Make terminal rendering work in popout windows

Add support for the parent element (what is passed to Terminal.open)
being in a different (same origin) window. Accesses to DOM APIs such
as requestAnimationFrame and devicePixelRatio thus need to be scoped
to the corrent window, instead of assuming that it's the same as the
window/global scope where the code is running.

This is done by inferring a parent window at the creation time, and
then storing it in CoreBrowserService, which is already passed to most
places that need it.

To catch future regressions, an ESLint rule that checks for global
accesses is added (it uses AST selectors via the no-restricted-syntax
rule).

This should also be applicable when the parent element is an iframe.

Fixes #3758

addons/xterm-addon-webgl/src/WebglRenderer.ts

@@ -77,7 +77,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
     this._core = (this._terminal as any)._core;
 
     this._renderLayers = [
-      new LinkRenderLayer(this._core.screenElement!, 2, this._colors, this._core),
+      new LinkRenderLayer(this._core.screenElement!, 2, this._colors, this._core, this._coreBrowserService),
       new CursorRenderLayer(_terminal, this._core.screenElement!, 3, this._colors, this._onRequestRedraw, this._coreBrowserService, coreService)
     ];
     this.dimensions = {
@@ -94,7 +94,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
       actualCellWidth: 0,
       actualCellHeight: 0
     };
-    this._devicePixelRatio = window.devicePixelRatio;
+    this._devicePixelRatio = this._coreBrowserService.dpr;
     this._updateDimensions();
 
     this._canvas = document.createElement('canvas');
@@ -132,13 +132,13 @@ export class WebglRenderer extends Disposable implements IRenderer {
       this._requestRedrawViewport();
     }));
 
-    this.register(observeDevicePixelDimensions(this._canvas, (w, h) => this._setCanvasDevicePixelDimensions(w, h)));
+    this.register(observeDevicePixelDimensions(this._canvas, this._coreBrowserService.window, (w, h) => this._setCanvasDevicePixelDimensions(w, h)));
 
     this._core.screenElement!.appendChild(this._canvas);
 
     this._initializeWebGLState();
 
-    this._isAttached = document.body.contains(this._core.screenElement!);
+    this._isAttached = this._coreBrowserService.window.document.body.contains(this._core.screenElement!);
   }
 
   public dispose(): void {
@@ -173,8 +173,8 @@ export class WebglRenderer extends Disposable implements IRenderer {
   public onDevicePixelRatioChange(): void {
     // If the device pixel ratio changed, the char atlas needs to be regenerated
     // and the terminal needs to refreshed
-    if (this._devicePixelRatio !== window.devicePixelRatio) {
-      this._devicePixelRatio = window.devicePixelRatio;
+    if (this._devicePixelRatio !== this._coreBrowserService.dpr) {
+      this._devicePixelRatio = this._coreBrowserService.dpr;
       this.onResize(this._terminal.cols, this._terminal.rows);
     }
   }
@@ -281,7 +281,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
       return;
     }
 
-    const atlas = acquireCharAtlas(this._terminal, this._colors, this.dimensions.scaledCellWidth, this.dimensions.scaledCellHeight, this.dimensions.scaledCharWidth, this.dimensions.scaledCharHeight);
+    const atlas = acquireCharAtlas(this._terminal, this._colors, this.dimensions.scaledCellWidth, this.dimensions.scaledCellHeight, this.dimensions.scaledCharWidth, this.dimensions.scaledCharHeight, this._coreBrowserService.dpr);
     if (!('getRasterizedGlyph' in atlas)) {
       throw new Error('The webgl renderer only works with the webgl char atlas');
     }
@@ -329,7 +329,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
 
   public renderRows(start: number, end: number): void {
     if (!this._isAttached) {
-      if (document.body.contains(this._core.screenElement!) && (this._core as any)._charSizeService.width && (this._core as any)._charSizeService.height) {
+      if (this._coreBrowserService.window.document.body.contains(this._core.screenElement!) && (this._core as any)._charSizeService.width && (this._core as any)._charSizeService.height) {
         this._updateDimensions();
         this._refreshCharAtlas();
         this._isAttached = true;

