renderer: disable FXAA when MSAA is enabled (prefer MSAA)

Author: illwieckz

src/engine/renderer/GLUtils.h

@@ -156,6 +156,7 @@ struct GLConfig
 	bool reflectionMappingAvailable;
 	bool reflectionMapping;
 	bool bloom;
+	bool FXAA; // automatically disabled when MSAA is not null
 	int  MSAA; // 0 == disabled, otherwise used as sample count
 	bool ssao;
 	bool motionBlur;

src/engine/renderer/gl_shader.cpp

@@ -802,7 +802,7 @@ static std::string GenEngineConstants() {
 		AddDefine( str, "r_showLuma", 1 );
 	}
 
-	if ( r_FXAA.Get() )
+	if ( glConfig.FXAA )
 	{
 		AddDefine( str, "r_FXAA", 1 );
 

src/engine/renderer/tr_backend.cpp

@@ -1603,7 +1603,7 @@ void RB_RenderSSAO()
 
 void RB_FXAA()
 {
-	if ( !r_FXAA.Get() || !gl_fxaaShader || !glConfig.samplerObjectsAvailable )
+	if ( !glConfig.FXAA || !gl_fxaaShader )
 	{
 		return;
 	}
@@ -1736,7 +1736,7 @@ void RB_CameraPostFX() {
 		GL_BindToTMU( 0, tr.currentRenderImage[backEnd.currentMainFBO] ) 
 	);
 
-	if ( r_FXAA.Get() && gl_fxaaShader && glConfig.samplerObjectsAvailable )
+	if ( r_FXAA.Get() && gl_fxaaShader )
 	{
 		// Swap main FBOs.
 		backEnd.currentMainFBO = 1 - backEnd.currentMainFBO;

src/engine/renderer/tr_shade.cpp

@@ -192,6 +192,20 @@ static void EnableAvailableFeatures()
 		Log::Warn( "MSAA unavailable because GL version is lower than required (%i.%i < %i.%i)", glConfig.glMajor, glConfig.glMinor, 3, 2 );
 	}
 
+	glConfig.FXAA = r_FXAA.Get();
+
+	if ( glConfig.FXAA && glConfig.MSAA )
+	{
+		Log::Notice( "FXAA disabled because MSAA is enabled." );
+		glConfig.FXAA = false;
+	}
+
+	if ( glConfig.FXAA && !glConfig.samplerObjectsAvailable )
+	{
+		Log::Warn( "FXAA disabled because ARB_sampler_objects is not available." );
+		glConfig.FXAA = false;
+	}
+
 	glConfig.usingMaterialSystem = r_materialSystem.Get() && glConfig.materialSystemAvailable;
 	glConfig.usingBindlessTextures = glConfig.usingMaterialSystem ||
 		( r_preferBindlessTextures.Get() && glConfig.bindlessTexturesAvailable );
@@ -369,7 +383,7 @@ static void GLSL_InitGPUShadersOrError()
 		gl_ssaoShader->MarkProgramForBuilding();
 	}
 
-	if ( r_FXAA.Get() )
+	if ( glConfig.FXAA )
 	{
 		gl_shaderManager.LoadShader( gl_fxaaShader );