Merge branch 'texture-fixes' into 'next'

Some texture-related fixes

Bugs fixed in this branch:
* upper/lower/middle textures with non-existent texture ids being capable of crashing the game. For instance, RVZ1 has colormap codes on non-colormap linedefs, which causes them to wind up with invalid texture ids because of how the game tries to interpret lower/upper textures with "#" followed by characters on normal linedefs. Fortunately these "textures" are normally not visible anyway (since they're all in control sectors) unless they are swapped with in-level textures by some crazy Lua script of some sort...
* animated single-patch textures with holes displaying garbage on first viewing (see this thread: https://mb.srb2.org/showthread.php?t=42195)
* the heights of the lighting (shadows or colormapping) from water/translucent/shadowcasting/etc FOFs become messed up when displayed on repeated midtextures.

See merge request !144

src/hardware/hw_main.c

@@ -1558,6 +1558,7 @@ static void HWR_StoreWallRange(double startfrac, double endfrac)
 
 	if (gr_backsector)
 	{
+		INT32 gr_toptexture, gr_bottomtexture;
 		// two sided line
 		if (gr_backsector->heightsec != -1)
 		{
@@ -1608,19 +1609,22 @@ static void HWR_StoreWallRange(double startfrac, double endfrac)
 #endif
 		}
 
+		gr_toptexture = R_GetTextureNum(gr_sidedef->toptexture);
+		gr_bottomtexture = R_GetTextureNum(gr_sidedef->bottomtexture);
+
 		// check TOP TEXTURE
 		if ((
 #ifdef ESLOPE
 			worldhighslope < worldtopslope ||
 #endif
             worldhigh < worldtop
-            ) && texturetranslation[gr_sidedef->toptexture])
+            ) && gr_toptexture)
 		{
 			if (drawtextured)
 			{
 				fixed_t texturevpegtop; // top
 
-				grTex = HWR_GetTexture(texturetranslation[gr_sidedef->toptexture]);
+				grTex = HWR_GetTexture(gr_toptexture);
 
 				// PEGGING
 				if (gr_linedef->flags & ML_DONTPEGTOP)
@@ -1638,7 +1642,7 @@ static void HWR_StoreWallRange(double startfrac, double endfrac)
 				texturevpegtop += gr_sidedef->rowoffset;
 
 				// This is so that it doesn't overflow and screw up the wall, it doesn't need to go higher than the texture's height anyway
-				texturevpegtop %= SHORT(textures[texturetranslation[gr_sidedef->toptexture]]->height)<<FRACBITS;
+				texturevpegtop %= SHORT(textures[gr_toptexture]->height)<<FRACBITS;
 
 				wallVerts[3].t = wallVerts[2].t = texturevpegtop * grTex->scaleY;
 				wallVerts[0].t = wallVerts[1].t = (texturevpegtop + gr_frontsector->ceilingheight - gr_backsector->ceilingheight) * grTex->scaleY;
@@ -1683,9 +1687,9 @@ static void HWR_StoreWallRange(double startfrac, double endfrac)
 #endif
 
 			if (gr_frontsector->numlights)
-				HWR_SplitWall(gr_frontsector, wallVerts, texturetranslation[gr_sidedef->toptexture], &Surf, FF_CUTSOLIDS);
+				HWR_SplitWall(gr_frontsector, wallVerts, gr_toptexture, &Surf, FF_CUTSOLIDS);
 			else if (grTex->mipmap.flags & TF_TRANSPARENT)
-				HWR_AddTransparentWall(wallVerts, &Surf, texturetranslation[gr_sidedef->toptexture], PF_Environment, false, lightnum, colormap);
+				HWR_AddTransparentWall(wallVerts, &Surf, gr_toptexture, PF_Environment, false, lightnum, colormap);
 			else
 				HWR_ProjectWall(wallVerts, &Surf, PF_Masked, lightnum, colormap);
 		}
@@ -1695,13 +1699,13 @@ static void HWR_StoreWallRange(double startfrac, double endfrac)
 #ifdef ESLOPE
 			worldlowslope > worldbottomslope ||
 #endif
-            worldlow > worldbottom) && texturetranslation[gr_sidedef->bottomtexture]) //only if VISIBLE!!!
+            worldlow > worldbottom) && gr_bottomtexture) //only if VISIBLE!!!
 		{
 			if (drawtextured)
 			{
 				fixed_t texturevpegbottom = 0; // bottom
 
