wishthis/node_modules/html2canvas/dist/lib/render/font-metrics.js

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2022-11-19 15:34:10 +00:00
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.FontMetrics = void 0;
var util_1 = require("../core/util");
var SAMPLE_TEXT = 'Hidden Text';
var FontMetrics = /** @class */ (function () {
function FontMetrics(document) {
this._data = {};
this._document = document;
}
FontMetrics.prototype.parseMetrics = function (fontFamily, fontSize) {
var container = this._document.createElement('div');
var img = this._document.createElement('img');
var span = this._document.createElement('span');
var body = this._document.body;
container.style.visibility = 'hidden';
container.style.fontFamily = fontFamily;
container.style.fontSize = fontSize;
container.style.margin = '0';
container.style.padding = '0';
container.style.whiteSpace = 'nowrap';
body.appendChild(container);
img.src = util_1.SMALL_IMAGE;
img.width = 1;
img.height = 1;
img.style.margin = '0';
img.style.padding = '0';
img.style.verticalAlign = 'baseline';
span.style.fontFamily = fontFamily;
span.style.fontSize = fontSize;
span.style.margin = '0';
span.style.padding = '0';
span.appendChild(this._document.createTextNode(SAMPLE_TEXT));
container.appendChild(span);
container.appendChild(img);
var baseline = img.offsetTop - span.offsetTop + 2;
container.removeChild(span);
container.appendChild(this._document.createTextNode(SAMPLE_TEXT));
container.style.lineHeight = 'normal';
img.style.verticalAlign = 'super';
var middle = img.offsetTop - container.offsetTop + 2;
body.removeChild(container);
return { baseline: baseline, middle: middle };
};
FontMetrics.prototype.getMetrics = function (fontFamily, fontSize) {
var key = fontFamily + " " + fontSize;
if (typeof this._data[key] === 'undefined') {
this._data[key] = this.parseMetrics(fontFamily, fontSize);
}
return this._data[key];
};
return FontMetrics;
}());
exports.FontMetrics = FontMetrics;
//# sourceMappingURL=font-metrics.js.map