Hi, I have built 4 test cases of stacked cards. But when the friction is set to 0, they do not work as expected. Without any forces other than gravity, the cards slide or even rotate. Besides, when the gravity is set to 0, the simulations of these test cases do not terminate and keep looping on searching alpha value. Also, the 3D meshes used in my test cases are the same as the meshes used in the file 8_precision_card_shuffle.py, and I am running the latest source code.
I wonder if my test cases are incorrect, there is a bug in the source code, the friction model is not appropriate, or anything else is wrong?
In all my test cases, I set the shells (cards and tables) apart by their thickness plus a 1e-5 offset; so, they are barely touching each other. The 4 test cases are designed as:
- one_card_on_table.py: one card on a fixed table. Also, in this case, the simulation seems to be stuck in the loops of searching alpha value after frame 47.
- three_cards_on_table.py: 3-card stack on a fixed table.
- two_card_stack.py: 2-card stack, the bottom card is fixed.
- three_card_stack.py: 3-card stack, the bottom card is fixed.
The code of my test cases is in the attached zip file. They can be run using the same way to run the C-IPC examples.