-				grTex = HWR_GetTexture(texturetranslation[gr_sidedef->bottomtexture]);
+				grTex = HWR_GetTexture(gr_bottomtexture);
 
 				// PEGGING
 #ifdef ESLOPE
@@ -1721,7 +1725,7 @@ static void HWR_StoreWallRange(double startfrac, double endfrac)
 				texturevpegbottom += gr_sidedef->rowoffset;
 
 				// This is so that it doesn't overflow and screw up the wall, it doesn't need to go higher than the texture's height anyway
-				texturevpegbottom %= SHORT(textures[texturetranslation[gr_sidedef->bottomtexture]]->height)<<FRACBITS;
+				texturevpegbottom %= SHORT(textures[gr_bottomtexture]->height)<<FRACBITS;
 
 				wallVerts[3].t = wallVerts[2].t = texturevpegbottom * grTex->scaleY;
 				wallVerts[0].t = wallVerts[1].t = (texturevpegbottom + gr_backsector->floorheight - gr_frontsector->floorheight) * grTex->scaleY;
@@ -1766,13 +1770,13 @@ static void HWR_StoreWallRange(double startfrac, double endfrac)
 #endif
 
 			if (gr_frontsector->numlights)
-				HWR_SplitWall(gr_frontsector, wallVerts, texturetranslation[gr_sidedef->bottomtexture], &Surf, FF_CUTSOLIDS);
+				HWR_SplitWall(gr_frontsector, wallVerts, gr_bottomtexture, &Surf, FF_CUTSOLIDS);
 			else if (grTex->mipmap.flags & TF_TRANSPARENT)
-				HWR_AddTransparentWall(wallVerts, &Surf, texturetranslation[gr_sidedef->bottomtexture], PF_Environment, false, lightnum, colormap);
+				HWR_AddTransparentWall(wallVerts, &Surf, gr_bottomtexture, PF_Environment, false, lightnum, colormap);
 			else
 				HWR_ProjectWall(wallVerts, &Surf, PF_Masked, lightnum, colormap);
 		}
-		gr_midtexture = texturetranslation[gr_sidedef->midtexture];
+		gr_midtexture = R_GetTextureNum(gr_sidedef->midtexture);
 		if (gr_midtexture)
 		{
 			FBITFIELD blendmode;
@@ -2134,7 +2138,7 @@ static void HWR_StoreWallRange(double startfrac, double endfrac)
 	else
 	{
 		// Single sided line... Deal only with the middletexture (if one exists)
-		gr_midtexture = texturetranslation[gr_sidedef->midtexture];
+		gr_midtexture = R_GetTextureNum(gr_sidedef->midtexture);
 		if (gr_midtexture)
 		{
 			if (drawtextured)
@@ -2232,13 +2236,13 @@ static void HWR_StoreWallRange(double startfrac, double endfrac)
 				if (*rover->topheight < lowcut || *rover->bottomheight > highcut)
 					continue;
 
-				texnum = texturetranslation[sides[rover->master->sidenum[0]].midtexture];
+				texnum = R_GetTextureNum(sides[rover->master->sidenum[0]].midtexture);
 
 				if (rover->master->flags & ML_TFERLINE)
 				{
 					size_t linenum = gr_curline->linedef-gr_backsector->lines[0];
 					newline = rover->master->frontsector->lines[0] + linenum;
-					texnum = texturetranslation[sides[newline->sidenum[0]].midtexture];
+					texnum = R_GetTextureNum(sides[newline->sidenum[0]].midtexture);
 				}
 
 #ifdef ESLOPE
@@ -2366,13 +2370,13 @@ static void HWR_StoreWallRange(double startfrac, double endfrac)
 				if (*rover->topheight < lowcut || *rover->bottomheight > highcut)
 					continue;
 
