Search found 50 matches

by S1L3nCe
Mon Jun 15, 2020 7:37 am
Forum: General Bullet Physics Support and Feedback
Topic: Can bullet be used for 2D collision detection?
Replies: 1
Views: 3672

Re: Can bullet be used for 2D collision detection?

Hello, There is 2D shapes in Bullet (Convex2DShape and Box2DShape) Otherwise you can lock linear and angular axis of RigidBodies with setLinearFactor and setAngularFactor https://web.archive.org/web/20170602065151/http://bulletphysics.org/mediawiki-1.5.8/index.php/Code_Snippets Box2D engine should b...
by S1L3nCe
Fri Jun 12, 2020 8:28 am
Forum: General Bullet Physics Support and Feedback
Topic: Proximity Detection using AABB Trees
Replies: 3
Views: 4959

Re: Proximity Detection using AABB Trees

Found viewtopic.php?t=6195#p21693 on this forum.
It does not handle constraint between ghost objects and bodies to make them move together but it's a good start to know how to create ghost objects and handle collisions detection.
by S1L3nCe
Wed Jun 10, 2020 2:30 pm
Forum: General Bullet Physics Support and Feedback
Topic: Tunnelling at very low velocity
Replies: 2
Views: 3630

Re: Tunnelling at very low velocity

Hello, I never used APPGameKit and don't know how it use Bullet but on what I see on your video: Try to better scale your objects. Avoid large scale, keep size in range [0.05,10]m (see https://web.archive.org/web/20170713085948/http://www.bulletphysics.org/mediawiki-1.5.8/index.php/Scaling_The_World...
by S1L3nCe
Tue Jun 09, 2020 11:41 am
Forum: General Bullet Physics Support and Feedback
Topic: Proximity Detection using AABB Trees
Replies: 3
Views: 4959

Re: Proximity Detection using AABB Trees

Hi,

I think Ghost Object is the thing I would use here.
With a bigger size than the object it is paired with, it will be able to detect any other overlapping physic object before the collision.
by S1L3nCe
Tue Jun 02, 2020 9:55 pm
Forum: General Bullet Physics Support and Feedback
Topic: Combining two Rigid Bodies?
Replies: 10
Views: 17624

Re: Combining two Rigid Bodies?

Yes if you need to link 2 existing RigidBodies you have to use constraints . Here is some of them with explanations : https://knowledge.autodesk.com/support/maya/learn-explore/caas/CloudHelp/cloudhelp/2015/ENU/Maya/files/GUID-CDB3638D-23AF-49EF-8EF6-53081EE4D39D-htm.html For your example, the Fixed ...
by S1L3nCe
Tue Jun 02, 2020 7:22 pm
Forum: General Bullet Physics Support and Feedback
Topic: Combining two Rigid Bodies?
Replies: 10
Views: 17624

Re: Combining two Rigid Bodies?

It allows to combine different shapes in the Compound one to create a single RigidBody so you have only one mass to handle. On your exemple, you will create 2 btBoxShape, add them as child in a btCompoundShape and then create a RigidBody based on the Compound shape. You can find sample code here htt...
by S1L3nCe
Tue Jun 02, 2020 3:58 pm
Forum: General Bullet Physics Support and Feedback
Topic: Combining two Rigid Bodies?
Replies: 10
Views: 17624

Re: Combining two Rigid Bodies?

Hello,

Compounds shapes exists for this purpose.
You can combine several shapes in a Compound shape and then use it to create a single RigidBody.
by S1L3nCe
Fri Apr 12, 2019 4:10 pm
Forum: General Bullet Physics Support and Feedback
Topic: Model Scaling
Replies: 11
Views: 19170

Re: Model Scaling

You will scale values gived to Bullet so you will need to unscale values coming from Bullet to use them. The fastest way is to use methods like xxx_to_bullet and bulet_to_xxx With vector3, the first one will take a vector3 used in your project and will generate a btVector3 where the scale factor has...
by S1L3nCe
Tue Apr 09, 2019 12:47 pm
Forum: General Bullet Physics Support and Feedback
Topic: Model Scaling
Replies: 11
Views: 19170

Re: Model Scaling

I'm not very aware on this subject anymore but I think this tutorial is still relevant.
by S1L3nCe
Tue Apr 09, 2019 9:06 am
Forum: General Bullet Physics Support and Feedback
Topic: Model Scaling
Replies: 11
Views: 19170

Re: Model Scaling

Hi,

I don't know when the wiki will be back but you could still access some tutorials with this:
https://web.archive.org/web/20170706235 ... /Main_Page

Yours is in Various Tutorial Articles>Scaling The World :)
by S1L3nCe
Mon Jan 15, 2018 9:00 am
Forum: General Bullet Physics Support and Feedback
Topic: Custom Collision Filtering with Broadphase Callback (Bitmask)
Replies: 1
Views: 3828

Re: Custom Collision Filtering with Broadphase Callback (Bitmask)

Even if there are 15 max different mask&group it allows a lot of combination as you can change mask&group of a body in run time. Otherwise: m_clientObject in btBroadphaseProxy is what you are looking for. It's probably the userPtr of the relevant btBody. (see btBroadphaseProxy constructor) Y...
by S1L3nCe
Fri Sep 01, 2017 7:40 am
Forum: General Bullet Physics Support and Feedback
Topic: Best way to use collision mesh from a 3d model (.obj) file?
Replies: 1
Views: 4959

Re: Best way to use collision mesh from a 3d model (.obj) fi

Hi, As described here in Meshes section : http://bulletphysics.org/mediawiki-1.5.8/index.php/Collision_Shapes Best way for static mesh object is to use btBvhTriangleMeshShape (this is only for static object) For dynamic object, btConvexHullShap. And optionally btHeightfieldTerrainShape for your heig...
by S1L3nCe
Thu Aug 31, 2017 5:50 pm
Forum: General Bullet Physics Support and Feedback
Topic: AngularFactor == 0 but AngularVelocity != 0
Replies: 5
Views: 7286

Re: AngularFactor == 0 but AngularVelocity != 0

It's weird indeed. How much is the difference each steps ?

Otherwise, you can use the tick callback system to set 0 velocity to your body.
by S1L3nCe
Thu Aug 31, 2017 4:51 pm
Forum: General Bullet Physics Support and Feedback
Topic: AngularFactor == 0 but AngularVelocity != 0
Replies: 5
Views: 7286

Re: AngularFactor == 0 but AngularVelocity != 0

Hi,

You should use setAngularVelocity instead of setAngularFactor in order to reset your object angular velocity