- remove some obsolete code from decal rendering.

- avoid rebinding the same texture multiple times, as there's considerable overhead in the texture manager.
- check gl_sort_textures only once per scene, not per draw list.

src/gl/scene/gl_decal.cpp

@@ -349,11 +349,15 @@ void GLWall::DrawDecal(DBaseDecal *decal)
 //==========================================================================
 void GLWall::DoDrawDecals()
 {
-	DBaseDecal *decal = seg->sidedef->AttachedDecals;
-	while (decal)
+	if (seg->sidedef && seg->sidedef->AttachedDecals)
 	{
-		DrawDecal(decal);
-		decal = decal->WallNext;
+		gl_SetFog(lightlevel, rellight + getExtraLight(), &Colormap, false);
+		DBaseDecal *decal = seg->sidedef->AttachedDecals;
+		while (decal)
+		{
+			DrawDecal(decal);
+			decal = decal->WallNext;
+		}
 	}
 }
 

src/gl/scene/gl_drawinfo.cpp

@@ -59,8 +59,6 @@
 
 FDrawInfo * gl_drawinfo;
 
-CVAR(Bool, gl_sort_textures, true, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
-
 //==========================================================================
 //
 //
@@ -811,6 +809,19 @@ void GLDrawList::DrawFlats(int pass)
 	RenderFlat.Unclock();
 }
 
+//==========================================================================
+//
+//
+//
+//==========================================================================
+void GLDrawList::DrawDecals()
+{
+	for(unsigned i=0;i<drawitems.Size();i++)
+	{
+		walls[drawitems[i].index].DoDrawDecals();
+	}
+}
+
 //==========================================================================
 //
 // Sorting the drawitems first by texture and then by light level.
@@ -844,7 +855,7 @@ static int __cdecl difcmp (const void *a, const void *b)
 
 void GLDrawList::SortWalls()
 {
-	if (drawitems.Size()!=0 && gl_sort_textures)
+	if (drawitems.Size() > 1)
 	{
 		sortinfo=this;
 		qsort(&drawitems[0], drawitems.Size(), sizeof(drawitems[0]), diwcmp);
@@ -853,7 +864,7 @@ void GLDrawList::SortWalls()
 
 void GLDrawList::SortFlats()
 {
-	if (drawitems.Size()!=0 && gl_sort_textures)
+	if (drawitems.Size() > 1)
 	{
 		sortinfo=this;
 		qsort(&drawitems[0], drawitems.Size(), sizeof(drawitems[0]), difcmp);

src/gl/scene/gl_drawinfo.h

@@ -32,7 +32,6 @@ enum Drawpasses
 	GLPASS_LIGHTSONLY,	// only collect dynamic lights
 	GLPASS_PLAIN,		// Main pass without dynamic lights
 	GLPASS_DECALS,		// Draws a decal
-	GLPASS_DECALS_NOFOG,// Draws a decal without setting the fog (used for passes that need a fog layer)
 	GLPASS_TRANSLUCENT,	// Draws translucent objects
 };
 
@@ -130,6 +129,7 @@ public:
 	void Draw(int pass);
 	void DrawWalls(int pass);
 	void DrawFlats(int pass);
+	void DrawDecals();
 	
 	GLDrawList * next;
 } ;

src/gl/scene/gl_scene.cpp

@@ -85,6 +85,7 @@ CVAR(Bool, gl_texture, true, 0)
 CVAR(Bool, gl_no_skyclear, false, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 CVAR(Float, gl_mask_threshold, 0.5f,CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 CVAR(Float, gl_mask_sprite_threshold, 0.5f,CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
+CVAR(Bool, gl_sort_textures, false, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 
 EXTERN_CVAR (Int, screenblocks)
 EXTERN_CVAR (Bool, cl_capfps)
@@ -340,11 +341,14 @@ void FGLRenderer::RenderScene(int recursion)
 	gl_RenderState.EnableFog(true);
 	gl_RenderState.BlendFunc(GL_ONE,GL_ZERO);
 
