35 lines
911 B
JavaScript
35 lines
911 B
JavaScript
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import { blob } from './fetch.mjs';
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import { rewriteUrl } from './cors.mjs';
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// ****************************** load images *********************************
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// load an image from a blob or url
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const loadImg = (imgData, cors = false) => new Promise((resolve) => {
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const img = new Image();
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img.onload = (e) => {
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resolve(e.target);
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};
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if (imgData instanceof Blob) {
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img.src = window.URL.createObjectURL(imgData);
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} else {
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let url = imgData;
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if (cors) url = rewriteUrl(imgData);
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img.src = url;
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}
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});
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// preload an image
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// the goal is to get it in the browser's cache so it is available more quickly when the browser needs it
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// a list of cached icons is used to avoid hitting the cache multiple times
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const cachedImages = [];
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const preloadImg = (src) => {
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if (cachedImages.includes(src)) return false;
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blob(src);
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// cachedImages.push(src);
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return true;
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};
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export {
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loadImg,
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preloadImg,
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};
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