mo->momz && onground && !(player->pflags & PF_USEDOWN) && !(player->pflags & PF_SPINNING)
+#ifdef ESLOPE
+			&& (!player->mo->standingslope || abs(player->mo->standingslope->zdelta) < FRACUNIT/2)
+#endif
+			)
 		{
 			player->mo->momx = player->cmomx;
 			player->mo->momy = player->cmomy;
@@ -3736,7 +3823,11 @@ static void P_DoSpinDash(player_t *player, ticcmd_t *cmd)
 		// down the spin button and not spinning.
 		// AKA Just go into a spin on the ground, you idiot. ;)
 		else if ((cmd->buttons & BT_USE || ((twodlevel || (player->mo->flags2 & MF2_TWOD)) && cmd->forwardmove < -20))
-			&& !player->climbing && !player->mo->momz && onground && player->speed > FixedMul(5<<FRACBITS, player->mo->scale) && !(player->pflags & PF_USEDOWN) && !(player->pflags & PF_SPINNING))
+			&& !player->climbing && !player->mo->momz && onground && (player->speed > FixedMul(5<<FRACBITS, player->mo->scale)
+#ifdef ESLOPE
+			|| (player->mo->standingslope && abs(player->mo->standingslope->zdelta) >= FRACUNIT/2)
+#endif
+			) && !(player->pflags & PF_USEDOWN) && !(player->pflags & PF_SPINNING))
 		{
 			player->pflags |= PF_SPINNING;
 			P_SetPlayerMobjState(player->mo, S_PLAY_SPIN);
@@ -3748,7 +3839,11 @@ static void P_DoSpinDash(player_t *player, ticcmd_t *cmd)
 
 	// Rolling normally
 	if (onground && player->pflags & PF_SPINNING && !(player->pflags & PF_STARTDASH)
-		&& player->speed < FixedMul(5*FRACUNIT,player->mo->scale))
+		&& player->speed < FixedMul(5*FRACUNIT,player->mo->scale)
+#ifdef ESLOPE
+			&& (!player->mo->standingslope || abs(player->mo->standingslope->zdelta) < FRACUNIT/2)
+#endif
+			)
 	{
 		if (GETSECSPECIAL(player->mo->subsector->sector->special, 4) == 7 || (player->mo->ceilingz - player->mo->floorz < P_GetPlayerHeight(player)))
 			P_InstaThrust(player->mo, player->mo->angle, FixedMul(10*FRACUNIT, player->mo->scale));
@@ -4455,12 +4550,16 @@ static void P_3dMovement(player_t *player)
 	angle_t dangle; // replaces old quadrants bits
 	fixed_t normalspd = FixedMul(player->normalspeed, player->mo->scale);
 	boolean analogmove = false;
-#ifndef OLD_MOVEMENT_CODE
 	fixed_t oldMagnitude, newMagnitude;
+#ifdef ESLOPE
+	vector3_t totalthrust;
+
+	totalthrust.x = totalthrust.y = 0; // I forget if this is needed
+	totalthrust.z = FRACUNIT*P_MobjFlip(player->mo)/3; // A bit of extra push-back on slopes
+#endif // ESLOPE
 
 	// Get the old momentum; this will be needed at the end of the function! -SH
 	oldMagnitude = R_PointToDist2(player->mo->momx - player->cmomx, player->mo->momy - player->cmomy, 0, 0);
-#endif
 
 	analogmove = P_AnalogMove(player);
 
@@ -4637,17 +4736,10 @@ static void P_3dMovement(player_t *player)
 		}
 
 		movepushforward = FixedMul(movepushforward, player->mo->scale);
-#ifdef OLD_MOVEMENT_CODE
-		if (player->speed < topspeed && mforward && cmd->forwardmove > 0) // Sonic's Speed
-			P_Thrust(player->mo, movepushangle, movepushforward);
-		else if (mforward && cmd->forwardmove < 0)
-			P_Thrust(player->mo, movepushangle, movepushforward);
-		else if (player->speed < topspeed && mbackward && cmd->forwardmove < 0)
-			P_Thrust(player->mo, movepushangle, movepushforward);
-		else if (mbackward && cmd->forwardmove > 0)
-			P_Thrust(player->mo, movepushangle, movepushforward);
-		else if (!mforward && !mbackward)
-			P_Thrust(player->mo, movepushangle, movepushforward);
+
+#ifdef ESLOPE
+		totalthrust.x += P_ReturnThrustX(player->mo, movepushangle, movepushforward);
+		totalthrust.y += P_ReturnThrustY(player->mo, movepushangle, movepushforward);
 #else
 		P_Thrust(player->mo, movepushangle, movepushforward);
 #endif
@@ -4666,33 +4758,12 @@ static void P_3dMovement(player_t *player)
 		if (!(player->pflags & PF_GLIDING || player->exiting || P_PlayerInPain(player)))
 		{
 			angle_t controldirection;
-#ifdef OLD_MOVEMENT_CODE
-			angle_t controlplayerdirection;
-			boolean cforward; // controls pointing forward from the player
-			boolean cbackward; // controls pointing backward from the player
-			angle_t dangle;
 
-			cforward = cbackward = false;
-#endif
 			// Calculate the angle at which the controls are pointing
 			// to figure out the proper mforward and mbackward.
 			// (Why was it so complicated before? ~Red)
 			controldirection = R_PointToAngle2(0, 0, cmd->forwardmove*FRACUNIT, -cmd->sidemove*FRACUNIT)+movepushangle;
 
-#ifdef OLD_MOVEMENT_CODE
-			controlplayerdirection = player->mo->angle;
-
-			dangle = controldirection - controlplayerdirection;
-
-			if (dangle > ANGLE_180) //flip to keep to one side
-				dangle = InvAngle(dangle);
-
-			if (dangle > ANGLE_90)
-				cbackward = true; // Controls pointing backwards from player
-			else
-				cforward = true; // Controls pointing in player's general direction
-#endif
-
 			movepushforward = max(abs(cmd->sidemove), abs(cmd->forwardmove)) * (thrustfactor * acceleration);
 
 			// allow very small movement while in air for gameplay
@@ -4715,13 +4786,10 @@ static void P_3dMovement(player_t *player)
 			movepushsideangle = controldirection;
 
 			movepushforward = FixedMul(movepushforward, player->mo->scale);
-#ifdef OLD_MOVEMENT_CODE
-			if (player->speed < topspeed)
-				P_Thrust(player->mo, controldirection, movepushforward);
-			else if ((mforward) && (cbackward))
-				P_Thrust(player->mo, controldirection, movepushforward);
-			else if ((mbackward) && (cforward))
-				P_Thrust(player->mo, controldirection, movepushforward);
+
+#ifdef ESLOPE
+			totalthrust.x += P_ReturnThrustX(player->mo, controldirection, movepushforward);
+			totalthrust.y += P_ReturnThrustY(player->mo, controldirection, movepushforward);
 #else
 			P_Thrust(player->mo, controldirection, movepushforward);
 #endif
@@ -4729,29 +4797,6 @@ static void P_3dMovement(player_t *player)
 	}
 	else if (cmd->sidemove && !(player->pflags & PF_GLIDING) && !player->exiting && !P_PlayerInPain(player))
 	{
-#ifdef OLD_MOVEMENT_CODE
-		boolean mright = 0;
-		boolean mleft = 0;
-		angle_t sideangle;
-
-		sideangle = player->mo->angle - ANGLE_90;
-
-		// Monster Iestyn - 04-11-13
-		// Quadrants are stupid, excessive and broken, let's do this a much simpler way!
-		// Get delta angle from rmom angle and player angle first
-		dangle = R_PointToAngle2(0,0, player->rmomx, player->rmomy) - sideangle;
-		if (dangle > ANGLE_180)
-			dangle = InvAngle(dangle);
-
-		// now use it to determine direction!
-		if (dangle <= ANGLE_45) // angles 0-45 or 315-360
-			mright = 1; // going right
-		else if (dangle >= ANGLE_135) // angles 135-225
-			mleft = 1; // going left
-
-		// anything else will leave both at 0, so no need to do anything else
-#endif
-
 		movepushside = cmd->sidemove * (thrustfactor * acceleration);
 
 		if (!onground)
@@ -4774,19 +4819,37 @@ static void P_3dMovement(player_t *player)
 
