Search found 4221 matches

by Erwin Coumans
Mon Sep 12, 2005 6:45 am
Forum: Physics authoring tools, serialization, standards and related topics
Topic: Gameblender seemably slower than other demos?
Replies: 3
Views: 7137

There are issues in gameblender indeed, can't tell what it is yet, I havent been involved in its development for the last few years.
by Erwin Coumans
Thu Sep 08, 2005 5:56 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: GPGPU General-Purpose Computation Using Graphics Hardware
Replies: 0
Views: 5271

GPGPU General-Purpose Computation Using Graphics Hardware

http://www.gpgpu.org/

Using the GPU for things other then 3D graphics. Physics for example :)

Raycasting, Collision Detection and Rigidbody simulation can potentially
get some nice speedup using graphics hardware.

See also: http://graphics.stanford.edu/projects/b ... index.html
by Erwin Coumans
Thu Sep 08, 2005 11:53 am
Forum: General Bullet Physics Support and Feedback
Topic: ODE sample integration
Replies: 2
Views: 6944

Hi, very well spotted :) - regarding objects of large size differences, the penetration depth solver is indeed very experimental. However even commercial physics engines have difficulties with large scale ratios. It is recommended to add a PlaneShape to the primitives. This will then project the oth...
by Erwin Coumans
Wed Sep 07, 2005 12:23 pm
Forum: General Bullet Physics Support and Feedback
Topic: Bullet Convex Collision integrated in a ODE demo
Replies: 2
Views: 6356

Bullet Convex Collision integrated in a ODE demo

Here is a new demo, with updated convex collision primitives using Bullet GJK in the ODE (http://www.ode.org) framework. It is a proof of concept to show that the Bullet collision code can be ported to other physics engines too. Press 1,2,3 or 4 in the windows demo 'bulletgjk_ode.zip', for cylinders...
by Erwin Coumans
Tue Sep 06, 2005 3:53 pm
Forum: General Bullet Physics Support and Feedback
Topic: Bullet GJK for ODE preview
Replies: 1
Views: 6408

Updated files

NOTICE: The initial demo binary had some problem, it lacked a manifest file called 'Microsoft.VC80.CRT.manifest'... So it didn't execute on most computers. See explanation below. This is fixed in the latest upload. "This application has failed to start because the application configuration is i...
by Erwin Coumans
Mon Sep 05, 2005 11:52 pm
Forum: General Bullet Physics Support and Feedback
Topic: Bullet GJK for ODE preview
Replies: 1
Views: 6408

Bullet GJK for ODE preview

First preview of Bullet GJK Convex Collision Detection integrated with Open Dynamics Engine (ODE). Press l for a bullet gjk cylinder, f for a bullet gjk box, b, s and c for ode colliders. Other convex primitives like cone, convex mesh are a matter of adding graphics drawstuff for ODE. Disclaimer: it...
by Erwin Coumans
Mon Sep 05, 2005 9:05 am
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Non-Determinism in Multiplatform Networking Physics
Replies: 2
Views: 7711

Non-Determinism in Multiplatform Networking Physics

Due to lots of reasons a physics simulation can be non-deterministic, or in other words the simulation results will be different with the same starting conditions (*). In multiplatform networked games like massive multiplayer online games (MMO) this has to be dealt with. 0) How do you deal with mult...
by Erwin Coumans
Fri Sep 02, 2005 2:53 pm
Forum: General Bullet Physics Support and Feedback
Topic: Bullet Physics Forum Announcement
Replies: 0
Views: 5860

Bullet Physics Forum Announcement

Hi, The Bullet Continuous Physics Forum has been upgraded to a new server and also a mailing list feature is added. At any time you can visit the Forum Subscription to add / remove subscriptions: http://207.234.235.180/Bullet/phpBB2/m2f_usercp.php Those announcements are very infrequent (about once ...
by Erwin Coumans
Fri Sep 02, 2005 2:35 pm
Forum: Links, Papers, Libraries, Demos, Movies, Comparisons
Topic: Ageia acquires Meqon
Replies: 1
Views: 6417

Ageia acquires Meqon

Ageia, the hardware-based physics middleware company just acquired Meqon: http://news.teamxbox.com/xbox/9146/AGEIA-Acquires-Meqon-Research-AB/ http://ve3d.ign.com/articles/647/647354p1.html http://biz.yahoo.com/prnews/050901/sfth012.html?.v=22 http://www.gamasutra.com/php-bin/news_index.php?story=63...
by Erwin Coumans
Sun Aug 21, 2005 8:36 am
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Bullet's Voronoi Simplex Solver
Replies: 46
Views: 127804

Maybe for you it is, do you know that before Gino and Ericson re-wrote JGK algorithm? I follow Gino's work since around 1995, when we met at Eindhoven University, so I know he rewote it in a very good way. There are over a dozen packages (physics engines and stand alone collision systems) that are ...
by Erwin Coumans
Sat Aug 20, 2005 3:25 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Bullet's Voronoi Simplex Solver
Replies: 46
Views: 127804

If in these multithreaded environment things are so unpredictable what make you think your solutions are superior? On a Playstation 3 it is fairly well predictable, each SPU has its own local storage. I don't think filling this with cached data between frames helps. Between the gjk iterations its b...
by Erwin Coumans
Fri Aug 19, 2005 6:08 pm
Forum: Physics authoring tools, serialization, standards and related topics
Topic: New Bullet Gameblender build, 17 August 2005
Replies: 1
Views: 4572

New Bullet Gameblender build, 17 August 2005

A new build of Blender 3.38 with bullet rigidbody dynamics. +Hooked up Bullet raycasting to raycast sensor +Mouse over sensor works, including mouse over all (see jenga7) +Additional python methods in module PhysicsConstaints +Uses Bullet constraint solver by default (not ode quickstep) http://www.c...
by Erwin Coumans
Sun Aug 14, 2005 8:03 pm
Forum: General Bullet Physics Support and Feedback
Topic: Bullet and ODE
Replies: 5
Views: 10963

All I need is a way to get contact points from bullet. In that case, it is probably best to just use the collision detection, which is located in the /Bullet/Bullet folder. You don't need any of the dynamics or integration files (ConvexConvexCollisionAlgorithm). All you need it calling gjk, and pas...
by Erwin Coumans
Sun Aug 14, 2005 7:46 pm
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Bullet's Voronoi Simplex Solver
Replies: 46
Views: 127804

Then the barycentric coordinates are: (1-alpha, alpha) right? Is that correct? And what about the tetrahedron case? All correct. GJK needs separation in order to work. If the point is outside the tetrahedron, it is only closest to 1 triangle. If the point (origin) is inside the tetrahedron, a 'full...