Stencil buffer | GameDev.net

Original Post

Jan 31, 2004 at 5:17 AM

I want to be able to get values out of the depth buffer so i can speed up my terrain tile picker by using D3DXVec3Unproject. I need the depth of the pixel that the mouse is over so i can parse unproject the distance from the screen. So can a stencil buffer be used for this and if so how can i do it

noVum

Jan 31, 2004 at 5:22 AM

No. And you should NOT read from VRAM ever (at least not till PCI Express arrives afaik)
Doing so will be very slow. Line/Highmap intersection in software is not that difficult

kapru

Author

kapru

Jan 31, 2004 at 6:25 AM

Ok then is there any way to use D3DXVec3Unproject to do what i want

noVum

Jan 31, 2004 at 9:12 AM

Yes. Reading from the Z-buffer. But as I told you, I strongly disadvise you from doing so.

Topic Locked