Comments on: Game Physics

By: Glenn Fiedler

Glenn Fiedler — Fri, 04 Feb 2011 02:52:04 +0000

unfortunately, no. just articles on physics and networking. try wolfgang engel’s shader X series

By: Lost chuck

Lost chuck — Thu, 03 Feb 2011 20:18:10 +0000

Hey glen!
Thanks for these wonderful articles they have helped me so much!
I was wondering If you had written any articles about loading/rendering 3d models, or if you know of any good books about this as I haven’t found any that seem to be good,
thanks!

By: trackplay

trackplay — Tue, 25 Jan 2011 06:24:37 +0000

Wanted to thank you for these wonderful tutorials, A mind is a powerful tool, knowledge is power!

By: CodeCriminal

CodeCriminal — Sat, 15 May 2010 15:33:33 +0000

Ill second that – favourited!

By: Glenn Fiedler

Glenn Fiedler — Thu, 12 Nov 2009 23:53:22 +0000

it is generally necessary to renormalize the quaternion after you integrate it, provided that it is a certain distance from length 1.0, this may help.

By: dynamically challenged

dynamically challenged — Thu, 12 Nov 2009 23:50:18 +0000

I’m trying to simulate simple drifting of an object in a water flow. So, I start with a stationary object and expect it to speed up and reach steady state at the same speed as the current. It seems to do this but after reaching steady state, an oscillation develops that eventually diverges. I noticed that after a couple uses of coordinate transformations using quaternions, some of the x,y forces bleed into the z axis (which is a no-no for my 3dof sim). Do I need to normalize occasionally or take some action to prevent angular momentum from being developed somehow? The cube demo seems to have an angular velocity damping term added to prevent this from being a problem.. is it necessary because of precision issues with the implementation? Thanks for the discussion.

By: Glenn Fiedler

Glenn Fiedler — Thu, 12 Nov 2009 01:55:51 +0000

I really cannot comment without knowing more details about your simulation, what exactly are you trying to do?

By: dynamically challenged

dynamically challenged — Thu, 12 Nov 2009 01:03:07 +0000

Thanks for being so generous with the source code AND dynamics simulation explanations. I’ve tried using your example code to model a real dynamic system and run into the dreaded divergence ‘explosion’. Even though the dynamics are ‘low’ and the 100hz timestep should be plenty small enough (I think), it’s not easy sorting out the cause.. Any suggestions for diagnosing this general type of problem? Is there a general series of diagnostic steps that you’d recommend for resolving divergence? (I started by cutting the timestep down by a factor of 10 but it just pushed the divergence further out in time). Since everything is done as a float is there a potential for things to become denormalized/inconsistent that requires frequent action?

By: Glenn Fiedler

Glenn Fiedler — Thu, 15 Oct 2009 04:04:42 +0000

it is fixed, thank you!

By: scragar

scragar — Thu, 15 Oct 2009 00:51:50 +0000

On the spring physics page there’s a link tag around the text “next article” but it’s not linked to anything.