Fixed blend mode and alpha issues when drawing bitmaps that use textures

Author: KarimAkra

flixel/graphics/tile/FlxDrawQuadsItem.hx

@@ -118,11 +118,13 @@ class FlxDrawQuadsItem extends FlxDrawBaseItem<FlxDrawQuadsItem>
 		// TODO: catch this error when the dev actually messes up, not in the draw phase
 		if (shader == null && graphics.isDestroyed)
 			throw 'Attempted to render an invalid FlxDrawItem, did you destroy a cached sprite?';
-		
+
 		final shader = shader != null ? shader : graphics.shader;
 		shader.bitmap.input = graphics.bitmap;
 		shader.bitmap.filter = (camera.antialiasing || antialiasing) ? LINEAR : NEAREST;
 		shader.alpha.value = alphas;
+		final isTexture:Bool = !graphics.bitmap.readable;
+		shader.isTexture.value = [isTexture];
 
 		if (colored || hasColorOffsets)
 		{
@@ -146,4 +148,4 @@ class FlxDrawQuadsItem extends FlxDrawBaseItem<FlxDrawQuadsItem>
 		parameter.value[0] = value;
 	}
 	#end
-}
+}

flixel/graphics/tile/FlxGraphicsShader.hx

@@ -12,7 +12,7 @@ class FlxGraphicsShader extends GraphicsShader
 	", true)
 	@:glVertexBody("
 		openfl_Alphav = openfl_Alpha * alpha;
-		
+
 		if (hasColorTransform)
 		{
 			if (openfl_HasColorTransform)
@@ -30,27 +30,32 @@ class FlxGraphicsShader extends GraphicsShader
 	@:glFragmentHeader("
 		uniform bool hasTransform;  // TODO: Is this still needed? Apparently, yes!
 		uniform bool hasColorTransform;
+		uniform bool isTexture;
 		vec4 flixel_texture2D(sampler2D bitmap, vec2 coord)
 		{
 			vec4 color = texture2D(bitmap, coord);
+
+			if (isTexture)
+				color.rgb *= color.a;
+
 			if (!(hasTransform || openfl_HasColorTransform))
 				return color;
-			
+
 			if (color.a == 0.0)
 				return vec4(0.0, 0.0, 0.0, 0.0);
-			
+
 			if (openfl_HasColorTransform || hasColorTransform)
 			{
 				color = vec4 (color.rgb / color.a, color.a);
 				vec4 mult = vec4 (openfl_ColorMultiplierv.rgb, 1.0);
 				color = clamp (openfl_ColorOffsetv + (color * mult), 0.0, 1.0);
-				
+
 				if (color.a == 0.0)
 					return vec4 (0.0, 0.0, 0.0, 0.0);
-				
+
 				return vec4 (color.rgb * color.a * openfl_Alphav, color.a * openfl_Alphav);
 			}
-			
+
 			return color * openfl_Alphav;
 		}
 	", true)