Search found 4173 matches

by Erwin Coumans
Wed Nov 14, 2018 11:23 pm
Forum: General Bullet Physics Support and Feedback
Topic: printStats()
Replies: 9
Views: 784

Re: printStats()

It looks like you got inspired by Dennis Gustafsson :-) ? https://twitter.com/tuxedolabs/status/1058381664001363968 >> I see that collision detection is also done in parallel. Nice! Yes apparently, it was a contribution, but the default broadphase/collision dispatcher in Bullet is single threaded. F...
by Erwin Coumans
Wed Nov 14, 2018 8:04 pm
Forum: General Bullet Physics Support and Feedback
Topic: printStats()
Replies: 9
Views: 784

Re: printStats()

Ignore printStats, it is not used. >> how many were eliminated by broadphase? If you want to know how many pairs there are, use btOverlappingPairCache::getNumOverlappingPairs Without a broadphase, you would check (n^2)/2, so you can compute the difference: (n^2)/2 - btOverlappingPairCache::getNumOve...
by Erwin Coumans
Tue Nov 06, 2018 5:07 am
Forum: PyBullet Support and Feedback
Topic: How to continue training a model with train_ppo ?
Replies: 1
Views: 437

Re: How to continue training a model with train_ppo ?

If you want to resume a previously started run, add the --timestamp=<time> flag to the last command and provide the timestamp in the directory name of your run. See also the more new version of PPO for more info on the --timestamp option. https://github.com/google-research/batch-ppo (the new version...
by Erwin Coumans
Tue Nov 06, 2018 4:59 am
Forum: PyBullet Support and Feedback
Topic: Reset gym environment with an observation
Replies: 1
Views: 353

Re: Reset gym environment with an observation

You will have to manually reset the state for all objects. See resetJointState and resetBasePositionAndOrientation, resetBaseVelocity in the PyBullet Quickstart Guide.
by Erwin Coumans
Tue Nov 06, 2018 4:57 am
Forum: PyBullet Support and Feedback
Topic: Why bullet proposes value to clamp number of substeps?
Replies: 1
Views: 279

Re: Why bullet proposes value to clamp number of substeps?

Clamping is important in real-time simulations, otherwise you get a feedback loop of slower and slower (grinding to a halt) if the time it takes to simulate is slower then the real-time clock. dt = clock.deltaTime(); stepSimulation(dt);//if this takes longer than dt, then the next iteration, the dt ...
by Erwin Coumans
Tue Nov 06, 2018 4:53 am
Forum: PyBullet Support and Feedback
Topic: Joint_spherical
Replies: 1
Views: 294

Re: Joint_spherical

The spherical joint is not exposed yet in PyBullet, we haven't had a robot using them. Also we don't have a motor for the spherical joint yet.

If we would expose the spherical joint, how would you actuate it?
by Erwin Coumans
Fri Nov 02, 2018 3:48 pm
Forum: General Bullet Physics Support and Feedback
Topic: Dramatic slow down when using SAT convex.
Replies: 5
Views: 482

Re: Dramatic slow down when using SAT convex.

>> Any idea why the fragments dance around like that? Perhaps the vertices are not centered around the origin? The center of mass needs to be at [0,0,0]. There is a similar demo in the example browser under Experiments/VoronoiFracture. (note that that demo has a small issue, after removing the const...
by Erwin Coumans
Fri Nov 02, 2018 3:33 pm
Forum: General Bullet Physics Support and Feedback
Topic: Spatial query of the world
Replies: 4
Views: 445

Re: Spatial query of the world

What type is TestCallback exactly? You should be able to override its 'needsCollision' virtual method.
by Erwin Coumans
Thu Nov 01, 2018 1:24 pm
Forum: General Bullet Physics Support and Feedback
Topic: Spatial query of the world
Replies: 4
Views: 445

Re: Spatial query of the world

Fastest is broadphase->aabbTest(), but based on aabb bounding volumes of objects.

Precise is collisionWorld->contactTest(). If you use a sphere (btSphereShape), it will be similar to the OpenDE test.

The query btCollisionObject in contactTest isn't part of the world.
by Erwin Coumans
Thu Nov 01, 2018 1:09 pm
Forum: General Bullet Physics Support and Feedback
Topic: Dramatic slow down when using SAT convex.
Replies: 5
Views: 482

Re: Dramatic slow down when using SAT convex.

Our SAT is not used by default and not well optimized. The default settings using GJK+EPA+ incremental persistent contact manifold should work really well, especially at 240hz. We accumulate up to 4 points, so there won't be single contacts for long. >> When not using SAT, I also see a slow down, sl...
by Erwin Coumans
Sun Oct 28, 2018 1:56 am
Forum: General Bullet Physics Support and Feedback
Topic: multibody m_appliedImpulse zero
Replies: 2
Views: 354

Re: multibody m_appliedImpulse zero

The applied impulse should be available in the post-tick callback, if you enable if SOLVER_USE_WARMSTARTING in the solver info.

In PyBullet that is how we provide the contact normal and lateral friction forces and they are non-zero.
by Erwin Coumans
Wed Oct 17, 2018 2:09 am
Forum: PyBullet Support and Feedback
Topic: pip install failure
Replies: 3
Views: 552

Re: pip install failure

It should be fixed now. Try using version 2.3.2 or later

pip install --no-cache-dir pybullet --user

Thanks for the report!
by Erwin Coumans
Mon Oct 15, 2018 11:04 pm
Forum: PyBullet Support and Feedback
Topic: How to Control Camera view of the GUI
Replies: 3
Views: 992

Re: How to Control Camera view of the GUI

Use the <CTRL> or <ALT> key in combination with mouse buttons+dragging the mouse.
Also you can use touch pad sliding to zoom in/out.
by Erwin Coumans
Mon Oct 15, 2018 11:03 pm
Forum: PyBullet Support and Feedback
Topic: Defining a Kinematic Object
Replies: 2
Views: 497

Re: Defining a Kinematic Object

It is recommended to use a fixed constraint and move the parent location of the fixed constraint. (Kinematic bodies are not supported in PyBullet) relativeChildPosition=[0,0,1] relativeChildOrientation=[0,0,0,1] hand_cid = p.createConstraint(hand,-1,-1,-1,p.JOINT_FIXED,[0,0,0],[0,0,0],relativeChildP...
by Erwin Coumans
Mon Oct 15, 2018 10:59 pm
Forum: PyBullet Support and Feedback
Topic: build failure for pybullet project in VS2017
Replies: 2
Views: 505

Re: build failure for pybullet project in VS2017

It is best to use 'pip install pybullet' to compile PyBullet. Edit the build file and remove the --enable_pybullet and re-create the project files. Compiling the Debug version of PyBullet is much mode work, since most Python distributions only ship with Release/optimized builds. Find/install some Py...