OpenGL: add vertices with vertex shader

Question

Please tell me how can I add a new vertex in the vertex shader?

Answer 1

A vertex shader converts only vertices. If you need to derive additional geometry based on input vertices, you will need a geometric shader .

Answer 2

You can add vertices using the geometric shader http://www.opengl.org/wiki/Geometry_Shader

"GS can create new primitives, unlike vertex shaders, which are limited to a 1: 1 ratio to output."

Answer 3

You can not. What geometry shaders for.