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Burst Softbodies - Parallelised Shape-Matching

This is a commented implementation of the paper Meshless Deformations Based on Shape Matching in Unity, using the C# Job System and Burst compiler available in Unity 2018.1 onwards. It also uses GPU based indirect drawing, to speedily visualise points pulling from a texture. It can handle several hundred thousand particles in under 16ms (machine-dependent!).

Implementation

• I'm using a Position Based Dynamics integration scheme, kind of arbitrarily -- as a result the system's stiffness is iteration-dependent but generally quite friendly to deal with, and suffers from some inherent motion damping.
• Particles are processed in parallel using the job system. Additionally, steps of the algorithm requiring linear summations have been partially parallelised by splitting sums into batches.
• This implementation includes support for linear deformation, extending the range of possible motion (stretch and shear). Support for twisting and bending would require the quadratic extension, detailed in the original paper.
• I've only tested this in Unity 2018.2.0f1! I hope it works for you too!!

Misc notes

• I tried using IJobParallelForBatch to perform the center-of-mass and shape matrix summations, but couldn't quite get this working. Maybe you can?
• There's a little bit of drift occuring when performing the parallel center-of-mass summation which doesn't occur in the linear equivalent. I think this is due to floating point precision, but is maybe worth investigating.
• This project is under an MIT license, feel free to do whatever you like with it -- let me know if you make anything cool! x