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bubbaJr
02-16-2005, 07:07 AM
What the heck is Bit Blit? I wouldn't be asking here in this forum, except I did a search on it in 'coding beginners' and nothing was found.

Relic
02-16-2005, 07:51 AM
Because there is no OpenGL function named so.

A blt is a block transfer of data,
BitBlt is a usual name for block transfer of arbitrary rectangular binary image data.

Here is a Win32 GDI function doing this:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/gdi/bitmaps_0fzo.asp

The nearest OpenGL equivalents would be glCopyPixels, glReadPixels and glDrawPixels, but there are a lot of differences to the above.

bubbaJr
02-16-2005, 08:04 AM
In the past, I've tried using glCopyPixels, glReadPixels, glDrawPixels in attempts to rapidly move a 640 x 480 region of pixels to a memory buffer, then back again. Hopefully BitBlt would do this better than I could make glCopy/Read/DrawPixels do it.