Hi Martin, The blending depends upon the shader used into osgVolume, ones like the isosurface ones don't even do any blending. The current shaders that do blending do it from back to front, if you want to do it the other way around then that's fine, but even if the existing blending shaders did it from front to back the code would be embedded in the shader itself and not reusable in the way you are wanting. So in the end it'll always be down to your own shaders to do what you need to do.
Robert. On Sat, May 8, 2010 at 1:45 PM, Martin Panknin <[email protected]> wrote: > Hi, > > I'm currently looking into the osgVolume nodekit and the osgVolume example as > I'm trying to implement a simple volume raycasting shader in osg, which I > have previously written in Rendermokey. > > The shader calculates the direction for the ray by rendering the front and > back faces of a unit cube. The difference between the faces is stored in a > texture and serves for the direction look up. I'm using front to back > blending as I need to integrate early ray termination due to performance > reasons. > > As far as I understand it by looking at the source, the osgVolume example > uses back to front blending and I'm wondering, if the functionality for front > to back blending is already available in osgVolume. What would be the best > way for generating the direction texture in this case? Can this be done > directly in osg or do I have to use for example osgPPU in order to setup my > rendertargets? > > Any hints are greatly appreciated. > > Thank you! > > Cheers, > Martin > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=27683#27683 > > > > > > _______________________________________________ > 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
