diff --git a/wadsrc/static/shaders/shaderkey.glsl b/wadsrc/static/shaders/shaderkey.glsl
index 9d270e5d2..a7ed45b90 100644
--- a/wadsrc/static/shaders/shaderkey.glsl
+++ b/wadsrc/static/shaders/shaderkey.glsl
@@ -33,9 +33,9 @@
 	#define SK1_LIGHTMODE_VANILLA		2
 	#define SK1_LIGHTMODE_BUILD			3
 #define SK1_LIGHTBLENDMODE			(3  << 27)
-	#define SK1_LIGHT_BLEND_CLAMPED					1
-	#define SK1_LIGHT_LIGHT_BLEND_COLORED_CLAMP		2
-	#define SK1_LIGHT_BLEND_UNCLAMPED				3
+	#define SK1_LIGHT_BLEND_CLAMPED					0
+	#define SK1_LIGHT_LIGHT_BLEND_COLORED_CLAMP		1
+	#define SK1_LIGHT_BLEND_UNCLAMPED				2
 #define SK1_LIGHTATTENUATIONMODE	(1  << 29)
 //#define SK1_USE_LEVELMESH			(1  << 30)
 #define SK1_FOGBALLS				(1  << 31)