Ian, I don't know about the individual memory reqs of Transform3D and TransformGroup, but I do know from my own projects by experimenting with SharedGroups, that the SharedGroup approach is the way to go with clear advantanges in the construction time of the scene, the memory footprint and the performance of the final scene.
In one of my previous projects I built a J3D molecular viewer where I can turn on the use of SharedGroups for atoms (Primitive=Sphere) and bonds (Primitive=Cylinder) explicitly. When loading a 1500 atom molecule, the whole app requires about 30MByte of memory with SharedGroups, but without I quickly run out of the 128MByte memory I give to the JVM. For a smaller molecule of say 100 atoms, where I can get thru with doing it both ways, I find the construction time with SharedGroups about half compared to when using no SharedGroups. Also, the scene is much more responsive to mouse operations when using SharedGroups. I found, however, that SharedGroups have their limitations, too. If you need to be able to pick an individual object in the scene and do some special rendering (e.g. change its appearance) on it depending on its picked state, it must not be in a SharedGroup, as all items in the group share the same appearance. H. =========================================================================== To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff JAVA3D-INTEREST". For general help, send email to [EMAIL PROTECTED] and include in the body of the message "help".
