Modify Program 13.2 so that it deletes every other primitive, or every fourth primitive (rather than every third primitive), and observe the effect on the resulting rendered torus. Also, try changing the dimensionality of the instantiated torus to a value that is not a multiple of three (such as 40), while still deleting every third primitive. There are many possible effects.

Program 13.2

// inputs, outputs, and uniforms as before void main (void) { if (mod(gl_PrimitivelDIn,3) != 0 ) { for (int i=0; i