-				texnum = texturetranslation[sides[rover->master->sidenum[0]].midtexture];
+				texnum = R_GetTextureNum(sides[rover->master->sidenum[0]].midtexture);
 
 				if (rover->master->flags & ML_TFERLINE)
 				{
 					size_t linenum = gr_curline->linedef-gr_backsector->lines[0];
 					newline = rover->master->frontsector->lines[0] + linenum;
-					texnum = texturetranslation[sides[newline->sidenum[0]].midtexture];
+					texnum = R_GetTextureNum(sides[newline->sidenum[0]].midtexture);
 				}
 #ifdef ESLOPE //backsides
 				h  = *rover->t_slope ? P_GetZAt(*rover->t_slope, v1x, v1y) : *rover->topheight;

src/p_maputl.c

@@ -572,51 +572,54 @@ void P_LineOpening(line_t *linedef, mobj_t *mobj)
 			side_t *side = &sides[linedef->sidenum[0]];
 			fixed_t textop, texbottom, texheight;
 			fixed_t texmid, delta1, delta2;
+			INT32 texnum = R_GetTextureNum(side->midtexture); // make sure the texture is actually valid
 
-			// Get the midtexture's height
+			if (texnum) {
-			texheight = textures[texturetranslation[side->midtexture]]->height << FRACBITS;
+				// Get the midtexture's height
+				texheight = textures[texnum]->height << FRACBITS;
 
-			// Set texbottom and textop to the Z coordinates of the texture's boundaries
+				// Set texbottom and textop to the Z coordinates of the texture's boundaries
 #if 0 // #ifdef POLYOBJECTS
-			// don't remove this code unless solid midtextures
+				// don't remove this code unless solid midtextures
-			// on non-solid polyobjects should NEVER happen in the future
+				// on non-solid polyobjects should NEVER happen in the future
-			if (linedef->polyobj && (linedef->polyobj->flags & POF_TESTHEIGHT)) {
+				if (linedef->polyobj && (linedef->polyobj->flags & POF_TESTHEIGHT)) {
-				if (linedef->flags & ML_EFFECT5 && !side->repeatcnt) { // "infinite" repeat
+					if (linedef->flags & ML_EFFECT5 && !side->repeatcnt) { // "infinite" repeat
-					texbottom = back->floorheight + side->rowoffset;
+						texbottom = back->floorheight + side->rowoffset;
-					textop = back->ceilingheight + side->rowoffset;
+						textop = back->ceilingheight + side->rowoffset;
-				} else if (!!(linedef->flags & ML_DONTPEGBOTTOM) ^ !!(linedef->flags & ML_EFFECT3)) {
+					} else if (!!(linedef->flags & ML_DONTPEGBOTTOM) ^ !!(linedef->flags & ML_EFFECT3)) {
-					texbottom = back->floorheight + side->rowoffset;
+						texbottom = back->floorheight + side->rowoffset;
-					textop = texbottom + texheight*(side->repeatcnt+1);
+						textop = texbottom + texheight*(side->repeatcnt+1);
-				} else {
+					} else {
-					textop = back->ceilingheight + side->rowoffset;
+						textop = back->ceilingheight + side->rowoffset;
-					texbottom = textop - texheight*(side->repeatcnt+1);
+						texbottom = textop - texheight*(side->repeatcnt+1);
-				}
+					}
-			} else
+				} else
 #endif
-			{
+				{
-				if (linedef->flags & ML_EFFECT5 && !side->repeatcnt) { // "infinite" repeat
+					if (linedef->flags & ML_EFFECT5 && !side->repeatcnt) { // "infinite" repeat
-					texbottom = openbottom + side->rowoffset;
+						texbottom = openbottom + side->rowoffset;
-					textop = opentop + side->rowoffset;
+						textop = opentop + side->rowoffset;
-				} else if (!!(linedef->flags & ML_DONTPEGBOTTOM) ^ !!(linedef->flags & ML_EFFECT3)) {
+					} else if (!!(linedef->flags & ML_DONTPEGBOTTOM) ^ !!(linedef->flags & ML_EFFECT3)) {
-					texbottom = openbottom + side->rowoffset;
+						texbottom = openbottom + side->rowoffset;
-					textop = texbottom + texheight*(side->repeatcnt+1);
+						textop = texbottom + texheight*(side->repeatcnt+1);
-				} else {
+					} else {
-					textop = opentop + side->rowoffset;
+						textop = opentop + side->rowoffset;
-					texbottom = textop - texheight*(side->repeatcnt+1);
+						texbottom = textop - texheight*(side->repeatcnt+1);
+					}
 				}
-			}
 
-			texmid = texbottom+(textop-texbottom)/2;
+				texmid = texbottom+(textop-texbottom)/2;
 
-			delta1 = abs(mobj->z - texmid);
+				delta1 = abs(mobj->z - texmid);
-			delta2 = abs(thingtop - texmid);
+				delta2 = abs(thingtop - texmid);
 
