Impossible Shelf 3D Optical Illusion

Could you set anything on a shelf like this which was made using only right angles?

See Another Random Optical Illusion

Explanation

This optical illusion uses the techniques of perspective angles and overlap. The shelf which holds the red and green balls is cut short. So is the face of that shelf. They should both extend to the right, beyond the end of the illusion. The perspective angles given to the ends make them look entirely different.

To add to the confusion, the blue and yellow balls are really suspended in mid air, but that makes no sense. Rather, we interpret them to be sitting on a shelf.