 		// Finally move the player now that his speed/direction has been decided.
 		movepushside = FixedMul(movepushside, player->mo->scale);
-#ifdef OLD_MOVEMENT_CODE
-		if (player->speed < topspeed)
-			P_Thrust(player->mo, movepushsideangle, movepushside);
-		else if (mright && cmd->sidemove < 0)
-			P_Thrust(player->mo, movepushsideangle, movepushside);
-		else if (mleft && cmd->sidemove > 0)
-			P_Thrust(player->mo, movepushsideangle, movepushside);
+
+#ifdef ESLOPE
+		totalthrust.x += P_ReturnThrustX(player->mo, movepushsideangle, movepushside);
+		totalthrust.y += P_ReturnThrustY(player->mo, movepushsideangle, movepushside);
 #else
 		P_Thrust(player->mo, movepushsideangle, movepushside);
 #endif
 	}
 
-#ifndef OLD_MOVEMENT_CODE
+#ifdef ESLOPE
+	if ((totalthrust.x || totalthrust.y)
+		&& player->mo->standingslope && abs(player->mo->standingslope->zdelta) > FRACUNIT/2) {
+		// Factor thrust to slope, but only for the part pushing up it!
+		// The rest is unaffected.
+		angle_t thrustangle = R_PointToAngle2(0, 0, totalthrust.x, totalthrust.y)-player->mo->standingslope->xydirection;
+
+		if (player->mo->standingslope->zdelta < 0) { // Direction goes down, so thrustangle needs to face toward
+			if (thrustangle < ANGLE_90 || thrustangle > ANGLE_270) {
+				P_QuantizeMomentumToSlope(&totalthrust, player->mo->standingslope);
+			}
+		} else { // Direction goes up, so thrustangle needs to face away
+			if (thrustangle > ANGLE_90 && thrustangle < ANGLE_270) {
+				P_QuantizeMomentumToSlope(&totalthrust, player->mo->standingslope);
+			}
+		}
+	}
+
+	player->mo->momx += totalthrust.x;
+	player->mo->momy += totalthrust.y;
+#endif
+
 	// Time to ask three questions:
 	// 1) Are we over topspeed?
 	// 2) If "yes" to 1, were we moving over topspeed to begin with?
@@ -4820,7 +4883,6 @@ static void P_3dMovement(player_t *player)
 			player->mo->momy = tempmomy + player->cmomy;
 		}
 	}
-#endif
 }
 
 //

src/r_bsp.c

@@ -459,6 +459,11 @@ static void R_AddLine(seg_t *line)
 	doorclosed = 0;
 
 	// Closed door.
+#ifdef ESLOPE
+	// Just don't bother checking this if one side is sloped. This is probably inefficient, but it's better than
+	// random renderer stopping around slopes...
+	if (!(frontsector->f_slope || frontsector->c_slope || backsector->f_slope || backsector->c_slope))
+#endif
 	if (backsector->ceilingheight <= frontsector->floorheight
 		|| backsector->floorheight >= frontsector->ceilingheight)
 	{
@@ -487,6 +492,10 @@ static void R_AddLine(seg_t *line)
 #endif
 		backsector->ceilingpic == frontsector->ceilingpic
 		&& backsector->floorpic == frontsector->floorpic
+#ifdef ESLOPE
+		&& backsector->f_slope == frontsector->f_slope
+		&& backsector->c_slope == frontsector->c_slope
+#endif
 		&& backsector->lightlevel == frontsector->lightlevel
 		&& !curline->sidedef->midtexture
 		// Check offsets too!
@@ -842,11 +851,19 @@ static void R_Subsector(size_t num)
 			sub->sector->moved = frontsector->moved = false;
 		}
 
-		light = R_GetPlaneLight(frontsector, frontsector->floorheight, false);
+		light = R_GetPlaneLight(frontsector,
+#ifdef ESLOPE
+								frontsector->f_slope ? P_GetZAt(frontsector->f_slope, frontsector->soundorg.x, frontsector->soundorg.y) :
+#endif
+								frontsector->floorheight, false);
 		if (frontsector->floorlightsec == -1)
 			floorlightlevel = *frontsector->lightlist[light].lightlevel;
 		floorcolormap = frontsector->lightlist[light].extra_colormap;
-		light = R_GetPlaneLight(frontsector, frontsector->ceilingheight, false);
+		light = R_GetPlaneLight(frontsector,
+#ifdef ESLOPE
+								frontsector->c_slope ? P_GetZAt(frontsector->c_slope, frontsector->soundorg.x, frontsector->soundorg.y) :
+#endif
+								frontsector->ceilingheight, false);
 		if (frontsector->ceilinglightsec == -1)
 			ceilinglightlevel = *frontsector->lightlist[light].lightlevel;
 		ceilingcolormap = frontsector->lightlist[light].extra_colormap;
@@ -854,32 +871,52 @@ static void R_Subsector(size_t num)
 
 	sub->sector->extra_colormap = frontsector->extra_colormap;
 
-	if ((frontsector->floorheight < viewz || (frontsector->heightsec != -1
+	if (((
+#ifdef ESLOPE
+			frontsector->f_slope ? P_GetZAt(frontsector->f_slope, viewx, viewy) :
+#endif
+		frontsector->floorheight) < viewz || (frontsector->heightsec != -1
 		&& sectors[frontsector->heightsec].ceilingpic == skyflatnum)))
 	{
 		floorplane = R_FindPlane(frontsector->floorheight, frontsector->floorpic, floorlightlevel,
-			frontsector->floor_xoffs, frontsector->floor_yoffs, frontsector->floorpic_angle, floorcolormap, NULL);
+			frontsector->floor_xoffs, frontsector->floor_yoffs, frontsector->floorpic_angle, floorcolormap, NULL
+#ifdef ESLOPE
+			, frontsector->f_slope
+#endif
+			);
 	}
 	else
 		floorplane = NULL;
 
-	if ((frontsector->ceilingheight > viewz || frontsector->ceilingpic == skyflatnum
+	if (((
+#ifdef ESLOPE
+			frontsector->c_slope ? P_GetZAt(frontsector->c_slope, viewx, viewy) :
+#endif
+		frontsector->ceilingheight) > viewz || frontsector->ceilingpic == skyflatnum
 		|| (frontsector->heightsec != -1
 		&& sectors[frontsector->heightsec].floorpic == skyflatnum)))
 	{
 		ceilingplane = R_FindPlane(frontsector->ceilingheight, frontsector->ceilingpic,
 			ceilinglightlevel, frontsector->ceiling_xoffs, frontsector->ceiling_yoffs, frontsector->ceilingpic_angle,
-			ceilingcolormap, NULL);
+			ceilingcolormap, NULL
+#ifdef ESLOPE
+			, frontsector->c_slope
+#endif
+			);
 	}
 	else
 		ceilingplane = NULL;
 
 	numffloors = 0;
+#ifdef ESLOPE
+	ffloor[numffloors].slope = NULL;
+#endif
 	ffloor[numffloors].plane = NULL;
 	ffloor[numffloors].polyobj = NULL;
 	if (frontsector->ffloors)
 	{
 		ffloor_t *rover;
+		fixed_t heightcheck;
 
 		for (rover = frontsector->ffloors; rover && numffloors < MAXFFLOORS; rover = rover->next)
 		{
@@ -897,18 +934,47 @@ static void R_Subsector(size_t num)
 
 			ffloor[numffloors].plane = NULL;
 			ffloor[numffloors].polyobj = NULL;
+
+			heightcheck =
+#ifdef ESLOPE
+				*rover->b_slope ? P_GetZAt(*rover->b_slope, viewx, viewy) :
+#endif
+				*rover->bottomheight;
 			if (*rover->bottomheight <= frontsector->ceilingheight
 				&& *rover->bottomheight >= frontsector->floorheight
-				&& ((viewz < *rover->bottomheight && !(rover->flags & FF_INVERTPLANES))
-				|| (viewz > *rover->bottomheight && (rover->flags & FF_BOTHPLANES))))
+				&& ((viewz < heightcheck && !(rover->flags & FF_INVERTPLANES))
+				|| (viewz > heightcheck && (rover->flags & FF_BOTHPLANES))))
 			{
+#ifdef ESLOPE
+				light = R_GetPlaneLight(frontsector,
+					*rover->b_slope ? P_GetZAt(*rover->b_slope, frontsector->soundorg.x, frontsector->soundorg.y) : *rover->bottomheight,
+					viewz < heightcheck);
+#else
 				light = R_GetPlaneLight(frontsector, *rover->bottomheight,
 					viewz < *rover->bottomheight);
+#endif
 				ffloor[numffloors].plane = R_FindPlane(*rover->bottomheight, *rover->bottompic,
 					*frontsector->lightlist[light].lightlevel, *rover->bottomxoffs,
-					*rover->bottomyoffs, *rover->bottomangle, frontsector->lightlist[light].extra_colormap, rover);
+					*rover->bottomyoffs, *rover->bottomangle, frontsector->lightlist[light].extra_colormap, rover
+#ifdef ESLOPE
+					, *rover->b_slope
+#endif
+					);
+
+#ifdef ESLOPE
+				ffloor[numffloors].slope = *rover->b_slope;
+
+				// Tell the renderer this sector has slopes in it.
+				if (ffloor[numffloors].slope)
+					frontsector->hasslope = true;
+#endif
+
+				ffloor[numffloors].height =
+#ifdef ESLOPE
+				*rover->b_slope ? P_GetZAt(*rover->b_slope, viewx, viewy) :
+#endif
+				*rover->bottomheight;
 
