The HTML5 <canvas> tag is used to draw graphics, animations, etc. using scripting. It is a new tag introduced in HTML5. The canvas element has a DOM method called getContext, which obtains rendering context and its drawing functions. This function takes one parameter, the type of context 2d.
To draw a Quadratic curve with HTML5 canvas, use the quadraticCurveTo() method. This method adds the given point to the current path, connected to the previous one by a quadratic Bezier curve with the given control point.
You can try to run the following code to learn how to draw a quadratic curve on HTML5 Canvas. The x and y parameters in quadraticCurveTo() method are the coordinates of the endpoint. cpx and cpy are the coordinates of the control point.
Example
<!DOCTYPE html>
<html>
<head>
<title>HTML5 Canvas Tag</title>
</head>
<body>
<canvas id="newCanvas" width="500" height="300" style="border:1px
solid #000000;"></canvas>
<script>
var c = document.getElementById('newCanvas');
var ctx = c.getContext('2d');
// Draw shapes
ctx.beginPath();
ctx.moveTo(75,25);
ctx.quadraticCurveTo(25,25,25,62.5);
ctx.quadraticCurveTo(25,100,50,100);
ctx.quadraticCurveTo(50,120,30,125);
ctx.quadraticCurveTo(60,120,65,100);
ctx.quadraticCurveTo(125,100,125,62.5);
ctx.quadraticCurveTo(125,25,75,25);
ctx.stroke();
</script>
</body>
</html>Output
