DrawMesh Lacking luster

Sorry, after repeatedly testing the code and failing, I can only seek help from the teachers. I inherit the DisplayConduit class and display a mesh, which has no glossy shadows and looks like a flat surface. What I want is an effect like a Grasshopper (image B). Can I achieve it? Excuse me.

Like here?

I have solved it. Thank you very much for your kind help in resolving my doubts. Thank you again.