Physics Simulation Forum

Bullet 2.74 is available for download:
http://code.google.com/p/bullet/downloads/list

New features:

• Constraint limits visualization, see Bullet/Demos/ConstraintDemo, thanks Roman Ponomarev
• All constraints can use the new generic SIMD optimized innerloop
• Improved Cone-twist and Generic 6DOF constraint, thanks Eddy Boxerman
• Buoyancy demos, see Bullet/Demos/HeightFieldFluidDemo, thanks John McCutchan
• Option for one-shot multiple-contact generation, use defaultCollisionConfiguration->setConvexConvexMultipointIterations()
• Improved ColladaConverter, with support for hinge and point 2 point constraint export
• Dynamica Maya plugin works for Maya 2009 now, thanks to Lawrence Chai from Disney Animation
• Some workaround to avoid crashes in character controller - dynamic object interaction
• Soft body self-collision, when using convex collision clusters
• deterministic btDbvtBroadphase, use broadphase->resetPool(dispatcher), and see DemoApplication::clientResetScene
• btActionInterface to make it easier to integrate your custom character, vehicle actions into the physics pipeline
• Updated Bullet_User_Manual.pdf for Bullet 2.74
• Numerous other fixes and contributions since 2.73 sp1 release, thanks everyone!

Thanks again everyone for all the contributions.
Please report if there are any issues, and enjoy,
Erwin

Hi,

how is the "Option for one-shot multiple-contact generation" used?

thanks

Hi, thanks for the update! Looking forward to trying out the new features.

I'm using the current SVN version (1610) now, and since a while back the mouse picking of objects in the demo applications has been broken. For example, when trying to pick a cylinder in the CcdPhysicsDemo, the simulation explodes (cylinders flying everywhere quickly), or it aborts due to the assert in btQuaternion for a value of 0. This seems to be a general issue in all demos that allow picking up objects with the mouse. I'm not quite sure at which revision this was broken, I can look further into it if you like.

I'm running this on Linux, 32 bit, and it's compiled with double precision.

Best regards,
Ola

EDIT:
I just tried the Bullet demos in single precision mode. The picking issues are gone, so it seems that the demos are only broken in double precision mode!

A convenience method for btDefaultCollisionConfiguration has just been added in the latest SVN trunk, so it will be available in the next/final Bullet 2.74 release:

Until this convenience method has been added, please use the following snippet. Note that this feature decreases performance, so it is switched off by default.



Picking seems to work fine under Windows 32bit, compiled using double-precision. Did you try a full clean rebuild? We'll do some testing of Linux double-precision built, you can track progress on the issue here.

Thanks for the feedback,
Erwin

Hi Erwin, thanks for the feedback!

I've posted more test results in the issue, I guess the discussion should proceed there. I've tried separate clean builds to be sure it's nothing in my svn directory. The problem still remains.

Best regards,
Ola

Issue should be fixed and final Bullet 2.74 build has been uploaded.

Please keep feedback and discussions in this forum,
Enjoy!
Erwin

Erwin,
has split impulse been re-added in this release ?

Great job, thanks for all Bullet DevTeam members

Great job bullet physics team, you guys ROCKS

Hey! Congrats on the new release!

I'm going to download it, but I have a quick question: Does the new constraint-drawing code use the existing line-drawing callbacks? Or do we have to implement some more functions?

Hello,

All constraint drawing functions are based on btIDebugDraw::drawLine() call
so they should work if you have this function implemented

Thanks,
Roman

Sorry for the late reply, but great news! So I get the new feature for free!