Question

Let’s say I have a parent node with N child nodes. They all have scheduled updates on every frame. Whose update: selector gets called first, the child nodes or the parent? Is there any set order?

Answer 1

The visit method in CCNode has the following code:

if(children_) {
    ccArray *arrayData = children_->data;
    NSUInteger i = 0;

    // draw children zOrder < 0
    for( ; i < arrayData->num; i++ ) {
        CCNode *child = arrayData->arr[i];
        if ( [child zOrder] < 0 )
            [child visit];
        else
            break;
    }

    // self draw
    [self draw];

    // draw children zOrder >= 0
    for( ; i < arrayData->num; i++ ) {
        CCNode *child =  arrayData->arr[i];
        [child visit];
    }

So, as you can see, first are visited children whose zOrder is less than zero, then the current node (the children’s parent) is drawn, then the rest of children is also visited (note that visiting a node will eventually draw it, according to the criteria just explained).