On Sat, Nov 7, 2009 at 7:50 PM, Kripken <[email protected]> wrote: > > On Sat, Nov 7, 2009 at 7:36 PM, Toni Alatalo <[email protected]> wrote: >> >> Regarding Cg, it may be that the current Naali uses some shader written >> in cg by default (perhaps the water?), but even if that's the case it >> doesn't mean that it would be a somehow integral part of the >> application. From an engine perspective, shaders are just content (like >> an image), and what content you use is more a configuration than a >> programming issue. > > > In theory yes, but if you have such things then (1) Ogre will not fail > gracefully, in my experience, if it cannot load the Cg plugin and is asked > to show a Cg shader, and (2) even if you do create a custom graceful failure > system here (by modding Ogre? Or is there a better way?), to e.g. use a > 'blank' shader instead of Cg shaders, you may end up with a very different > experience in a non-Cg-enabled viewer (depending on how important the Cg > shaders are). > > To make my earlier question more technical: I'd be interested to know, what > are Naali shaders written in - new ones you guys are writing, and ones that > exist in Ogre libraries you are using (if any)? > > - kripken
Turns out our sky effects, which are done by Caelum (http://www.ogre3d.org/wiki/index.php/Caelum) use Cg for their shader programs: http://dev.realxtend.org/gf/project/viewerdeps/scmsvn/?action=browse&path=%2Ftrunk%2FCaelum%2Fmain%2Fresources%2F I run a mostly stock Fedora 11, but I have FusionRPMs installed, so that's how I got it without really thinking where it came from. Some basic research: http://developer.nvidia.com/object/cg_compiler_code.html. It appears the compiler front-end is open, but actual code generation is not, making the whole thing effectively not open. So anyone is freely able to to build and run Naali with Caelum skies, but if one has a principled stand against ever installing a binary that doesn't come with source, one can easily build Naali, including as a native package for Fedora or Debian, without Caelum, for slightly less fancy skies but morally correct code. In the mean time, if anyone has a more free option that Caelum or Cg, please me us know. It appears there is a recent effort to convert to GLSL (and HLSL presumedly following), demonstration that it would be too much work, but the effort appears to have fallen short: http://www.ogre3d.org/addonforums/viewtopic.php?f=21&t=10487 All in all, I don't think RMS is losing much sleep over this problem at the moment. Cheers, --~--~---------~--~----~------------~-------~--~----~ http://groups.google.com/group/realxtend http://www.realxtend.org -~----------~----~----~----~------~----~------~--~---
