CanvasRenderingContext2D.createRadialGradient()

The CanvasRenderingContext2D.createRadialGradient() method of the Canvas 2D API creates a radial gradient using the size and coordinates of two circles.

This method returns a CanvasGradient. To be applied to a shape, the gradient must first be assigned to the fillStyle or strokeStyle properties.

Note: Gradient coordinates are global, i.e., relative to the current coordinate space. When applied to a shape, the coordinates are NOT relative to the shape's coordinates.

Syntax

CanvasGradient ctx.createRadialGradient(x0, y0, r0, x1, y1, r1);

The createRadialGradient() method is specified by six parameters, three defining the gradient's start circle, and three defining the end circle.

Parameters

x0
The x-axis coordinate of the start circle.
y0
The y-axis coordinate of the start circle.
r0
The radius of the start circle. Must be non-negative and finite.
x1
The x-axis coordinate of the end circle.
y1
The y-axis coordinate of the end circle.
r1
The radius of the end circle. Must be non-negative and finite.

Return value

CanvasGradient
A radial CanvasGradient initialized with the two specified circles.

Examples

Filling a rectangle with a radial gradient

This example initializes a radial gradient using the createRadialGradient() method. Three color stops between the gradient's two circles are then created. Finally, the gradient is assigned to the canvas context, and is rendered to a filled rectangle.

HTML

<canvas id="canvas" width="200" height="200"></canvas>

JavaScript

var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d');

// Create a radial gradient
// The inner circle is at x=110, y=90, with radius=30
// The outer circle is at x=100, y=100, with radius=70
var gradient = ctx.createRadialGradient(110,90,30, 100,100,70);

// Add three color stops
gradient.addColorStop(0, 'pink');
gradient.addColorStop(.9, 'white');
gradient.addColorStop(1, 'green');

// Set the fill style and draw a rectangle
ctx.fillStyle = gradient;
ctx.fillRect(20, 20, 160, 160);

Result

Specifications

Specification Status Comment
HTML Living Standard
The definition of 'CanvasRenderingContext2D.createRadialGradient' in that specification.
Living Standard  

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic supportChrome Full support YesEdge Full support 12Firefox Full support YesIE Full support YesOpera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support YesOpera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yes

Legend

Full support  
Full support

Gecko-specific notes

  • Starting with Gecko 2.0 (Firefox 4 / Thunderbird 3.3 / SeaMonkey 2.1), specifying non-finite values now throws NOT_SUPPORTED_ERR instead of SYNTAX_ERR.
  • Starting with Gecko 5.0 (Firefox 5.0 / Thunderbird 5.0 / SeaMonkey 2.2), specifying a negative radius correctly throws INDEX_SIZE_ERR.

See also

Document Tags and Contributors

Contributors to this page: mfluehr, mpaulweeks, fscholz, nmve, erikadoyle, Klern
Last updated by: mfluehr,