HTML5 Canvas - Styles and Colors


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HTML5 canvas provides following two important properties to apply colors to a shape −

Sr.No. Method and Description
1 fillStyle

This attribute represents the color or style to use inside the shapes.

2 strokeStyle

This attribute represents the color or style to use for the lines around shapes

By default, the stroke and fill color are set to black which is CSS color value #000000.

A fillStyle Example

Following is a simple example which makes use of above mentioned fillStyle attribute to create a nice pattern.

<!DOCTYPE HTML>
<html>
   <head>
      
      <style>
         #test {
            width: 100px;
            height:100px;
            margin: 0px auto;
         }
      </style>
      
      <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');
               
               // Create a pattern
               for (var i=0;i<7;i++){
                  
                  for (var j=0;j<7;j++){   
                     ctx.fillStyle='rgb(' + Math.floor(255-20.5*i)+ ','+ Math.floor(255 - 42.5*j) + ',255)';
                     ctx.fillRect( j*25, i* 25, 55, 55 );
                  }
               }
            }
            
            else {
               alert('You need Safari or Firefox 1.5+ to see this demo.');
            }
         }
      </script>
   </head>
   
   <body id="test" onload="drawShape();">
      <canvas id="mycanvas"></canvas>
   </body>

</html>

The above example would produce following result −

A strokeStyle Example

Following is a simple example which makes use of above mentioned fillStyle attribute to create another nice pattern.

<!DOCTYPE HTML>
<html>
   <head>
      
      <style>
         #test {
            width: 100px;
            height:100px;
            margin: 0px auto;
         }
      </style>
      <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');
               
               // Create a pattern
               for (var i=0;i<10;i++){
               
                  for (var j=0;j<10;j++){
                     ctx.strokeStyle='rgb(255,'+ Math.floor(50-2.5*i)+','+ Math.floor(155 - 22.5 * j ) + ')';
                     ctx.beginPath();
                     
                     ctx.arc(1.5+j*25, 1.5 + i*25,10,10,Math.PI*5.5, true);
                     ctx.stroke();
                  }
               }
            }
            
            else {
               alert('You need Safari or Firefox 1.5+ to see this demo.');
            }
         }
      </script>
   </head>
   
   <body id="test" onload="drawShape();">
      <canvas id="mycanvas"></canvas>
   </body>
   
</html>

The above example would produce following result −


html5_canvas.htm

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