Search found 8 matches

by mpm
Sun May 08, 2022 7:26 am
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: 10 Minute Physics
Replies: 1
Views: 385

Re: 10 Minute Physics

Thanks for posting this! I too have been keeping a watch on this and I really appreciate the folks from Nvidia for their openess and contribution about their key methods - now with even a hands on approach. It's a shame the number of view is just in the thousands and that these forums have kind of d...
by mpm
Sun Jul 25, 2021 8:51 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: Newton Dynamics paper
Replies: 0
Views: 4572

Newton Dynamics paper

Did the Newton developers release any paper that describes their approach? Looking at GitHub and the wiki there isn't really much information available.
by mpm
Wed Dec 18, 2019 9:11 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: nVidia's new Temporal Gauss-Seidel (TGS) solver in PhysX 4
Replies: 1
Views: 7462

nVidia's new Temporal Gauss-Seidel (TGS) solver in PhysX 4

So Nvidia introduced a PGS derivative called TGS with much improved convergence rate over their old PGS solver and adding support for much larger mass ratios. Videos look impressive, esp. for difficult constraint types like prismatic, and so far some testing (IIRC our very own Erwin Coumans found so...
by mpm
Sat Dec 29, 2018 4:30 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Correct Contact Manifold
Replies: 3
Views: 10949

Re: Correct Contact Manifold

The final simplex that GJK/EPA terminates with has a point, an edge or a triangle that faces the origin. If it's a point, then the witness points on the involved shapes maps directly onto each of their individual support points. Contrary, if it is an edge or a face, then you will first have to calcu...
by mpm
Sat Dec 29, 2018 4:24 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Question about PBD stabilization
Replies: 1
Views: 6192

Re: Question about PBD stabilization

I get a feeling that you are referring to Nvidia's unified particle physics paper, but I'll link to it anyways: http://mmacklin.com/uppfrta_preprint.pdf Section 4.4 discusses the issue in PBD you bring up using a small number of pre-stabilization iterations, specifically how this problem becomes wor...
by mpm
Wed Aug 30, 2017 5:01 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: Throwback: Karma physics engine user guide
Replies: 0
Views: 7280

Throwback: Karma physics engine user guide

This might not be popular, but while I have not seen much discussion on these forums about the old Karma engine I think it still deserves a special mention. MathEngine's user guide for Karma gives a thorough, although dated, introduction to dynamical simulation for entertainment purposes. You can st...
by mpm
Tue Apr 18, 2017 7:00 pm
Forum: General Bullet Physics Support and Feedback
Topic: How to stop a body from losing velocity/bounce so quickly?
Replies: 4
Views: 4226

Re: How to stop a body from losing velocity/bounce so quickl

From my own experience basing the bounce velocity on the previous frame's velocity makes the simulation much more stable for restitution How do you do this exactly? This sounds like a good solution. Apologies, forgot to emphasize that this is in my own physics engine and not in Bullet. It was done ...
by mpm
Mon Apr 17, 2017 12:46 pm
Forum: General Bullet Physics Support and Feedback
Topic: How to stop a body from losing velocity/bounce so quickly?
Replies: 4
Views: 4226

Re: How to stop a body from losing velocity/bounce so quickl

The combined restitution is .4 x .9 = .36, so within the second bounce, not accounting for linear damping, the energy is down to 13% (and by E=0.5mv^2 that is less than 2% of the original velocity) so you need to up the coefficient of restitution. Have you tried enabling continuous collision detecti...