Cloth simulation

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saggita
Posts: 13
Joined: Tue Apr 19, 2011 11:46 pm

Cloth simulation

Post by saggita »

I made a cloth simulation using c++. It uses implicit backward euler integration and continuous collision detection for cloth-object and cloth self-collision. Strain limiting was used to simulate inextensible cloth. BVH/AABB was implemented to avoid n^2 collision checking. Rendering was done in Maya using AnimOBJ(http://code.google.com/p/animobj) which is made by myself as well.

Below is a link to the short video.

http://www.youtube.com/watch?v=YVhD2d2wWHU

I am currently trying to implement global collision treatment methods based on papers below.
If you have some experience with global collision treatment, please share your idea with me. I implemented the second one (volume preserving impulses) and have some problem with convergence. I believe the matrix is not really definite and need to use GMRES. I am using conjugate gradient now.

Also the first paper is somehow confusing.

Thank you.
saggita
Posts: 13
Joined: Tue Apr 19, 2011 11:46 pm

Re: Cloth simulation

Post by saggita »

Since my previous posting, I've been developing my own simultaneous proximity and continuous collision handling method for cloth simulation. I tried a couple of approaches like ones linked above and was not satisfied much. Below is a link to my current approach in youtube.

http://youtu.be/6yKrcV16k6A

The idea is basically creating a big linear equation and solve it rather than treating individual collisions iteratively until it converges. It is kind of similar to LCP but I am using impulses and proximity information in position level rather than velocity level. The matrix of linear equation can be over-constrained and ill-conditioned due to the complexity and irregularity of collision distribution. I overcome the problem by using conditional regularization. This research is still on-going but I just want to share it.

Attaching a screenshot to show the stress test with more clothes.
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Cloth2D_Test 2013-06-26 22-09-16-09.jpg
Cloth2D_Test 2013-06-26 22-09-16-09.jpg (236.18 KiB) Viewed 8625 times
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