Shows how to display one entity with several render modes at once. The sidechains are displayed simple mode, whereas the backbone is displayed with smooth lines.
scene.RemoveAll()
ent=io.LoadPDB('data/sdh.pdb', restrict_chains='A')
go=gfx.Entity('SDH', ent)
go.SetRenderMode(gfx.SLINE)
sidechains=ent.Select('aname!=CA,C,N,O', mol.EXCLUSIVE_BONDS)
go.SetRenderMode(gfx.SIMPLE, sidechains)
scene.Add(go)
scene.CenterOn(go)
print 'Demo 1: loading and displaying a pdb file'