This example shows how you can specify context attributes when creating a canvas context, and then call getContextAttributes() to read back the actual parameters that the browser used.
const logElement = document.getElementById("log");
function log(text) {
logElement.innerText += text;
}
First we create a context using HTMLCanvasElement.getContext(), specifying just one context attribute.
let canvas = document.createElement("canvas");
let ctx = canvas.getContext("2d", { alpha: false });
If the getContextAttributes() method is supported, we use it to read back the actual attributes used by the browser (including those we explicitly specified):
if (ctx.getContextAttributes) {
const attributes = ctx.getContextAttributes();
log(JSON.stringify(attributes));
} else {
log("CanvasRenderingContext2D.getContextAttributes() is not supported");
}
Depending on the attributes supported by the browser, the log below should display a string that looks something like: {alpha: false, colorSpace: 'srgb', desynchronized: false, willReadFrequently: false}
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