WIP: naive blending compatibility

Author: illwieckz

src/engine/renderer/tr_init.cpp

@@ -1283,7 +1283,7 @@ ScreenshotCmd screenshotPNGRegistration("screenshotPNG", ssFormat_t::SSF_PNG, "p
 	}
 
 	static float convertFloatFromSRGB_NOP( float f ) { return f; }
-	static Color::Color convertColorFromSRGB_NOP( Color::Color c ) { return c; }
+	Color::Color convertColorFromSRGB_NOP( Color::Color c ) { return c; }
 
 	/*
 	===============

src/engine/renderer/tr_local.h

@@ -979,6 +979,11 @@ enum
 		ALL = BIT( 3 )
 	};
 
+	using floatProcessor_t = float(*)(float);
+	using colorProcessor_t = Color::Color(*)(Color::Color);
+
+	Color::Color convertColorFromSRGB_NOP( Color::Color c );
+
 	struct shaderStage_t
 	{
 		stageType_t     type;
@@ -1004,6 +1009,7 @@ enum
 		stageType_t collapsedStageTypes[ MAX_TEXTURE_BUNDLES ];
 		char collapsedStageTextures[ MAX_TEXTURE_BUNDLES ][ MAX_QPATH ];
 
+		colorProcessor_t convertColorFromSRGB;
 		expression_t    ifExp;
 
 		waveForm_t      rgbWave;
@@ -2401,9 +2407,6 @@ enum
 		int       h;
 	};
 
-	using floatProcessor_t = float(*)(float);
-	using colorProcessor_t = Color::Color(*)(Color::Color);
-
 	/*
 	** trGlobals_t
 	**

src/engine/renderer/tr_shade.cpp

@@ -1698,7 +1698,7 @@ void Tess_ComputeColor( shaderStage_t *pStage )
 			{
 				tess.svars.color = pStage->constantColor;
 				tess.svars.color.Clamp();
-				tess.svars.color = tr.convertColorFromSRGB( tess.svars.color );
+				tess.svars.color = pStage->convertColorFromSRGB( tess.svars.color );
 				break;
 			}
 
@@ -1708,7 +1708,7 @@ void Tess_ComputeColor( shaderStage_t *pStage )
 				{
 					tess.svars.color = backEnd.currentEntity->e.shaderRGBA;
 					tess.svars.color.Clamp();
-					tess.svars.color = tr.convertColorFromSRGB( tess.svars.color );
+					tess.svars.color = pStage->convertColorFromSRGB( tess.svars.color );
 				}
 				else
 				{
@@ -1724,7 +1724,7 @@ void Tess_ComputeColor( shaderStage_t *pStage )
 				{
 					tess.svars.color = backEnd.currentEntity->e.shaderRGBA;
 					tess.svars.color.Clamp();
-					tess.svars.color = tr.convertColorFromSRGB( tess.svars.color );
+					tess.svars.color = pStage->convertColorFromSRGB( tess.svars.color );
 				}
 				else
 				{
@@ -1757,7 +1757,7 @@ void Tess_ComputeColor( shaderStage_t *pStage )
 
 				tess.svars.color = Color::White * glow;
 				tess.svars.color.Clamp();
-				tess.svars.color = tr.convertColorFromSRGB( tess.svars.color );
+				tess.svars.color = pStage->convertColorFromSRGB( tess.svars.color );
 				break;
 			}
 

src/engine/renderer/tr_shader.cpp

@@ -1480,6 +1480,20 @@ static bool LoadMap( shaderStage_t *stage, const char *buffer, stageType_t type,
 			{
 				case stageType_t::ST_COLORMAP:
 				case stageType_t::ST_DIFFUSEMAP:
+					{
+						int blendSrcBits = stage->stateBits & GLS_SRCBLEND_BITS;
+						int blendDstBits = stage->stateBits & GLS_DSTBLEND_BITS;
+
+						bool blended = blendSrcBits != 0 && blendDstBits != 0
+							&& !(blendSrcBits == GLS_SRCBLEND_ONE && blendDstBits == GLS_DSTBLEND_ZERO);
+
+						if ( !blended )
+						{
+							imageParams.bits |= IF_SRGB;
+							stage->convertColorFromSRGB = tr.convertColorFromSRGB;
+						}
+					}
+					break;
 				case stageType_t::ST_GLOWMAP:
 				case stageType_t::ST_REFLECTIONMAP:
 				case stageType_t::ST_SKYBOXMAP:
@@ -2072,6 +2086,8 @@ static bool ParseStage( shaderStage_t *stage, const char **text )
 	char         buffer[ 1024 ] = "";
 	bool     loadMap = false;
 
+	stage->convertColorFromSRGB = convertColorFromSRGB_NOP;
+
 	while ( true )
 	{
 		token = COM_ParseExt2( text, true );