-				ffloor[numffloors].height = *rover->bottomheight;
 				ffloor[numffloors].ffloor = rover;
 				numffloors++;
 			}
@@ -916,16 +982,46 @@ static void R_Subsector(size_t num)
 				break;
 			ffloor[numffloors].plane = NULL;
 			ffloor[numffloors].polyobj = NULL;
+
+			heightcheck =
+#ifdef ESLOPE
+				*rover->t_slope ? P_GetZAt(*rover->t_slope, viewx, viewy) :
+#endif
+				*rover->topheight;
 			if (*rover->topheight >= frontsector->floorheight
 				&& *rover->topheight <= frontsector->ceilingheight
-				&& ((viewz > *rover->topheight && !(rover->flags & FF_INVERTPLANES))
-				|| (viewz < *rover->topheight && (rover->flags & FF_BOTHPLANES))))
+				&& ((viewz > heightcheck && !(rover->flags & FF_INVERTPLANES))
+				|| (viewz < heightcheck && (rover->flags & FF_BOTHPLANES))))
 			{
+#ifdef ESLOPE
+				light = R_GetPlaneLight(frontsector,
+					*rover->t_slope ? P_GetZAt(*rover->t_slope, frontsector->soundorg.x, frontsector->soundorg.y) : *rover->topheight,
+					viewz < heightcheck);
+#else
 				light = R_GetPlaneLight(frontsector, *rover->topheight, viewz < *rover->topheight);
+#endif
 				ffloor[numffloors].plane = R_FindPlane(*rover->topheight, *rover->toppic,
 					*frontsector->lightlist[light].lightlevel, *rover->topxoffs, *rover->topyoffs, *rover->topangle,
-					frontsector->lightlist[light].extra_colormap, rover);
-				ffloor[numffloors].height = *rover->topheight;
+					frontsector->lightlist[light].extra_colormap, rover
+#ifdef ESLOPE
+					, *rover->t_slope
+#endif
+					);
+
+#ifdef ESLOPE
+				ffloor[numffloors].slope = *rover->t_slope;
+
+				// Tell the renderer this sector has slopes in it.
+				if (ffloor[numffloors].slope)
+					frontsector->hasslope = true;
+#endif
+
+				ffloor[numffloors].height =
+#ifdef ESLOPE
+				*rover->t_slope ? P_GetZAt(*rover->t_slope, viewx, viewy) :
+#endif
+				*rover->topheight;
+
 				ffloor[numffloors].ffloor = rover;
 				numffloors++;
 			}
@@ -977,11 +1073,18 @@ static void R_Subsector(size_t num)
 						polysec->lightlevel, xoff, yoff,
 						polysec->floorpic_angle-po->angle,
 						NULL,
-						NULL);
+						NULL
+#ifdef ESLOPE
+					, NULL // will ffloors be slopable eventually?
+#endif
+					);
 				//ffloor[numffloors].plane->polyobj = po;
 
 				ffloor[numffloors].height = polysec->floorheight;
 				ffloor[numffloors].polyobj = po;
+#ifdef ESLOPE
+				ffloor[numffloors].slope = NULL;
+#endif
 //				ffloor[numffloors].ffloor = rover;
 				po->visplane = ffloor[numffloors].plane;
 				numffloors++;
@@ -1014,11 +1117,18 @@ static void R_Subsector(size_t num)
 				light = 0;
 				ffloor[numffloors].plane = R_FindPlane(polysec->ceilingheight, polysec->ceilingpic,
 					polysec->lightlevel, xoff, yoff, polysec->ceilingpic_angle-po->angle,
-					NULL, NULL);
+					NULL, NULL
+#ifdef ESLOPE
+					, NULL // will ffloors be slopable eventually?
+#endif
+					);
 				//ffloor[numffloors].plane->polyobj = po;
 
 				ffloor[numffloors].polyobj = po;
 				ffloor[numffloors].height = polysec->ceilingheight;
+#ifdef ESLOPE
+				ffloor[numffloors].slope = NULL;
+#endif
 //				ffloor[numffloors].ffloor = rover;
 				po->visplane = ffloor[numffloors].plane;
 				numffloors++;
@@ -1077,6 +1187,11 @@ void R_Prep3DFloors(sector_t *sector)
 	fixed_t bestheight, maxheight;
 	INT32 count, i, mapnum;
 	sector_t *sec;
+#ifdef ESLOPE
+	pslope_t *bestslope;
+	fixed_t heighttest; // I think it's better to check the Z height at the sector's center
+	                    // than assume unsloped heights are accurate indicators of order in sloped sectors. -Red
+#endif
 
 	count = 1;
 	for (rover = sector->ffloors; rover; rover = rover->next)
@@ -1099,7 +1214,14 @@ void R_Prep3DFloors(sector_t *sector)
 	else
 		memset(sector->lightlist, 0, sizeof (lightlist_t) * count);
 
+#ifdef ESLOPE
+	heighttest = sector->c_slope ? P_GetZAt(sector->c_slope, sector->soundorg.x, sector->soundorg.y) : sector->ceilingheight;
+
+	sector->lightlist[0].height = heighttest + 1;
+	sector->lightlist[0].slope = sector->c_slope;
+#else
 	sector->lightlist[0].height = sector->ceilingheight + 1;
+#endif
 	sector->lightlist[0].lightlevel = &sector->lightlevel;
 	sector->lightlist[0].caster = NULL;
 	sector->lightlist[0].extra_colormap = sector->extra_colormap;
@@ -1117,6 +1239,29 @@ void R_Prep3DFloors(sector_t *sector)
 				&& !(rover->flags & FF_CUTLEVEL) && !(rover->flags & FF_CUTSPRITES)))
 			continue;
 
+#ifdef ESLOPE
+			heighttest = *rover->t_slope ? P_GetZAt(*rover->t_slope, sector->soundorg.x, sector->soundorg.y) : *rover->topheight;
+
+			if (heighttest > bestheight && heighttest < maxheight)
+			{
+				best = rover;
+				bestheight = heighttest;
+				bestslope = *rover->t_slope;
+				continue;
+			}
+			if (rover->flags & FF_DOUBLESHADOW) {
+				heighttest = *rover->b_slope ? P_GetZAt(*rover->b_slope, sector->soundorg.x, sector->soundorg.y) : *rover->bottomheight;
+
+				if (heighttest > bestheight
+					&& heighttest < maxheight)
+				{
+					best = rover;
+					bestheight = heighttest;
+					bestslope = *rover->b_slope;
+					continue;
+				}
+			}
+#else
 			if (*rover->topheight > bestheight && *rover->topheight < maxheight)
 			{
 				best = rover;
@@ -1130,6 +1275,7 @@ void R_Prep3DFloors(sector_t *sector)
 				bestheight = *rover->bottomheight;
 				continue;
 			}
+#endif
 		}
 		if (!best)
 		{
@@ -1140,6 +1286,9 @@ void R_Prep3DFloors(sector_t *sector)
 		sector->lightlist[i].height = maxheight = bestheight;
 		sector->lightlist[i].caster = best;
 		sector->lightlist[i].flags = best->flags;
+#ifdef ESLOPE
+		sector->lightlist[i].slope = bestslope;
+#endif
 		sec = &sectors[best->secnum];
 		mapnum = sec->midmap;
 		if (mapnum >= 0 && (size_t)mapnum < num_extra_colormaps)
@@ -1165,7 +1314,12 @@ void R_Prep3DFloors(sector_t *sector)
 
 		if (best->flags & FF_DOUBLESHADOW)
 		{
+#ifdef ESLOPE
+			heighttest = *best->b_slope ? P_GetZAt(*best->b_slope, sector->soundorg.x, sector->soundorg.y) : *best->bottomheight;
+			if (bestheight == heighttest) ///TODO: do this in a more efficient way -Red
+#else
 			if (bestheight == *best->bottomheight)
+#endif
 			{
 				sector->lightlist[i].lightlevel = sector->lightlist[best->lastlight].lightlevel;
 				sector->lightlist[i].extra_colormap =

src/r_defs.h

@@ -155,6 +155,12 @@ typedef struct ffloor_s
 	fixed_t *bottomyoffs;
 	angle_t *bottomangle;
 
