Math.Random - Javascript

Question

I've this code:

            var num = 550;
            $(document).keydown(function (event) {
                switch (event.keyCode) {
                    // Left Arrow                
                    case 37: num = num-- - 15;
                        document.getElementById('player').style.margin = '550px ' + num + 'px 0px ';
                        break;
                    // Right Arrow                
                    case 39: num = 15 + num++;
                        document.getElementById('player').style.margin = '550px ' + num + 'px 0px ';
                        break;
                }
            });
            var nump = 0;
            var touch = false;
            var flagtouch;
            $(document).ready(function () {
                flagtouch = setInterval(function () {
                    movePoint(nump);

                }, 10);
            });
            function movePoint() {
                document.getElementById('point').style.margin = nump + 'px 615px 0px';
                touch = chekTouch($('#point'), $('#player'))   // check whether the divs touches and return true if touched
                if (touch) {
                    $('.point').ready(function () {
                        var docWidth = $(document).width();
                        var $div = $('.point');
                        var divWidth = $div.width();
                        var widthMax = docWidth - divWidth;
                        $div.css({
                            marginLeft: Math.floor(Math.random() * widthMax),
                            marginTop: 150,
                        });
                    });
                }
                else {
                    nump++;
                }
            }

            function chekTouch($div1, $div2) {
                var x1 = $div1.offset().left;
                var y1 = $div1.offset().top;
                var h1 = $div1.outerHeight();
                var w1 = $div1.outerWidth();
                var b1 = y1 + h1;
                var r1 = x1 + w1;
                var x2 = $div2.offset().left;
                var y2 = $div2.offset().top;
                var h2 = $div2.outerHeight();
                var w2 = $div2.outerWidth();
                var b2 = y2 + h2;
                var r2 = x2 + w2;

                if (b1 < y2 || y1 > b2 || r1 < x2 || x1 > r2) return false;
                return true;
            }

Now, I got this touch function, when div point touches div player he excute marginLeft in random way and marginTop to 0px.

So its working but only 1 issue, the random isn't stop working, he keep move when the div has physicall contact each other.

My question is how can I make the random margin work only when he touch the div?

Thanks!

Answer 1

// - it is because you are using setInterval which plays forever every 10ms

Edit:

Sorry I misunderstood what you meant,

after it touches you should clear the interval like this :

clearInterval(flagtouch);

then the loop will stop

DEMO

Answer 2

In movePoint() , after you set the randomly set the margin when touch was true , you still set the margin with document.getElementById('point').style.margin = nump + 'px 615px 0px'; at every interval, but don't increase nump , so touch will always be true after that.