addons/xterm-addon-webgl/src/atlas/CharAtlasCache.ts

@@ -31,9 +31,10 @@ export function acquireCharAtlas(
   scaledCellWidth: number,
   scaledCellHeight: number,
   scaledCharWidth: number,
-  scaledCharHeight: number
+  scaledCharHeight: number,
+  devicePixelRatio: number
 ): WebglCharAtlas {
-  const newConfig = generateConfig(scaledCellWidth, scaledCellHeight, scaledCharWidth, scaledCharHeight, terminal, colors);
+  const newConfig = generateConfig(scaledCellWidth, scaledCellHeight, scaledCharWidth, scaledCharHeight, terminal, colors, devicePixelRatio);
 
   // Check to see if the terminal already owns this config
   for (let i = 0; i < charAtlasCache.length; i++) {

addons/xterm-addon-webgl/src/atlas/CharAtlasUtils.ts

@@ -14,7 +14,7 @@ const NULL_COLOR: IColor = {
   rgba: 0
 };
 
-export function generateConfig(scaledCellWidth: number, scaledCellHeight: number, scaledCharWidth: number, scaledCharHeight: number, terminal: Terminal, colors: IColorSet): ICharAtlasConfig {
+export function generateConfig(scaledCellWidth: number, scaledCellHeight: number, scaledCharWidth: number, scaledCharHeight: number, terminal: Terminal, colors: IColorSet, devicePixelRatio: number): ICharAtlasConfig {
   // null out some fields that don't matter
   const clonedColors: IColorSet = {
     foreground: colors.foreground,
@@ -33,7 +33,7 @@ export function generateConfig(scaledCellWidth: number, scaledCellHeight: number
   };
   return {
     customGlyphs: terminal.options.customGlyphs,
-    devicePixelRatio: window.devicePixelRatio,
+    devicePixelRatio,
     letterSpacing: terminal.options.letterSpacing,
     lineHeight: terminal.options.lineHeight,
     scaledCellWidth,

addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts

@@ -409,7 +409,7 @@ export class WebglCharAtlas implements IDisposable {
     // Draw custom characters if applicable
     let customGlyph = false;
     if (this._config.customGlyphs !== false) {
-      customGlyph = tryDrawCustomChar(this._tmpCtx, chars, padding, padding, this._config.scaledCellWidth, this._config.scaledCellHeight, this._config.fontSize);
+      customGlyph = tryDrawCustomChar(this._tmpCtx, chars, padding, padding, this._config.scaledCellWidth, this._config.scaledCellHeight, this._config.fontSize, this._config.devicePixelRatio);
     }
 
     // Whether to clear pixels based on a threshold difference between the glyph color and the
@@ -427,7 +427,7 @@ export class WebglCharAtlas implements IDisposable {
     // Draw underline
     if (underline) {
       this._tmpCtx.save();
-      const lineWidth = Math.max(1, Math.floor(this._config.fontSize * window.devicePixelRatio / 15));
+      const lineWidth = Math.max(1, Math.floor(this._config.fontSize * this._config.devicePixelRatio / 15));
       // When the line width is odd, draw at a 0.5 position
       const yOffset = lineWidth % 2 === 1 ? 0.5 : 0;
       this._tmpCtx.lineWidth = lineWidth;
@@ -501,12 +501,12 @@ export class WebglCharAtlas implements IDisposable {
             );
             break;
           case UnderlineStyle.DOTTED:
-            this._tmpCtx.setLineDash([window.devicePixelRatio * 2, window.devicePixelRatio]);
+            this._tmpCtx.setLineDash([this._config.devicePixelRatio * 2, this._config.devicePixelRatio]);
             this._tmpCtx.moveTo(xChLeft, yTop);
             this._tmpCtx.lineTo(xChRight, yTop);
             break;
           case UnderlineStyle.DASHED:
-            this._tmpCtx.setLineDash([window.devicePixelRatio * 4, window.devicePixelRatio * 3]);
+            this._tmpCtx.setLineDash([this._config.devicePixelRatio * 4, this._config.devicePixelRatio * 3]);
             this._tmpCtx.moveTo(xChLeft, yTop);
             this._tmpCtx.lineTo(xChRight, yTop);
             break;
@@ -543,7 +543,7 @@ export class WebglCharAtlas implements IDisposable {
             const clipRegion = new Path2D();
             clipRegion.rect(xLeft, yTop - Math.ceil(lineWidth / 2), this._config.scaledCellWidth, yBot - yTop + Math.ceil(lineWidth / 2));
             this._tmpCtx.clip(clipRegion);
-            this._tmpCtx.lineWidth = window.devicePixelRatio * 3;
+            this._tmpCtx.lineWidth = this._config.devicePixelRatio * 3;
             this._tmpCtx.strokeStyle = backgroundColor.css;
             this._tmpCtx.strokeText(chars, padding, padding + this._config.scaledCharHeight);
             this._tmpCtx.restore();
@@ -578,7 +578,7 @@ export class WebglCharAtlas implements IDisposable {
 