-			if (delta1 > delta2) { // Below
+				if (delta1 > delta2) { // Below
-				if (opentop > texbottom)
+					if (opentop > texbottom)
-					opentop = texbottom;
+						opentop = texbottom;
-			} else { // Above
+				} else { // Above
-				if (openbottom < textop)
+					if (openbottom < textop)
-					openbottom = textop;
+						openbottom = textop;
+				}
 			}
 		}
 

src/r_data.c

@@ -303,6 +303,32 @@ done:
 	return blocktex;
 }
 
+//
+// R_GetTextureNum
+//
+// Returns the actual texture id that we should use.
+// This can either be texnum, the current frame for texnum's anim (if animated),
+// or 0 if not valid.
+//
+INT32 R_GetTextureNum(INT32 texnum)
+{
+	if (texnum < 0 || texnum >= numtextures)
+		return 0;
+	return texturetranslation[texnum];
+}
+
+//
+// R_CheckTextureCache
+//
+// Use this if you need to make sure the texture is cached before R_GetColumn calls
+// e.g.: midtextures and FOF walls
+//
+void R_CheckTextureCache(INT32 tex)
+{
+	if (!texturecache[tex])
+		R_GenerateTexture(tex);
+}
+
 //
 // R_GetColumn
 //

src/r_data.h

@@ -65,6 +65,9 @@ extern CV_PossibleValue_t Color_cons_t[];
 void R_LoadTextures(void);
 void R_FlushTextureCache(void);
 
+INT32 R_GetTextureNum(INT32 texnum);
+void R_CheckTextureCache(INT32 tex);
+
 // Retrieve column data for span blitting.
 UINT8 *R_GetColumn(fixed_t tex, INT32 col);
 

src/r_defs.h

@@ -203,6 +203,7 @@ typedef struct r_lightlist_s
 	fixed_t heightstep;
 	fixed_t botheight;
 	fixed_t botheightstep;
+	fixed_t startheight; // for repeating midtextures
 	INT16 lightlevel;
 	extracolormap_t *extra_colormap;
 	lighttable_t *rcolormap;

src/r_segs.c

@@ -300,7 +300,7 @@ void R_RenderMaskedSegRange(drawseg_t *ds, INT32 x1, INT32 x2)
 	curline = ds->curline;
 	frontsector = curline->frontsector;
 	backsector = curline->backsector;
-	texnum = texturetranslation[curline->sidedef->midtexture];
+	texnum = R_GetTextureNum(curline->sidedef->midtexture);
 	windowbottom = windowtop = sprbotscreen = INT32_MAX;
 
 	// hack translucent linedef types (900-909 for transtables 1-9)
@@ -344,6 +344,9 @@ void R_RenderMaskedSegRange(drawseg_t *ds, INT32 x1, INT32 x2)
 	rw_scalestep = ds->scalestep;
 	spryscale = ds->scale1 + (x1 - ds->x1)*rw_scalestep;
 
+	// Texture must be cached before setting colfunc_2s,
+	// otherwise texture[texnum]->holes may be false when it shouldn't be
+	R_CheckTextureCache(texnum);
 	// handle case where multipatch texture is drawn on a 2sided wall, multi-patch textures
 	// are not stored per-column with post info in SRB2
 	if (textures[texnum]->holes)
@@ -391,6 +394,7 @@ void R_RenderMaskedSegRange(drawseg_t *ds, INT32 x1, INT32 x2)
 			rlight->height = (centeryfrac) - FixedMul((light->height - viewz), spryscale);
 			rlight->heightstep = -FixedMul(rw_scalestep, (light->height - viewz));
 #endif
+			rlight->startheight = rlight->height; // keep starting value here to reset for each repeat
 			rlight->lightlevel = *light->lightlevel;
 			rlight->extra_colormap = light->extra_colormap;
 			rlight->flags = light->flags;
@@ -484,6 +488,14 @@ void R_RenderMaskedSegRange(drawseg_t *ds, INT32 x1, INT32 x2)
 		{
 			rw_scalestep = ds->scalestep;
 			spryscale = ds->scale1 + (x1 - ds->x1)*rw_scalestep;
+			if (dc_numlights)
+			{ // reset all lights to their starting heights
+				for (i = 0; i < dc_numlights; i++)
+				{
+					rlight = &dc_lightlist[i];
+					rlight->height = rlight->startheight;
+				}
+			}
 		}
 
