Hi Wojtek, You've come across the wacky world of position OpenGL state. Normal OpenGL state like modes and textures etc are invarient of the current modelview matrix, not so for positional state these use the current modelview matrix to position themselves so its become crucial that you apply a specific modelview matrix before you apply the state otherwise it's position will vary widely according to what modelview matrices just so happens to be applied.
Examples of positional state are glLight, glClipPlane and glTexGen EYE_LINEAR. glTexGen OBJECT_LINEAR is not positional though so it doesn't matter when its applied - its just like ordinary OpenGL state. So how does the scene graph handle this positional state? We have to anchor in space using a special node, osg::LightSource, osg::ClipLane and osg::TexGenNode all exist for this purpose. Robert. On Thu, Mar 27, 2008 at 9:16 AM, Wojciech Lewandowski <[EMAIL PROTECTED]> wrote: > > > Hi, > > Whats the difference in coord generation (in practice) between TexGenNode > and Group with TexGen attribute. Suppose I have the same subgraph attached > to either such TexGenNode or such Group with TexGen. In both cases TexGens > are eye linear and use the same texture stage. > > I expected them to produce the same tex coords but results different. So I > am bit puzzled. What did I miss ? > > Cheers, > Wojtek Lewandowski > _______________________________________________ > 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
