Handle glyph widths up to the maximum device texture size

addons/addon-webgl/src/WebglRenderer.ts

@@ -33,6 +33,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
   private _charAtlasDisposable = this._register(new MutableDisposable());
   private _charAtlas: ITextureAtlas | undefined;
   private _devicePixelRatio: number;
+  private _deviceMaxTextureSize: number;
   private _observerDisposable = this._register(new MutableDisposable());
 
   private _model: RenderModel = new RenderModel();
@@ -102,6 +103,8 @@ export class WebglRenderer extends Disposable implements IRenderer {
       throw new Error('WebGL2 not supported ' + this._gl);
     }
 
+    this._deviceMaxTextureSize = this._gl.getParameter(this._gl.MAX_TEXTURE_SIZE);
+
     this._register(addDisposableListener(this._canvas, 'webglcontextlost', (e) => {
       console.log('webglcontextlost event received');
       // Prevent the default behavior in order to enable WebGL context restoration.
@@ -272,7 +275,8 @@ export class WebglRenderer extends Disposable implements IRenderer {
       this.dimensions.device.cell.height,
       this.dimensions.device.char.width,
       this.dimensions.device.char.height,
-      this._coreBrowserService.dpr
+      this._coreBrowserService.dpr,
+      this._deviceMaxTextureSize
     );
     if (this._charAtlas !== atlas) {
       this._onChangeTextureAtlas.fire(atlas.pages[0].canvas);

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

@@ -94,7 +94,8 @@ export abstract class BaseRenderLayer extends Disposable implements IRenderLayer
     if (this._deviceCharWidth <= 0 && this._deviceCharHeight <= 0) {
       return;
     }
-    this._charAtlas = acquireTextureAtlas(terminal, this._optionsService.rawOptions, colorSet, this._deviceCellWidth, this._deviceCellHeight, this._deviceCharWidth, this._deviceCharHeight, this._coreBrowserService.dpr);
+
+    this._charAtlas = acquireTextureAtlas(terminal, this._optionsService.rawOptions, colorSet, this._deviceCellWidth, this._deviceCellHeight, this._deviceCharWidth, this._deviceCharHeight, this._coreBrowserService.dpr, 2048);
     this._charAtlas.warmUp();
   }
 

src/browser/renderer/shared/CharAtlasCache.ts

@@ -31,9 +31,10 @@ export function acquireTextureAtlas(
   deviceCellHeight: number,
   deviceCharWidth: number,
   deviceCharHeight: number,
-  devicePixelRatio: number
+  devicePixelRatio: number,
+  deviceMaxTextureSize: number
 ): ITextureAtlas {
-  const newConfig = generateConfig(deviceCellWidth, deviceCellHeight, deviceCharWidth, deviceCharHeight, options, colors, devicePixelRatio);
+  const newConfig = generateConfig(deviceCellWidth, deviceCellHeight, deviceCharWidth, deviceCharHeight, options, colors, devicePixelRatio, deviceMaxTextureSize);
 
   // Check to see if the terminal already owns this config
   for (let i = 0; i < charAtlasCache.length; i++) {

src/browser/renderer/shared/CharAtlasUtils.ts

@@ -9,7 +9,7 @@ import { ITerminalOptions } from '@xterm/xterm';
 import { IColorSet, ReadonlyColorSet } from 'browser/Types';
 import { NULL_COLOR } from 'common/Color';
 
-export function generateConfig(deviceCellWidth: number, deviceCellHeight: number, deviceCharWidth: number, deviceCharHeight: number, options: Required<ITerminalOptions>, colors: ReadonlyColorSet, devicePixelRatio: number): ICharAtlasConfig {
+export function generateConfig(deviceCellWidth: number, deviceCellHeight: number, deviceCharWidth: number, deviceCharHeight: number, options: Required<ITerminalOptions>, colors: ReadonlyColorSet, devicePixelRatio: number, deviceMaxTextureSize: number): ICharAtlasConfig {
   // null out some fields that don't matter
   const clonedColors: IColorSet = {
     foreground: colors.foreground,
@@ -34,6 +34,7 @@ export function generateConfig(deviceCellWidth: number, deviceCellHeight: number
   return {
     customGlyphs: options.customGlyphs,
     devicePixelRatio,
+    deviceMaxTextureSize,
     letterSpacing: options.letterSpacing,
     lineHeight: options.lineHeight,
     deviceCellWidth: deviceCellWidth,

src/browser/renderer/shared/TextureAtlas.ts

@@ -66,6 +66,7 @@ export class TextureAtlas implements ITextureAtlas {
 
   // The set of atlas pages that can be written to
   private _activePages: AtlasPage[] = [];
+  private _overflowSizePage: AtlasPage | undefined;
 
   private _tmpCanvas: HTMLCanvasElement;
   // A temporary context that glyphs are drawn to before being transfered to the atlas.
@@ -431,7 +432,7 @@ export class TextureAtlas implements ITextureAtlas {
     // Allow 1 cell width per character, with a minimum of 2 (CJK), plus some padding. This is used
     // to draw the glyph to the canvas as well as to restrict the bounding box search to ensure
     // giant ligatures (eg. =====>) don't impact overall performance.
-    const allowedWidth = Math.min(this._config.deviceCellWidth * Math.max(chars.length, 2) + TMP_CANVAS_GLYPH_PADDING * 2, this._textureSize);
+    const allowedWidth = Math.min(this._config.deviceCellWidth * Math.max(chars.length, 2) + TMP_CANVAS_GLYPH_PADDING * 2, this._config.deviceMaxTextureSize);
     if (this._tmpCanvas.width < allowedWidth) {
       this._tmpCanvas.width = allowedWidth;
     }
@@ -772,6 +773,27 @@ export class TextureAtlas implements ITextureAtlas {
         }
       }
 
+      // Create a new page for oversized glyphs as they come up
+      if (rasterizedGlyph.size.x > this._textureSize) {
+        if (!this._overflowSizePage) {
+          this._overflowSizePage = new AtlasPage(this._document, this._config.deviceMaxTextureSize);
+          this.pages.push(this._overflowSizePage);
+
+          // Request the model to be cleared to refresh all texture pages.
+          this._requestClearModel = true;
+          this._onAddTextureAtlasCanvas.fire(this._overflowSizePage.canvas);
+        }
+        activePage = this._overflowSizePage;
+        activeRow = this._overflowSizePage.currentRow;
+        // Move to next row if necessary
+        if (activeRow.x + rasterizedGlyph.size.x >= activePage.canvas.width) {
+          activeRow.x = 0;
+          activeRow.y += activeRow.height;
+          activeRow.height = 0;
+        }
+        break;
+      }
+
       // Create a new page if too much vertical space would be wasted or there is not enough room
       // left in the page. The previous active row will become fixed in the process as it now has a
       // fixed height
@@ -782,6 +804,7 @@ export class TextureAtlas implements ITextureAtlas {
         if (activePage.currentRow.y + activePage.currentRow.height + rasterizedGlyph.size.y >= activePage.canvas.height) {
           // Find the first page with room to create the new row on
           let candidatePage: AtlasPage | undefined;
+
           for (const p of this._activePages) {
             if (p.currentRow.y + p.currentRow.height + rasterizedGlyph.size.y < p.canvas.height) {
               candidatePage = p;

src/browser/renderer/shared/Types.ts

@@ -11,6 +11,7 @@ import type { Event } from 'vs/base/common/event';
 export interface ICharAtlasConfig {
   customGlyphs: boolean;
   devicePixelRatio: number;
+  deviceMaxTextureSize: number;
   letterSpacing: number;
   lineHeight: number;
   fontSize: number;