Added material textures/common/occlusion

base/materials/invisible.mtr

@@ -433,4 +433,13 @@ textures/common/origin
 	qer_nocarve		// don't let an awry CSG operation cut it up
 	origin
 }
+
+// if an ASE/LWO/GLTF model has a surface that uses this material that surface will
+// be used for occlusion culling instead of the visual surface(s)
+textures/common/occlusion
+{
+	qer_editorimage textures/common/occlusion.tga
+	noshadows
+	occlusion
+}
 // RB end

neo/renderer/Material.cpp

@@ -341,6 +341,7 @@ static infoParm_t	infoParms[] =
 	// because they represent discrete objects like gui shaders
 	// mirrors, or autosprites
 	{"noFragment",	0,	SURF_NOFRAGMENT,	0 },
+	{"occlusion",	0,	SURF_OCCLUSION,	0 },		// RB: surface becomes vis blocker in software depth buffer
 
 	{"slick",		0,	SURF_SLICK,		0 },
 	{"collision",	0,	SURF_COLLISION,	0 },

neo/renderer/Material.h

@@ -441,8 +441,8 @@ typedef enum
 	SURF_NOSTEPS				= BIT( 9 ),	// no footstep sounds
 	SURF_DISCRETE				= BIT( 10 ),	// not clipped or merged by utilities
 	SURF_NOFRAGMENT				= BIT( 11 ),	// dmap won't cut surface at each bsp boundary
-	SURF_NULLNORMAL				= BIT( 12 )	// renderbump will draw this surface as 0x80 0x80 0x80, which
-								  // won't collect light from any angle
+	SURF_NULLNORMAL				= BIT( 12 ),	// renderbump will draw this surface as 0x80 0x80 0x80, which won't collect light from any angle
+	SURF_OCCLUSION				= BIT( 13 ),	// RB: occluder surface
 } surfaceFlags_t;
 
 
@@ -684,6 +684,12 @@ public:
 		return ( surfaceFlags & SURF_NOFRAGMENT ) != 0;
 	}
 
+	// RB: occluder surfaces are invisible and only get rendered to the masked occlusion depth buffer
+	bool				IsOccluder() const
+	{
+		return ( surfaceFlags & SURF_OCCLUSION ) != 0;
+	}
+
 	//------------------------------------------------------------------
 	// light shader specific functions, only called for light entities
 

neo/renderer/tr_frontend_masked_occlusion_culling.cpp

@@ -196,6 +196,23 @@ void R_RenderSingleModel( viewEntity_t* vEntity )
 	//---------------------------
 	// add all the model surfaces
 	//---------------------------
+	bool occlusionSurface = false;
+	for( int surfaceNum = 0; surfaceNum < model->NumSurfaces(); surfaceNum++ )
+	{
+		const modelSurface_t* surf = model->Surface( surfaceNum );
+
+		const idMaterial* shader = surf->shader;
+		if( shader == NULL )
+		{
+			continue;
+		}
+
+		if( shader->IsOccluder() )
+		{
+			occlusionSurface = true;
+		}
+	}
+
 	for( int surfaceNum = 0; surfaceNum < model->NumSurfaces(); surfaceNum++ )
 	{
 		const modelSurface_t* surf = model->Surface( surfaceNum );
@@ -221,6 +238,12 @@ void R_RenderSingleModel( viewEntity_t* vEntity )
 			continue;
 		}
 
+		// if the model has a occlusion surface and this surface is not a occluder
+		if( occlusionSurface && !shader->IsOccluder() )
+		{
+			continue;
+		}
+
 		// motorsep 11-24-2014; checking for LOD surface for LOD1 iteration
 		if( shader->IsLOD() )
 		{
@@ -249,7 +272,7 @@ void R_RenderSingleModel( viewEntity_t* vEntity )
 		}
 
 		// foresthale 2014-09-01: don't skip surfaces that use the "forceShadows" flag
-		if( !shader->IsDrawn() && !shader->SurfaceCastsShadow() )
+		if( !shader->IsDrawn() && !shader->SurfaceCastsShadow() && !shader->IsOccluder() )
 		{
 			continue;		// collision hulls, etc
 		}
@@ -330,13 +353,16 @@ void R_RenderSingleModel( viewEntity_t* vEntity )
 		const float* shaderRegisters = NULL;
 		drawSurf_t* baseDrawSurf = NULL;
 
-		if( surfaceDirectlyVisible && shader->IsDrawn() && shader->Coverage() == MC_OPAQUE && !renderEntity->weaponDepthHack && renderEntity->modelDepthHack == 0.0f )
-			//if( surfaceDirectlyVisible && shader->IsDrawn() && !renderEntity->weaponDepthHack && renderEntity->modelDepthHack == 0.0f )
+		if( surfaceDirectlyVisible &&
+				( ( shader->IsDrawn() && shader->Coverage() == MC_OPAQUE && !renderEntity->weaponDepthHack && renderEntity->modelDepthHack == 0.0f ) || shader->IsOccluder() )
+		  )
 		{
 			// render to masked occlusion buffer
 
 			//if( !gpuSkinned )
-			if( model->IsStaticWorldModel() )
+
+			// render the BSP area surfaces and from static model entities only the occlusion surfaces to keep the tris count at minimum
+			if( model->IsStaticWorldModel() || ( shader->IsOccluder() && !gpuSkinned ) )
 			{
 				tr.pc.c_mocIndexes += tri->numIndexes;
 				tr.pc.c_mocVerts += tri->numIndexes;