3D Tools and Effects
Applying Masks
To apply a mask to a 3D object, use the Mask section in the Inspector. The effect has exactly the same set of properties as the 2D mask.
The program applies a mask to your object after applying other effects such as transformation or 3D rotation. This means that if you distort an object, the mask will not be affected.
In order to achieve interesting effects, you can combine a masked layer with another layer in the background and have the gaps filled with some color.