I need to visualize Gaussian Curvature of a parametric surface. there is a solution here How to visualize the Gaussian curvature of a 3D surface? but Im not sure its working because when I draw a sphere its all white but it should be red or brown(because its Gaussian curvature is positive). how can I modify that code such that for any point on the surface if its Gaussian curvature is positive it turns red and if its zero it turns to white and for negative it turns to blue. if I can do this with any other software please tell me. please help me out,(sorry for my bad English).