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 |
ExampleEdit
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.InheritanceEdit
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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| Specification | Status | Comment |
|---|---|---|
| WebGL 1.0 The definition of 'webglcontextlost' in that specification. |
Recommendation | Initial definition. |