Responding to the Mouse on Canvas

by wooozy

HTML

<canvas width="450" height="400" id="myCanvas"></canvas>
<div id="mousepos"></div>
<div id="rectpos"></div>

CSS

#myCanvas{
  background-color:#000;
}

JavaScript

$('#myCanvas').click(function(e){
    var offsetX = $('#myCanvas').offset().left;
    var offsetY = $('#myCanvas').offset().top;
    
   mouseClicked(e.pageX - offsetX , e.pageY - offsetY);
});    


var timer = window.setInterval(callAnimation, 40);

var canvas = document.getElementById('myCanvas');
var context = canvas.getContext('2d');

window.requestAnimFrame = (function (callback) {
    return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame || function (callback) {
        window.setTimeout(callback, 1000 / 60);
    };
})();

var step = 90;

var purpleRectangle = {
    x: 300,
    y: 200,
    xstep: 3,
    ystep: 10,
    width: 100,
    height: 100,
    movement: 'yx',
    borderWidth: 10,
    borderColor: 'white',
    fillColor: 'purple', 
    currentColor: 'yellow'
};



var brownRectangle = 
 {
    x: 100,
    y: 306,
    xstep: 3,
    ystep: 9,
    width: 100,
    height: 100,
    movement: 'y',
    borderWidth: 10,
    borderColor: 'white',
    fillColor: 'brown', 
    currentColor: 'blue' 
};



var rectangles = new Array();
rectangles[0] = purpleRectangle;
rectangles[1] = brownRectangle;




function drawRectangle(r, c) {
    c.beginPath();
    c.rect(r.x, r.y, r.width, r.height);
    c.fillStyle = r.currentColor;
    c.fill();
    c.lineWidth = r.borderWidth;
    c.strokeStyle = r.borderColor;
    c.stroke();
}

function callAnimation() {
    requestAnimFrame(function () {
        animate(rectangles, canvas, context);
    });
}

function mouseClicked(mx, my)
{
    $('#mousepos').html(mx + ":" + my);
    
    for (var i=0; i<rectangles.length; i++)
    {
        if (pointIsInRectangle(mx, my, rectangles[i]))
        {
            $('#mousepos').html('Clicked Rectangle: ' + i);
            rectangles[i].xstep *= -1;
            rectangles[i].ystep *= -1;
        }
    }  
}

function animate(r, can, con)
{
    con.clearRect(0, 0,...