scene = viz.MainScene
If the parent is viz.WORLD or viz.SCREEN, then the argument represents the scene to add the object to.
If the parent is viz.ORTHO, then the argument represents the window to add the object to.
If the parent is a valid node3d object, then the argument is ignored.
A texture quad is a square polygon which is usually used to display textures. The default size is 1 x 1.