Real-Time Physics Simulation Forum

Static planar heightfields are fairly popular in collision detection. However you can extend this idea for convex-convex collision detection/penetration depth using cylindrical or spherical heightfields. Kind of the 2D version of signed distance maps. Signed distance maps require 2 representations, ...

When dealing with static geometry, artifacts can happen when sliding over borders between triangles. Do people have special code to mark interior edges? Convex decomposition? Special ways of keeping contact points persistent from one triangle to the next?

First of all, wish you all a happy new year. 2006 will be a very exciting year with the Playstation 3, Ageia PhysX and Havok GPU physics coming out. The updated version of Bullet has bounding volume hierarchies, with GPU in mind. It features stackless traversal. See this topic on gpgpu.org: http://w...

New bugfixes. Please check this win32 build: http://www.continuousphysics.com/ftp/pub/test/blender/blender241.zip 1. Ray sensor is broken 2. Force doesn't work. 4. Cannot use python function setPosition(), doesn't do anything 5. Using end object actuator will cause blender to close (on some rare oca...

Hi Jan, Thanks for the feedback. BulletOde is not very robust for large size-ratios. Partly this is due to the implementation, and partly due to the nature of the sub-distance algorithm (innerloop replacement of Johnson within GJK). There are are couple of options to check out, and I will have a loo...

I fixed a couple of things in Bullet-Blender integration. Hooked up the 'formfactor' (an inertia tweak), friction, restitution, and some scaling related things. However, the rounded ramp really doesn't have a proper slope in the corner. Please try to fix the artwork, it should roll much better. Try ...

fobsta, I had a brief look at the demo and it looks great fun! One thing, scaling is not really supported properly, so you better apply the 'size', especially for dynamic objects. Can you try this Blender 2.41 build, it has a few small fixes, like add/remove object support, hopefully more stable and...

A bounding volume hierarchy has been added to cvs today and the bullet source archive has been updated. Please let me know if this works for you. The vc7/vc8 projectfiles have been updated, if you use vc6 please add a few files from the Bullet/CollisionShapes folder: BvhTriangleMeshShape.cpp Optimiz...

I've tested various parameters. You should first switch from Bullet physics to Sumo physics in the World parameters tab. Nope. Sumo is obsolete, and will be removed in one of the future releases once Bullet has been hooked up properly. I will have a look at the scene and fix it, together with some ...

3) So after the many-object (broadphase + hierarchies) the problem reduces to either 1 static triangle versus dynamic bounding primitive or dynamic bounding versus dynamic bounding? Dynamic triangle-triangle is the final test. I'm surprised that dynamic triangle-triangle is the final test. Real-tim...

Initially I worked with spheres, but that lasted only until I came upon Dave Eberly's Wild Magic code. I've debugged, optimized, and extended some of the collision detection code. I've provided it all to Eberly and some has been added to the main code base. The portions I use handle triangle meshes...

... and what would be considered better results than collision response at the first time of impact? The main unknown of their approach is how they 'estimate' the first time of impact, rathern then what to do with this time. I guess they either subdivide the timestep until there are no large 'gaps'...

Have you already looked at the docs in this file: http://uk.geocities.com/olivier_rebellion/Polycolly.zip It has tutorial for the time of impact and contact generation in the 2D case. You will get more response on such questions in the gamedev.net forum: http://www.gamedev.net/community/forums/forum...

You can download this paper from MIT here: http://www.ai.mit.edu/research/publications/browse/0800browse.shtml The approach in this paper is a Parameterized Sweep. If you are interested in calculating the time of impact, you can read some papers by Stephane Redon here: http://i3d.inrialpes.fr/~redon...

Using the Blender armatures UI is an interesting idea. At the moment armatures are just using IK, isn't it? We could add bullet physics contraints (like point to point) to keep the armature together, to allow for ragdolls. Is that what you meant? At the moment the armatures have been redone inside B...