Strange problem after using a third party library

OpenGL OpenGL: Advanced Coding
1

[ATTACH=CONFIG]924[/ATTACH]

Right is my 3D model.
It appears as the left after using a third party.
I have no idea what the third party setting will lead the problem.
Someone can give me a help?

Thanks.

James Xu

2

It looks like differences in winding order (clockwise versus counter-clockwise), back-face culling, or Z direction (positive Z into screen versus out of screen).

3

It is caused by back-face culling.
Without using the third party lib, it’s ok that I use glCullFace(GL_BACK).
With the third party lib, it’s ok if I change the GL_BACK to GL_FRONT.
How to switch it back?

Thanks.
James Xu

4

I have fix the problem with glFrontFace(GL_CCW);

Thanks.
James Xu