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gordon1
01-20-2007, 02:47 PM
Is the GL_TRIANGLE_FAN structure simply for coding convenience, or does it internally create a more optimized set of triangles than if each triangle were created separately?

Thanks.

RGHP
01-20-2007, 04:09 PM
It's more efficient. Remember that OpenGL just give you primitives. If that would be just for coding convenience, It would come implmented by glu.


Well now I have my questions: Is there any forum of OpenGL in Spanish?

Zengar
01-20-2007, 04:50 PM
My guess is that most drivers transform them into triangles, or triangle strips at best. But you never know :-)

ZbuffeR
01-21-2007, 02:59 PM
With triangle fans, you need only need to specify 1 vertex for each triangle (after the first).
So it mean less data to send and store, and less T&L computations if the card makers made their job correctly.

V-man
01-22-2007, 02:03 AM
Originally posted by RGHP:
It's more efficient. Remember that OpenGL just give you primitives. If that would be just for coding convenience, It would come implmented by glu.
Not necessarily. QUADS are provided as a convenience and other functions like glMultMatrix, glRotate, glTranslate, glScale.

You can just ignore GLU since it's very out of date.