Search found 508 matches

by sparkprime
Tue Jul 10, 2012 2:42 pm
Forum: General Bullet Physics Support and Feedback
Topic: simple character movement
Replies: 7
Views: 5031

Re: simple character movement

I wrote a simple character controller as a scripting example for my game engine project. It uses Bullet but uses casts (of cylinders). You may be interested. http://www.gritengine.com/ http://gritengine.svn.sourceforge.net/viewvc/gritengine/grit_core/media/common/actors/init.lua?revision=1895&view=m...
by sparkprime
Sat Nov 05, 2011 8:30 pm
Forum: General Bullet Physics Support and Feedback
Topic: I know I'm going to sound like a total idiot, but...
Replies: 4
Views: 1880

Re: I know I'm going to sound like a total idiot, but...

visual studio express edition is free as in beer
by sparkprime
Fri Sep 09, 2011 8:24 pm
Forum: General Bullet Physics Support and Feedback
Topic: Odd behaviors with Friction and Restitution
Replies: 7
Views: 5719

Re: Odd behaviors with Friction and Restitution

I found CCD sphere sweeping to be very unreliable when I tried it a few years ago and no-longer use it
by sparkprime
Fri Aug 12, 2011 8:59 pm
Forum: General Bullet Physics Support and Feedback
Topic: Bullet wiki or documentation repo?
Replies: 67
Views: 33690

Re: Bullet wiki or documentation repo?

I'm 70% sure I wrote the wiki hello world page, and about 40% sure I wrote the code. Can't remember if I based it on something already written, though.

I wouldn't worry about attribution, personally. Bullet has a very liberal license anyway.
by sparkprime
Mon Aug 08, 2011 4:57 pm
Forum: General Bullet Physics Support and Feedback
Topic: How to create a torus??
Replies: 4
Views: 2301

Re: How to create a torus??

For example, like that :)
by sparkprime
Sun Aug 07, 2011 5:45 pm
Forum: General Bullet Physics Support and Feedback
Topic: How to create a torus??
Replies: 4
Views: 2301

Re: How to create a torus??

You could also make it out of cylinders or something like that.
by sparkprime
Thu Jul 14, 2011 5:00 pm
Forum: General Bullet Physics Support and Feedback
Topic: Recursive btCompoundShape question
Replies: 10
Views: 6274

Re: Recursive btCompoundShape question

The problem is identifying which parts of the compound are in contact, which you want to know for custom physical materials, etc.

I doubt there is a performance problem.
by sparkprime
Wed Mar 02, 2011 6:58 pm
Forum: General Bullet Physics Support and Feedback
Topic: Collision callback that affects collision response
Replies: 5
Views: 1538

Re: Collision callback that affects collision response

I can't have them sleep initially because they need to behave as a static object when objects collide with low impulses.

Setting it up as a joint will not help here -- the impulse applied to the car will still be too large because it will have been chosen before the joint broke.
by sparkprime
Sat Feb 26, 2011 12:59 am
Forum: General Bullet Physics Support and Feedback
Topic: Collision callback that affects collision response
Replies: 5
Views: 1538

Collision callback that affects collision response

I would like to set up a simulation as follows: A streetlamp is a static rigid body (mass==0) comprised of a compound of boxes and cylinders. A car is a compound of convex hulls. A car collides with a street lamp at ~40 mph. I would like the streetlamp to vanish and be replaced with a dynamic fractu...
by sparkprime
Mon Feb 21, 2011 5:11 pm
Forum: General Bullet Physics Support and Feedback
Topic: what's regarded "static"?
Replies: 3
Views: 1300

Re: what's regarded "static"?

If you only want ray tests, you can use that shape for everything.

What you cannot do is test whether two objects are intersecting when their shapes are btBvhTriangleMeshShape.
by sparkprime
Mon Feb 14, 2011 8:24 pm
Forum: General Bullet Physics Support and Feedback
Topic: Improving my Character Controller
Replies: 1
Views: 1412

Re: Improving my Character Controller

I am wondering if a box (for example) would react differently if it found itself intersecting with a static object vs a dynamic object. Would it receive more impulse from the static object?
by sparkprime
Tue Feb 08, 2011 1:48 pm
Forum: General Bullet Physics Support and Feedback
Topic: Is there a concept of a collection in Bullet?
Replies: 2
Views: 1127

Re: Is there a concept of a collection in Bullet?

There is btCompoundShape but this is not a collection of things linked by constraints, rather it is defining a new shape to be the union of its child shapes. AFAIK there is nothing the corresponds to a collection of rigid bodies linked by constraints. Any rigid body can be constrained to any other r...
by sparkprime
Tue Feb 08, 2011 7:11 am
Forum: General Bullet Physics Support and Feedback
Topic: How to make crouching. Change collision shape on the fly?
Replies: 6
Views: 2609

Re: How to make crouching. Change collision shape on the fl

Another cool idea would be to use two capsules joined together by a translation joint. Then when you want to crouch, you can just slide the upper capsule down by applying force. You can also get some good bounciness from your character during jumping when implemented this way. You would rather want...