Aapo Tahkola wrote: > On Sun, 13 Aug 2006 02:17:40 +0200 > Rune Petersen <[EMAIL PROTECTED]> wrote: > >> Roland Scheidegger wrote: >>> Rune Petersen wrote: >>>> Roland Scheidegger wrote: >>>> fragment.position input is not implemented yet. fglrx driver parses >>>> it from VP to FP via a texcoord route. I've been hitting my head on >>>> this for some time. Only got as far as only getting a soft lockup >>>> which isn't very useful. >>> That kinda makes sense. On r200 you could already pass vertex data >>> to the fragment registers (but you couldn't use position as input), >>> so the data was interpolated by the texcoord interpolator but >>> texture lookup was disabled (see the ATI_fs spec / r200 dri >>> implementation). At first sight looks like a similar mechanism >>> might be used by r300 I guess, interpolating position or texcoords >>> isn't too different is it? >>> >> I've had been looking into this, and the vertex shader is supplying >> the position to the fragment shader as a texcoord, the only apparent >> difference in shader setup between a position and a real texcoord, is >> a real texcoord is supplied as input for the vertex shader. >> >> >> I would really like to capture the vertex program of >> program/fp/tri-depth and the fglrx driver. >> >> But I'm betting the vertex shader is capable of writing to a texcoord. >> All I need is a safe way for the vertex shader code to know if the >> fragment shader needs the position. >> >> Any help with this would be great. > > Bug #8056 patch can do this. Take a look at r300_select_vertex_shader(). >
Thank you. Getting wpos to the fragment shader is not too reliable atm, but something strange: Only x & y are valid for hpos in the vertex shader.. z = 0 & w = 1 as you would expect if they weren't set... Am I missing something obvious? Rune Petersen ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys -- and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV -- _______________________________________________ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
