"I don't get modes 2 and 3. Mode 2 seems to lock it to the local mesh coordinates, in which case, what's the point of cube mapping at all? You might just as well apply UV coordinates and use an ordinary texture."
No, mode 2 does not lock it to the mesh. It projects it onto the mesh.
If the mesh was rotating you would see that the top of the cubemap always maps to whichever part of the model points towards the positive Y axis of the world.
I didn't rotate the teapot though because it would be very hard to tell that this is what is going on. When the teapot is rotating rather than the camera, it's hard to tell the difference between mode 1 and 2.
"Mode 3 doesn't show up here at all. I just a blank entity that's semi-transparent. I tried changing the texture res, but it doesn't show on the model, so I'm pretty sure there's nothing being mapped to the model in mode 3."
"A blank entity that's semi transparent". That sounds to me like something IS showing up.
The effect in this mode is not what you might expect so you might think you're not seeing it right when you are.
Hit F8 and post the screenshot here so we can see what you're seeing.
No, mode 2 does not lock it to the mesh. It projects it onto the mesh.
If the mesh was rotating you would see that the top of the cubemap always maps to whichever part of the model points towards the positive Y axis of the world.
I didn't rotate the teapot though because it would be very hard to tell that this is what is going on. When the teapot is rotating rather than the camera, it's hard to tell the difference between mode 1 and 2.
"Mode 3 doesn't show up here at all. I just a blank entity that's semi-transparent. I tried changing the texture res, but it doesn't show on the model, so I'm pretty sure there's nothing being mapped to the model in mode 3."
"A blank entity that's semi transparent". That sounds to me like something IS showing up.
The effect in this mode is not what you might expect so you might think you're not seeing it right when you are.
Hit F8 and post the screenshot here so we can see what you're seeing.