-	gl_drawinfo->drawlists[GLDL_PLAINWALLS].SortWalls();
-	gl_drawinfo->drawlists[GLDL_PLAINFLATS].SortFlats();
-	gl_drawinfo->drawlists[GLDL_MASKEDWALLS].SortWalls();
-	gl_drawinfo->drawlists[GLDL_MASKEDFLATS].SortFlats();
-	gl_drawinfo->drawlists[GLDL_MASKEDWALLSOFS].SortWalls();
+	if (gl_sort_textures)
+	{
+		gl_drawinfo->drawlists[GLDL_PLAINWALLS].SortWalls();
+		gl_drawinfo->drawlists[GLDL_PLAINFLATS].SortFlats();
+		gl_drawinfo->drawlists[GLDL_MASKEDWALLS].SortWalls();
+		gl_drawinfo->drawlists[GLDL_MASKEDFLATS].SortFlats();
+		gl_drawinfo->drawlists[GLDL_MASKEDWALLSOFS].SortWalls();
+	}
 
 	// if we don't have a persistently mapped buffer, we have to process all the dynamic lights up front,
 	// so that we don't have to do repeated map/unmap calls on the buffer.
@@ -414,7 +418,7 @@ void FGLRenderer::RenderScene(int recursion)
 	glDepthMask(false);
 
 	// this is the only geometry type on which decals can possibly appear
-	gl_drawinfo->drawlists[GLDL_PLAINWALLS].Draw(GLPASS_DECALS);
+	gl_drawinfo->drawlists[GLDL_PLAINWALLS].DrawDecals();
 
 	gl_RenderState.SetTextureMode(TM_MODULATE);
 

src/gl/scene/gl_walls_draw.cpp

@@ -395,18 +395,6 @@ void GLWall::Draw(int pass)
 		gl_RenderState.EnableGlow(false);
 		break;
 
-	case GLPASS_DECALS:
-	case GLPASS_DECALS_NOFOG:
-		if (seg->sidedef && seg->sidedef->AttachedDecals)
-		{
-			if (pass==GLPASS_DECALS) 
-			{
-				gl_SetFog(lightlevel, rellight + getExtraLight(), &Colormap, false);
-			}
-			DoDrawDecals();
-		}
-		break;
-
 	case GLPASS_TRANSLUCENT:
 		switch (type)
 		{

src/gl/textures/gl_material.cpp

@@ -611,15 +611,27 @@ outl:
 //
 //===========================================================================
 
+static FMaterial *last;
+static int lastclamp;
+static int lasttrans;
+static bool lastalpha;
+
 void FMaterial::Bind(int clampmode, int translation, int overrideshader, bool alphatexture)
 {
-	int usebright = false;
 	int shaderindex = overrideshader >= 0? overrideshader : mShaderIndex;
+	gl_RenderState.SetShader(shaderindex, tex->gl_info.shaderspeed);
+
+	// avoid rebinding the same texture multiple times.
+	if (this == last && lastclamp == clampmode && translation == lasttrans && lastalpha == alphatexture) return;
+	last = this;
+	lastclamp = clampmode;
+	lastalpha = alphatexture;
+	lasttrans = translation;
+
+	int usebright = false;
 	int maxbound = 0;
 	bool allowhires = tex->xScale == FRACUNIT && tex->yScale == FRACUNIT && clampmode <= CLAMP_XY && !mExpanded;
 
-	gl_RenderState.SetShader(shaderindex, tex->gl_info.shaderspeed);
-
 	if (tex->bHasCanvas) clampmode = CLAMP_CAMTEX;
 	else if (tex->bWarped && clampmode <= CLAMP_XY) clampmode = CLAMP_NONE;
 

wadsrc/static/menudef.z

@@ -139,6 +139,7 @@ OptionMenu "GLTextureGLOptions"
 	Option "Precache GL textures",		gl_precache,					"YesNo"
 	Option "Camera textures offscreen",	gl_usefb,						"OnOff"
 	Option "Trim sprite edges",			gl_trimsprites,					"OnOff"
+	Option "Sort draw lists by texture", gl_sort_textures,				"YesNo"
 }
 
 OptionMenu "GLLightOptions"