Real-Time Physics Simulation Forum

Ok, thats the problem. Client on win32 is compiling as debug. Server compiling in release. That has a huge effect during collision detection , right? When I compile client in release, it keeps up with server. How many collision objects should I consider a max in a single world? What is best way to c...

Hi, I'd like to discuss btDiscreteDynamicsWorld::stepSimulation. I thought I had this resolved long ago, but timing issues have reared their ugly head once again. In particular, my server and client simulations are running at very different rates. I noticed my frame rate on the client was down so I ...

Ok thanks for clarifying.

Hello, I have looked through the docs but can't find how to adjust the collision group and/or collision mask after adding a btRigidBody to a btDiscreteDynamicsWorld Here's how I am doing the original add: //Entity collides with other entities, terrain and walls m_world->addRigidBody( m_body, COLLISI...

Hello I am using raycasting for mouse picking and its working well. However, the result points to the first object that the ray collided with. Makes sense as I am using btCollisionWorld::ClosestRayResultCallback to retrieve the collision object. So what if I want to find the next collision object, i...

Magmatwister wrote:Nevermind!

Ah I think the OP may be as embarrased as me.

I had, for some reason, changed my VS proiject to link to bullet-2.77/msvc9/libs/debug/BulletCollision.lib rather than bullet-2.77/libs/libbulletcollision.lib (likewise with libbulletdynamics.lib and libbulletmath.lib)

hth

Did you find the problem?

I have similar problem after upgrade to 2.77. Link error with btcollisionshape::getContactBreakingThreshold

Sorry, my mistake. My falling cube generates 12 new contacts per contact point, with clearManifold() active.

I guess thats the slight bouncing and is manageable.

Could I use the impulse to only acknowledge large impacts?

Hi Flix, thanks for your input. I havent had time to try your example code yet, but unfortunately, not clearing the manifold doenst really affect the flow of contacts. I get a continous flow of contacts all with a life time of 1. If I change my test to if ( pt.getLifeTime() == 2 ) I get no contact d...

Hello, I am detecting collision events by iterating over manifolds. Trouble is I get A LOT of collisions. In my test case, I have a single box which drops onto some terrain. Despite my best effort I still get 330 collisions detected by the following code // Iterate over contact manifolds / points: i...

You should use applyTorque to change the rotation of the box, not by setting its transform directly.

You are moving the box past the ball, not allowing the box to push the ball around

Ah bullet is great,

I just need the collisioncallback hitPointWorld, then cross reference it with my scaled data set.

Nice

Hi,

I can get raycasts to hit heightmaps with ease thanks to bullet.

Is there any way to calculate the point at which a raycast intersects at btHeightFieldTerrainShape?

I'd like to know the exact btVector3 coords of the intersection?


Thanks

Simon

Zeal wrote:Not sure how to do the rotation though... I dont want the user to pitch more than -90 to +90 degrees (yaw can go a full 360 degrees). How can I clamp these angles?

This is something I am also interested in but have not yet resolved. Contrainsts perhaps?

bump