TUIO: Possible to erase existing preview pattern

[ukch]

To reproduce:

• Start TUIO and the game. Move fiducial 2 onto the game board so that the shape outline appears.
• Move fiducial 1 onto the board, making sure its shape entirely overlaps the original shape.
• Move fiducial 1 away from fiducial 2's position.

Expected: Fiducial 1's shape should still be there
Actual: Fiducial 1's shape has disappeared

[ukch]

I'm not sure if this is actually a real-world issue or just a TUIO-simulator issue, as in the real world you (presumably) can't have two objects in the same place as each other.