Implement the rest of PushBuffer

- Generalise uniform post-processing
- Add `GLShader.pushSkip` and `GLShader._pushUniforms`. Add `padding` back to the `GLShader` size calculations in material system.
- Add GlobalUBOProxy, required for `PushBuffer` to set global uniform values outside of their shaders.
- Add `PostProcessGlobalUniforms()`: set `GLShaderManager.globalUniformBlock` to the struct + defines text, which will be the same for all shaders.
- GLUniform._global -> _updateType: required for `PushBuffer` to correctly sort uniforms. Also updates `GLShader.WriteUniformsToBuffer()` to use `mode` and `filter` arguments to select the correct uniforms.
- Add global UBO in PushBuffer
- Post-process shaders to actually add the `globalUniformBlock`, add `SetConstUniforms()` and `SetFrameUniforms()` functions to the core and material system renderers, and add the supporting glsl code.
- Fix quake3 fog with material system

Author: VReaperV

src/engine/renderer/GLMemory.cpp

@@ -117,6 +117,10 @@ void GLStagingBuffer::FlushAll() {
 	FlushStagingCopyQueue();
 }
 
+bool GLStagingBuffer::Active() const {
+	return buffer.id;
+}
+
 void GLStagingBuffer::InitGLBuffer() {
 	buffer.GenBuffer();
 
@@ -136,6 +140,10 @@ void GLStagingBuffer::FreeGLBuffer() {
 
 void PushBuffer::InitGLBuffers() {
 	globalUBO.GenBuffer();
+
+	globalUBO.BufferStorage( pushBuffer.constUniformsSize + pushBuffer.frameUniformsSize, 1, nullptr );
+
+	globalUBO.BindBufferBase();
 }
 
 void PushBuffer::FreeGLBuffers() {

src/engine/renderer/GLMemory.h

@@ -175,6 +175,7 @@ class GLBuffer {
 
 	void DelBuffer() {
 		glDeleteBuffers( 1, &id );
+		id = 0;
 		mapped = false;
 	}
 
@@ -303,6 +304,8 @@ class GLStagingBuffer {
 	void FlushStagingCopyQueue();
 	void FlushAll();
 
+	bool Active() const;
+
 	void InitGLBuffer();
 	void FreeGLBuffer();
 

src/engine/renderer/GLUtils.h

@@ -123,6 +123,7 @@ struct GLConfig
 	bool usingMaterialSystem; // are we using it right now
 	bool geometryCacheAvailable;
 	bool usingGeometryCache;
+	bool pushBufferAvailable;
 	bool gpuShader4Available;
 	bool gpuShader5Available;
 	bool textureGatherAvailable;

src/engine/renderer/Material.cpp

@@ -161,7 +161,7 @@ void UpdateSurfaceDataGeneric3D( uint32_t* materials, shaderStage_t* pStage, boo
 
 	gl_genericShaderMaterial->SetUniform_DepthScale( pStage->depthFadeValue );
 
-	gl_genericShaderMaterial->WriteUniformsToBuffer( materials );
+	gl_genericShaderMaterial->WriteUniformsToBuffer( materials, GLShader::MATERIAL );
 }
 
 void UpdateSurfaceDataLightMapping( uint32_t* materials, shaderStage_t* pStage, bool, bool vertexLit, bool fullbright ) {
@@ -207,7 +207,7 @@ void UpdateSurfaceDataLightMapping( uint32_t* materials, shaderStage_t* pStage,
 
 	gl_lightMappingShaderMaterial->SetUniform_SpecularExponent( specExpMin, specExpMax );
 
-	gl_lightMappingShaderMaterial->WriteUniformsToBuffer( materials );
+	gl_lightMappingShaderMaterial->WriteUniformsToBuffer( materials, GLShader::MATERIAL );
 }
 
 void UpdateSurfaceDataReflection( uint32_t* materials, shaderStage_t* pStage, bool, bool, bool ) {
@@ -244,7 +244,7 @@ void UpdateSurfaceDataReflection( uint32_t* materials, shaderStage_t* pStage, bo
 	gl_reflectionShaderMaterial->SetUniform_ReliefDepthScale( depthScale );
 	gl_reflectionShaderMaterial->SetUniform_ReliefOffsetBias( shader->reliefOffsetBias );
 
-	gl_reflectionShaderMaterial->WriteUniformsToBuffer( materials );
+	gl_reflectionShaderMaterial->WriteUniformsToBuffer( materials, GLShader::MATERIAL );
 }
 
 void UpdateSurfaceDataSkybox( uint32_t* materials, shaderStage_t* pStage, bool, bool, bool ) {
@@ -255,7 +255,7 @@ void UpdateSurfaceDataSkybox( uint32_t* materials, shaderStage_t* pStage, bool,
 	// u_AlphaThreshold
 	gl_skyboxShaderMaterial->SetUniform_AlphaTest( GLS_ATEST_NONE );
 
-	gl_skyboxShaderMaterial->WriteUniformsToBuffer( materials );
+	gl_skyboxShaderMaterial->WriteUniformsToBuffer( materials, GLShader::MATERIAL );
 }
 
 void UpdateSurfaceDataScreen( uint32_t* materials, shaderStage_t* pStage, bool, bool, bool ) {
@@ -268,7 +268,7 @@ void UpdateSurfaceDataScreen( uint32_t* materials, shaderStage_t* pStage, bool,
 	this seems to be the only material system shader that might need it to not be global */
 	gl_screenShaderMaterial->SetUniform_CurrentMapBindless( BindAnimatedImage( 0, &pStage->bundle[TB_COLORMAP] ) );
 
