6 // From section 4.3.4 of the GLSL 1.10 spec:
7 // Attribute variables are read-only as far as the vertex shader is
10 // From section 7.3 of the GLSL 1.10 spec:
11 // The following attribute names are built into the OpenGL vertex
12 // language and can be used from within a vertex shader to access
13 // the current values of attributes declared by OpenGL.
15 // attribute vec4 gl_Normal;
21 gl_Normal = vec4(0.0);