SQL Operations Studio Public Preview 1 (0.23) release source code

src/vs/editor/browser/config/charWidthReader.ts

@@ -0,0 +1,159 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the Source EULA. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+'use strict';
+
+import { BareFontInfo } from 'vs/editor/common/config/fontInfo';
+
+export const enum CharWidthRequestType {
+	Regular = 0,
+	Italic = 1,
+	Bold = 2
+}
+
+export class CharWidthRequest {
+
+	public readonly chr: string;
+	public readonly type: CharWidthRequestType;
+	public width: number;
+
+	constructor(chr: string, type: CharWidthRequestType) {
+		this.chr = chr;
+		this.type = type;
+		this.width = 0;
+	}
+
+	public fulfill(width: number) {
+		this.width = width;
+	}
+}
+
+interface ICharWidthReader {
+	read(): void;
+}
+
+class DomCharWidthReader implements ICharWidthReader {
+
+	private readonly _bareFontInfo: BareFontInfo;
+	private readonly _requests: CharWidthRequest[];
+
+	private _container: HTMLElement;
+	private _testElements: HTMLSpanElement[];
+
+	constructor(bareFontInfo: BareFontInfo, requests: CharWidthRequest[]) {
+		this._bareFontInfo = bareFontInfo;
+		this._requests = requests;
+
+		this._container = null;
+		this._testElements = null;
+	}
+
+	public read(): void {
+		// Create a test container with all these test elements
+		this._createDomElements();
+
+		// Add the container to the DOM
+		document.body.appendChild(this._container);
+
+		// Read character widths
+		this._readFromDomElements();
+
+		// Remove the container from the DOM
+		document.body.removeChild(this._container);
+
+		this._container = null;
+		this._testElements = null;
+	}
+
+	private _createDomElements(): void {
+		let container = document.createElement('div');
+		container.style.position = 'absolute';
+		container.style.top = '-50000px';
+		container.style.width = '50000px';
+
+		let regularDomNode = document.createElement('div');
+		regularDomNode.style.fontFamily = this._bareFontInfo.fontFamily;
+		regularDomNode.style.fontWeight = this._bareFontInfo.fontWeight;
+		regularDomNode.style.fontSize = this._bareFontInfo.fontSize + 'px';
+		regularDomNode.style.lineHeight = this._bareFontInfo.lineHeight + 'px';
+		regularDomNode.style.letterSpacing = this._bareFontInfo.letterSpacing + 'px';
+		container.appendChild(regularDomNode);
+
+		let boldDomNode = document.createElement('div');
+		boldDomNode.style.fontFamily = this._bareFontInfo.fontFamily;
+		boldDomNode.style.fontWeight = 'bold';
+		boldDomNode.style.fontSize = this._bareFontInfo.fontSize + 'px';
+		boldDomNode.style.lineHeight = this._bareFontInfo.lineHeight + 'px';
+		boldDomNode.style.letterSpacing = this._bareFontInfo.letterSpacing + 'px';
+		container.appendChild(boldDomNode);
+
+		let italicDomNode = document.createElement('div');
+		italicDomNode.style.fontFamily = this._bareFontInfo.fontFamily;
+		italicDomNode.style.fontWeight = this._bareFontInfo.fontWeight;
+		italicDomNode.style.fontSize = this._bareFontInfo.fontSize + 'px';
+		italicDomNode.style.lineHeight = this._bareFontInfo.lineHeight + 'px';
+		italicDomNode.style.letterSpacing = this._bareFontInfo.letterSpacing + 'px';
+		italicDomNode.style.fontStyle = 'italic';
+		container.appendChild(italicDomNode);
+
+		let testElements: HTMLSpanElement[] = [];
+		for (let i = 0, len = this._requests.length; i < len; i++) {
+			const request = this._requests[i];
+
+			let parent: HTMLElement;
+			if (request.type === CharWidthRequestType.Regular) {
+				parent = regularDomNode;
+			}
+			if (request.type === CharWidthRequestType.Bold) {
+				parent = boldDomNode;
+			}
+			if (request.type === CharWidthRequestType.Italic) {
+				parent = italicDomNode;
+			}
+
+			parent.appendChild(document.createElement('br'));
+
+			let testElement = document.createElement('span');
+			DomCharWidthReader._render(testElement, request);
+			parent.appendChild(testElement);
+
+			testElements[i] = testElement;
+		}
+
+		this._container = container;
+		this._testElements = testElements;
+	}
+
+	private static _render(testElement: HTMLElement, request: CharWidthRequest): void {
+		if (request.chr === ' ') {
+			let htmlString = '&nbsp;';
+			// Repeat character 256 (2^8) times
+			for (let i = 0; i < 8; i++) {
+				htmlString += htmlString;
+			}
+			testElement.innerHTML = htmlString;
+		} else {
+			let testString = request.chr;
+			// Repeat character 256 (2^8) times
+			for (let i = 0; i < 8; i++) {
+				testString += testString;
+			}
+			testElement.textContent = testString;
+		}
+	}
+
+	private _readFromDomElements(): void {
+		for (let i = 0, len = this._requests.length; i < len; i++) {
+			const request = this._requests[i];
+			const testElement = this._testElements[i];
+
+			request.fulfill(testElement.offsetWidth / 256);
+		}
+	}
+}
+
+export function readCharWidths(bareFontInfo: BareFontInfo, requests: CharWidthRequest[]): void {
+	let reader = new DomCharWidthReader(bareFontInfo, requests);
+	reader.read();
+}