- threading: adding btSequentialImpulseConstraintSolverMt - task scheduler: added parallelSum so that parallel solver can compute residuals - CommonRigidBodyMTBase: add slider for solver least squares residual and allow multithreading without needing OpenMP, TBB, or PPL - taskScheduler: don't wait for workers to sleep/signal at the end of each parallel block - parallel solver: convertContacts split into an allocContactConstraints and setupContactConstraints stage, the latter of which is done in parallel - parallel solver: rolling friction is now interleaved along with normal friction - parallel solver: batchified split impulse solving + some cleanup - parallel solver: sorting batches from largest to smallest - parallel solver: added parallel batch creation - parallel solver: added warmstartingWriteBackContacts func + other cleanup - task scheduler: truncate low bits to preserve determinism with parallelSum - parallel solver: reducing dynamic mem allocs and trying to parallelize more of the batch setup - parallel solver: parallelize updating constraint batch ids for merging - parallel solver: adding debug visualization - task scheduler: make TBB task scheduler parallelSum deterministic - parallel solver: split batch gen code into separate file; allow selection of batch gen method - task scheduler: add sleepWorkerThreadsHint() at end of simulation - parallel solver: added grain size per phase - task Scheduler: fix for strange threading issue; also no need for main thread to wait for workers to sleep - base constraint solver: break out joint setup into separate function for profiling/overriding - parallel solver: allow different batching method for contacts vs joints - base constraint solver: add convertJoint and convertBodies to make it possible to parallelize joint and body conversion - parallel solver: convert joints and bodies in parallel now - parallel solver: speed up batch creation with run-length encoding - parallel solver: batch gen: run-length expansion in parallel; collect constraint info in parallel - parallel solver: adding spatial grid batching method - parallel solver: enhancements to spatial grid batching - sequential solver: moving code for writing back into functions that derived classes can call - parallel solver: do write back of bodies and joints in parallel - parallel solver: removed all batching methods except for spatial grid (others were ineffective) - parallel solver: added 2D or 3D grid batching options; and a bit of cleanup - move btDefaultTaskScheduler into LinearMath project
Bullet Physics SDK
This is the official C++ source code repository of the Bullet Physics SDK: real-time collision detection and multi-physics simulation for VR, games, visual effects, robotics, machine learning etc.
New in Bullet 2.85: pybullet Python bindings, improved support for robotics and VR. Use pip install pybullet and see PyBullet Quickstart Guide.
The Bullet 2 API will stay default and up-to-date while slowly moving to a new API. The steps towards a new API is in a nutshell:
- The old Bullet2 demos are being merged into the examples/ExampleBrowser
- A new physics-engine agnostic C-API is created, see examples/SharedMemory/PhysicsClientC_API.h
- Python bindings in pybullet are on top of this C-API, see examples/pybullet
- A Virtual Reality sandbox using openvr for HTC Vive and Oculus Rift is available
- The OpenCL examples in the ExampleBrowser can be enabled using --enable_experimental_opencl
You can still use svn or svn externals using the github git repository: use svn co https://github.com/bulletphysics/bullet3/trunk
Requirements for Bullet 2
A C++ compiler for C++ 2003. The library is tested on Windows, Linux, Mac OSX, iOS, Android, but should likely work on any platform with C++ compiler. Some optional demos require OpenGL 2 or OpenGL 3, there are some non-graphical demos and unit tests too.
Contributors and Coding Style information
https://docs.google.com/document/d/1u9vyzPtrVoVhYqQOGNWUgjRbfwfCdIts_NzmvgiJ144/edit
Requirements for experimental OpenCL GPGPU support
The entire collision detection and rigid body dynamics can be executed on the GPU.
A high-end desktop GPU, such as an AMD Radeon 7970 or NVIDIA GTX 680 or better. We succesfully tested the software under Windows, Linux and Mac OSX. The software currently doesn't work on OpenCL CPU devices. It might run on a laptop GPU but performance will not likely be very good. Note that often an OpenCL drivers fails to compile a kernel. Some unit tests exist to track down the issue, but more work is required to cover all OpenCL kernels.
License
All source code files are licensed under the permissive zlib license (http://opensource.org/licenses/Zlib) unless marked differently in a particular folder/file.
Build instructions for Bullet using premake. You can also use cmake instead.
Windows
Click on build_visual_studio_vr_pybullet_double.bat and open build3/vs2010/0MySolution.sln When asked, convert the projects to a newer version of Visual Studio. If you installed Python in the C:\ root directory, the batch file should find it automatically. Otherwise, edit this batch file to choose where Python include/lib directories are located.
Windows Virtual Reality sandbox for HTC Vive and Oculus Rift
Build and run the App_SharedMemoryPhysics_VR project, preferably in Release/optimized build. You can connect from Python pybullet to the sandbox using:
import pybullet as p
p.connect(p.SHARED_MEMORY) #or (p.TCP, "localhost", 6667) or (p.UDP, "192.168.86.10",1234)
Linux and Mac OSX gnu make
Make sure cmake is installed (sudo apt-get install cmake, brew install cmake, or https://cmake.org)
In a terminal type:
./build_cmake_pybullet_double.sh
This script will invoke cmake and build in the build_cmake directory. You can find pybullet in Bullet/examples/pybullet. The BulletExampleBrowser binary will be in Bullet/examples/ExampleBrowser.
You can also build Bullet using premake. There are premake executables in the build3 folder. Depending on your system (Linux 32bit, 64bit or Mac OSX) use one of the following lines Using premake:
cd build3
./premake4_linux gmake --double
./premake4_linux64 gmake --double
./premake4_osx gmake --double --enable_pybullet
Then
cd gmake
make
Note that on Linux, you need to use cmake to build pybullet, since the compiler has issues of mixing shared and static libraries.
Mac OSX Xcode
Click on build3/xcode4.command or in a terminal window execute
./premake_osx xcode4
Usage
The App_ExampleBrowser executables will be located in the bin folder. You can just run it though a terminal/command prompt, or by clicking it.
[--start_demo_name="Demo Name"] Start with a selected demo
[--mp4=moviename.mp4] Create a mp4 movie of the window, requires ffmpeg installed
[--mouse_move_multiplier=0.400000] Set the mouse move sensitivity
[--mouse_wheel_multiplier=0.01] Set the mouse wheel sensitivity
[--background_color_red= 0.9] Set the red component for background color. Same for green and blue
[--fixed_timestep= 0.0] Use either a real-time delta time (0.0) or a fixed step size (0.016666)
You can use mouse picking to grab objects. When holding the ALT or CONTROL key, you have Maya style camera mouse controls. Press F1 to create a series of screenshots. Hit ESCAPE to exit the demo app.
Check out the docs folder and the Bullet physics forums for further information.
