Hi, if found a commented X11DRV_GLX_CreateDriver in the x11drv dll, did anyone try to write a glx backend and stopped for some reason?
I was just planning to write a OpenGL backend for directdraw (i.e. using glDrawPixels, etc), as i think it would be almost as fast as dga and far more stable, but does anyone think it would be a bad idea?
Thanx Maurizio
On Thu, Mar 04, 2004 at 06:03:59AM +0100, Maurizio Monge wrote:
Hi, if found a commented X11DRV_GLX_CreateDriver in the x11drv dll, did anyone try to write a glx backend and stopped for some reason?
I was just planning to write a OpenGL backend for directdraw (i.e. using glDrawPixels, etc), as i think it would be almost as fast as dga and far more stable, but does anyone think it would be a bad idea?
Personally I think it would be a great idea, as doing this through OpenGL is even faster than doing it through DGA. A secondary benefit is that it does not require root if the user is using the DRI. We still need some sort of dumb frame buffer access around for two reasons:
1) not everyone has a card with sufficient 3D capability or any 3D capability at all 2) using 3D can use up a lot of power depending on the video card, and the user might prefer to conserve that power with slower performance.
there are probably others too. but rendering a framebuffer and 2D primitives via opengl sounds like a good plan here.
Hi, if found a commented X11DRV_GLX_CreateDriver in the x11drv dll, did anyone try to write a glx backend and stopped for some reason?
From what I know of it, this must be some code from the TransGaming DirectX
merge some time ago where they merged all the 2D stuff and left out their 3D code.
So this must be the GL initialisation of the 3D part in the HAL (ie for 3D rendering, not for 2D rendering using OpenGL).
I was just planning to write a OpenGL backend for directdraw (i.e. using glDrawPixels, etc), as i think it would be almost as fast as dga and far more stable, but does anyone think it would be a bad idea?
Did you do some benchmarks on the glDrawPixels call to see the speed of it (try to compare it with the same code, but using the texture engine) ? And how do you plan to handle Direct3D with this back-end ?
Anyway, I had something like that planned for a long time, but using textures rather than glDrawPixels (for one reason : some hardware has paletted texture support, which means that we can remove all colour-conversion code as it will be handled at worst by the driver, at best by the graphics hardware).
One could also accelerate Blts with this, but this leads to another can of worms : you won't have an exact copy of the frame-buffer in application memory anymore (thus would need to use glReadPixels which is even slower than glDrawPixels :-) ).
Lionel
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Lionel Ulmer -
Maurizio Monge -
Ryan Underwood