Please help me - it seems that wglAllocateMemoryNV works in a strage way
… it an allocate only one block of AGP
memeory or 4 blocks of video memory … any subsequent allocations fail.
for agp memory I use wglAllocateMemoryNV ( 16384, 0, 0, 0.5f );
for video memory I use wglAllocateMemoryNV ( 16384, 0, 0, 1 );
the size does not matter - it easily allocates 8 Mb block in AGP memory, but
it cannot allocate two of them if they are 4096;
Using GeForce 256 DDR ( Asus V6800 ) with 32Mb ram, nvidia reference bios
2.10.02.04.00 with sideband addressing fix
and nvidia reference drivers v 6.18.
Also, it seems that video memory is a ligned on size of 4608 … it is equal
to 4096 + 512 … Just interested why such granularity ( not page ) ?
As it turns out, the answer may not be all that helpful.
There are a number of OS and chipset issues that muddy the waters here. The short answer is that if you want to write well-supported VAR code, you should allocate only one large chunk (per memory type). Your request is more likely to succeed if you make it before allocating (specifying) textures.
I knew it
At least, I was thinking on creating geometry memory manager - it keeps clear that it is required.
Thanks for help, cass
Last question - besides the spec - is there a way to get amount of available AGP and video memory, suitable for wglAllocateMemoryNV ? Seems there it is not, but just wanna be sure