 #ifndef ESLOPE
@@ -740,7 +752,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 	curline = ds->curline;
 	backsector = pfloor->target;
 	frontsector = curline->frontsector == pfloor->target ? curline->backsector : curline->frontsector;
-	texnum = texturetranslation[sides[pfloor->master->sidenum[0]].midtexture];
+	texnum = R_GetTextureNum(sides[pfloor->master->sidenum[0]].midtexture);
 
 	colfunc = wallcolfunc;
 
@@ -748,7 +760,7 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 	{
 		size_t linenum = curline->linedef-backsector->lines[0];
 		newline = pfloor->master->frontsector->lines[0] + linenum;
-		texnum = texturetranslation[sides[newline->sidenum[0]].midtexture];
+		texnum = R_GetTextureNum(sides[newline->sidenum[0]].midtexture);
 	}
 
 	if (pfloor->flags & FF_TRANSLUCENT)
@@ -968,6 +980,9 @@ void R_RenderThickSideRange(drawseg_t *ds, INT32 x1, INT32 x2, ffloor_t *pfloor)
 
 	dc_texturemid += offsetvalue;
 
+	// Texture must be cached before setting colfunc_2s,
+	// otherwise texture[texnum]->holes may be false when it shouldn't be
+	R_CheckTextureCache(texnum);
 	//faB: handle case where multipatch texture is drawn on a 2sided wall, multi-patch textures
 	//     are not stored per-column with post info anymore in Doom Legacy
 	if (textures[texnum]->holes)
@@ -1878,14 +1893,16 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 
 	if (!backsector)
 	{
+		fixed_t texheight;
 		// single sided line
-		midtexture = texturetranslation[sidedef->midtexture];
+		midtexture = R_GetTextureNum(sidedef->midtexture);
+		texheight = textureheight[midtexture];
 		// a single sided line is terminal, so it must mark ends
 		markfloor = markceiling = true;
 #ifdef ESLOPE
 		if (linedef->flags & ML_EFFECT2) {
 			if (linedef->flags & ML_DONTPEGBOTTOM)
-				rw_midtexturemid = frontsector->floorheight + textureheight[sidedef->midtexture] - viewz;
+				rw_midtexturemid = frontsector->floorheight + texheight - viewz;
 			else
 				rw_midtexturemid = frontsector->ceilingheight - viewz;
 		}
@@ -1894,10 +1911,10 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 		if (linedef->flags & ML_DONTPEGBOTTOM)
 		{
 #ifdef ESLOPE
-			rw_midtexturemid = worldbottom + textureheight[sidedef->midtexture];
+			rw_midtexturemid = worldbottom + texheight;
 			rw_midtextureslide = floorfrontslide;
 #else
-			vtop = frontsector->floorheight + textureheight[sidedef->midtexture];
+			vtop = frontsector->floorheight + texheight;
 			// bottom of texture at bottom
 			rw_midtexturemid = vtop - viewz;
 #endif
@@ -2129,76 +2146,50 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 #endif
 			)
 		{
+			fixed_t texheight;
 			// top texture
 			if ((linedef->flags & (ML_DONTPEGTOP) && (linedef->flags & ML_DONTPEGBOTTOM))
 				&& linedef->sidenum[1] != 0xffff)
 			{
 				// Special case... use offsets from 2nd side but only if it has a texture.
 				side_t *def = &sides[linedef->sidenum[1]];
-				toptexture = texturetranslation[def->toptexture];
+				toptexture = R_GetTextureNum(def->toptexture);
 