+#ifdef ESLOPE
+	// Pointers to pointers. Yup.
+	struct pslope_s **t_slope;
+	struct pslope_s **b_slope;
+#endif
+
 	size_t secnum;
 	ffloortype_e flags;
 	struct line_s *master;
@@ -184,6 +190,9 @@ typedef struct lightlist_s
 	extracolormap_t *extra_colormap;
 	INT32 flags;
 	ffloor_t *caster;
+#ifdef ESLOPE
+	struct pslope_s *slope; // FF_DOUBLESHADOW makes me have to store this pointer here. Bluh bluh.
+#endif
 } lightlist_t;
 
 
@@ -224,6 +233,52 @@ typedef struct secplane_t
 	fixed_t a, b, c, d, ic;
 } secplane_t;
 
+// Slopes
+#ifdef ESLOPE
+typedef enum {
+	SL_NOPHYSICS = 1, // Don't do momentum adjustment with this slope
+	SL_NODYNAMIC = 1<<1, // Slope will never need to move during the level, so don't fuss with recalculating it
+	SL_ANCHORVERTEX = 1<<2, // Slope is using a Slope Vertex Thing to anchor its position
+	SL_VERTEXSLOPE = 1<<3, // Slope is built from three Slope Vertex Things
+} slopeflags_t;
+
+typedef struct pslope_s
+{
+	UINT16 id; // The number of the slope, mostly used for netgame syncing purposes
+
+	// --- Information used in clipping/projection ---
+	// Origin vector for the plane
+	vector3_t o;
+
+	// 2-Dimentional vector (x, y) normalized. Used to determine distance from
+	// the origin in 2d mapspace. (Basically a thrust of FRACUNIT in xydirection angle)
+	vector2_t d;
+
+	// The rate at which z changes based on distance from the origin plane.
+	fixed_t zdelta;
+
+	// The normal of the slope; will always point upward, and thus be inverted on ceilings. I think it's only needed for physics? -Red
+	vector3_t normal;
+
+	// For comparing when a slope should be rendered
+	fixed_t lowz;
+	fixed_t highz;
+
+	// This values only check and must be updated if the slope itself is modified
+	angle_t zangle; // Angle of the plane going up from the ground (not mesured in degrees)
+	angle_t xydirection; // The direction the slope is facing (north, west, south, etc.)
+
+	struct line_s *sourceline; // The line that generated the slope
+	fixed_t extent; // Distance value used for recalculating zdelta
+	UINT8 refpos; // 1=front floor 2=front ceiling 3=back floor 4=back ceiling (used for dynamic sloping)
+
+	UINT8 flags; // Slope options
+	mapthing_t **vertices; // List should be three long for slopes made by vertex things, or one long for slopes using one vertex thing to anchor
+
+	struct pslope_s *next; // Make a linked list of dynamic slopes, for easy reference later
+} pslope_t;
+#endif
+
 typedef enum
 {
 	SF_FLIPSPECIAL_FLOOR    =  1,
@@ -337,6 +392,13 @@ typedef struct sector_s
 	precipmobj_t *preciplist;
 	struct mprecipsecnode_s *touching_preciplist;
 
+#ifdef ESLOPE
+	// Eternity engine slope
+	pslope_t *f_slope; // floor slope
+	pslope_t *c_slope; // ceiling slope
+	boolean hasslope; // The sector, or one of its visible FOFs, contains a slope
+#endif
+
 	// these are saved for netgames, so do not let Lua touch these!
 
 	// offsets sector spawned with (via linedef type 7)
@@ -612,6 +674,12 @@ typedef struct drawseg_s
 	INT16 *thicksidecol;
 	INT32 numthicksides;
 	fixed_t frontscale[MAXVIDWIDTH];
+
+#ifdef ESLOPE
+	fixed_t maskedtextureheight[MAXVIDWIDTH]; // For handling sloped midtextures
+
+	vertex_t leftpos, rightpos; // Used for rendering FOF walls with slopes
+#endif
 } drawseg_t;
 
 typedef enum

src/r_draw.c

@@ -103,6 +103,12 @@ fixed_t ds_xfrac, ds_yfrac, ds_xstep, ds_ystep;
 UINT8 *ds_source; // start of a 64*64 tile image
 UINT8 *ds_transmap; // one of the translucency tables
 
+#ifdef ESLOPE
+pslope_t *ds_slope; // Current slope being used
+floatv3_t ds_su, ds_sv, ds_sz; // Vectors for... stuff?
+float focallengthf, zeroheight;
+#endif
+
 /**	\brief Variable flat sizes
 */
 

src/r_draw.h

@@ -60,6 +60,16 @@ extern fixed_t ds_xfrac, ds_yfrac, ds_xstep, ds_ystep;
 extern UINT8 *ds_source; // start of a 64*64 tile image
 extern UINT8 *ds_transmap;
 
+#ifdef ESLOPE
+typedef struct {
+	float x, y, z;
+} floatv3_t;
+
+pslope_t *ds_slope; // Current slope being used
+floatv3_t ds_su, ds_sv, ds_sz; // Vectors for... stuff?
+float focallengthf, zeroheight;
+#endif
+
 // Variable flat sizes
 extern UINT32 nflatxshift;
 extern UINT32 nflatyshift;
@@ -141,6 +151,11 @@ void ASMCALL R_DrawSpan_8_MMX(void);
 void R_DrawTranslatedColumn_8(void);
 void R_DrawTranslatedTranslucentColumn_8(void);
 void R_DrawSpan_8(void);
+#ifdef ESLOPE
+void R_DrawTiltedSpan_8(void);
+void R_DrawTiltedTranslucentSpan_8(void);
+void R_DrawTiltedSplat_8(void);
+#endif
 void R_DrawSplat_8(void);
 void R_DrawTranslucentSplat_8(void);
 void R_DrawTranslucentSpan_8(void);

