Real-Time Physics Simulation Forum

Scan through all your game objects, if the bodies pos is below the water pos then apply an impulse to the body
- this basic method of applying impulses is also useful for explosion/wind effects etc

i dunno if the velocities would have changed before the callback is called - not something i've needed to investigate yet...
i just save variables before calling step simulation and compare them after because i don't want to fill callbacks with lots of extra code!

i play with bullet just for fun, but if accuracy of velocity or speed etc is not so important you could do something simple like i do... during your enviroment creation, set the callback for when manifold points are added: gContactAddedCallback = new_persistent_manifold_collision_point_added; here i...

thanks for the new update. i had a problem with the compound collision destructor: in btCompoundCollisionAlgorithm::~btCompoundCollisionAlgorithm m_dispatcher was undefined (0xcdcdcdcd) so for now i have modified the constructor: btCompoundCollisionAlgorithm::btCompoundCollisionAlgorithm to do m_dis...

here is the modified BasicDemo.cpp from v257 which shows the bug

Thanks i shall modify one of the demos to replicate the problem - currently ive downloaded the new 2.57 but my vc6 is complaining of new and delete being missing a few hundred times during link stage (LNK2001) so i need to sort that first. for now this is a description of how it was going wrong in v...

I do not believe there is any noticible performance difference with whichever cylinder alignment you choose. I tried them all, rotating each physics shapes start orientation to match with the graphic mesh cylinder creation function that i happened to originally code. The same is for all primitives -...

I can change the position of a kinematic body with no problem by reading the current transformation matrix and updating the position and then setting the new transformation. If i change the rotation by a largish step then that is ok too. But, if i do a rotation change that is very small any dynamic ...

seem ok - looks like that is the 0.04 collision margin being added

The general rules is if you create an object it is your responsibility to delete it. If you find deleting something causes a crash then it is easy enough to find the problem. A few minutes spent looking at class constructors and then searching for the particular object variable destruction is simple...

The only time i have had things falling through a landscape is when the graphical mesh does not match the physics mesh... ie. i have set the wrong vertices or winding order in part of the mesh i have given to bullet. As erwin suggested you should 'Implement the btIDebugDrawer interface, so that you ...

many thanks for 2.56... fyi, for the old vc6 enviroment i have had to change btmultisapbroadphase source a little bit: 1. in btMultiSapBroadphase::btMultiSapBroadphase constructor, virtual bool needBroadphaseCollision function, i have to add btMultiSapBroadphase:: in front of the four btMultiSapProx...

body->setActivationState(DISABLE_DEACTIVATION) will keep a body active

i use the btDiscreteDynamicsWorld::removeConstraint(btTypedConstraint* constraint) to remove a constraint between two rigid bodies BEFORE removing the rigid bodies and all works fine. take a look at the function if you are doing something different or are not using a btDiscreteDynamicsWorld (btDiscr...

Hi, i have added a 5th shape to the array of shapes in the appccdphysicsdemo which is a cylinder 1x7x1 in size and replaced the brick wall with an x row of this new shape. when they fall over they do not seem to be correct... whatever 'topple over' angle they are at if they are spinning on their bas...