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static bool CustomMaterialCombinerCallback(btManifoldPoint& cp, const btCollisionObject* colObj0,int partId0,int index0,const btCollisionObject* colObj1,int partId1,int index1)
{
cp.m_lateralFrictionInitialized = true;
cp.m_lateralFrictionDir1.setValue(1,0,0);
///downscale the friction direction 2 for lower (anisotropic) friction (rather than a unit vector)
cp.m_lateralFrictionDir2.setValue(0,0,0.1);
///choose a target surface velocity in the friction dir1 direction, for a conveyor belt effect
cp.m_contactMotion1 = 1.f;
//cp.m_contactMotion1 = 1.f;
//cp.m_contactCFM2 = 0.1;
//cp.m_combinedFriction = 10;
//cp.m_combinedRestitution = calculateCombinedRestitution(restitution0,restitution1);
return true;
}the code above was posted a few years ago and it should have the effect of a conveyor belt (see http://www.bulletphysics.org/Bullet/php ... ing#p15751). Erwin posted a modified version of the BasicDemo.cpp where the callback is included. There I can achieve that all the boxes drift to the right like on a conveyor belt. but when i try to change the direction of the movement by modifying the two friction directions i get odd behaviour. sometimes the boxes drift in two opposite directions and other times they drift in all directions for example.
so my problem is that i don't know exactly what the parameters and especially the two friction directions effect. can someone tell me what the friction directions exactly do? and perhaps what the other parameters are for?
i thought that the comments explain enough. but it seems that it isn't that easy...
i would be very happy!
Thank you
Gickl