Modifying cursor property for select portion of an element - Javascript Canvas

Javascript examples for Canvas:Example

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Description

Modifying cursor property for select portion of an element

Demo Code

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<html>
   <head> 
      <meta name="viewport" content="width=device-width, initial-scale=1"> 
      <script type="text/javascript" src="https://code.jquery.com/jquery-1.6.2.js"></script> 
      <script type="text/javascript">
    $(window).load(function(){//from  ww w. ja v a 2  s  .c o  m
function findPos(obj) {
    var curleft = 0, curtop = 0;
    if (obj.offsetParent) {
        do {
            curleft += obj.offsetLeft;
            curtop += obj.offsetTop;
        } while (obj = obj.offsetParent);
        return { x: curleft, y: curtop };
    }
    return undefined;
}
// set up triangle
var example = document.getElementById('example');
var context = example.getContext('2d');
context.fillStyle   = '#000';
context.strokeStyle = '#f00';
context.lineWidth   = 1;
context.beginPath();

context.moveTo(10, 10); // give the (x,y) coordinates
context.lineTo(60, 60);
context.lineTo(10, 120);
context.lineTo(10, 10);
context.fill();
context.stroke();
context.closePath();
$('#example').mousemove(function(e) {
    var pos = findPos(this);
    var x = e.pageX - pos.x;
    var y = e.pageY - pos.y;
    var coord = "x=" + x + ", y=" + y;
    var c = this.getContext('2d');
    var p = c.getImageData(x, y, 1, 1).data;
    if(p[3]!='0') $(this).css({cursor:'pointer'});
    else $(this).css({cursor:'default'});
});
    });

      </script> 
   </head> 
   <body> 
      <canvas id="example" width="120" height="120"> 
      </canvas>
   </body>
</html>

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