- float version of clipmove's slope sprite collector.

This could be simplified quite a bit by leveraging the info returned by GetFlatSpritePosition.

source/build/src/clip.cpp

@@ -248,17 +248,12 @@ CollisionBase clipmove_(vec3_t * const pos, int * const sectnum, int32_t xvect,
         TSectIterator<DCoreActor> it(dasect);
         while (auto actor = it.Next())
         {
-            const int32_t cstat = actor->spr.cstat;
+            int cstat = actor->spr.cstat;
 
             if (actor->spr.cstat2 & CSTAT2_SPRITE_NOFIND) continue;
-            if ((cstat&dasprclipmask) == 0)
+            if ((cstat & dasprclipmask) == 0)
                 continue;
 
-            auto p1 = actor->int_pos().vec2;
-
-            CollisionBase obj;
-            obj.setSprite(actor);
-
             switch (cstat & (CSTAT_SPRITE_ALIGNMENT_MASK))
             {
             case CSTAT_SPRITE_ALIGNMENT_FACING:
@@ -274,63 +269,7 @@ CollisionBase clipmove_(vec3_t * const pos, int * const sectnum, int32_t xvect,
                 break;
 
             case CSTAT_SPRITE_ALIGNMENT_SLOPE:
-            {
+                processClipSlopeSprite(clip, actor);
-
-                if (!processClipFloorSprite(clip, actor)) continue;
-                int heinum = spriteGetSlope(actor);
-
-                if (heinum == 0) continue;
-
-                // the rest is for slope sprites only.
-                auto tex = TexMan.GetGameTexture(actor->spr.spritetexture());
-                const int32_t cosang = bcos(actor->int_ang());
-                const int32_t sinang = bsin(actor->int_ang());
-                vec2_t const span = { (int)tex->GetDisplayWidth(), (int)tex->GetDisplayHeight() };
-                vec2_t const repeat = { int(actor->spr.scale.X * scaletoint), int(actor->spr.scale.Y * scaletoint) };
-                vec2_t adjofs = { (int)tex->GetDisplayLeftOffset(), (int)tex->GetDisplayTopOffset() };
-
-                if (actor->spr.cstat & CSTAT_SPRITE_XFLIP)
-                    adjofs.X = -adjofs.X;
-
-                if (actor->spr.cstat & CSTAT_SPRITE_YFLIP)
-                    adjofs.Y = -adjofs.Y;
-
-                int32_t const centerx = ((span.X >> 1) + adjofs.X) * repeat.X;
-                int32_t const centery = ((span.Y >> 1) + adjofs.Y) * repeat.Y;
-                int32_t const rspanx = span.X * repeat.X;
-                int32_t const rspany = span.Y * repeat.Y;
-                int32_t const ratio = ksqrt(heinum * heinum + SLOPEVAL_FACTOR * SLOPEVAL_FACTOR);
-                int32_t zz[3] = { pos->Z, pos->Z + flordist, pos->Z - ceildist };
-                for (int k = 0; k < 3; k++)
-                {
-                    int32_t jj = DivScale(actor->int_pos().Z - zz[k], heinum, 18);
-                    int32_t jj2 = MulScale(jj, ratio, 12);
-                    if (jj2 > (centery << 8) || jj2 < ((centery - rspany) << 8))
-                        continue;
-                    int32_t x1 = actor->int_pos().X + MulScale(sinang, centerx, 16) + MulScale(jj, cosang, 24);
-                    int32_t y1 = actor->int_pos().Y - MulScale(cosang, centerx, 16) + MulScale(jj, sinang, 24);
-                    int32_t x2 = x1 - MulScale(sinang, rspanx, 16);
-                    int32_t y2 = y1 + MulScale(cosang, rspanx, 16);
-
-                    vec2_t const v = { MulScale(bcos(actor->int_ang() - 256), walldist, 14),
-                                       MulScale(bsin(actor->int_ang() - 256), walldist, 14) };
-
-                    if (clipinsideboxline(cent.X, cent.Y, x1, y1, x2, y2, rad) != 0)
-                    {
-                        if ((x1 - pos->X) * (y2 - pos->Y) >= (x2 - pos->X) * (y1 - pos->Y))
-                        {
-                            addclipline(x1 + v.X, y1 + v.Y, x2 + v.Y, y2 - v.X, obj, false);
-                        }
-                        else
-                        {
-		                    if ((cstat & CSTAT_SPRITE_ONE_SIDE) != 0)
-                                continue;
-                            addclipline(x2 - v.X, y2 - v.Y, x1 - v.Y, y1 + v.X, obj, false);
-                        }
-                    }
-                }
-                break;
-            }
             }
         }
     } while (clipsectcnt < clipsectnum || clipspritecnt < clipspritenum);

source/core/gamefuncs.cpp

@@ -1403,14 +1403,13 @@ void processClipWallSprite(MoveClipper& clip, DCoreActor* actor)
 	}
 