     // Draw strokethrough
     if (strikethrough) {
-      const lineWidth = Math.max(1, Math.floor(this._config.fontSize * window.devicePixelRatio / 10));
+      const lineWidth = Math.max(1, Math.floor(this._config.fontSize * this._config.devicePixelRatio / 10));
       const yOffset = this._tmpCtx.lineWidth % 2 === 1 ? 0.5 : 0; // When the width is odd, draw at 0.5 position
       this._tmpCtx.lineWidth = lineWidth;
       this._tmpCtx.strokeStyle = this._tmpCtx.fillStyle;

addons/xterm-addon-webgl/src/renderLayer/BaseRenderLayer.ts

@@ -8,6 +8,7 @@ import { acquireCharAtlas } from '../atlas/CharAtlasCache';
 import { Terminal } from 'xterm';
 import { IColorSet } from 'browser/Types';
 import { TEXT_BASELINE } from 'browser/renderer/Constants';
+import { ICoreBrowserService } from 'browser/services/Services';
 import { IRenderDimensions } from 'browser/renderer/Types';
 import { CellData } from 'common/buffer/CellData';
 import { WebglCharAtlas } from 'atlas/WebglCharAtlas';
@@ -30,7 +31,8 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     id: string,
     zIndex: number,
     private _alpha: boolean,
-    protected _colors: IColorSet
+    protected _colors: IColorSet,
+    protected readonly _coreBrowserService: ICoreBrowserService
   ) {
     this._canvas = document.createElement('canvas');
     this._canvas.classList.add(`xterm-${id}-layer`);
@@ -93,7 +95,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     if (this._scaledCharWidth <= 0 && this._scaledCharHeight <= 0) {
       return;
     }
-    this._charAtlas = acquireCharAtlas(terminal, colorSet, this._scaledCellWidth, this._scaledCellHeight, this._scaledCharWidth, this._scaledCharHeight);
+    this._charAtlas = acquireCharAtlas(terminal, colorSet, this._scaledCellWidth, this._scaledCellHeight, this._scaledCharWidth, this._scaledCharHeight, this._coreBrowserService.dpr);
     this._charAtlas.warmUp();
   }
 
@@ -143,9 +145,9 @@ export abstract class BaseRenderLayer implements IRenderLayer {
   protected _fillBottomLineAtCells(x: number, y: number, width: number = 1): void {
     this._ctx.fillRect(
       x * this._scaledCellWidth,
-      (y + 1) * this._scaledCellHeight - window.devicePixelRatio - 1 /* Ensure it's drawn within the cell */,
+      (y + 1) * this._scaledCellHeight - this._coreBrowserService.dpr - 1 /* Ensure it's drawn within the cell */,
       width * this._scaledCellWidth,
-      window.devicePixelRatio);
+      this._coreBrowserService.dpr);
   }
 
   /**
@@ -158,7 +160,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     this._ctx.fillRect(
       x * this._scaledCellWidth,
       y * this._scaledCellHeight,
-      window.devicePixelRatio * width,
+      this._coreBrowserService.dpr * width,
       this._scaledCellHeight);
   }
 