 				if (!toptexture) //Second side has no texture, use the first side's instead.
-					toptexture = texturetranslation[sidedef->toptexture];
+					toptexture = R_GetTextureNum(sidedef->toptexture);
-
+				texheight = textureheight[toptexture];
-#ifdef ESLOPE
-				if (!(linedef->flags & ML_EFFECT1)) { // Ignore slopes for lower/upper textures unless flag is checked
-					if (linedef->flags & ML_DONTPEGTOP)
-						rw_toptexturemid = frontsector->ceilingheight - viewz;
-					else
-						rw_toptexturemid = backsector->ceilingheight - viewz;
-				} else
-#endif
-				if (linedef->flags & ML_DONTPEGTOP)
-				{
-					// top of texture at top
-					rw_toptexturemid = worldtop;
-#ifdef ESLOPE
-					rw_toptextureslide = ceilingfrontslide;
-#endif
-				}
-				else
-				{
-#ifdef ESLOPE
-					rw_toptexturemid = worldhigh + textureheight[def->toptexture];
-					rw_toptextureslide = ceilingbackslide;
-#else
-					vtop = backsector->ceilingheight + textureheight[def->toptexture];
-					// bottom of texture
-					rw_toptexturemid = vtop - viewz;
-#endif
-				}
 			}
 			else
 			{
-				toptexture = texturetranslation[sidedef->toptexture];
+				toptexture = R_GetTextureNum(sidedef->toptexture);
-
+				texheight = textureheight[toptexture];
+			}
 #ifdef ESLOPE
-				if (!(linedef->flags & ML_EFFECT1)) { // Ignore slopes for lower/upper textures unless flag is checked
+			if (!(linedef->flags & ML_EFFECT1)) { // Ignore slopes for lower/upper textures unless flag is checked
-					if (linedef->flags & ML_DONTPEGTOP)
-						rw_toptexturemid = frontsector->ceilingheight - viewz;
-					else
-						rw_toptexturemid = backsector->ceilingheight - viewz;
-				} else
-#endif
 				if (linedef->flags & ML_DONTPEGTOP)
-				{
+					rw_toptexturemid = frontsector->ceilingheight - viewz;
-					// top of texture at top
-					rw_toptexturemid = worldtop;
-#ifdef ESLOPE
-					rw_toptextureslide = ceilingfrontslide;
-#endif
-				}
 				else
-				{
+					rw_toptexturemid = backsector->ceilingheight - viewz;
-#ifdef ESLOPE
+			} else
-					rw_toptexturemid = worldhigh + textureheight[sidedef->toptexture];
+#endif
-					rw_toptextureslide = ceilingbackslide;
+			if (linedef->flags & ML_DONTPEGTOP)
-#else
+			{
-					vtop = backsector->ceilingheight + textureheight[sidedef->toptexture];
+				// top of texture at top
-					// bottom of texture
+				rw_toptexturemid = worldtop;
-					rw_toptexturemid = vtop - viewz;
+#ifdef ESLOPE
+				rw_toptextureslide = ceilingfrontslide;
+#endif
+			}
+			else
+			{
+#ifdef ESLOPE
+				rw_toptexturemid = worldhigh + texheight;
+				rw_toptextureslide = ceilingbackslide;
+#else
+				vtop = backsector->ceilingheight + texheight;
+				// bottom of texture
+				rw_toptexturemid = vtop - viewz;
 #endif
-				}
 			}
 		}
 		// check BOTTOM TEXTURE
@@ -2209,7 +2200,7 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 			)     //seulement si VISIBLE!!!
 		{
 			// bottom texture
-			bottomtexture = texturetranslation[sidedef->bottomtexture];
+			bottomtexture = R_GetTextureNum(sidedef->bottomtexture);
 
 #ifdef ESLOPE
 			if (!(linedef->flags & ML_EFFECT1)) { // Ignore slopes for lower/upper textures unless flag is checked
@@ -2494,7 +2485,7 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 
 			ds_p->numthicksides = numthicksides = i;
 		}
-		if (sidedef->midtexture)
+		if (sidedef->midtexture > 0 && sidedef->midtexture < numtextures)
 		{
 			// masked midtexture
 			if (!ds_p->thicksidecol)
@@ -3101,12 +3092,12 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 	if (maskedtexture && !(ds_p->silhouette & SIL_TOP))
 	{
 		ds_p->silhouette |= SIL_TOP;
-		ds_p->tsilheight = sidedef->midtexture ? INT32_MIN: INT32_MAX;
+		ds_p->tsilheight = (sidedef->midtexture > 0 && sidedef->midtexture < numtextures) ? INT32_MIN: INT32_MAX;
 	}
 	if (maskedtexture && !(ds_p->silhouette & SIL_BOTTOM))
 	{
 		ds_p->silhouette |= SIL_BOTTOM;
-		ds_p->bsilheight = sidedef->midtexture ? INT32_MAX: INT32_MIN;
+		ds_p->bsilheight = (sidedef->midtexture > 0 && sidedef->midtexture < numtextures) ? INT32_MAX: INT32_MIN;
 	}
 	ds_p++;
 }