The webglcontextlost event of the WebGL API is fired if the user agent detects that the drawing buffer associated with a WebGLRenderingContext object has been lost.
| Bubbles | Yes |
| Cancelable | Yes |
| Target objects | HTMLCanvasElement |
| Interface | WebGLContextEvent |
Example
With the help of the WEBGL_lose_context extension, you can simulate the webglcontextlost event:
var canvas = document.getElementById('canvas');
var gl = canvas.getContext('webgl');
canvas.addEventListener('webglcontextlost', function(e) {
console.log(e);
}, false);
gl.getExtension('WEBGL_lose_context').loseContext();
// "webglcontextlost" event is logged.
Inheritance
The webglcontextlost event implements the WebGLContextEvent interface, which inherits from Event. You can use the properties and methods defined on these interfaces.
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Specifications
| Specification | Status | Comment |
|---|---|---|
| WebGL 1.0 The definition of 'webglcontextlost' in that specification. |
Recommendation | Initial definition. |
Browser compatibility
| Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|---|
| Basic support | 9 | (Yes) | 4.0 (2.0) | 11 | 12 | 5.1 |
| Feature | Android | Chrome for Android | Edge | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|---|
| Basic support | ? | 25 | (Yes) | 4.0 (2.0) | ? | 12 | 8.0 |