Search for node inside circle (SKShapeNode) with lowest y-coordinate - ios

Question

I want to search for nodes inside a circle - the circle is a SKShapeNode. The return node (SKSpriteNode) should be the nodes found inside the circle, with the lowest y-value.
For people who are interested, this is the code I use for the search:
SKSpriteNode *currentNode = [SKSpriteNode spriteNodeWithColor:[UIColor clearColor] size:CGSizeMake(0, 0)];
[currentNode setPosition:CGPointMake(0, 99999)];
SKShapeNode *circle = [SKShapeNode shapeNodeWithCircleOfRadius:100];
// adding circle and other nodes to scene
[self enumerateChildNodesWithName://* usingBlock:^(SKSpriteNode *foundNode, BOOL * _Nonnull stop) {
if ([circle containsPoint:currentNode.position]) {
if (currentNode.position.y > foundNode.position.y) {
currentNode = foundNode;
}
}];
// currentNode = node inside circle with lowest y
I don't like this solution, looks like it takes too much effort to find just the one node. I also tried using nodesAtPoint/nodeAtPoint but that does not work in my project - 'big' child nodes.
I am curious: is there an easier way to search for a node with specifics like this?

Answer 1

Checking the Y coordinate is going to be much faster than [circle containsPoint] so you might want to change the order of your condition to first compare the y coordinate of candidate nodes and only check circle containsPoint for nodes that have a y coordinate between the lowest point of your circle (-100) and the currentNode's Y coordinate.
something like :
if ( foundNode.position.y > -100
&& foundNode.position.y < currentNode.position.y )
{
if ([circle containsPoint:foundNode.position])
{ currentNode = foundNode }
}
note: i'm assuming enemy.position was actually meant to be foundNode.position.