src/r_draw8.c

@@ -526,6 +526,436 @@ void R_DrawSpan_8 (void)
 	}
 }
 
+#ifdef ESLOPE
+// R_CalcTiltedLighting
+// Exactly what it says on the tin. I wish I wasn't too lazy to explain things properly.
+static size_t tiltlighting[MAXVIDWIDTH];
+void R_CalcTiltedLighting(fixed_t start, fixed_t end)
+{
+	// ZDoom uses a different lighting setup to us, and I couldn't figure out how to adapt their version
+	// of this function. Here's my own.
+	INT32 left = ds_x1, right = ds_x2;
+	fixed_t step = (end-start)/(ds_x2-ds_x1+1);
+	size_t i;
+
+	// I wanna do some optimizing by checking for out-of-range segments on either side to fill in all at once,
+	// but I'm too bad at coding to not crash the game trying to do that. I guess this is fast enough for now...
+
+	for (i = left; i <= right; i++) {
+		tiltlighting[i] = (start += step) >> FRACBITS;
+		if (tiltlighting[i] < 0)
+			tiltlighting[i] = 0;
+		else if (tiltlighting[i] >= MAXLIGHTSCALE)
+			tiltlighting[i] = MAXLIGHTSCALE-1;
+	}
+}
+
+
+/**	\brief The R_DrawTiltedSpan_8 function
+	Draw slopes! Holy sheit!
+*/
+void R_DrawTiltedSpan_8(void)
+{
+	// x1, x2 = ds_x1, ds_x2
+	int width = ds_x2 - ds_x1;
+	double iz, uz, vz;
+	UINT32 u, v;
+	int i;
+
+	UINT8 *source;
+	UINT8 *colormap;
+	UINT8 *dest;
+
+	iz = ds_sz.z + ds_sz.y*(centery-ds_y) + ds_sz.x*(ds_x1-centerx);
+
+	// Lighting is simple. It's just linear interpolation from start to end
+	{
+		float planelightfloat = BASEVIDWIDTH*BASEVIDWIDTH/vid.width / (zeroheight - FIXED_TO_FLOAT(viewz)) / 21.0f;
+		float lightstart, lightend;
+
+		lightend = (iz + ds_sz.x*width) * planelightfloat;
+		lightstart = iz * planelightfloat;
+
+		R_CalcTiltedLighting(FLOAT_TO_FIXED(lightstart), FLOAT_TO_FIXED(lightend));
+		//CONS_Printf("tilted lighting %f to %f (foc %f)\n", lightstart, lightend, focallengthf);
+	}
+
+	uz = ds_su.z + ds_su.y*(centery-ds_y) + ds_su.x*(ds_x1-centerx);
+	vz = ds_sv.z + ds_sv.y*(centery-ds_y) + ds_sv.x*(ds_x1-centerx);
+
+	dest = ylookup[ds_y] + columnofs[ds_x1];
+	source = ds_source;
+	//colormap = ds_colormap;
+
+#if 0	// The "perfect" reference version of this routine. Pretty slow.
+		// Use it only to see how things are supposed to look.
+	i = 0;
+	do
+	{
+		double z = 1.f/iz;
+		u = (INT64)(uz*z) + viewx;
+		v = (INT64)(vz*z) + viewy;
+
+		colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+
+		*dest = colormap[source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)]];
+		dest++;
+		iz += ds_sz.x;
+		uz += ds_su.x;
+		vz += ds_sv.x;
+	} while (--width >= 0);
+#else
+#define SPANSIZE 16
+#define INVSPAN	0.0625f
+
+	double startz = 1.f/iz;
+	double startu = uz*startz;
+	double startv = vz*startz;
+	double izstep, uzstep, vzstep;
+
+	izstep = ds_sz.x * SPANSIZE;
+	uzstep = ds_su.x * SPANSIZE;
+	vzstep = ds_sv.x * SPANSIZE;
+	//x1 = 0;
+	width++;
+
+	while (width >= SPANSIZE)
+	{
+		iz += izstep;
+		uz += uzstep;
+		vz += vzstep;
+
+		double endz = 1.f/iz;
+		double endu = uz*endz;
+		double endv = vz*endz;
+		UINT32 stepu = (INT64)((endu - startu) * INVSPAN);
+		UINT32 stepv = (INT64)((endv - startv) * INVSPAN);
+		u = (INT64)(startu) + viewx;
+		v = (INT64)(startv) + viewy;
+
+		for (i = SPANSIZE-1; i >= 0; i--)
+		{
+			colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+			*dest = colormap[source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)]];
+			dest++;
+			u += stepu;
+			v += stepv;
+		}
+		startu = endu;
+		startv = endv;
+		width -= SPANSIZE;
+	}
+	if (width > 0)
+	{
+		if (width == 1)
+		{
+			u = (INT64)(startu);
+			v = (INT64)(startv);
+			colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+			*dest = colormap[source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)]];
+		}
+		else
+		{
+			double left = width;
+			iz += ds_sz.x * left;
+			uz += ds_su.x * left;
+			vz += ds_sv.x * left;
+
+			double endz = 1.f/iz;
+			double endu = uz*endz;
+			double endv = vz*endz;
+			left = 1.f/left;
+			UINT32 stepu = (INT64)((endu - startu) * left);
+			UINT32 stepv = (INT64)((endv - startv) * left);
+			u = (INT64)(startu) + viewx;
+			v = (INT64)(startv) + viewy;
+
+			for (; width != 0; width--)
+			{
+				colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+				*dest = colormap[source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)]];
+				dest++;
+				u += stepu;
+				v += stepv;
+			}
+		}
+	}
+#endif
+}
+
+
+/**	\brief The R_DrawTiltedTranslucentSpan_8 function
+	Like DrawTiltedSpan, but translucent
+*/
+void R_DrawTiltedTranslucentSpan_8(void)
+{
+	// x1, x2 = ds_x1, ds_x2
+	int width = ds_x2 - ds_x1;
+	double iz, uz, vz;
+	UINT32 u, v;
+	int i;
+
+	UINT8 *source;
+	UINT8 *colormap;
+	UINT8 *dest;
+
+	iz = ds_sz.z + ds_sz.y*(centery-ds_y) + ds_sz.x*(ds_x1-centerx);
+
+	// Lighting is simple. It's just linear interpolation from start to end
+	{
+		float planelightfloat = BASEVIDWIDTH*BASEVIDWIDTH/vid.width / (zeroheight - FIXED_TO_FLOAT(viewz)) / 21.0f;
+		float lightstart, lightend;
+
+		lightend = (iz + ds_sz.x*width) * planelightfloat;
+		lightstart = iz * planelightfloat;
+
+		R_CalcTiltedLighting(FLOAT_TO_FIXED(lightstart), FLOAT_TO_FIXED(lightend));
+		//CONS_Printf("tilted lighting %f to %f (foc %f)\n", lightstart, lightend, focallengthf);
+	}
+
+	uz = ds_su.z + ds_su.y*(centery-ds_y) + ds_su.x*(ds_x1-centerx);
+	vz = ds_sv.z + ds_sv.y*(centery-ds_y) + ds_sv.x*(ds_x1-centerx);
+
+	dest = ylookup[ds_y] + columnofs[ds_x1];
+	source = ds_source;
+	//colormap = ds_colormap;
+
+#if 0	// The "perfect" reference version of this routine. Pretty slow.
+		// Use it only to see how things are supposed to look.
+	i = 0;
+	do
+	{
+		double z = 1.f/iz;
+		u = (INT64)(uz*z) + viewx;
+		v = (INT64)(vz*z) + viewy;
+
+		colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+
+		*dest = colormap[*(ds_transmap + (source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)] << 8) + dest[0])];
+		dest++;
+		iz += ds_sz.x;
+		uz += ds_su.x;
+		vz += ds_sv.x;
+	} while (--width >= 0);
+#else
+#define SPANSIZE 16
+#define INVSPAN	0.0625f
+
+	double startz = 1.f/iz;
+	double startu = uz*startz;
+	double startv = vz*startz;
+	double izstep, uzstep, vzstep;
+
+	izstep = ds_sz.x * SPANSIZE;
+	uzstep = ds_su.x * SPANSIZE;
+	vzstep = ds_sv.x * SPANSIZE;
+	//x1 = 0;
+	width++;
+
+	while (width >= SPANSIZE)
+	{
+		iz += izstep;
+		uz += uzstep;
+		vz += vzstep;
+
+		double endz = 1.f/iz;
+		double endu = uz*endz;
+		double endv = vz*endz;
+		UINT32 stepu = (INT64)((endu - startu) * INVSPAN);
+		UINT32 stepv = (INT64)((endv - startv) * INVSPAN);
+		u = (INT64)(startu) + viewx;
+		v = (INT64)(startv) + viewy;
+
+		for (i = SPANSIZE-1; i >= 0; i--)
+		{
+			colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+			*dest = colormap[*(ds_transmap + (source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)] << 8) + dest[0])];
+			dest++;
+			u += stepu;
+			v += stepv;
+		}
+		startu = endu;
+		startv = endv;
+		width -= SPANSIZE;
+	}
+	if (width > 0)
+	{
+		if (width == 1)
+		{
+			u = (INT64)(startu);
+			v = (INT64)(startv);
+			colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+			*dest = colormap[*(ds_transmap + (source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)] << 8) + dest[0])];
+		}
+		else
+		{
+			double left = width;
+			iz += ds_sz.x * left;
+			uz += ds_su.x * left;
+			vz += ds_sv.x * left;
+
+			double endz = 1.f/iz;
+			double endu = uz*endz;
+			double endv = vz*endz;
+			left = 1.f/left;
+			UINT32 stepu = (INT64)((endu - startu) * left);
+			UINT32 stepv = (INT64)((endv - startv) * left);
+			u = (INT64)(startu) + viewx;
+			v = (INT64)(startv) + viewy;
+
+			for (; width != 0; width--)
+			{
+				colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+				*dest = colormap[*(ds_transmap + (source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)] << 8) + dest[0])];
+				dest++;
+				u += stepu;
+				v += stepv;
+			}
+		}
+	}
+#endif
+}
+
+void R_DrawTiltedSplat_8(void)
+{
+	// x1, x2 = ds_x1, ds_x2
+	int width = ds_x2 - ds_x1;
+	double iz, uz, vz;
+	UINT32 u, v;
+	int i;
+
+	UINT8 *source;
+	UINT8 *colormap;
+	UINT8 *dest;
+
+	UINT8 val;
+
+	iz = ds_sz.z + ds_sz.y*(centery-ds_y) + ds_sz.x*(ds_x1-centerx);
+
+	// Lighting is simple. It's just linear interpolation from start to end
+	{
+		float planelightfloat = BASEVIDWIDTH*BASEVIDWIDTH/vid.width / (zeroheight - FIXED_TO_FLOAT(viewz)) / 21.0f;
+		float lightstart, lightend;
+
+		lightend = (iz + ds_sz.x*width) * planelightfloat;
+		lightstart = iz * planelightfloat;
+
+		R_CalcTiltedLighting(FLOAT_TO_FIXED(lightstart), FLOAT_TO_FIXED(lightend));
+		//CONS_Printf("tilted lighting %f to %f (foc %f)\n", lightstart, lightend, focallengthf);
+	}
+
+	uz = ds_su.z + ds_su.y*(centery-ds_y) + ds_su.x*(ds_x1-centerx);
+	vz = ds_sv.z + ds_sv.y*(centery-ds_y) + ds_sv.x*(ds_x1-centerx);
+
+	dest = ylookup[ds_y] + columnofs[ds_x1];
+	source = ds_source;
+	//colormap = ds_colormap;
+
+#if 0	// The "perfect" reference version of this routine. Pretty slow.
+		// Use it only to see how things are supposed to look.
+	i = 0;
+	do
+	{
+		double z = 1.f/iz;
+		u = (INT64)(uz*z) + viewx;
+		v = (INT64)(vz*z) + viewy;
+
+		colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+
+		val = colormap[source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)]];
+		if (val != TRANSPARENTPIXEL)
+			*dest = val;
+		dest++;
+		iz += ds_sz.x;
+		uz += ds_su.x;
+		vz += ds_sv.x;
+	} while (--width >= 0);
+#else
+#define SPANSIZE 16
+#define INVSPAN	0.0625f
+
+	double startz = 1.f/iz;
+	double startu = uz*startz;
+	double startv = vz*startz;
+	double izstep, uzstep, vzstep;
+
+	izstep = ds_sz.x * SPANSIZE;
+	uzstep = ds_su.x * SPANSIZE;
+	vzstep = ds_sv.x * SPANSIZE;
+	//x1 = 0;
+	width++;
+
+	while (width >= SPANSIZE)
+	{
+		iz += izstep;
+		uz += uzstep;
+		vz += vzstep;
+
+		double endz = 1.f/iz;
+		double endu = uz*endz;
+		double endv = vz*endz;
+		UINT32 stepu = (INT64)((endu - startu) * INVSPAN);
+		UINT32 stepv = (INT64)((endv - startv) * INVSPAN);
+		u = (INT64)(startu) + viewx;
+		v = (INT64)(startv) + viewy;
+
+		for (i = SPANSIZE-1; i >= 0; i--)
+		{
+			colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+			val = colormap[source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)]];
+			if (val != TRANSPARENTPIXEL)
+				*dest = val;
+			dest++;
+			u += stepu;
+			v += stepv;
+		}
+		startu = endu;
+		startv = endv;
+		width -= SPANSIZE;
+	}
+	if (width > 0)
+	{
+		if (width == 1)
+		{
+			u = (INT64)(startu);
+			v = (INT64)(startv);
+			colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+			val = colormap[source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)]];
+			if (val != TRANSPARENTPIXEL)
+				*dest = val;
+		}
+		else
+		{
+			double left = width;
+			iz += ds_sz.x * left;
+			uz += ds_su.x * left;
+			vz += ds_sv.x * left;
+
+			double endz = 1.f/iz;
+			double endu = uz*endz;
+			double endv = vz*endz;
+			left = 1.f/left;
+			UINT32 stepu = (INT64)((endu - startu) * left);
+			UINT32 stepv = (INT64)((endv - startv) * left);
+			u = (INT64)(startu) + viewx;
+			v = (INT64)(startv) + viewy;
+
+			for (; width != 0; width--)
+			{
+				colormap = planezlight[tiltlighting[ds_x1++]] + (ds_colormap - colormaps);
+				val = colormap[source[((v >> nflatyshift) & nflatmask) | (u >> nflatxshift)]];
+				if (val != TRANSPARENTPIXEL)
+					*dest = val;
+				dest++;
+				u += stepu;
+				v += stepv;
+			}
+		}
+	}
+#endif
+}
+#endif // ESLOPE
+
 /**	\brief The R_DrawSplat_8 function
 	Just like R_DrawSpan_8, but skips transparent pixels.
 */

