[SOLVED] why fire LeaveCallback when re-add physics for object Model

[dennis.chen]

Hi,

 

 I have added PhysicalTrigger  through scrpit like below:

trigger = add_editor( new PhysicalTrigger( Shape_BOX, position ) );
trigger.setEnterCallback("enterCallBack");
trigger.setLeaveCallback("leaveCallBack");

  void enterCallback(Body body)
  {
        Object object = body.getObject();
        object.setMaterialState("ambient",2,0);
  }

  void leaveCallback(Body body) 
  {
        Object object = body.getObject();
        object.setMaterialState("ambient",1,0);
  }

 

after that ,i added physics for each object through scrpit.when the trigger enter or leave some object,it could be detected.

 

then,i remove these physics through sripts like below and re-added physics when the trigger was inside one of the objects:

 

foreach(Node node; nodes)
{
  if (node.getType()==NODE_OBJECT_MESH)
  {
      Object obj=node_cast(node);
      Body body=obj.getBody();
      obj.setBody(NULL);

      Shape shape=body.getShape(0);//only add one physics
      body.removeShape(shape);
      delete class_append(shape);
      delete class_append(body);
  }
}

 

after "re-added physics" operation,system fire leaveCallback but the parameter of "body" was invalid and caused the application to crash.

 

did i remove physics incorrect?

 

thanks.

[manguste]

Dennis,

 

What caught my eye is that you delete a shape. Body manages the shape, so delete only a body instead.

[dennis.chen]

hi ,maguste,

 

as you mentioned,deleting shapes is redundant.

 

 

As far as my understanding, when the physics trigger enters the object, an enterCallback will be triggered. If at this time I delete this body and re-add another body into the object, it will fire a leaveCallback when updateContacts() calls. However, the problem is the previous body from the entercallback to the leavecallback has already been deleted and therefore it leads to a crash.

So instead what I did is something like this and the app run well:

 

1.clear bodies

2.set trigger callbacks to NULL

3.updateContacts

4.reset trigger callbacks to previous calls.

 

thank you .

[manguste]

If you got it right, that's great. For any future cases, please provide a minimal test scene for reproduction. This way we can check it if it's a bug on our side or (since it's minimal) you go against UnigineScript syntax or logic. Or you can get what's wrong right while creating if :)

[dennis.chen]

thanks! :)