Hello,
I need some clarification about ContactResultCallback::addSingleResult(btManifoldPoint& cp, ...).
1) The easiest first, what is the semantics of the return value (btScalar)? I've noticed that 1.0f or 0 are usually returned.
2) What are cp.m_positionWorldOnA and cp.m_positionWorldOnB?
3) What are cp.m_localPointOnA and cp.m_localPointOnB?
If you could point me to some sketch explaining these values, it will be greatly appreciated.
ContactResultCallback::addSingleResult clarification
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Re: ContactResultCallback::addSingleResult clarification
There was a planned purpose for the return value of addSingleResult, but it is not used so you can ignore it.
The cp.m_positionWorldOnA is the position of the contact point on the surface of object A, same for B, both in world space. cp.m_localPointOnA are the local coordinates of that contact point.
For more details, see my GDC 2010 presentation about contact generation here (slide 14 might help): http://bullet.googlecode.com/files/GDC1 ... ontact.pdf
Thanks,
Erwin
The cp.m_positionWorldOnA is the position of the contact point on the surface of object A, same for B, both in world space. cp.m_localPointOnA are the local coordinates of that contact point.
For more details, see my GDC 2010 presentation about contact generation here (slide 14 might help): http://bullet.googlecode.com/files/GDC1 ... ontact.pdf
Thanks,
Erwin
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Re: ContactResultCallback::addSingleResult clarification
Thanks. The presentation did help a lot.
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Re: ContactResultCallback::addSingleResult clarification
Thanks a lot, I'm glad to have found this.
Although I wonder if this functionnality really requires an abstract callback, for example if I needed a simple raycast, all I needed was to use the default one, which is already implemented.
Although I wonder if this functionnality really requires an abstract callback, for example if I needed a simple raycast, all I needed was to use the default one, which is already implemented.
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Re: ContactResultCallback::addSingleResult clarification
I've inherited ContactResultCallback and overriden addsingleresult, but MSVC 10 still tells me my inherited class is abstract, which was not the case in bullet 2.80.