Search found 34 matches

by Etherton
Thu May 04, 2006 6:52 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Baraff's LCP solver with friction
Replies: 7
Views: 13846

Are there any specific reasons that you use Baraff's method now? It's considered to be obsolete by timestepping method. Instaneous method (the last paper we've seen is Baraff's) suffers from alot of problems, including non-existence solution, worst-case exponential,etc... Saying Baraff work obsolet...
by Etherton
Wed Apr 05, 2006 5:53 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Which LCP's solver have been used by popular physics engine?
Replies: 24
Views: 50127

Newton? Why settle for a run of the mill simple free engine, that is mediocre at best. Wouldn't it be better to break or figure out PhysX/Novodex or Havok? For example, he has stated in these boards that Newton DOES use LCP. Remember when reading "marketting" text, you must be very careful...
by Etherton
Fri Mar 31, 2006 9:17 pm
Forum: Physics authoring tools, serialization, standards and related topics
Topic: "ARB" moderated physics API, OpenPL, DirectPhysics
Replies: 16
Views: 32683

You seem passionate about this; if you are also qualified, then why don't you join us? I am not as ahead of the time as you are, so perhaps my qualifications are not sufficiently good. I am still stuck in philosophy ?first you have a problem then you find a solution?. I always thought that the usef...
by Etherton
Thu Mar 30, 2006 7:32 pm
Forum: Physics authoring tools, serialization, standards and related topics
Topic: "ARB" moderated physics API, OpenPL, DirectPhysics
Replies: 16
Views: 32683

My impression was that ?standards? like ODF and Collada were made to do that. Open GL had a very humble origin, it was a simple 2d graphics library made by IRIS. The design was so good that it became an industry standard not by design but by choice. Now OpenGL have the ?Architecture Revision Board?,...
by Etherton
Wed Mar 29, 2006 9:23 pm
Forum: Physics authoring tools, serialization, standards and related topics
Topic: "ARB" moderated physics API, OpenPL, DirectPhysics
Replies: 16
Views: 32683

These are some more standards too:
Collada, ODF, PAL, OPAL, and now openPL
These are the more popular but there are about a dozen more that don?t get mention.
Um very soon we will need a super standard to cover all the standards.
by Etherton
Sun Mar 19, 2006 10:28 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Which LCP's solver have been used by popular physics engine?
Replies: 24
Views: 50127

Again it is not a matter of agree or disagree. Unless you guys have seen the source code and can confirm the fact by releasing the code, which will be a very dishonest act, it is a speculation. I think you can say that Bullet and ODE are using that same iterative solver, and you think that other eng...
by Etherton
Sun Mar 19, 2006 5:25 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Which LCP's solver have been used by popular physics engine?
Replies: 24
Views: 50127

I think it is a little pretentious saying most popular and unpopular are using the same algorithm, how would you know that? You only presented vague slides from a presentation that does not say anything definitive one way or another. You seem to have made your mind on engine comparison, so I am curi...
by Etherton
Thu Feb 16, 2006 6:13 am
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: New physics engine in academia
Replies: 9
Views: 12780

Forgive my ignorance but I do not know what an NLP and NCP solver is. My impression was that the LCP condition for constrained dynamics comes from the formulation of the equation of unilateral constraints that lead to a Linear Complementary Problem. What kind of formulation leads to these NCP or NCP...
by Etherton
Wed Feb 15, 2006 8:00 pm
Forum: Physics authoring tools, serialization, standards and related topics
Topic: Will this be possible in future releases(2.42 perhaps)
Replies: 9
Views: 11344

I do not think I am ready for Collada just yet. I find too cumbersome. I am thinking a proprietary format that could only be use to exports and import scene for me engine, kind of Gmax. I was thinking of writing the editor myself but it is lot of works, so I thought I could take a short cut. Since m...
by Etherton
Wed Feb 15, 2006 6:43 pm
Forum: Physics authoring tools, serialization, standards and related topics
Topic: Will this be possible in future releases(2.42 perhaps)
Replies: 9
Views: 11344

Blender is GPL so you won't be able to distribute it with a gpl incompatible license. In other words, you can't integrate Novodex, Havok, Newton, Tokamak, because they are closed source and non-gpl. But you are allowed to do it all in-house, just don't distribute any binary/source. I see, I was loo...
by Etherton
Wed Feb 15, 2006 4:53 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: New physics engine in academia
Replies: 9
Views: 12780

It seem physics engines are dozen for dime now. Here is another one

http://www.ThePhysicsEngine.com

They both promise in the future they will be better than the others.
by Etherton
Tue Feb 14, 2006 3:31 pm
Forum: Physics authoring tools, serialization, standards and related topics
Topic: Will this be possible in future releases(2.42 perhaps)
Replies: 9
Views: 11344

Can blender support native pluggins?
It is possible to integrate other physics engines with blender?
Are they license limitations?
by Etherton
Tue Jan 03, 2006 11:23 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Projected Gauss Seidel patent and other physics patents
Replies: 19
Views: 32904

Wow this is outrageous and disgusting. Projected Guass Seidel is been used by mostly all real-time physics engines since they became a software commodity. I used to work with Math Engine before it when under and the last incarnation implemented the same method and it was called the Arthur Solver, re...
by Etherton
Mon Nov 28, 2005 12:05 am
Forum: General Bullet Physics Support and Feedback
Topic: Iterative Dynamics :: PGS solver
Replies: 11
Views: 17282

I also simulate ragdolls just fine at 30Hz and 5 iterations. My engine benefits from contact caching (which ODE lacks). But that's not the whole story. Try to use capsules for the limbs, this makes the collision smoother. For the mass use capsule inertia tensors, but scale it up. I use a factor of ...