Raycaster: use a root node for each mesh.
Raycaster: use a root node for each mesh.

Each object now has its own root node.
Each node now initialises its children, to be directly aware of their locations.


Former-commit-id: 55514cce7214ef9b6e5e3a81610c541244ee894e
kosua20/GL_Template,kosua20/GL_Template