Hi Jason, This is a missing feature rather than a bug - with GLSL you have to implement everything yourself, and one can't second guess all different combinations of usage that users might wish to use. In the case of clip planes, they simply aren't support by the current rev of osgVolume::RayTracedTechnique.
Support in osgVolume for clip planes is a possibility, but will require new shaders to be written to explictly do the clipping in the ray tracing fragment shader. Feel free to implement your own VolumeTechnique to tackle this. One thing I have been considering for osgVolume is that support for a two pass approach where you render the front face of the volume to a depth texture, then use this depth texture when do the ray tracing to provide an ability to render a non box shaped volume. This technique would still require the enclosing shape to be a convex hull for proper rendering but would enable a lot more flexibility with the the type of clipping you could have. Robert. On Thu, Jul 2, 2009 at 5:19 PM, Jason Baurick<[email protected]> wrote: > Hi, > > I've encountered (what I think of as) a bug when working with osgVolume. If > you are using the RayTracedTechnique you cannot use user defined clip > planes. According to the GLSL spec you have to define the gl_ClipVertex in > your vertex shader, however it is not defined. Is this intentional or is it > a bug? If it is a bug is there some process I need to go about to submit > bug report? Also if I wanted to submit a patch to fix it how would I go > about that? > > Thanks > > -- > --Jason Baurick > > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
