EdgeBox passes through another edge box. Bug?

cocos2d-x
#1

I have looked at various sources for the answer to my problem however nothing available seems to help.
This question here seems to have the same problem.
I am having difficulty understanding what the difference is between a createBox and createEdgeBox the documentation simply states that createEdgeBox simply creates a hollow body I am not sure what that means and how does it make it different from createBox. Maybu understanding that concept might help me understand why I have the following problem.

I currently have a platform on which objects stand on. This physics object is a static object (the setDynamic method is called with true to make it static).This physics object is created with createEdgeBox method. Now here is the problem if I create an object with createBox and attach it to a sprite , the object collides with the ground and ultimately stands on top of the first object.However when I create another physics object this time with createEdgeBox it does not stand on top of the platform and instead passes through it.Here is my observation

1-object created with createBox and createEdgeBox collide with each other.

2-object created with createEdgeBox (dynamic) and createEdgeBox (static) do not collide with each other and instead the dynamic object passes through the static one. The dynamic object is moving with a very very slow velocity.

Also if it helps I am not setting a setCategoryBitmask for any of these objects. I also noted that if I replace the dynamic EdgeBox with a simple Box create with createBox then it does not pass through the static ground.
Any suggestions on this issue would be very appreciated.

#2

You should only be using edge boxes for the “edges” of your physics world (I think). The idea is that a Box has mass all along the object while the edge box only has mass on the edges (so two edge boxes inside eachother are not colliding whereas a box inside another box would be constantly colliding with it). That’s what it means to be a hollow body (the mass is only on the edges.) I think most of your use cases should be createBox instead of createEdgeBox except for maybe the ground which could be an edgeBox.

Basically, I can think of very few cases where two edgeBoxes should collide. For the most part, two boxes might collide or a box and an edgeBox might collide but edgeBoxes are supposed to be static objects by nature.

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