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[NEED HELP] Radeon 9550 broken warpzones: bad OpenGL 2.0 implementation? - Printable Version

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+--- Thread: [NEED HELP] Radeon 9550 broken warpzones: bad OpenGL 2.0 implementation? (/showthread.php?tid=3759)



Radeon 9550 broken warpzones: bad OpenGL 2.0 implementation? - edh - 12-16-2012

I managed to pick up an old computer for free a few days ago from a friend who was getting rid of it. Broken HDD and horrid case and PSU but still some usable parts for nothing. Big Grin

It has a Radeon 9550 graphics card, basically an underclocked 9600 but also was confusingly marketed as the X1050 as well. Darkplaces reports that it supports OpenGL 2 when used under Windows XP with the ATI drivers.

Warpzones do not render correctly with this card, a scene here from Glow Arena to demonstrate:


.jpg   xonotic20121216180809-00.jpg (Size: 25.73 KB / Downloads: 31)

For a start there is some serious draw order issue going on with everything viewed through the warpzone. This also causes big overdraw and hence it's slow as well as confusing. Sometimes the actual angle/position of the warpzone is offset such that everything the other side appears shifted too.

Now I'm not expecting anything to be fixed here really as I'm pretty certain it's a broken OpenGL 2.0 implementation and I'd blame ATI for that. I just wanted to point this out as it will most likely effect other r300 Radeons too. I was going to have a go under Linux with the free drivers to see if they manage any better.

Obviously I've tried lots of things with VBO, occlusions and reflection detail levels to no avail.

To mitigate against this (and other OpenGL 2.0) problems, an OpenGL 1.3 path for the reflections would be the best help, if perhaps a little out of date now as anything modern should run OpenGL 2.0 with no problems.