Search found 149 matches

by MaxDZ8
Tue Dec 03, 2013 7:58 am
Forum: General Bullet Physics Support and Feedback
Topic: What can bullet return about collisions?
Replies: 3
Views: 3207

Re: What can bullet return about collisions?

Some minor issues. Do not consider "collisions with triangles" for real. You might do that now, but in general, collision doesn't happen anymore at triangle level believe it or not. The triangle count has been growing faster than processing power on CPU and until GPU collision isn't viable, you cann...
by MaxDZ8
Tue Dec 03, 2013 7:48 am
Forum: General Bullet Physics Support and Feedback
Topic: Setting up bullet
Replies: 2
Views: 2738

Re: Setting up bullet

To compile in VC2012, I just converted the 2010 project file (or maybe the 2008)? No need to deal with .bat, no idea why it's even there. I do recall having a similar problem (not with Bullet however): I had to manually open the xml solution file, somehow an invalid project descriptor got there and ...
by MaxDZ8
Tue Dec 03, 2013 7:42 am
Forum: General Bullet Physics Support and Feedback
Topic: Adding ghost object crashes application.
Replies: 4
Views: 5067

Re: Adding ghost object crashes application.

You have posted roughtly 200 LOCs. When doing that, it's probably better to just dump the whole source instead of cutting it in snippets. The problem is often in the global variables and communication between different snippets.
by MaxDZ8
Wed Sep 25, 2013 11:50 am
Forum: General Bullet Physics Support and Feedback
Topic: Collision detection problem
Replies: 6
Views: 5965

Re: Collision detection problem

I'm not really sure you're doing your kinematics correctly because I don't remember what ACTIVE_TAG does... but if memory serves, it doesn't do what you want. Try using setActivationState(DISABLE_DEACTIVATION) instead. The problem arises from performance optimization. Bullet uses a "collision cache"...
by MaxDZ8
Wed Sep 25, 2013 11:41 am
Forum: General Bullet Physics Support and Feedback
Topic: What is the best way for controlling a character?
Replies: 1
Views: 2233

Re: What is the best way for controlling a character?

You don't need to do that. Kinematics are not affected by physics in any way. They won't move, won't rotate, won't be affected by gravity. Will happily go around encroaching other objects. If the other object is dynamic, it will be pushed away, otherwise nothing will happen. Personally I believe usi...
by MaxDZ8
Wed Sep 25, 2013 11:34 am
Forum: General Bullet Physics Support and Feedback
Topic: How to tell if a rigid body is on ground?
Replies: 2
Views: 1809

Re: How to tell if a rigid body is on ground?

This is a bit simplistic - which side is "below"? - but correct in practice. I have been doing the collision check for a while and it appears to work just fine. That is, if the collision manifold set is empty, the object is guaranteed to not touch anything and thus it's probably falling. I use this ...
by MaxDZ8
Fri Sep 13, 2013 4:01 am
Forum: General Bullet Physics Support and Feedback
Topic: How to prevent Projectiles interacting with their Creator?
Replies: 1
Views: 1510

Re: How to prevent Projectiles interacting with their Creato

A solution might involve collision masks and groups. Sadly, those are meant to be static for an object so I'm not quite on them. The correct solution is probably to ask the artist to move the projectile spawn position out of the player/weapon model. But, if everything fails, I'd just do a simple che...
by MaxDZ8
Fri Aug 30, 2013 5:45 am
Forum: General Bullet Physics Support and Feedback
Topic: BspDemo way to load BSP is too slow for big world
Replies: 5
Views: 1831

Re: BspDemo way to load BSP is too slow for big world

And this is how Bullet works - it makes AABBs out of everything in broadphase. I suppose the BSP extraction is just brittle. I have dealt myself with brush extraction in the past and I can indeed understand it can be hard to get right. I always considered it a demo only, not for production uses. In ...
by MaxDZ8
Thu Aug 29, 2013 2:59 pm
Forum: General Bullet Physics Support and Feedback
Topic: Basic question about AA primitives
Replies: 2
Views: 1174

Re: Basic question about AA primitives

I cannot pinpoint them right now, I'm sorry.
But I recall reading something about it on the generic broadphase collision pair generator code (not in the broadphase code) maybe you could try looking in that direction so you could give me a refresh as well.
by MaxDZ8
Thu Aug 29, 2013 2:57 pm
Forum: General Bullet Physics Support and Feedback
Topic: BspDemo way to load BSP is too slow for big world
Replies: 5
Views: 1831

Re: BspDemo way to load BSP is too slow for big world

Are you passing the correct world bounds? I had a similar problem in the past and it turned out a bug in my loader caused bullet to slow to a crawl like you describe.
by MaxDZ8
Mon Aug 26, 2013 10:37 am
Forum: General Bullet Physics Support and Feedback
Topic: [solved] Weird behavior when retrieving stored user pointer
Replies: 5
Views: 1715

Re: Weird behavior when retrieving stored user pointer

myAsset* intersectedAsset) { .. } So I was passing the pointer by copy, not by reference, and when the function returned the pointer was gone. What's in the function body is not irrelevant when dealing with pointers. Even passing out the object by reference does not solve the problem: if the pointe...
by MaxDZ8
Mon Aug 26, 2013 7:01 am
Forum: General Bullet Physics Support and Feedback
Topic: [solved] Weird behavior when retrieving stored user pointer
Replies: 5
Views: 1715

Re: Weird behavior when retrieving stored user pointer

If memory serves, user pointers are not serialized in any way using the default world loader. How are you working around that issue? How do you set up user pointers for world objects?
Personally I've given up that, I couldn't consider it robust. I do a lookup in std::map instead.
by MaxDZ8
Mon Aug 26, 2013 6:57 am
Forum: General Bullet Physics Support and Feedback
Topic: Voxel World, Construct collision model on the fly
Replies: 4
Views: 2138

Re: Voxel World, Construct collision model on the fly

I have seen people do the approach of just making a BvhTriangleMeshShape for the entire world, but especially with a changing world I don't think this is all too viable, or at least I know that I can pick out the right blocks for collisions A LOT easier than just having the entire geometry and then...
by MaxDZ8
Mon Aug 26, 2013 6:52 am
Forum: General Bullet Physics Support and Feedback
Topic: Should you use the kinematic character controller?
Replies: 3
Views: 3536

Re: Should you use the kinematic character controller?

The main problem regarding kinematics is that they are game-dependant and even context-dependant. Personally I believe the provided kinematic controller should be seriously downtoned. I am surprised to keep reading about people using dynamic objects instead of kinematics and finding them a good solu...
by MaxDZ8
Thu Jun 06, 2013 5:23 am
Forum: General Bullet Physics Support and Feedback
Topic: Bullet Character Controller Tutorial or Demo
Replies: 10
Views: 11052

Re: Bullet Character Controller Tutorial or Demo

With rigid body characters, you do have access to the current speed of the character so you can basically make it do whatever you want by applying the right forces Sure, if you know what those forces mean. Have you ever tried explaining that to an artist? How do you provide warping? What about obje...