Problem with Parent Looping?

Why is Parent Looping a bad thing/not supported in the bge (with ctrl+p)?

Wouldnt it be just: if one moves, the other moves too?

So… what is the problem with Parent Looping?

if you have 2 cubes, and you parent 1 to the other, if the parent moves then the child moves too. but the child can move separately without affecting the parent’s movement.
if you want something like if I move cube 1 then cube 2 moves too and if I move cube 2 then cube 1 moves with it you could join them(ctrl j)

What do you mean with “Parent Looping”?

He means when you try to parent the child object to the parent, you get the error message: Loop in parents

I think that’s what hé means.


but my question was just theoretical, i know how to parent objects :stuck_out_tongue:

Then it wouldn’t be a parent-child relationship.

The parent-child-relationship forms a special graph -> a tree. It has a lot of benefits in terms of managing objects within a scene. That is why it is used. The restriction is … no loops in the scene graph (trees have no loops).

This is not always the best relationship on other aspects (e.g. your game flow). You are not restricted to this one.

What you need is a different kind of relationship.

Here is I would go for:
-> single object (join meshes)
-> compound physics type
-> physics constraint
-> custom behavior (Python)