diff --git a/OpenGL/Sfx/shader_platform.sl b/OpenGL/Sfx/shader_platform.sl
index bf5785e3..8a8681b2 100644
--- a/OpenGL/Sfx/shader_platform.sl
+++ b/OpenGL/Sfx/shader_platform.sl
@@ -5,6 +5,10 @@
 
 #ifndef __cplusplus
 
+#ifndef BOTTOM_UP_TEXTURE_COORDINATES
+#define BOTTOM_UP_TEXTURE_COORDINATES 1
+#endif
+
 #define USE_D3D_REF_MODE 0
 
 // This should be passed to the compiler, do we use it? (gaussian.sfx)