Re: [R200]Problems with HW TCL in Tuxracer and PPRacer
Michel Dnzer wrote: On Thu, 2005-03-03 at 20:22 +0100, Roland Scheidegger wrote: Michel Dnzer wrote: On Wed, 2005-03-02 at 16:11 +0100, Marcello Maggioni wrote: When using HW TCL in Tuxracer or PPRacer (that is essentially the same game) with my Radeon 8500 with DRI drivers dated 25 february 2005 you can see that there are problems with light reflection in those places where there's ice (for example in the first stage that is full of ice pools ) . You mean the flickering? That's probably Z fighting, most likely a problem in the game itself. You should bring this up with the PPRacer project, now that there's active development there... No, this is a result of the tcl fallback used for the GL_SPHERE_MAP texgen (it is z fighting I guess). Sure, but Brian told me the application has to be prepared for and deal with this. Really? Interesting. What does it have to do? I never really understood what exactly caused the z-fighting issues with the fallbacks. Roland --- SF email is sponsored by - The IT Product Guide Read honest candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_ide95alloc_id396op=click -- ___ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
Re: [R200]Problems with HW TCL in Tuxracer and PPRacer
On Thu, 2005-03-03 at 20:22 +0100, Roland Scheidegger wrote: Michel Dnzer wrote: On Wed, 2005-03-02 at 16:11 +0100, Marcello Maggioni wrote: When using HW TCL in Tuxracer or PPRacer (that is essentially the same game) with my Radeon 8500 with DRI drivers dated 25 february 2005 you can see that there are problems with light reflection in those places where there's ice (for example in the first stage that is full of ice pools ) . You mean the flickering? That's probably Z fighting, most likely a problem in the game itself. You should bring this up with the PPRacer project, now that there's active development there... No, this is a result of the tcl fallback used for the GL_SPHERE_MAP texgen (it is z fighting I guess). Sure, but Brian told me the application has to be prepared for and deal with this. -- Earthling Michel Dnzer | Debian (powerpc), X and DRI developer Libre software enthusiast| http://svcs.affero.net/rm.php?r=daenzer --- SF email is sponsored by - The IT Product Guide Read honest candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_ide95alloc_id396op=click -- ___ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
Re: [R200]Problems with HW TCL in Tuxracer and PPRacer
Michel Dnzer wrote: On Wed, 2005-03-02 at 16:11 +0100, Marcello Maggioni wrote: When using HW TCL in Tuxracer or PPRacer (that is essentially the same game) with my Radeon 8500 with DRI drivers dated 25 february 2005 you can see that there are problems with light reflection in those places where there's ice (for example in the first stage that is full of ice pools ) . You mean the flickering? That's probably Z fighting, most likely a problem in the game itself. You should bring this up with the PPRacer project, now that there's active development there... No, this is a result of the tcl fallback used for the GL_SPHERE_MAP texgen (it is z fighting I guess). Someday we should figure out why it doesn't work correct in the first place probably (if you kill the fallback, you can clearly see it's not quite correct in ppracer), though it wouldn't hurt to make the fallbacks work better neither (r100 has afaik the same problem, and it can't be fixed by not using a fallback since it doesn't support GL_SPHERE_MAP texgen). Roland --- SF email is sponsored by - The IT Product Guide Read honest candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_ide95alloc_id396op=click -- ___ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
Re: [R200]Problems with HW TCL in Tuxracer and PPRacer
Roland Scheidegger wrote: Michel Dnzer wrote: On Thu, 2005-03-03 at 20:22 +0100, Roland Scheidegger wrote: Michel Dnzer wrote: On Wed, 2005-03-02 at 16:11 +0100, Marcello Maggioni wrote: When using HW TCL in Tuxracer or PPRacer (that is essentially the same game) with my Radeon 8500 with DRI drivers dated 25 february 2005 you can see that there are problems with light reflection in those places where there's ice (for example in the first stage that is full of ice pools ) . You mean the flickering? That's probably Z fighting, most likely a problem in the game itself. You should bring this up with the PPRacer project, now that there's active development there... No, this is a result of the tcl fallback used for the GL_SPHERE_MAP texgen (it is z fighting I guess). Sure, but Brian told me the application has to be prepared for and deal with this. Really? Interesting. What does it have to do? I never really understood what exactly caused the z-fighting issues with the fallbacks. One of the appendices of the OpenGL Programming Guide discusses invariance. The basic idea is that certain kinds of OpenGL state changes should not result in any difference in the final rasterization, in terms of fragment x,y,z and/or color. For example, changing GL_DEPTH_FUNC from GL_LESS to GL_GEQUAL should have no effect on the generated fragments. In other cases, a stage change such as enabling/disabling texgen may require that the OpenGL implementation use totally different vertex processing paths (hardware vs. software, perhaps) and the set of fragments generated will be different. That's allowable. The application programmer has to be aware of this if they're relying on some sort of repeatability. That said, I don't know exactly what Tuxracer is doing. -Brian --- SF email is sponsored by - The IT Product Guide Read honest candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_ide95alloc_id396op=click -- ___ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
[R200]Problems with HW TCL in Tuxracer and PPRacer
When using HW TCL in Tuxracer or PPRacer (that is essentially the same game) with my Radeon 8500 with DRI drivers dated 25 february 2005 you can see that there are problems with light reflection in those places where there's ice (for example in the first stage that is full of ice pools ) . If you disable HW TCL the problem is solved , but you get problems with TUX textures (don't know why :) ) Bye Marcello --- SF email is sponsored by - The IT Product Guide Read honest candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595alloc_id=14396op=click -- ___ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
Re: [R200]Problems with HW TCL in Tuxracer and PPRacer
On Wed, 2005-03-02 at 16:11 +0100, Marcello Maggioni wrote: When using HW TCL in Tuxracer or PPRacer (that is essentially the same game) with my Radeon 8500 with DRI drivers dated 25 february 2005 you can see that there are problems with light reflection in those places where there's ice (for example in the first stage that is full of ice pools ) . You mean the flickering? That's probably Z fighting, most likely a problem in the game itself. You should bring this up with the PPRacer project, now that there's active development there... -- Earthling Michel Dnzer | Debian (powerpc), X and DRI developer Libre software enthusiast| http://svcs.affero.net/rm.php?r=daenzer --- SF email is sponsored by - The IT Product Guide Read honest candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_ide95alloc_id396op=click -- ___ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
