HTML5 Canvas (Continue)
Understanding Coordinates
The fillRect method above had the parameters (0,0,150,75).
This means: Draw a 150×75 rectangle on the canvas, starting at the top left corner (0,0).
The canvas’ X and Y coordinates are used to position drawings on the canvas.
More Canvas Examples
Below are more examples of drawing on the canvas element:
- Line
<!DOCTYPE html>
<html>
<body>
<canvas id=”myCanvas” width=”200″ height=”100″ style=”border:1px solid #c3c3c3;”>
Your browser does not support the canvas element.
</canvas>
<script type=”text/javascript”>
var c=document.getElementById(“myCanvas”
;
var cxt=c.getContext(“2d”;
cxt.moveTo(10,10);
cxt.lineTo(150,50);
cxt.lineTo(10,50);
cxt.stroke();
</script>
</body>
</html>
- Circle
<!DOCTYPE html>
<html>
<body>
<canvas id=”myCanvas” width=”200″ height=”100″ style=”border:1px solid #c3c3c3;”>
Your browser does not support the canvas element.
</canvas>
<script type=”text/javascript”>
var c=document.getElementById(“myCanvas”;
var cxt=c.getContext(“2d”;
cxt.fillStyle=”#FF0000″;
cxt.beginPath();
cxt.arc(70,18,15,0,Math.PI*2,true);
cxt.closePath();
cxt.fill();
</script>
</body>
</html>
- Gradient
<!DOCTYPE html>
<html>
<body>
<canvas id=”myCanvas” width=”200″ height=”100″ style=”border:1px solid #c3c3c3;”>
Your browser does not support the canvas element.
</canvas>
<script type=”text/javascript”>
var c=document.getElementById(“myCanvas”;
var cxt=c.getContext(“2d”;
var grd=cxt.createLinearGradient(0,0,175,50);
grd.addColorStop(0,”#FF0000″;
grd.addColorStop(1,”#00FF00″;
cxt.fillStyle=grd;
cxt.fillRect(0,0,175,50);
</script>
</body>
</html>
- Image
<!DOCTYPE html>
<html>
<body>
<canvas id=”myCanvas” width=”200″ height=”100″ style=”border:1px solid #c3c3c3;”>
Your browser does not support the canvas element.
</canvas>
<script type=”text/javascript”>
var c=document.getElementById(“myCanvas”;
var cxt=c.getContext(“2d”;
var img=new Image();
img.src=”img_flwr.png”;
cxt.drawImage(img,0,0);
</script>
</body>
</html>
HTML5 <canvas> Tag
| Tag | Description |
|---|---|
| <canvas> | Defines graphics |
Tagged with: canvas • Circle • Gradient • html • html5 • Image • Line • tag