Peter there is an example of how to setup your custom geometry (even for morphing) using VBOs http://www.openscenegraph.org/projects/osg/wiki/Support/Tutorials Look at the External examples, for osgGPUMorph.3.zip
Dimi ----- Original Message ---- From: Peter Wrobrl <[email protected]> To: [email protected] Sent: Tue, June 15, 2010 9:39:13 PM Subject: [osg-users] Usage of Vertex Buffer Objects Hi, I have several questions regarding osg and the usage of VBOs. 1.) How do I ensure usage of vertex buffer object ? When I set osg::Geometry setUseVertexBufferObject to true does this allways create a VBO from the structure I passed to osg::Geometry ? E.G. In the OSG Quick Start Guide by Paul Martz we create a Quad, with four Verts, four Colors and one Normal. Setting osg::Geometry setUseVertexBufferObject to true, would this create convert the data to four Verts/Colors/Normals ? 2.) A Textured Cube has 8 Vertices and at least 12 UVs. How to create this geometry as VBO ? The right Way would be to duplicate Vertices, to have as many as UVs, but how do I create this structure and put this into a geometry ? Same approach as above from the Quick Start guide ? 3.) Lets say I have a geometry like a human, with multiple UV Shells ( UV islands, the usual approach to texture a human ), e.g. Head, Chest, Arms, Legs. How and where do I specifiy these arrays and do I need a geometry per array ? I guess I cannot set multiple Vertex/Normal/UV Arrays into one geometry, so should I stich all those arrays and pass it as one ? But this would mean that I cannot use Triangle Strips, wouldn't it ? 4.) What is the Usage of osg::VertexBufferObject ? Its not a Drawable, and osg::Geometry has no setVertexBufferObject method. It can be set into a osg::Array, where the size of each element is constraint to enums. If I understood VBOs right I can define any Data of any size as one Array element, e.g. Vertex, Normal, and UV which would be 8 floats. There is no option for 8 floats, so isn't this a limitation ? Thanks for any help and advice Cheers, ParticlePeter ------------------ Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=28969#28969 _______________________________________________ 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
