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dhoffman
04-20-2001, 01:06 PM
What is the difference between glFrustum and glutPerspective? For some reason, I could never get things to look right with glFrustum, but when I used comparable dimensions with glutPerspective everything looked great. Also, something I haven't tried yet but just thought of, if I set the far to to be so far away that an object never appears to be clipped out, but to just fade away as it becomes too small to see I have the feeling it's going to screw up the way objecs up close look. I'm not sure why I feel that way considering I haven't tried it yet, but I thought I would ask in case anyone answers before I try it. So what I really want to say is, if I set the far to be nearly infinitely far away, how else will that effect the viewing perspective, particularly for objects up close? How should I set things up so that objects become to small to see before being clipped out but so that objects up close look correct?

zed
04-20-2001, 06:08 PM
>>What is the difference between glFrustum and glutPerspective?<<

gluPerspective is just a wrapper for glFrustum. why have it then? because as you yourself have found out , it is easier to visualize.

>>if I set the far to be nearly infinitely far away, how else will that effect the viewing perspective, particularly for objects up close?<<

you'll most likely end up getting terrible depth artifacts. check the depth section of the faq for more info