project/node_modules/zrender/lib/graphic/helper/image.js

55 lines
1.8 KiB
JavaScript

import LRU from '../../core/LRU.js';
import { platformApi } from '../../core/platform.js';
var globalImageCache = new LRU(50);
export function findExistImage(newImageOrSrc) {
if (typeof newImageOrSrc === 'string') {
var cachedImgObj = globalImageCache.get(newImageOrSrc);
return cachedImgObj && cachedImgObj.image;
}
else {
return newImageOrSrc;
}
}
export function createOrUpdateImage(newImageOrSrc, image, hostEl, onload, cbPayload) {
if (!newImageOrSrc) {
return image;
}
else if (typeof newImageOrSrc === 'string') {
if ((image && image.__zrImageSrc === newImageOrSrc) || !hostEl) {
return image;
}
var cachedImgObj = globalImageCache.get(newImageOrSrc);
var pendingWrap = { hostEl: hostEl, cb: onload, cbPayload: cbPayload };
if (cachedImgObj) {
image = cachedImgObj.image;
!isImageReady(image) && cachedImgObj.pending.push(pendingWrap);
}
else {
image = platformApi.loadImage(newImageOrSrc, imageOnLoad, imageOnLoad);
image.__zrImageSrc = newImageOrSrc;
globalImageCache.put(newImageOrSrc, image.__cachedImgObj = {
image: image,
pending: [pendingWrap]
});
}
return image;
}
else {
return newImageOrSrc;
}
}
function imageOnLoad() {
var cachedImgObj = this.__cachedImgObj;
this.onload = this.onerror = this.__cachedImgObj = null;
for (var i = 0; i < cachedImgObj.pending.length; i++) {
var pendingWrap = cachedImgObj.pending[i];
var cb = pendingWrap.cb;
cb && cb(this, pendingWrap.cbPayload);
pendingWrap.hostEl.dirty();
}
cachedImgObj.pending.length = 0;
}
export function isImageReady(image) {
return image && image.width && image.height;
}