counterclockwise/clockwise orientation

OpenGL OpenGL: Basic Coding
1

Hi …

I had always thought that the default orientation for GL_POLYGON vertices is anticlockwise.
However, my compiler seems to think otherwise and produce the image only when I do clockwise.
I’m using an ANSI C++ compiler, HP-Ux.

Please help.
Thanks =>

2

Just make a call to glFrontFace(GL_CW) to set your front faces to clockwise direction.

[This message has been edited by Aster (edited 08-01-2001).]

3

I did that … my image disappear after that … sigh … dunno why …

4

Two thoughts:

  1. Are you absolutely sure you are specifying the points counter-clockwise?

  2. How do you setup your projection matrix? For instance, you do an ortho projection and make left<right or top<bottom, the coordinate system gets flipped.