Search found 2949 matches

by Erin Catto
Tue Mar 29, 2016 1:09 pm
Forum: News
Topic: Looking for Moderators
Replies: 0
Views: 2494

Looking for Moderators

Hi All, I'm looking for one or two people to help moderate this forum. Moderator duties are pretty simple: - Ban spammers and delete their posts - Keep me informed of any forum issues Ideally a moderator is also a frequent poster on these forums. Please send me a PM if you are interested. Thanks! Erin
by Erin Catto
Sun Jul 12, 2015 9:25 pm
Forum: General Discussion
Topic: Position projection
Replies: 3
Views: 1136

Re: Position projection

The position projection algorithm can be called Nonlinear Gauss-Seidel. It is inspired by position based dynamics. In particular I was inspired by Thomas Jakobsen's paper Advanced Character Physics. Matthias Müller-Fischer also wrote a nice paper about position based dynamics. The Box2D position pro...
by Erin Catto
Sat Apr 05, 2014 10:49 am
Forum: General Discussion
Topic: LCP and Constraint Solver
Replies: 1
Views: 1284

Re: LCP and Constraint Solver

An LCP in game physics is the mathematical equation governing a rigid body subject to inequality constraints, like contact. Constraint solvers are designed to solve LCPs.
by Erin Catto
Fri Mar 14, 2014 9:34 pm
Forum: General Discussion
Topic: It it a joke???? :)
Replies: 12
Views: 6825

Re: It it a joke???? :)

Fair points. I'll try to make the wording easier. I still stand by the results. We have far fewer spam bots since I added these questions, and it seems like the quality of posts has gone up. Also, keep in mind that anyone can read these forums. I feel like the privilege of posting should require som...
by Erin Catto
Fri Mar 14, 2014 9:22 pm
Forum: Bugs, Requests, and Feedback
Topic: Rendering issues with the new UI
Replies: 1
Views: 1903

Re: Rendering issues with the new UI

Wow, hmm I don't know what is wrong. I will be back on Box2D work in a couple weeks and finishing up the new render code. I'll look for anything suspicious.
by Erin Catto
Fri Mar 14, 2014 9:17 pm
Forum: General Discussion
Topic: Calling b2Body::SetLinearVelocity during contact callback
Replies: 2
Views: 1161

Re: Calling b2Body::SetLinearVelocity during contact callbac

I would not count on velocity modifications to stick. The solver might want to buffer the velocities in a separate array.
by Erin Catto
Thu Dec 12, 2013 11:09 am
Forum: Bugs, Requests, and Feedback
Topic: New Testbed idea request
Replies: 2
Views: 1322

Re: New Testbed idea request

There is such a test, it is called ApplyForce.
by Erin Catto
Sat Nov 30, 2013 12:50 am
Forum: Bugs, Requests, and Feedback
Topic: [Solved] Very slow with only 50 bodies
Replies: 7
Views: 3107

Re: [Solved] Very slow with only 50 bodies

Yeah, a NaN and Inf checker would be good.
by Erin Catto
Mon Nov 25, 2013 12:48 am
Forum: Bugs, Requests, and Feedback
Topic: Problem with tunneling between dynamic and static bodies
Replies: 13
Views: 6723

Re: Problem with tunneling between dynamic and static bodies

Assuming you have no bugs with your filters, you may just need to work on the mass distribution.

I give some tips in my ragdoll presentation on this page: https://code.google.com/p/box2d/downloads/list
by Erin Catto
Mon Nov 25, 2013 12:45 am
Forum: Build Issues
Topic: Compiling Box2d with TARGET_FLOAT32_IS_FIXED
Replies: 6
Views: 3348

Re: Compiling Box2d with TARGET_FLOAT32_IS_FIXED

You can get cross platform determinism with fixed point. You will need fixed point representations of all constants.

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