@@ -169,12 +171,12 @@ export abstract class BaseRenderLayer implements IRenderLayer {
    * @param y The row to fill.
    */
   protected _strokeRectAtCell(x: number, y: number, width: number, height: number): void {
-    this._ctx.lineWidth = window.devicePixelRatio;
+    this._ctx.lineWidth = this._coreBrowserService.dpr;
     this._ctx.strokeRect(
-      x * this._scaledCellWidth + window.devicePixelRatio / 2,
-      y * this._scaledCellHeight + (window.devicePixelRatio / 2),
-      width * this._scaledCellWidth - window.devicePixelRatio,
-      (height * this._scaledCellHeight) - window.devicePixelRatio);
+      x * this._scaledCellWidth + this._coreBrowserService.dpr / 2,
+      y * this._scaledCellHeight + (this._coreBrowserService.dpr / 2),
+      width * this._scaledCellWidth - this._coreBrowserService.dpr,
+      (height * this._scaledCellHeight) - this._coreBrowserService.dpr);
   }
 
   /**
@@ -258,7 +260,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
     const fontWeight = isBold ? terminal.options.fontWeightBold : terminal.options.fontWeight;
     const fontStyle = isItalic ? 'italic' : '';
 
-    return `${fontStyle} ${fontWeight} ${terminal.options.fontSize! * window.devicePixelRatio}px ${terminal.options.fontFamily}`;
+    return `${fontStyle} ${fontWeight} ${terminal.options.fontSize! * this._coreBrowserService.dpr}px ${terminal.options.fontFamily}`;
   }
 }
 

addons/xterm-addon-webgl/src/renderLayer/CursorRenderLayer.ts

@@ -38,10 +38,10 @@ export class CursorRenderLayer extends BaseRenderLayer {
     zIndex: number,
     colors: IColorSet,
     private _onRequestRefreshRowsEvent: IEventEmitter<IRequestRedrawEvent>,
-    private readonly _coreBrowserService: ICoreBrowserService,
+    coreBrowserService: ICoreBrowserService,
     private readonly _coreService: ICoreService
   ) {
-    super(container, 'cursor', zIndex, true, colors);
+    super(container, 'cursor', zIndex, true, colors, coreBrowserService);
     this._state = {
       x: 0,
       y: 0,
@@ -195,7 +195,7 @@ export class CursorRenderLayer extends BaseRenderLayer {
   private _clearCursor(): void {
     if (this._state) {
       // Avoid potential rounding errors when device pixel ratio is less than 1
-      if (window.devicePixelRatio < 1) {
+      if (this._coreBrowserService.dpr < 1) {
         this._clearAll();
       } else {
         this._clearCells(this._state.x, this._state.y, this._state.width, 1);
@@ -257,10 +257,10 @@ class CursorBlinkStateManager {
 
   constructor(
     private _renderCallback: () => void,
-    coreBrowserService: ICoreBrowserService
+    private _coreBrowserService: ICoreBrowserService
   ) {
     this.isCursorVisible = true;
-    if (coreBrowserService.isFocused) {
+    if (this._coreBrowserService.isFocused) {
       this._restartInterval();
     }
   }
@@ -269,15 +269,15 @@ class CursorBlinkStateManager {
 
   public dispose(): void {
     if (this._blinkInterval) {
-      window.clearInterval(this._blinkInterval);
+      this._coreBrowserService.window.clearInterval(this._blinkInterval);
       this._blinkInterval = undefined;
     }
     if (this._blinkStartTimeout) {
-      window.clearTimeout(this._blinkStartTimeout);
+      this._coreBrowserService.window.clearTimeout(this._blinkStartTimeout);
       this._blinkStartTimeout = undefined;
     }
     if (this._animationFrame) {
-      window.cancelAnimationFrame(this._animationFrame);
+      this._coreBrowserService.window.cancelAnimationFrame(this._animationFrame);
       this._animationFrame = undefined;
     }
   }
@@ -291,7 +291,7 @@ class CursorBlinkStateManager {
     // Force a cursor render to ensure it's visible and in the correct position
     this.isCursorVisible = true;
     if (!this._animationFrame) {
-      this._animationFrame = window.requestAnimationFrame(() => {
+      this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
         this._renderCallback();
         this._animationFrame = undefined;
       });
@@ -301,7 +301,7 @@ class CursorBlinkStateManager {
   private _restartInterval(timeToStart: number = BLINK_INTERVAL): void {
     // Clear any existing interval
     if (this._blinkInterval) {
-      window.clearInterval(this._blinkInterval);
+      this._coreBrowserService.window.clearInterval(this._blinkInterval);
       this._blinkInterval = undefined;
     }
 
