01/21/2003
15-462 Computer Graphics I
2
Surface Orientation (Clarification)
•Right-hand rule
•Triangle strip drawn 0-1-2, 2-1-3, 2-3-4, etc.
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•All triangles face same direction (here: back)
•Similarly for quad strips 0-1-3-2, 2-3-5-4, etc.
•Orientable surfaces; discard back faces:
•glEnable(GL_CULL_FACE);
•glCullFace(GL_BACK);   /* do not draw back faces */