Factor out back color

PortabilityLayer/ResolveCachingColor.h

@@ -0,0 +1,24 @@
+#pragma once
+
+#include "RGBAColor.h"
+
+namespace PortabilityLayer
+{
+	class ResolveCachingColor
+	{
+	public:
+		ResolveCachingColor(const RGBAColor &color);
+		ResolveCachingColor(const ResolveCachingColor &color);
+
+		uint8_t Resolve8(const RGBAColor *palette, unsigned int numColors);
+
+	private:
+		RGBAColor m_rgbaColor;
+
+		uint16_t m_resolved16;
+		uint8_t m_resolved8;
+
+		bool m_isResolved16;
+		bool m_isResolved8;
+	};
+}