@@ -309,7 +309,7 @@ class CursorBlinkStateManager {
     // the regular interval is setup in order to support restarting the blink
     // animation in a lightweight way (without thrashing clearInterval and
     // setInterval).
-    this._blinkStartTimeout = window.setTimeout(() => {
+    this._blinkStartTimeout = this._coreBrowserService.window.setTimeout(() => {
       // Check if another animation restart was requested while this was being
       // started
       if (this._animationTimeRestarted) {
@@ -323,13 +323,13 @@ class CursorBlinkStateManager {
 
       // Hide the cursor
       this.isCursorVisible = false;
-      this._animationFrame = window.requestAnimationFrame(() => {
+      this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
         this._renderCallback();
         this._animationFrame = undefined;
       });
 
       // Setup the blink interval
-      this._blinkInterval = window.setInterval(() => {
+      this._blinkInterval = this._coreBrowserService.window.setInterval(() => {
         // Adjust the animation time if it was restarted
         if (this._animationTimeRestarted) {
           // calc time diff
@@ -342,7 +342,7 @@ class CursorBlinkStateManager {
 
         // Invert visibility and render
         this.isCursorVisible = !this.isCursorVisible;
-        this._animationFrame = window.requestAnimationFrame(() => {
+        this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => {
           this._renderCallback();
           this._animationFrame = undefined;
         });
@@ -353,15 +353,15 @@ class CursorBlinkStateManager {
   public pause(): void {
     this.isCursorVisible = true;
     if (this._blinkInterval) {
-      window.clearInterval(this._blinkInterval);
+      this._coreBrowserService.window.clearInterval(this._blinkInterval);
       this._blinkInterval = undefined;
     }
     if (this._blinkStartTimeout) {
-      window.clearTimeout(this._blinkStartTimeout);
+      this._coreBrowserService.window.clearTimeout(this._blinkStartTimeout);
       this._blinkStartTimeout = undefined;
     }
     if (this._animationFrame) {
-      window.cancelAnimationFrame(this._animationFrame);
+      this._coreBrowserService.window.cancelAnimationFrame(this._animationFrame);
       this._animationFrame = undefined;
     }
   }

addons/xterm-addon-webgl/src/renderLayer/LinkRenderLayer.ts

@@ -9,12 +9,19 @@ import { INVERTED_DEFAULT_COLOR } from 'browser/renderer/Constants';
 import { is256Color } from '../atlas/CharAtlasUtils';
 import { ITerminal, IColorSet, ILinkifierEvent } from 'browser/Types';
 import { IRenderDimensions } from 'browser/renderer/Types';
+import { ICoreBrowserService } from 'browser/services/Services';
 
 export class LinkRenderLayer extends BaseRenderLayer {
   private _state: ILinkifierEvent | undefined;
 
-  constructor(container: HTMLElement, zIndex: number, colors: IColorSet, terminal: ITerminal) {
-    super(container, 'link', zIndex, true, colors);
+  constructor(
+    container: HTMLElement,
+    zIndex: number,
+    colors: IColorSet,
+    terminal: ITerminal,
+    coreBrowserService: ICoreBrowserService
+  ) {
+    super(container, 'link', zIndex, true, colors, coreBrowserService);
 
     terminal.linkifier2.onShowLinkUnderline(e => this._onShowLinkUnderline(e));
     terminal.linkifier2.onHideLinkUnderline(e => this._onHideLinkUnderline(e));