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Phil.Tessier
12-31-2003, 11:03 AM
I'm new here.

I'm seeing glDrawPixels generate an Access Violation when drawing certain images at zoom factors between 0 and 1 (e.g. 0.5).

Zoom factors of 1 or greater are no problem for any images, and smaller images (i.e., 256x256) have no problem with reducing scale factors, but larger images (i.e., 1024x1024) are very unreliable at reducing scale factors.

I'm using SGI OpenGL for Windows Version 1.1. Has anyone else seen this? Does anyone have suggestions?

I've set up an exception handler for this, so that my program can continue even if glDrawPixels crashes. Sometimes, when the exception is thrown, nothing is drawn into the buffer. Other times, a partial image has been placed into the buffer.

The address reported for the access violation is (apparently) always past the end of the bit buffer a small number of rows.

Thanks in advance,
Phil