Real-Time Physics Simulation Forum

But if you can come up with a constraint for three or more bodies, will SI still be able to iterate to a solution? If so, it's by far the most versatile and furthermore the easiest method to understand. Why would I say that? By accumulating the results of the iteration in the actual bodies' velocit...

Yeah . . . now I agree SI is the best method for games =) . . . I hate LCPs =P. How high of a vertical stack of boxes have you seen in real life? =D Well, well . . . SI is the way to go . . . its time to read lots of things =). Thanks for the help guys and, could any of you please point me a nice S...

I'm very frustrated : ( . . . it is unrealistic and inaccurate and have lots of problems that I could see in some simulations in Box2D, and it also need some workarounds to make things look a bit better. What I wanna know now is what method do the developers of games like Need For Speed Underground...

John, Thanks for the info. I'm still not sure how your algorithm is an improvement in the inelastic case. Perhaps you could try running this test: - 4 1m^3 boxes in a vertical stack - time step 1/30 - gravity 9.8 m/s^2 - friction 0.3, restitution 0.0 - no damping or sleeping - small vertical offset...

Hey Dirk, Yes, you must adjust the old position to update the velocity (see setTotalKineticEnergy () ). One of the comments regarding Jacobsen's tetrahedral rigid body idea is that it's hard to model controllable restitution. Thinking about just a particle system modeling a tetrahedron, when you pro...

John, I'm curious about your algorithm. Here are a few questions: 1) What is the particle model used for (just for correcting KE)? How do you compute contact points (RB or particle)? How do you integrate velocities (RB or particle)? How do you handle overlap resolution? 2) What does it mean to corr...

I found that if I changed velocity for position resolution, I could eliminate the need for iteration of resting contacts , stacks, etc., and also eliminate springiness/sponginess. The trick is to make sure that the change in velocity preserves total kinetic energy. Moving objects without correcting ...

Regarding section 7 of the paper, Future Work and rigid bodies: [snip] What I like about this method is it's based on constrained particle physics as opposed to optimization methods, which IMO looks much more realistic, and so far runs fast (have not spent any time optimizing the final system yet)....

Regarding section 7 of the paper, Future Work and rigid bodies: 1. Load track Colline Verdi II in my demo here: http://www.brightland.com/ac/ 2. Run into/shoot the box stacks. The rigid bodies are implemented using the methods described here: http://www.brightland.com/Physics/index.htm In simple ter...

High-quality h.264 video showing networked physics; 300ms ping, high speed driving and physical interaction, lag free:
http://files.filefront.com/ACR_300msmov ... einfo.html

Hi John, This realtime-tuning looks really great, I will check it out again. I'm also interested in your patch-collision detection. Are they bezier-patches? It would be great to extend COLLADA physics with such primitives. Do you have description of your curve/patch data? There is support in Bullet...

Adjust all major suspension, tire, engine, mass, and aerodynamic settings in real-time, interactively (including during online network play): http://www.brightland.com/ac/ (Beta 1.04) http://www.brightland.com/ac/AC_IS800_small.jpg http://www.brightland.com/ac/AC_IS800.jpg What?s New in Version 1.04...

Very nice demo John! Can you explain the rigid body physics (verlet particles?) and collision resolving methods to get stacking working in further detail? I've tinkered with verlet particle rigid bodies a while back, but I could never get stable stacking without lots of iterations. thanks Steve. Th...

Amazing Curves Racing: Networked Object Stacking http://www.brightland.com/ac/AC_Networked_Physics.jpg Also included are single pendulums, a triple pendulum (3 RB's linked in a chain), a triggered, canned-animation 'smasher', and a two-constraint jump/seesaw. Everything is networked, and should beh...

Hi Stan- looks good, fast and stable. Comments: Dean Macri @ Intel released an implicit cloth demo; I could not find the page/source on Intel's site (was not as fast/stable as your example). While searching for Dean's paper/demo, I found this link, with source: http://www.people.fas.harvard.edu/~hch...