- G3D_LOCAL_SPACE, /* this being 0 makes a nice default arg. */
- G3D_WORLD_SPACE, /* ignore world matrix */
- G3D_VIEW_SPACE, /* ignore view matrix */
- G3D_CLIP_SPACE, /* ignore projection matrix */
- G3D_SCREEN_SPACE,/* 2D verts, don't divide by w */
- G3D_PIXEL_SPACE /* in pixel units, ignore viewport */