Respect GL_MAX_UNIFORM_BLOCK_SIZE for dlights buffer

Author: slipher

src/engine/renderer/GLUtils.h

@@ -147,6 +147,7 @@ struct GLConfig
 
 	bool colorGrading;
 	bool realtimeLighting;
+	int maxRealtimeLights;
 	int realtimeLightLayers;
 	bool deluxeMapping;
 	bool normalMapping;

src/engine/renderer/gl_shader.cpp

@@ -678,7 +678,7 @@ static std::string GenEngineConstants() {
 	AddDefine( str, "r_zNear", r_znear->value );
 
 	AddDefine( str, "M_PI", static_cast< float >( M_PI ) );
-	AddDefine( str, "MAX_REF_LIGHTS", MAX_REF_LIGHTS );
+	AddDefine( str, "MAX_REALTIME_LIGHTS", glConfig.maxRealtimeLights );
 	AddDefine( str, "NUM_LIGHT_LAYERS", glConfig.realtimeLightLayers );
 	AddDefine( str, "TILE_SIZE", TILE_SIZE );
 

src/engine/renderer/glsl_source/computeLight_fp.glsl

@@ -164,7 +164,7 @@ layout(std140, binding = BIND_LIGHTS) uniform u_Lights {
 #else
 layout(std140) uniform u_Lights {
 #endif
-	Light lights[MAX_REF_LIGHTS];
+	Light lights[MAX_REALTIME_LIGHTS];
 };
 
 #define GetLight( idx ) lights[idx]

src/engine/renderer/glsl_source/lighttile_fp.glsl

@@ -52,7 +52,7 @@ layout(std140, binding = BIND_LIGHTS) uniform u_Lights {
 #else
 layout(std140) uniform u_Lights {
 #endif
-	Light lights[MAX_REF_LIGHTS];
+	Light lights[MAX_REALTIME_LIGHTS];
 };
 
 Light GetLight( in uint idx ) {

src/engine/renderer/tr_scene.cpp

@@ -336,7 +336,7 @@ void RE_AddDynamicLightToScene( const vec3_t org, float radius, float r, float g
 		return;
 	}
 
-	if ( r_numLights >= MAX_REF_LIGHTS )
+	if ( r_numLights >= glConfig.maxRealtimeLights )
 	{
 		return;
 	}

src/engine/renderer/tr_shade.cpp

@@ -73,15 +73,19 @@ static void EnableAvailableFeatures()
 	}
 
 	if ( glConfig.realtimeLighting ) {
+		// Minimum possible is 16384 / 48 = 341
+		glConfig.maxRealtimeLights =
+			std::min<size_t>( MAX_REF_LIGHTS, glConfig.maxUniformBlockSize / sizeof( shaderLight_t ) );
+
 		glConfig.realtimeLightLayers = r_realtimeLightLayers.Get();
 
 		if ( glConfig.realtimeLightLayers > glConfig.max3DTextureSize ) {
 			glConfig.realtimeLightLayers = glConfig.max3DTextureSize;
 			Log::Notice( "r_realtimeLightLayers exceeds maximum 3D texture size, using %i instead.", glConfig.max3DTextureSize );
 		}
 
-		Log::Notice( "Using %i dynamic light layers, %i dynamic lights available per tile", glConfig.realtimeLightLayers,
-			glConfig.realtimeLightLayers * 16 );
+		Log::Notice( "Using %i dynamic light layers, %i dynamic lights available per tile, max %d lights",
+			glConfig.realtimeLightLayers, glConfig.realtimeLightLayers * 16, glConfig.maxRealtimeLights );
 	}
 
 	glConfig.colorGrading = r_colorGrading.Get();

src/engine/renderer/tr_vbo.cpp

@@ -698,7 +698,7 @@ static void R_InitLightUBO()
 	if( glConfig.uniformBufferObjectAvailable ) {
 		glGenBuffers( 1, &tr.dlightUBO );
 		glBindBuffer( GL_UNIFORM_BUFFER, tr.dlightUBO );
-		glBufferData( GL_UNIFORM_BUFFER, MAX_REF_LIGHTS * sizeof( shaderLight_t ), nullptr, GL_DYNAMIC_DRAW );
+		glBufferData( GL_UNIFORM_BUFFER, glConfig.maxRealtimeLights * sizeof( shaderLight_t ), nullptr, GL_DYNAMIC_DRAW );
 		glBindBuffer( GL_UNIFORM_BUFFER, 0 );
 	}
 }