HTMLCanvasElement: webglcontextlost event

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.

This event does not bubble.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("webglcontextlost", (event) => { })

onwebglcontextlost = (event) => { }

Event type

A WebGLContextEvent. Inherits from Event.

Event properties

This interface inherits properties from its parent interface, Event.

WebGLContextEvent.statusMessage

A read-only property containing additional information about the event.

Example

With the help of the WEBGL_lose_context extension, you can simulate the webglcontextlost event:

const canvas = document.getElementById("canvas");
const gl = canvas.getContext("webgl");

canvas.addEventListener("webglcontextlost", (event) => {
  console.log(event);
});

gl.getExtension("WEBGL_lose_context").loseContext();

// "webglcontextlost" event is logged.

Specifications

Browser compatibility

See also

• WebGLContextEvent
• WebGLRenderingContext.isContextLost()
• WEBGL_lose_context, WEBGL_lose_context.loseContext(), WEBGL_lose_context.restoreContext()