I'm porting a d3d8 app to d3d9.
For testing performances, i render a simple triangle and i
export result in system memory.
- In D3D8 : render in backbuffer and transfert in sys mem
by copyrect of the backbuffer in sysmem texture surface.
- In D3D9 : render in a render target (in video mem) and
transfert in sys mem by getrendertargetdata
In result, d3d9 app is 10x slower than d3d8 app...
What's the problem?
What the implementation difference between copyrect and
P.S : with radeon 9000 mobility, GF4TI4800SE, GF4MX460