diff --git a/include/osg/BlendFunc b/include/osg/BlendFunc
index d8fcf47eb..05ed879bb 100644
--- a/include/osg/BlendFunc
+++ b/include/osg/BlendFunc
@@ -77,6 +77,8 @@ class SG_EXPORT BlendFunc : public StateAttribute
             SRC_ALPHA                = GL_SRC_ALPHA,
             SRC_ALPHA_SATURATE       = GL_SRC_ALPHA_SATURATE,
             SRC_COLOR                = GL_SRC_COLOR,
+            CONSTANT_COLOR           = GL_CONSTANT_COLOR,
+            ONE_MINUS_CONSTANT_COLOR = GL_ONE_MINUS_CONSTANT_COLOR,
             CONSTANT_ALPHA           = GL_CONSTANT_ALPHA,
             ONE_MINUS_CONSTANT_ALPHA = GL_ONE_MINUS_CONSTANT_ALPHA,
             ZERO                     = GL_ZERO