a shtit question about data in vram

If i have datas in the vram, is it better to use them directly in the vram or may I need to have a copy in the ram ?
does the access is quick enough ?



Assuming you’re talking about textures(please be more specific) keeping copies in system RAM is up to you.You can do it if you need them but it won’t matter speedwise since the driver will use its own(the one you uploaded) data anyway.Also bear in mind that the driver might(read ropably does) keep system ram images for itself.

And again try to be more specific when you post questions.


it was not a texturing question.

well i allocate into nvidia memory the data as vertices, normals, colors and texels of my rendering.

I would like to know if i could safely, quickly use these data in order to do other things than drawing. I need to know some informations almost about the vertices of my objects. so, i though that not having these vertices (and sometimes the other datas) both in graphic memory and RAM would be greater.

thanx for any comment.


Never read stuff from agp/video ram. Keep a shadowed copy of your verts/norms etc. in system memory if you need to reference their contents in your app.

there might be a good reason for that. although, it could be very interresting to use them because of the speed. it stinks having data in double !

now, OK, thanx for your reply.