Question

I am developing a tree game and having dots to add branches on the tree, I want to enhance it for e.g. when one dot get a click then it display other dots within a particular radius around it.

Answer 1

From the description you’ve given, I think you are looking for Distance Formula.

Sqrt((y2-y1)^2 + (x2-x1)^2)

For example:

You have a radius defined and an array of dots:

var radius:int = 20;
var myDots = new Array ({'x':0, 'y': 0}, {'x': 5, 'y': 5}, {'x': 10, 'y': 5}, {'x': 10, 'y': 5}, {'x': 10, 'y': 10});

The dot being clicked is (5,5) and suppose you have a determined radius r=20.
Now, to get all the dots withing the radius r, by iterating in the dots:

    function getDotsWithinRadius(x,y){
        for(var i= 0; i<myDots.length;i++){
            var x2 = myDots[i].x;
            var y2 = myDots[i].y;
            var val = Math.sqrt(Math.pow(y2-y,2) + Math.pow(x2-x, 2)); 
            if(val <=radious){
               /*The dot is with the radius of the give location.
                 This is the place where you tell the current dot to show up or
                 something like that.
                */
            }
        }
    }

I haven’t tested the code but I really hope this gives you an understanding.