diff --git a/plant-eyes/shaders/toon.frag.glsl b/plant-eyes/shaders/toon.frag.glsl
index cd0c490..f19a0fa 100644
--- a/plant-eyes/shaders/toon.frag.glsl
+++ b/plant-eyes/shaders/toon.frag.glsl
@@ -25,7 +25,7 @@ void main()
     if (lambert > 1.0-HighlightSize) colour = HighlightColour;
     if (lambert < ShadowSize) colour = ShadowColour;
     if (dot(n,v) < OutlineWidth) colour = vec4(0,0,0,1);
-    if (dot(n,v) < 0) colour = MidColour*texture2D(BaseMap, T);
+    if (dot(n,v) < 0.0) colour = MidColour*texture2D(BaseMap, T);
 
     gl_FragColor = colour;
 }