Re: [osg-users] transforming normals
Thanks, I will try it as soon as possible -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=8879#8879 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] transforming normals
Hi, I'm writing a simple nodevisitor to compute the lightmap of a given node. This nodevisitor treats transforms and geodes specially, so that each vertex in the geometry is multiplied with the most recent transform matrix in order to obtain world coordinates. So far the above code works well except that i don't know how to transform the normals. Can I obtain the normal matrix directly from the transformation matrix, if so how? Thank you, Can -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=8857#8857 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] transforming normals
Paul Melis wrote: Can Hosgor wrote: I'm writing a simple nodevisitor to compute the lightmap of a given node. This nodevisitor treats transforms and geodes specially, so that each vertex in the geometry is multiplied with the most recent transform matrix in order to obtain world coordinates. So far the above code works well except that i don't know how to transform the normals. Can I obtain the normal matrix directly from the transformation matrix, if so how? If M is your transformation matrix then (M^-1)^T transforms your normals (that's the transposed inverse of M). You might have to rescale your normals so they become unit length again, after using the above matrix Paul ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] transforming normals
Can Hosgor wrote: I'm writing a simple nodevisitor to compute the lightmap of a given node. This nodevisitor treats transforms and geodes specially, so that each vertex in the geometry is multiplied with the most recent transform matrix in order to obtain world coordinates. So far the above code works well except that i don't know how to transform the normals. Can I obtain the normal matrix directly from the transformation matrix, if so how? If M is your transformation matrix then (M^-1)^T transforms your normals (that's the transposed inverse of M). Paul ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
