6 * From page 20 (page 26 of the PDF) of the GLSL 1.20 spec:
8 * "Arrays know the number of elements they contain. This can be obtained
9 * by using the length method:
11 * a.length(); // returns 5 for the above declarations
13 * The length method cannot be called on an array that has not been
22 gl_Position = vec4(a.length());