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A05087
12-18-2002, 12:53 AM
what is the difference in zooming using glPixelZoom and using
glTranslatef(0.0, 0.0,zoom); where zoom can be increased and decreased?

Relic
12-18-2002, 01:31 AM
glPixelZoom works for glDrawPixels and glCopyPixels only and is screen coordinate based. It simple scales the bitmap size.
glTranslate moves geometry in z direction. Depending on the current coordinate system's orientation this might not even result in a zoom effect.
A real zoom effect for 3D graphics needs to be done by changing the field-of-view e.g. in the gluPerspective call.

A05087
12-18-2002, 01:34 AM
Would gluPerspective be the best for the resolution of the image?


Originally posted by Relic:
glPixelZoom works for glDrawPixels and glCopyPixels only and is screen coordinate based. It simple scales the bitmap size.
glTranslate moves geometry in z direction. Depending on the current coordinate system's orientation this might not even result in a zoom effect.
A real zoom effect for 3D graphics needs to be done by changing the field-of-view e.g. in the gluPerspective call.