Re: measuring video memory

New Guy wrote:

This is a FAQ, look for the detailed awnser there. google "OpenGL
FAQ site:opengl.org"

1) What function call (if any) can I use to see how much
*total* VRAM a graphics card has?

There is none.

2) And what call to see how much *available* VRAM ? (ie, VRAM
not used by frame buffers, pbuffers, and textures).

There is none.

OpenGL will swap out textures from VRAM to system memory if
you're running low on VRAM. Of course this comes with the same
drawback, that swapping always brings: A huge performance hit.

There are ways to determine, if a texture will fit into
the "resident" area of the VRAM, before you upload (using proxy
textures) and you can test, if a texture has been swapped. But
there's no way to tell, how much space is left in VRAM for
textures. Actually such a value makes no sense with OpenGL
anyway, since you can't lock the video hardware exclusively, so
by starting other programs, which use the 3D hardware will
change the situation completely.

Wolfgang Draxinger
--
E-Mail address works, Jabber: hexarith@xxxxxxxxxx, ICQ: 134682867

.

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