src/r_main.c

@@ -527,6 +527,8 @@ static void R_InitTextureMapping(void)
 	focallength = FixedDiv(centerxfrac,
 		FINETANGENT(FINEANGLES/4+/*cv_fov.value*/ FIELDOFVIEW/2));
 
+	focallengthf = FIXED_TO_FLOAT(focallength);
+
 	for (i = 0; i < FINEANGLES/2; i++)
 	{
 		if (FINETANGENT(i) > FRACUNIT*2)

src/r_plane.c

@@ -74,7 +74,7 @@ static INT32 spanstart[MAXVIDHEIGHT];
 //
 // texture mapping
 //
-static lighttable_t **planezlight;
+lighttable_t **planezlight;
 static fixed_t planeheight;
 
 //added : 10-02-98: yslopetab is what yslope used to be,
@@ -327,6 +327,11 @@ void R_MapPlane(INT32 y, INT32 x1, INT32 x2)
 	if (pindex >= MAXLIGHTZ)
 		pindex = MAXLIGHTZ - 1;
 
+#ifdef ESLOPE
+	if (currentplane->slope)
+		ds_colormap = colormaps;
+	else
+#endif
 	ds_colormap = planezlight[pindex];
 
 	if (currentplane->extra_colormap)
@@ -423,11 +428,18 @@ static visplane_t *new_visplane(unsigned hash)
 //
 visplane_t *R_FindPlane(fixed_t height, INT32 picnum, INT32 lightlevel,
 	fixed_t xoff, fixed_t yoff, angle_t plangle, extracolormap_t *planecolormap,
-	ffloor_t *pfloor)
+	ffloor_t *pfloor
+#ifdef ESLOPE
+			, pslope_t *slope
+#endif
+			)
 {
 	visplane_t *check;
 	unsigned hash;
 
+#ifdef ESLOPE
+	if (slope); else // Don't mess with this right now if a slope is involved
+#endif
 	if (plangle != 0)
 	{
 		// Add the view offset, rotated by the plane angle.
@@ -462,7 +474,11 @@ visplane_t *R_FindPlane(fixed_t height, INT32 picnum, INT32 lightlevel,
 			&& xoff == check->xoffs && yoff == check->yoffs
 			&& planecolormap == check->extra_colormap
 			&& !pfloor && !check->ffloor && check->viewz == viewz
-			&& check->viewangle == viewangle)
+			&& check->viewangle == viewangle
+#ifdef ESLOPE
+			&& check->slope == slope
+#endif
+			)
 		{
 			return check;
 		}
@@ -485,6 +501,9 @@ visplane_t *R_FindPlane(fixed_t height, INT32 picnum, INT32 lightlevel,
 #ifdef POLYOBJECTS_PLANES
 	check->polyobj = NULL;
 #endif
+#ifdef ESLOPE
+	check->slope = slope;
+#endif
 
 	memset(check->top, 0xff, sizeof (check->top));
 	memset(check->bottom, 0x00, sizeof (check->bottom));
@@ -551,6 +570,9 @@ visplane_t *R_CheckPlane(visplane_t *pl, INT32 start, INT32 stop)
 		new_pl->plangle = pl->plangle;
 #ifdef POLYOBJECTS_PLANES
 		new_pl->polyobj = pl->polyobj;
+#endif
+#ifdef ESLOPE
+		new_pl->slope = pl->slope;
 #endif
 		pl = new_pl;
 		pl->minx = start;
@@ -814,7 +836,11 @@ void R_DrawSinglePlane(visplane_t *pl)
 		else light = (pl->lightlevel >> LIGHTSEGSHIFT);
 
 #ifndef NOWATER
-		if (pl->ffloor->flags & FF_RIPPLE)
+		if (pl->ffloor->flags & FF_RIPPLE
+#ifdef ESLOPE
+				&& !pl->slope
+#endif
+			)
 		{
 			INT32 top, bottom;
 
@@ -842,6 +868,9 @@ void R_DrawSinglePlane(visplane_t *pl)
 	}
 	else light = (pl->lightlevel >> LIGHTSEGSHIFT);
 
+#ifdef ESLOPE
+	if (!pl->slope) // Don't mess with angle on slopes! We'll handle this ourselves later
+#endif
 	if (viewangle != pl->viewangle)
 	{
 		memset(cachedheight, 0, sizeof (cachedheight));
@@ -915,6 +944,99 @@ void R_DrawSinglePlane(visplane_t *pl)
 	if (light < 0)
 		light = 0;
 