 }
-
 //==========================================================================
 //
 //
 //
 //==========================================================================
 
-bool processClipFloorSprite(MoveClipper& clip, DCoreActor* actor)
+bool processClipFloorSprite(MoveClipper& clip, DCoreActor* actor, DVector2* points, double* heights)
 {
 	int heinum = spriteGetSlope(actor);
 	double sprz = spriteGetZOfSlopef(&actor->spr, actor->spr.pos.XY(), heinum);
@@ -1422,8 +1421,9 @@ bool processClipFloorSprite(MoveClipper& clip, DCoreActor* actor)
 			if ((clip.pos.Z > sprz) == ((actor->spr.cstat & CSTAT_SPRITE_YFLIP) == 0)) return false;
 		}
 		
-		DVector2 points[4];
+		DVector2 opoints[4];
-		GetFlatSpritePosition(actor, actor->spr.pos.XY(), points, nullptr);
+		if (!points) points = opoints;
+		GetFlatSpritePosition(actor, actor->spr.pos.XY(), points, heights);
 
 		auto offset = (actor->spr.Angles.Yaw - DAngle45).ToVector() * clip.walldist;
 
@@ -1464,6 +1464,55 @@ bool processClipFloorSprite(MoveClipper& clip, DCoreActor* actor)
 //
 //==========================================================================
 
+void processClipSlopeSprite(MoveClipper& clip, DCoreActor* actor)
+{
+	auto spos = actor->spr.pos;
+	DVector2 points[4];
+	double heights[4];
+	DVector2 lpoints[2];
+
+	if (!processClipFloorSprite(clip, actor, points, heights)) return;
+	int heinum = spriteGetSlope(actor);
+	if (heinum == 0) return;
+
+	double zz[3] = { clip.pos.Z, clip.pos.Z + clip.floordist, clip.pos.Z - clip.ceilingdist };
+
+	CollisionBase objtype;
+	objtype.setSprite(actor);
+
+	for (int k = 0; k < 3; k++)
+	{
+		double factor = (zz[k] - heights[0]) / (heights[1] - heights[0]);
+		if (factor < 0 || factor > 1) continue;	// sprite never hits the desired height.
+		auto dist = (points[1] - points[0]) * factor;
+		lpoints[0] = points[0] + dist;
+		lpoints[1] = points[3] + dist;
+
+		// The rest is just the same as the main part of the wall sprite collector.
+		if (IsCloseToLine(clip.center, lpoints[0], lpoints[1], clip.movedist) == EClose::Outside) continue;	// out of reach
+
+		auto offset = (actor->spr.angle - DAngle45).ToVector() * clip.walldist;
+		auto d = lpoints[1] - lpoints[0];
+
+		if (PointOnLineSide(clip.center.X, clip.center.Y, lpoints[0].X, lpoints[0].Y, d.X, d.Y) <= 0)
+		{
+			// in front
+			addClipLine(clip, lpoints[0] + offset, lpoints[1] + offset.Rotated90CW(), objtype);
+		}
+		else if (!(actor->spr.cstat & CSTAT_SPRITE_ONE_SIDE))
+		{
+			// behind
+			addClipLine(clip, lpoints[0] - offset, lpoints[1] + offset.Rotated90CCW(), objtype);
+		}
+	}
+}
+
+//==========================================================================
+//
+//
+//
+//==========================================================================
+
 int FindBestSector(const DVector3& pos)
 {
 	int bestnum = -1;

source/core/gamefuncs.h

@@ -261,7 +261,8 @@ void processClipWalls(MoveClipper& clip, sectortype* sec);
 
 void processClipFaceSprite(MoveClipper& clip, DCoreActor* actor);
 void processClipWallSprite(MoveClipper& clip, DCoreActor* actor);
-bool processClipFloorSprite(MoveClipper& clip, DCoreActor* actor);
+bool processClipFloorSprite(MoveClipper& clip, DCoreActor* actor, DVector2* points = nullptr, double* heights = nullptr);
+void processClipSlopeSprite(MoveClipper& clip, DCoreActor* actor);
 int FindBestSector(const DVector3& pos);