OpenGL GL_POLYGON concave polygon doesn't color in

Question

I have a problem when I try to use Polygon in OpenGL. I don\'t know how to explain this but all my vertices are connected with the beginning one. The problem happens when I

Answer 1

GL_POLYGON is only for convex polygons.

For concave polygons you have at least two options:

1. Triangulate the polygon and use GL_TRIANGLES.

2. Use the stencil buffer trick.