+#ifdef ESLOPE
+	if (pl->slope) {
+		// Potentially override other stuff for now cus we're mean. :< But draw a slope plane!
+		// I copied ZDoom's code and adapted it to SRB2... -Red
+		floatv3_t p, m, n;
+		float ang;
+		float vx, vy, vz;
+		float fudge;
+
+		xoffs &= ((1 << (32-nflatshiftup))-1);
+		yoffs &= ((1 << (32-nflatshiftup))-1);
+
+		xoffs -= (pl->slope->o.x + (1 << (31-nflatshiftup))) & ~((1 << (32-nflatshiftup))-1);
+		yoffs += (pl->slope->o.y + (1 << (31-nflatshiftup))) & ~((1 << (32-nflatshiftup))-1);
+
+		// Okay, look, don't ask me why this works, but without this setup there's a disgusting-looking misalignment with the textures. -Red
+		fudge = ((1<<nflatshiftup)+1.0f)/(1<<nflatshiftup);
+
+		xoffs *= fudge;
+		yoffs /= fudge;
+
+		vx = FIXED_TO_FLOAT(viewx+xoffs);
+		vy = FIXED_TO_FLOAT(viewy-yoffs);
+		vz = FIXED_TO_FLOAT(viewz);
+
+		zeroheight = FIXED_TO_FLOAT(P_GetZAt(pl->slope, viewx, viewy));
+
+#define ANG2RAD(angle) ((float)((angle)*M_PI)/ANGLE_180)
+
+		// p is the texture origin in view space
+		// Don't add in the offsets at this stage, because doing so can result in
+		// errors if the flat is rotated.
+		ang = ANG2RAD(ANGLE_270 - viewangle);
+		p.x = vx * cos(ang) - vy * sin(ang);
+		p.z = vx * sin(ang) + vy * cos(ang);
+		p.y = FIXED_TO_FLOAT(P_GetZAt(pl->slope, -xoffs, yoffs)) - vz;
+
+		// m is the v direction vector in view space
+		ang = ANG2RAD(ANGLE_180 - viewangle - pl->plangle);
+		m.x = cos(ang);
+		m.z = sin(ang);
+
+		// n is the u direction vector in view space
+		n.x = sin(ang);
+		n.z = -cos(ang);
+
+		ang = ANG2RAD(pl->plangle);
+		m.y = FIXED_TO_FLOAT(P_GetZAt(pl->slope, viewx + FLOAT_TO_FIXED(sin(ang)), viewy + FLOAT_TO_FIXED(cos(ang)))) - zeroheight;
+		n.y = FIXED_TO_FLOAT(P_GetZAt(pl->slope, viewx + FLOAT_TO_FIXED(cos(ang)), viewy - FLOAT_TO_FIXED(sin(ang)))) - zeroheight;
+
+		m.x /= fudge;
+		m.y /= fudge;
+		m.z /= fudge;
+
+		n.x *= fudge;
+		n.y *= fudge;
+		n.z *= fudge;
+
+		// Eh. I tried making this stuff fixed-point and it exploded on me. Here's a macro for the only floating-point vector function I recall using.
+#define CROSS(d, v1, v2) \
+   d.x = (v1.y * v2.z) - (v1.z * v2.y);\
+   d.y = (v1.z * v2.x) - (v1.x * v2.z);\
+   d.z = (v1.x * v2.y) - (v1.y * v2.x)
+		CROSS(ds_su, p, m);
+		CROSS(ds_sv, p, n);
+		CROSS(ds_sz, m, n);
+#undef CROSS
+
+		ds_su.z *= focallengthf;
+		ds_sv.z *= focallengthf;
+		ds_sz.z *= focallengthf;
+
+		// Premultiply the texture vectors with the scale factors
+#define SFMULT 65536.f*(1<<nflatshiftup)
+		ds_su.x *= SFMULT;
+		ds_su.y *= SFMULT;
+		ds_su.z *= SFMULT;
+		ds_sv.x *= SFMULT;
+		ds_sv.y *= SFMULT;
+		ds_sv.z *= SFMULT;
+#undef SFMULT
+
+		if (spanfunc == R_DrawTranslucentSpan_8)
+			spanfunc = R_DrawTiltedTranslucentSpan_8;
+		else if (spanfunc == splatfunc)
+			spanfunc = R_DrawTiltedSplat_8;
+		else
+			spanfunc = R_DrawTiltedSpan_8;
+
+		planezlight = scalelight[light];
+	} else
+#endif // ESLOPE
+
 	planezlight = zlight[light];
 
 	// set the maximum value for unsigned

src/r_plane.h

@@ -61,6 +61,9 @@ typedef struct visplane_s
 #ifdef POLYOBJECTS_PLANES
 	polyobj_t *polyobj;
 #endif
+#ifdef ESLOPE
+	pslope_t *slope;
+#endif
 } visplane_t;
 
 extern visplane_t *floorplane;
@@ -79,6 +82,8 @@ extern fixed_t cachedxstep[MAXVIDHEIGHT];
 extern fixed_t cachedystep[MAXVIDHEIGHT];
 extern fixed_t basexscale, baseyscale;
 
+extern lighttable_t **planezlight;
+
 extern fixed_t *yslope;
 extern fixed_t distscale[MAXVIDWIDTH];
 
@@ -91,7 +96,11 @@ void R_MapPlane(INT32 y, INT32 x1, INT32 x2);
 void R_MakeSpans(INT32 x, INT32 t1, INT32 b1, INT32 t2, INT32 b2);
 void R_DrawPlanes(void);
 visplane_t *R_FindPlane(fixed_t height, INT32 picnum, INT32 lightlevel, fixed_t xoff, fixed_t yoff, angle_t plangle,
-	extracolormap_t *planecolormap, ffloor_t *ffloor);
+	extracolormap_t *planecolormap, ffloor_t *ffloor
+#ifdef ESLOPE
+	, pslope_t *slope
+#endif
+	);
 visplane_t *R_CheckPlane(visplane_t *pl, INT32 start, INT32 stop);
 void R_ExpandPlane(visplane_t *pl, INT32 start, INT32 stop);
 void R_PlaneBounds(visplane_t *plane);
@@ -110,6 +119,14 @@ typedef struct planemgr_s
 	INT16 f_clip[MAXVIDWIDTH];
 	INT16 c_clip[MAXVIDWIDTH];
 
+#ifdef ESLOPE
+	// For slope rendering; the height at the other end
+	fixed_t f_pos_slope;
+	fixed_t b_pos_slope;
+
+	struct pslope_s *slope;
+#endif
+
 	struct ffloor_s *ffloor;
 #ifdef POLYOBJECTS_PLANES
 	polyobj_t *polyobj;

src/r_things.c

@@ -954,12 +954,22 @@ static void R_SplitSprite(vissprite_t *sprite, mobj_t *thing)
 
 	for (i = 1; i < sector->numlights; i++)
 	{
-		if (sector->lightlist[i].height >= sprite->gzt || !(sector->lightlist[i].caster->flags & FF_CUTSPRITES))
+		fixed_t testheight = sector->lightlist[i].height;
+
+		if (!(sector->lightlist[i].caster->flags & FF_CUTSPRITES))
 			continue;
-		if (sector->lightlist[i].height <= sprite->gz)
+
+#ifdef ESLOPE
+		if (sector->lightlist[i].slope)
+			testheight = P_GetZAt(sector->lightlist[i].slope, sprite->gx, sprite->gy);
+#endif
+
+		if (testheight >= sprite->gzt)
+			continue;
+		if (testheight <= sprite->gz)
 			return;
 
-		cutfrac = (INT16)((centeryfrac - FixedMul(sector->lightlist[i].height - viewz, sprite->scale))>>FRACBITS);
+		cutfrac = (INT16)((centeryfrac - FixedMul(testheight - viewz, sprite->scale))>>FRACBITS);
 		if (cutfrac < 0)
 			continue;
 		if (cutfrac > vid.height)
@@ -970,15 +980,15 @@ static void R_SplitSprite(vissprite_t *sprite, mobj_t *thing)
 		newsprite = M_Memcpy(R_NewVisSprite(), sprite, sizeof (vissprite_t));
 
 		sprite->cut |= SC_BOTTOM;
-		sprite->gz = sector->lightlist[i].height;
+		sprite->gz = testheight;
 
 		newsprite->gzt = sprite->gz;
 
 		sprite->sz = cutfrac;
 		newsprite->szt = (INT16)(sprite->sz - 1);
 
