-//#define OS2RGB(r,g,b) ((ULONG ((BYTE) (r) | ((UINT) (g) << 8)) | (((ULONG)(BYTE)(b)) << 16)))
-#define OS2RGB(r,g,b) ((unsigned long)r<<16|(unsigned long)g<<8|(unsigned long)b)
+// #define OS2RGB(r,g,b) ((ULONG ((BYTE) (r) | ((UINT) (g) << 8)) | (((ULONG)(BYTE)(b)) << 16)))
+*/
+#ifndef OS2RGB
+# define OS2RGB(r,g,b) ((unsigned long)r<<16|(unsigned long)g<<8|(unsigned long)b)
+#endif