Hi Oliver, This is classic problem with the use of the depth buffer w.r.t transparency, and affects all OpenGL and D3D apps. The OpenSceneGraph sorts based on the distance of the center of drawables bouding box and the eye point. Sorting on polygons is not done as its would be incredibly, incredibly inefficient in terms of performance.
All is not lost though. You can use multipass techniques in some case, and breaking the model in small chunks is also quite effective. It just so happens that for a sphere you can render it twice, first render with the front faces culled, then afterwards with the back faces culled. The osg::ShapeDrawable has support for this two pass rendering. Robert. On 7/27/06, Oliver Kutter <[EMAIL PROTECTED]> wrote:
Hi, I have a question concerning the transparency sorting in osg. I think, the sorting is done over all objects (nodes) and not over all polygons, isn't it. And I don't know how it is done in OpenGL. But, is there any way in osg to sort the polygons manually or automatically? Here is a screenshot which shows the problem: http://getwww.uni-paderborn.de/~kutter/TransparentBall.jpg <http://getwww.uni-paderborn.de/%7Ekutter/TransparentBall.jpg> bye Oliver _______________________________________________ osg-users mailing list [email protected] http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/
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