A Unified Analysis of Collision Penalty Energies - Codebase

Hello! This repository demonstrates the analysis of various collision penalties as described in the SCA 2023 paper A Unified Analysis of Collision-Penalty Energies, by Alvin Shi and Theodore Kim.

The simulator's basic structure is based off of HOBAK, from the SIGGRAPH 2022 Course Dynamic Deformables: Implementation and Production Practicalities (Now With Code!), by Theodore Kim and David Eberle.

Running The Simulation

Run one of make linux or make mac (depending on your system) to compile dependencies and run the hammock simulation in projects/simulateHammock. Controls (much like the HOBAK interface) are as follows:

• a will start and stop the animation.
• q will quit and write out a QuickTime movie of the animation. You need to have FFMPEG installed for the movie write to succeed. Note that JSON scene descriptions are not available.
• Q or Esc will quit without saving anything.

Matlab Verification

Matlab scripts for testing the energies described in the paper are located in Matlab_Verification. Running any of the Verify_[energy/length] notebooks will validate analytic expressions against numerical differences.

C++ Unit Tests

You can run unit tests for the C++ energy implementations like so:

cd projects/unitTests
make depend
make
cd ../../bin
./unitTests

We put various vertex-face/edge-edge collision frame/length/energy arrangements through a finite-differencing comparison for gradients and Hessians.

Collision Eigenanalysis

The files located in src/Collision contain C++ implementations of general energy eigenpairs and secondary term handling. Feel free to swap out different frames, 1D energies, and lengths to get different qualitative results by modifying/making your own setCollision()-like functions in src/Scenes/SIMULATION_SCENE.h.

FAQ

Where is include_top.mk?

It gets made when make linux or make mac are run!