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# HTML5 Canvas - Using Images

This tutorial would show how to import and external image into a canvas and then how to draw on that image by using following methods:

SN | Method and Description
--- | ---
1 | beginPath() This method resets the current path.
2 | moveTo(x, y) This method creates a new subpath with the given point.
3 | closePath() This method marks the current subpath as closed, and starts a new subpath with a point the same as the start and end of the newly closed subpath.
4 | fill() This method fills the subpaths with the current fill style.
5 | stroke() This method strokes the subpaths with the current stroke style.
6 | drawImage(image, dx, dy) This method draws the given image onto the canvas. Here image is a reference to an image or canvas object. x and y form the coordinate on the target canvas where our image should be placed.

# Example:

Following is a simple example which makes use of above mentioned methods to import an draw on an image.

    <!DOCTYPE HTML>
    <html>
    <head>
    <script type="text/javascript">
    function drawShape(){
      // get the canvas element using the DOM
      var canvas = document.getElementById('mycanvas');

      // Make sure we don't execute when canvas isn't supported
      if (canvas.getContext){

        // use getContext to use the canvas for drawing
        var ctx = canvas.getContext('2d');

        // Draw shapes
        var img = new Image();
        img.src = '/images/backdrop.jpg';

        img.onload = function(){
           ctx.drawImage(img,0,0);
           ctx.beginPath();
           ctx.moveTo(30,96);
           ctx.lineTo(70,66);
           ctx.lineTo(103,76);
           ctx.lineTo(170,15);
           ctx.stroke();
       }

      } else {
        alert('You need Safari or Firefox 1.5+ to see this demo.');
      }
    }
    </script>
    </head>
    <body onload="drawShape();">
       <canvas id="mycanvas"></canvas>
    </body>
    </html>

Assuming we have following image to import images/backdrop.jpg.

The above example would draw following shape:

To learn above concept - Do Online Practice using latest version of either Safari or Opera.

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