## Search found 44 matches

Mon Dec 02, 2019 8:58 am
Forum: General Bullet Physics Support and Feedback
Topic: Get Forward, Right, Up Vector From Transformation Matrix
Replies: 1
Views: 109

### Re: Get Forward, Right, Up Vector From Transformation Matrix

It was actually rather simple: void moveForward(const btScalar& Speed) { btTransform Trans = _RigidBody->getWorldTransform(); const btVector3 Forward = Trans(btVector3(1 * Speed, 0, 0)); Trans.setOrigin(Forward); _RigidBody->activate(true); _RigidBody->setWorldTransform(Trans); } void moveBackward(c...
Sun Dec 01, 2019 10:54 pm
Forum: General Bullet Physics Support and Feedback
Topic: Get Forward, Right, Up Vector From Transformation Matrix
Replies: 1
Views: 109

### Get Forward, Right, Up Vector From Transformation Matrix

How can I get a Forward, Right, and Up Vector from a Transformation Matrix? I want to use these vectors as a basis to apply force to rigid bodies in different directions. btTransform Trans = _RigidBody->getWorldTransform(); btVector3 Forward; // ??? btVector3 Right; // ??? btVector3 Up; // ??? _Rigi...
Sun Dec 01, 2019 3:36 pm
Forum: General Bullet Physics Support and Feedback
Topic: My V-HACD Integration
Replies: 3
Views: 201

### Re: My V-HACD Integration

So there was an issue computing the center of mass. V-HACD computes the center position for each convex hull during decomposition. I have greatly reduced the complexity of reading decomp results and here is the resulting code: #pragma once #include <VHACD.h> // // Structure containing objects create...
Fri Nov 29, 2019 7:08 pm
Forum: General Bullet Physics Support and Feedback
Topic: My V-HACD Integration
Replies: 3
Views: 201

### Re: My V-HACD Integration

Okay I mistakenly ran in debug mode. In release we have a constant 60+fps with hundreds of objects. It just goes to show though that these shapes do take a considerable more amount of computing power. I never had slowdowns like that in debug mode using basic collision shapes. I'm sure the complexity...
Fri Nov 29, 2019 6:59 pm
Forum: General Bullet Physics Support and Feedback
Topic: My V-HACD Integration
Replies: 3
Views: 201

### Re: My V-HACD Integration

Well after just a few of these are created into the world, collisions make FPS drop below 15. I am reusing the collision shapes of duplicate objects to help improve bullets performance. It doesn't seem to matter with these collision shapes being used.. http://i.imgur.com/VvEWwqYh.gif https://i.imgur...
Fri Nov 29, 2019 6:46 pm
Forum: General Bullet Physics Support and Feedback
Topic: My V-HACD Integration
Replies: 3
Views: 201

### My V-HACD Integration

Hello, I spent the morning creating this function that takes an object containing vectors of vertices and indices, runs it through V-HACD , and spits out a btCompoundShape. I have tested it and everything appears to be functioning properly but I would like the community experts to take a look and se...
Wed Nov 27, 2019 2:14 pm
Forum: General Bullet Physics Support and Feedback
Topic: Creating A btGImpactMeshShape
Replies: 0
Views: 169

### Creating A btGImpactMeshShape

I was searching for how to create a btGimpactTriangleMeshShape as stated in the user manual and stumbled upon this github issue https://github.com/bulletphysics/bullet3/issues/2392 stating that it was actually a btGImpactMeshShape. A commenter stated that you must also register the btGImpactCollisio...
Sat Jan 20, 2018 5:06 pm
Forum: General Bullet Physics Support and Feedback
Topic: Where Are Bullet3 Examples/Tutorials?
Replies: 1
Views: 1590

### Where Are Bullet3 Examples/Tutorials?

Where are the examples/tutorials for bullet3? All the provided examples use the bullet2 api. Does anyone know where I can find a basic hello world tutorial for the newer bullet3 api? Something to demonstrate which headers to include, how to properly initialize the library, adding a few rigid bodies,...
Fri Oct 03, 2014 11:28 am
Forum: General Bullet Physics Support and Feedback
Topic: 'Welding' Objects Together
Replies: 4
Views: 2592

### Re: 'Welding' Objects Together

I already assumed I could use a btCompoundShape but hoped to avoid that route. If you can specify a distance between the joints on a 6Dof constraint that might be exactly what I was looking for, I'll check the constraint demo again. As a side note, it looks like the 6Dof constraint can do everything...
Wed Oct 01, 2014 1:20 am
Forum: General Bullet Physics Support and Feedback
Topic: 'Welding' Objects Together
Replies: 4
Views: 2592

### 'Welding' Objects Together

I'm trying to essentially parent two objects without actually parenting them since I've read that two dynamic objects can't/shouldn't be parented together. I've created a quick video visualizing my question along with much more detailed audio explanation. https://www.youtube.com/watch?v=uSgdZnB5zDM ...
Mon Sep 29, 2014 8:32 pm
Forum: General Bullet Physics Support and Feedback
Topic: The Broadphase
Replies: 5
Views: 3123

### Re: The Broadphase

Thank you xexuxjy. My original thought was to look into Simulation Island's and see if that mechanism could give me the data I'm looking for however I read in a few very old topics that they are only used for objects that have gone into their sleep state. More information about Simulation Island's a...
Fri Sep 26, 2014 10:47 pm
Forum: General Bullet Physics Support and Feedback
Topic: The Broadphase
Replies: 5
Views: 3123

### Re: The Broadphase

Thank you, I appreciate your help Basroli. What I've been able to gather is eventually all objects that can collide will end up in the tree, hopefully this means that no objects in the simulation are left out of the tree, unless of course maybe idle objects. It also sounds like it is possible to sea...
Fri Sep 26, 2014 9:44 am
Forum: General Bullet Physics Support and Feedback
Topic: The Broadphase
Replies: 5
Views: 3123

### The Broadphase

I'm looking for some more detailed information about the btDbvtBroadphase. It is to my understanding that the broadphases purpose is to group individual objects into small lists based on how likely they are to collide. Could someone give a more detailed explanation about this? If my assumption of th...
Sat Sep 13, 2014 3:37 pm
Forum: General Bullet Physics Support and Feedback
Topic: Do I need a 3D renderer if bullet has a debug drawer ??
Replies: 1
Views: 1842

### Re: Do I need a 3D renderer if bullet has a debug drawer ??

The debug drawing is simply that, rendering the debugging information. If your motivation behind using Bullet is for some scientific research, robotics engineering, etc.. then that should be sufficient. If you're trying to develop an interactive application then your not going to be able to get the ...
Tue Sep 09, 2014 7:27 pm
Forum: General Bullet Physics Support and Feedback
Topic: Telling Bullet That Something Happened In The Past
Replies: 28
Views: 9710

### Re: Telling Bullet That Something Happened In The Past

Predicting interactions with programmed events and standard dynamic objects not affected by a second player is easy. The issue is trying to predict player actions that will result in a change in what the predicted physics see. How much would predicting players cost you? 1ms? 100ms? 1 failed update ...