diff --git a/src/image.c b/src/image.c
index 7d859587..b7e8a6d5 100644
--- a/src/image.c
+++ b/src/image.c
@@ -7,9 +7,12 @@
 
 #include "tophat.h"
 
+#ifndef GL_UNSIGNED_INT_8_8_8_8 
+#define GL_UNSIGNED_INT_8_8_8_8 0x8035
+#endif
+
 #ifdef _WIN32
 #define glActiveTexture glActiveTextureCHEW
-#define GL_UNSIGNED_INT_8_8_8_8 0x8035
 #endif
 
 extern th_global *thg;