-		if (sector->lightlist[i].height < sprite->pzt && sector->lightlist[i].height > sprite->pz)
-			sprite->pz = newsprite->pzt = sector->lightlist[i].height;
+		if (testheight < sprite->pzt && testheight > sprite->pz)
+			sprite->pz = newsprite->pzt = testheight;
 		else
 		{
 			newsprite->pz = newsprite->gz;
@@ -1200,7 +1210,20 @@ static void R_ProjectSprite(mobj_t *thing)
 	if (thing->subsector->sector->numlights)
 	{
 		INT32 lightnum;
+#ifdef ESLOPE // R_GetPlaneLight won't work on sloped lights!
+		light = thing->subsector->sector->numlights - 1;
+
+		for (lightnum = 1; lightnum < thing->subsector->sector->numlights; lightnum++) {
+			fixed_t h = thing->subsector->sector->lightlist[lightnum].slope ? P_GetZAt(thing->subsector->sector->lightlist[lightnum].slope, thing->x, thing->y)
+			            : thing->subsector->sector->lightlist[lightnum].height;
+			if (h <= gzt) {
+				light = lightnum - 1;
+				break;
+			}
+		}
+#else
 		light = R_GetPlaneLight(thing->subsector->sector, gzt, false);
+#endif
 		lightnum = (*thing->subsector->sector->lightlist[light].lightlevel >> LIGHTSEGSHIFT);
 
 		if (lightnum < 0)
@@ -1761,24 +1784,34 @@ static void R_CreateDrawNodes(void)
 		{
 			if (r2->plane)
 			{
+				fixed_t planeobjectz, planecameraz;
 				if (r2->plane->minx > rover->x2 || r2->plane->maxx < rover->x1)
 					continue;
 				if (rover->szt > r2->plane->low || rover->sz < r2->plane->high)
 					continue;
 
+#ifdef ESLOPE
+				// Effective height may be different for each comparison in the case of slopes
+				if (r2->plane->slope) {
+					planeobjectz = P_GetZAt(r2->plane->slope, rover->gx, rover->gy);
+					planecameraz = P_GetZAt(r2->plane->slope, viewx, viewy);
+				} else
+#endif
+					planeobjectz = planecameraz = r2->plane->height;
+
 				if (rover->mobjflags & MF_NOCLIPHEIGHT)
 				{
 					//Objects with NOCLIPHEIGHT can appear halfway in.
-					if (r2->plane->height < viewz && rover->pz+(rover->thingheight/2) >= r2->plane->height)
+					if (planecameraz < viewz && rover->pz+(rover->thingheight/2) >= planeobjectz)
 						continue;
-					if (r2->plane->height > viewz && rover->pzt-(rover->thingheight/2) <= r2->plane->height)
+					if (planecameraz > viewz && rover->pzt-(rover->thingheight/2) <= planeobjectz)
 						continue;
 				}
 				else
 				{
-					if (r2->plane->height < viewz && rover->pz >= r2->plane->height)
+					if (planecameraz < viewz && rover->pz >= planeobjectz)
 						continue;
-					if (r2->plane->height > viewz && rover->pzt <= r2->plane->height)
+					if (planecameraz > viewz && rover->pzt <= planeobjectz)
 						continue;
 				}
 
@@ -1808,6 +1841,7 @@ static void R_CreateDrawNodes(void)
 			}
 			else if (r2->thickseg)
 			{
+				fixed_t topplaneobjectz, topplanecameraz, botplaneobjectz, botplanecameraz;
 				if (rover->x1 > r2->thickseg->x2 || rover->x2 < r2->thickseg->x1)
 					continue;
 
@@ -1818,9 +1852,25 @@ static void R_CreateDrawNodes(void)
 				if (scale <= rover->scale)
 					continue;
 
-				if ((*r2->ffloor->topheight > viewz && *r2->ffloor->bottomheight < viewz) ||
-				    (*r2->ffloor->topheight < viewz && rover->gzt < *r2->ffloor->topheight) ||
-				    (*r2->ffloor->bottomheight > viewz && rover->gz > *r2->ffloor->bottomheight))
+#ifdef ESLOPE
+				if (*r2->ffloor->t_slope) {
+					topplaneobjectz = P_GetZAt(*r2->ffloor->t_slope, rover->gx, rover->gy);
+					topplanecameraz = P_GetZAt(*r2->ffloor->t_slope, viewx, viewy);
+				} else
+#endif
+					topplaneobjectz = topplanecameraz = *r2->ffloor->topheight;
+
+#ifdef ESLOPE
+				if (*r2->ffloor->b_slope) {
+					botplaneobjectz = P_GetZAt(*r2->ffloor->b_slope, rover->gx, rover->gy);
+					botplanecameraz = P_GetZAt(*r2->ffloor->b_slope, viewx, viewy);
+				} else
+#endif
+					botplaneobjectz = botplanecameraz = *r2->ffloor->bottomheight;
+
+				if ((topplanecameraz > viewz && botplanecameraz < viewz) ||
+				    (topplanecameraz < viewz && rover->gzt < topplaneobjectz) ||
+				    (botplanecameraz > viewz && rover->gz > botplaneobjectz))
 				{
 					entry = R_CreateDrawNode(NULL);
 					(entry->prev = r2->prev)->next = entry;
@@ -2039,21 +2089,21 @@ void R_ClipSprites(void)
 			if (spr->gzt <= ds->tsilheight)
 				silhouette &= ~SIL_TOP;
 
-			if (silhouette == 1)
+			if (silhouette == SIL_BOTTOM)
 			{
 				// bottom sil
 				for (x = r1; x <= r2; x++)
 					if (spr->clipbot[x] == -2)
 						spr->clipbot[x] = ds->sprbottomclip[x];
 			}
-			else if (silhouette == 2)
+			else if (silhouette == SIL_TOP)
 			{
 				// top sil
 				for (x = r1; x <= r2; x++)
 					if (spr->cliptop[x] == -2)
 						spr->cliptop[x] = ds->sprtopclip[x];
 			}
-			else if (silhouette == 3)
+			else if (silhouette == (SIL_TOP|SIL_BOTTOM))
 			{
 				// both
 				for (x = r1; x <= r2; x++)

src/tables.c

@@ -2225,9 +2225,6 @@ angle_t tantoangle[2049] =
 	536870912
 };
 
-
-#ifdef NEED_FIXED_VECTOR
-
 static angle_t fineacon[65536*2] = {
 	  ANGLE_MAX, 2143707442, 2142143280, 2140943052, 2139931208, 2139039753, 2138233813, 2137492672, 2136802831, 2136154917, 2135542102, 2134959233, 2134402306, 2133868139, 2133354148, 2132858208,
 	 2132378539, 2131913638, 2131462220, 2131023174, 2130595537, 2130178462, 2129771202, 2129373097, 2128983555, 2128602046, 2128228092, 2127861261, 2127501162, 2127147436, 2126799757, 2126457825,
@@ -10706,5 +10703,3 @@ void FM_Rotate(matrix_t *dest, angle_t angle, fixed_t x, fixed_t y, fixed_t z)
 	M(3, 3) = FRACUNIT;
 #undef M
 }
-
-#endif

src/tables.h

@@ -96,9 +96,6 @@ FUNCMATH angle_t FixedAngle(fixed_t fa);
 // and with a factor, with +factor for (fa/factor) and -factor for (fa*factor)
 FUNCMATH angle_t FixedAngleC(fixed_t fa, fixed_t factor);
 
-
-#ifdef NEED_FIXED_VECTOR
-
 /// The FixedAcos function
 FUNCMATH angle_t FixedAcos(fixed_t x);
 
@@ -112,8 +109,6 @@ void FV3_Rotate(vector3_t *rotVec, const vector3_t *axisVec, const angle_t angle
 /// Fixed Point Matrix functions
 void FM_Rotate(matrix_t *dest, angle_t angle, fixed_t x, fixed_t y, fixed_t z);
 
-#endif // defined NEED_FIXED_VECTOR
-
 // The table values in tables.c are calculated with this many fractional bits.
 #define FINE_FRACBITS 16
 

tools/anglechk.c

@@ -351,6 +351,13 @@ int main(int argc, char** argv)
 	return 0;
 }
 
+static void *cpu_cpy(void *dest, const void *src, size_t n)
+{
+	return memcpy(dest, src, n);
+}
+
+void *(*M_Memcpy)(void* dest, const void* src, size_t n) = cpu_cpy;
+
 void I_Error(const char *error, ...)
 {
 	(void)error;