Limited availability
The contextlost
event of the OffscreenCanvas
interface is fired if the browser detects that the OffscreenCanvasRenderingContext2D
context is lost. Contexts can be lost for several reasons, such as an associated GPU driver crashes, or the application runs out of memory, and so on.
By default the user agent will attempt to restore the context and then fire the contextrestored
event. User code can prevent the context from being restored by calling Event.preventDefault()
during event handling.
Use the event name in methods like addEventListener()
, or set an event handler property.
addEventListener("contextlost", (event) => { })
oncontextlost = (event) => { }
Event type
A generic Event
.
The code fragment below detects the contextlost
event.
const canvas = new OffscreenCanvas(256, 256);
const gl = offscreen.getContext("2d");
// Do drawing etc
canvas.addEventListener("contextlost", (event) => {
console.log(event);
});
To prevent the context from being restored the event handler code might instead look like this:
canvas.addEventListener("contextlost", (event) => {
event.preventDefault();
});
Specifications Browser compatibility See also
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4