Don't recalculate deform index for every shader stage

Author: slipher

src/engine/renderer/tr_local.h

@@ -1145,7 +1145,7 @@ enum class realtimeLightingRenderer_t { LEGACY, TILED };
 
 		bool            isCubeMap;
 
-		int             deformIndex;
+		int deformIndex; // FIXME: should be on the shader level, not per-stage
 		bool        overrideNoPicMip; // for images that must always be full resolution
 		bool        overrideFilterType; // for console fonts, 2D elements, etc.
 		filterType_t    filterType;

src/engine/renderer/tr_shader.cpp

@@ -5210,13 +5210,15 @@ static void FinishStages()
 
 	GroupActiveStages();
 
+	int deformIndex = shader.numDeforms > 0
+		? gl_shaderManager.getDeformShaderIndex( shader.deforms, shader.numDeforms )
+		: 0;
+
 	for ( size_t s = 0; s < numStages; s++ )
 	{
 		shaderStage_t *stage = &stages[ s ];
 
-		if ( shader.numDeforms > 0 ) {
-			stage->deformIndex = gl_shaderManager.getDeformShaderIndex( shader.deforms, shader.numDeforms );
-		}
+		stage->deformIndex = deformIndex;
 
 		// We should cancel overbright if there is no light stage.
 		stage->cancelOverBright = shaderHasNoLight;