HTML canvas quadraticCurveTo() Method
Example
Draw a quadratic B�zier curve:
JavaScript:
var c = document.getElementById("myCanvas");
var ctx = c.getContext("2d");
ctx.beginPath();
ctx.moveTo(20, 20);
ctx.quadraticCurveTo(20, 100, 200, 20);
ctx.stroke();
Try it Yourself »
Browser Support
The numbers in the table specify the first browser version that fully supports the method.
| Method | |||||
|---|---|---|---|---|---|
| quadraticCurveTo() | 4.0 | 9.0 | 3.6 | 4.0 | 10.1 |
Definition and Usage
The quadraticCurveTo() method adds a point to the current path by using the specified control points that represent a quadratic B�zier curve.
A quadratic B�zier curve requires two points. The first point is a control point that is used in the quadratic B�zier calculation and the second point is the ending point for the curve. The starting point for the curve is the last point in the current path. If a path does not exist, use the beginPath() and moveTo() methods to define a starting point.
Start point:
moveTo(20, 20)
Control point:
quadraticCurveTo(20, 100, 200, 20)
End point:
quadraticCurveTo(20, 100, 200, 20)
Tip: Check out the bezierCurveTo() method. It has two control-points instead of one.
| JavaScript syntax: | context.quadraticCurveTo(cpx, cpy, x, y); |
|---|
Parameter Values
| Parameter | Description | Play it |
|---|---|---|
| cpx | The x-coordinate of the B�zier control point | Play it » |
| cpy | The y-coordinate of the B�zier control point | Play it » |
| x | The x-coordinate of the ending point | Play it » |
| y | The y-coordinate of the ending point | Play it » |
