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iosobjective-csprite-kitsknode

Jumping to a specific SKNode in node hierarchy

I have noticed that the SKNode methods children and childNodeWithName: as the name implies only return results from the children directly below the queried node. i.e. [root children]; will return an NSArray containing the nodes @[CUBE1, CUBE2, CUBE3].

In the diagram below I want to get from the ROOT (SKScene) level down to SPHERE2 so that I can quickly access that nodes children. I was hoping that [root childNodeWithName:@"SPHERE2"]; would traverse the whole hierarchy and return a pointer to SPHERE2

enter image description here

MY QUESTION: Is there something that I have missed that will let me jump into a node tree at a specified point (i.e. using the node name)

I could use properties to store pointers to important positions in the tree and then use these to access and process any child nodes, so that is an option ...

Solution

  • You can use the advanced search syntax described in the SKNode documentation, under Advanced Searches.

    This will search the entire node tree recursively for a node named "SPHERE2", starting from the root node:

    SKNode* sphere2 = [root childNodeWithName:@"//SPHERE2"];

    If you know the path to a specific node, you can also use that quite easily:

    SKNode* triangle3 = [root childNodeWithName:@"/CUBE3/SPHERE2/TRIANGLE3"];

    It should be noted if you need those nodes often, you should cache them in a __weak ivar or weak property because searching nodes by name takes a little while.