-	gl_screenShaderMaterial->WriteUniformsToBuffer( materials );
+	gl_screenShaderMaterial->WriteUniformsToBuffer( materials, GLShader::MATERIAL );
 }
 
 void UpdateSurfaceDataHeatHaze( uint32_t* materials, shaderStage_t* pStage, bool, bool, bool ) {
@@ -285,7 +285,7 @@ void UpdateSurfaceDataHeatHaze( uint32_t* materials, shaderStage_t* pStage, bool
 	// bind u_NormalScale
 	gl_heatHazeShaderMaterial->SetUniform_NormalScale( normalScale );
 
-	gl_heatHazeShaderMaterial->WriteUniformsToBuffer( materials );
+	gl_heatHazeShaderMaterial->WriteUniformsToBuffer( materials, GLShader::MATERIAL );
 }
 
 void UpdateSurfaceDataLiquid( uint32_t* materials, shaderStage_t* pStage, bool, bool, bool ) {
@@ -331,15 +331,15 @@ void UpdateSurfaceDataLiquid( uint32_t* materials, shaderStage_t* pStage, bool,
 
 	gl_liquidShaderMaterial->SetUniform_NormalScale( normalScale );
 
-	gl_liquidShaderMaterial->WriteUniformsToBuffer( materials );
+	gl_liquidShaderMaterial->WriteUniformsToBuffer( materials, GLShader::MATERIAL );
 }
 
 void UpdateSurfaceDataFog( uint32_t* materials, shaderStage_t* pStage, bool, bool, bool ) {
 	// shader_t* shader = pStage->shader;
 
 	materials += pStage->bufferOffset;
 
-	gl_fogQuake3ShaderMaterial->WriteUniformsToBuffer( materials );
+	gl_fogQuake3ShaderMaterial->WriteUniformsToBuffer( materials, GLShader::MATERIAL );
 }
 
 /*
@@ -1621,9 +1621,24 @@ void MaterialSystem::UpdateDynamicSurfaces() {
 	GL_CheckErrors();
 }
 
+void MaterialSystem::SetConstUniforms() {
+	globalUBOProxy->SetUniform_SurfaceDescriptorsCount( surfaceDescriptorsCount );
+	uint32_t globalWorkGroupX = surfaceDescriptorsCount % MAX_COMMAND_COUNTERS == 0 ?
+		surfaceDescriptorsCount / MAX_COMMAND_COUNTERS : surfaceDescriptorsCount / MAX_COMMAND_COUNTERS + 1;
+
+	globalUBOProxy->SetUniform_FirstPortalGroup( globalWorkGroupX );
+	globalUBOProxy->SetUniform_TotalPortals( totalPortals );
+}
+
+void MaterialSystem::SetFrameUniforms() {
+	globalUBOProxy->SetUniform_Frame( nextFrame );
+
+	globalUBOProxy->SetUniform_UseFrustumCulling( r_gpuFrustumCulling.Get() );
+	globalUBOProxy->SetUniform_UseOcclusionCulling( r_gpuOcclusionCulling.Get() );
+}
+
 void MaterialSystem::UpdateFrameData() {
 	gl_clearSurfacesShader->BindProgram();
-	gl_clearSurfacesShader->SetUniform_Frame( nextFrame );
 	gl_clearSurfacesShader->DispatchCompute( MAX_VIEWS, 1, 1 );
 
 	GL_CheckErrors();
@@ -1709,15 +1724,9 @@ void MaterialSystem::CullSurfaces() {
 		uint32_t globalWorkGroupX = surfaceDescriptorsCount % MAX_COMMAND_COUNTERS == 0 ?
 			surfaceDescriptorsCount / MAX_COMMAND_COUNTERS : surfaceDescriptorsCount / MAX_COMMAND_COUNTERS + 1;
 		GL_Bind( depthImage );
-		gl_cullShader->SetUniform_Frame( nextFrame );
 		gl_cullShader->SetUniform_ViewID( view );
-		gl_cullShader->SetUniform_SurfaceDescriptorsCount( surfaceDescriptorsCount );
-		gl_cullShader->SetUniform_UseFrustumCulling( r_gpuFrustumCulling.Get() );
-		gl_cullShader->SetUniform_UseOcclusionCulling( r_gpuOcclusionCulling.Get() );
 		gl_cullShader->SetUniform_CameraPosition( origin );
 		gl_cullShader->SetUniform_ModelViewMatrix( viewMatrix );
-		gl_cullShader->SetUniform_FirstPortalGroup( globalWorkGroupX );
-		gl_cullShader->SetUniform_TotalPortals( totalPortals );
 		gl_cullShader->SetUniform_ViewWidth( depthImage->width );
 		gl_cullShader->SetUniform_ViewHeight( depthImage->height );
 		gl_cullShader->SetUniform_SurfaceCommandsOffset( surfaceCommandsCount * ( MAX_VIEWS * nextFrame + view ) );
@@ -1749,7 +1758,6 @@ void MaterialSystem::CullSurfaces() {
 		gl_cullShader->DispatchCompute( globalWorkGroupX, 1, 1 );
 
 		gl_processSurfacesShader->BindProgram();
-		gl_processSurfacesShader->SetUniform_Frame( nextFrame );
 		gl_processSurfacesShader->SetUniform_ViewID( view );
 		gl_processSurfacesShader->SetUniform_SurfaceCommandsOffset( surfaceCommandsCount * ( MAX_VIEWS * nextFrame + view ) );
 

src/engine/renderer/Material.h

@@ -362,6 +362,8 @@ class MaterialSystem {
 
 	void StartFrame();
 	void EndFrame();
+	void SetConstUniforms();
+	void SetFrameUniforms();
 
 	void GenerateDepthImages( const int width, const int height, imageParams_t imageParms );