Hi Robert, CLAMP_TO_BORDER is used so that if the shader lookup goes beyond the bounds of the texture it doesn't get inappropriate data i.e back with an alpha of zero at least will be culled by most shaders so will allow the volume data to stand on it's own.
I can also see value in CLAMP_TO_EDGE as an option as well as controlling the border colour when one is using CLAMP_TO_BORDER. We could potentially could add an option into the osgVolume::ImageLayer to provide hints to the texture setup. Robert. On 13 February 2013 16:23, Robert Spearman <r...@digitaliseducation.com> wrote: > In openscenegraph-3.0.0/OpenSceneGraph/src/osgVolume/RayTracedTechnique.cpp > the 3D texture is being clamped to a border color of (0,0,0,0). > > It seems to me this should be CLAMP_TO_EDGE rather than CLAMP_TO_BORDER, > since using a border color not in the actual texture is completely arbitrary. > I'm using my own shaders and seeing a lot of unwanted effects from this > border color, such as unwanted color darkening and inability to define my own > alpha mapping. > > What do you think? I don't see how it would cause any problems. > > Thanks, > > Rob > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=52653#52653 > > > > > > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
