Box2D Forums

The project i am working on asserts in b2DynamicTree.cpp

in the method AllocateNode : b2b2Assert(m_nodeCount == m_nodeCapacity)

Does this mean no more nodes or objects can be created?

thanks
c

Do I need to increase the m_nodeCapacity from 16 to something else?

c

Still havent had any luck. Can somebody from the box2d developers why this assertion occurs?

Thanks
c

This assertion is occurring because the tree has become corrupt. You may have a buffer overflow or you are referencing memory that is out of scope. This is likely a bug in your code since I have never seen this assert trip before.

However, please try to reproduce the assertion in the C++ testbed and reply with the code that causes the assertion.

Hello, I know this is an old thread, but it came up when I googled the assertion.

I had the same assertion. I made it go away by using the C++ operator "new" to allocate the b2World object pointer. I was using malloc before . Guess what, I'm a C++ newbie. Depending on what I did with the world object, I was also getting the error message:

I guess that has fixed it. So next time someone complains about the assert, you can tell them not to be such a douche and use new instead of malloc.

Added info for random Googlers: I'm using Box2D in Xcode for ios. That's why I'm having to store a pointer, rather than just have the b2World as a normal member variable in a C++ class. Objective C++ only allows you to have a C++ class member variable in an objective C class if the C++ class has a default constructor (b2World doesn't have one), but there is no such restriction on pointers to C++ classes.