Implement UDMF clipmidtex

src/deh_tables.c

@@ -4540,6 +4540,7 @@ const char *const ML_LIST[] = {
 	"EFFECT6",
 	"BOUNCY",
 	"TFERLINE",
+	"CLIPMIDTEX",
 	NULL
 };
 

src/doomdata.h

@@ -146,7 +146,9 @@ enum
 	// Bounce off walls!
 	ML_BOUNCY        = 1<<14,
 
-	ML_TFERLINE      = 1<<15
+	ML_TFERLINE      = 1<<15,
+
+	ML_CLIPMIDTEX    = 1<<16
 };
 
 // Sector definition, from editing.

src/hardware/hw_main.c

@@ -1159,10 +1159,20 @@ static void HWR_RenderMidtexture(INT32 gl_midtexture, float cliplow, float cliph
 	}
 
 	// The cut-off values of a linedef can always be constant, since every line has an absoulute front and or back sector
-	lowcut = popenbottom;
-	highcut = popentop;
-	lowcutslope = popenbottomslope;
-	highcutslope = popentopslope;
+	if (gl_curline->polyseg && !(gl_linedef->flags & ML_CLIPMIDTEX))
+	{
+		lowcut = polybottom;
+		highcut = polytop;
+		lowcutslope = polybottomslope;
+		highcutslope = polytopslope;
+	}
+	else
+	{
+		lowcut = popenbottom;
+		highcut = popentop;
+		lowcutslope = popenbottomslope;
+		highcutslope = popentopslope;
+	}
 
 	fixed_t h = min(highcut, polytop);
 	fixed_t l = max(polybottom, lowcut);

src/p_saveg.c

@@ -1571,7 +1571,7 @@ static void ArchiveLines(void)
 			if (diff & LD_DIFF2)
 				WRITEUINT8(save_p, diff2);
 			if (diff & LD_FLAG)
-				WRITEINT16(save_p, li->flags);
+				WRITEUINT32(save_p, li->flags);
 			if (diff & LD_SPECIAL)
 				WRITEINT16(save_p, li->special);
 			if (diff & LD_CLLCOUNT)
@@ -1705,7 +1705,7 @@ static void UnArchiveLines(void)
 		li = &lines[i];
 
 		if (diff & LD_FLAG)
-			li->flags = READINT16(save_p);
+			li->flags = READUINT32(save_p);
 		if (diff & LD_SPECIAL)
 			li->special = READINT16(save_p);
 		if (diff & LD_CLLCOUNT)

src/p_setup.c

@@ -1963,8 +1963,7 @@ static void ParseTextmapSidedefParameter(UINT32 i, const char *param, const char
 		P_SetSidedefSector(i, atol(val));
 	else if (fastcmp(param, "repeatcnt"))
 		sides[i].repeatcnt = atol(val);
-	// Oh God there's a total of 28 fields to read. Uhhh
-	// Okay, so ParseTextmapSidedefOverlay handles all the parameters edges have.
+	// Parse edge fields
 	else if (fastncmp(param, "edge_", 5) && strlen(param) > 5)
 	{
 		if (fastncmp(param, "edge_top_upper_", 15) && strlen(param) > 15)
@@ -2058,6 +2057,8 @@ static void ParseTextmapLinedefParameter(UINT32 i, const char *param, const char
 		lines[i].flags |= ML_MIDPEG;
 	else if (fastcmp(param, "midsolid") && fastcmp("true", val))
 		lines[i].flags |= ML_MIDSOLID;
+	else if (fastcmp(param, "clipmidtex") && fastcmp("true", val))
+		lines[i].flags |= ML_CLIPMIDTEX;
 	else if (fastcmp(param, "wrapmidtex") && fastcmp("true", val))
 		lines[i].flags |= ML_WRAPMIDTEX;
 	else if (fastcmp(param, "nonet") && fastcmp("true", val))

src/r_defs.h

@@ -579,8 +579,7 @@ typedef struct line_s
 	fixed_t dx, dy; // Precalculated v2 - v1 for side checking.
 	angle_t angle; // Precalculated angle between dx and dy
 
-	// Animation related.
-	INT16 flags;
+	UINT32 flags;
 	INT16 special;
 	taglist_t tags;
 	INT32 args[NUMLINEARGS];

src/r_segs.c

@@ -565,6 +565,33 @@ void R_RenderMaskedSegRange(drawseg_t *ds, INT32 x1, INT32 x2)
 
 	for (times = 0; times < repeats; times++)
 	{
+		fixed_t left_top = 0, left_bottom = 0;
+		fixed_t right_top = 0, right_bottom = 0;
+		fixed_t top_step = 0, bottom_step = 0;
+
+		// Get left and right ends of wall for clipping it
+		if (ldef->flags & ML_CLIPMIDTEX)
+		{
+			// For this to work correctly with polyobjects, it needs to use its own back sector, rather than the seg's front sector
+			sector_t *sec_front = curline->polyseg ?
+				curline->polyseg->lines[0]->backsector :
+				frontsector;
+
+			// calculate both left ends
+			left_top    = P_GetSectorCeilingZAt(sec_front, ds->leftpos.x, ds->leftpos.y) - viewz;
+			left_bottom = P_GetSectorFloorZAt(sec_front, ds->leftpos.x, ds->leftpos.y) - viewz;
+
+			// calculate right ends now
+			right_top    = P_GetSectorCeilingZAt(sec_front, ds->rightpos.x, ds->rightpos.y) - viewz;
+			right_bottom = P_GetSectorFloorZAt(sec_front, ds->rightpos.x, ds->rightpos.y) - viewz;
+
+			top_step = (right_top - left_top) / range;
+			bottom_step = (right_bottom - left_bottom) / range;
+
+			left_top += top_step * (x1 - ds->x1);
+			left_bottom += bottom_step * (x1 - ds->x1);
+		}
+
 		if (times > 0)
 		{
 			rw_scalestep = scalestep;
@@ -585,7 +612,7 @@ void R_RenderMaskedSegRange(drawseg_t *ds, INT32 x1, INT32 x2)
 		{
 			dc_texturemid = ds->maskedtextureheight[dc_x];
 
-			if (curline->linedef->flags & ML_MIDPEG)
+			if (ldef->flags & ML_MIDPEG)
 				dc_texturemid += (textureheight[texnum])*times + textureheight[texnum];
 			else
 				dc_texturemid -= (textureheight[texnum])*times;
@@ -614,16 +641,18 @@ void R_RenderMaskedSegRange(drawseg_t *ds, INT32 x1, INT32 x2)
 			texture_top = dc_texturemid;
 			texture_bottom = texture_top - textureheight[texnum];
 
-			sprtopscreen = centeryfrac - FixedMul(texture_top, spryscale);
-
-			// Clip texture if it's a polyobject side
-			if (curline->polyseg)
+			// If the texture is meant to be clipped
+			if (ldef->flags & ML_CLIPMIDTEX)
 			{
-				// For this to work correctly, it needs to use the polyobject's sector, rather than the seg's back sector
-				// Change this when polyobjects support slopes
-				texture_bottom = max(curline->polyseg->lines[0]->backsector->floorheight - viewz, texture_bottom);
+				texture_top = min(left_top, texture_top);
+				texture_bottom = max(left_bottom, texture_bottom);
+
+				left_top += top_step;
+				left_bottom += bottom_step;
 			}
 
+			sprtopscreen = centeryfrac - FixedMul(texture_top, spryscale);
+
 			// set wall bounds if there is a light list, or if this is a polyobject side
 			if (dc_numlights || curline->polyseg)
 			{