Simplify webgl atlas by removing BaseCharAtlas

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

@@ -1,56 +0,0 @@
-/**
- * Copyright (c) 2017 The xterm.js authors. All rights reserved.
- * @license MIT
- */
-
-import { IGlyphIdentifier } from './Types';
-import { IDisposable } from 'xterm';
-
-export abstract class BaseCharAtlas implements IDisposable {
-  private _didWarmUp: boolean = false;
-
-  public dispose(): void { }
-
-  /**
-   * Perform any work needed to warm the cache before it can be used. May be called multiple times.
-   * Implement _doWarmUp instead if you only want to get called once.
-   */
-  public warmUp(): void {
-    if (!this._didWarmUp) {
-      this._doWarmUp();
-      this._didWarmUp = true;
-    }
-  }
-
-  /**
-   * Perform any work needed to warm the cache before it can be used. Used by the default
-   * implementation of warmUp(), and will only be called once.
-   */
-  protected _doWarmUp(): void { }
-
-  /**
-   * Called when we start drawing a new frame.
-   *
-   * TODO: We rely on this getting called by TextRenderLayer. This should really be called by
-   * Renderer instead, but we need to make Renderer the source-of-truth for the char atlas, instead
-   * of BaseRenderLayer.
-   */
-  public beginFrame(): void { }
-
-  /**
-   * May be called before warmUp finishes, however it is okay for the implementation to
-   * do nothing and return false in that case.
-   *
-   * @param ctx Where to draw the character onto.
-   * @param glyph Information about what to draw
-   * @param x The position on the context to start drawing at
-   * @param y The position on the context to start drawing at
-   * @returns The success state. True if we drew the character.
-   */
-  public abstract draw(
-    ctx: CanvasRenderingContext2D,
-    glyph: IGlyphIdentifier,
-    x: number,
-    y: number
-  ): boolean;
-}

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

@@ -4,14 +4,13 @@
  */
 
 import { generateConfig, configEquals } from './CharAtlasUtils';
-import { BaseCharAtlas } from './BaseCharAtlas';
 import { WebglCharAtlas } from './WebglCharAtlas';
 import { ICharAtlasConfig } from './Types';
 import { Terminal } from 'xterm';
 import { IColorSet } from 'browser/Types';
 
 interface ICharAtlasCacheEntry {
-  atlas: BaseCharAtlas;
+  atlas: WebglCharAtlas;
   config: ICharAtlasConfig;
   // N.B. This implementation potentially holds onto copies of the terminal forever, so
   // this may cause memory leaks.
@@ -31,7 +30,7 @@ export function acquireCharAtlas(
   colors: IColorSet,
   scaledCharWidth: number,
   scaledCharHeight: number
-): BaseCharAtlas {
+): WebglCharAtlas {
   const newConfig = generateConfig(scaledCharWidth, scaledCharHeight, terminal, colors);
 
   // Check to see if the terminal already owns this config

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

@@ -3,14 +3,14 @@
  * @license MIT
  */
 
-import { IGlyphIdentifier, ICharAtlasConfig } from './Types';
+import { ICharAtlasConfig } from './Types';
 import { DIM_OPACITY, INVERTED_DEFAULT_COLOR } from 'browser/renderer/atlas/Constants';
-import { BaseCharAtlas } from './BaseCharAtlas';
 import { IRasterizedGlyph, IBoundingBox, IRasterizedGlyphSet } from '../Types';
 import { DEFAULT_COLOR, DEFAULT_ATTR } from 'common/buffer/Constants';
 import { is256Color } from './CharAtlasUtils';
 import { IColor } from 'browser/Types';
 import { FLAGS } from '../Constants';
+import { IDisposable } from 'xterm';
 
 // In practice we're probably never going to exhaust a texture this large. For debugging purposes,
 // however, it can be useful to set this to a really tiny value, to verify that LRU eviction works.
@@ -42,7 +42,9 @@ const NULL_RASTERIZED_GLYPH: IRasterizedGlyph = {
 
 const TMP_CANVAS_GLYPH_PADDING = 2;
 
-export class WebglCharAtlas extends BaseCharAtlas {
+export class WebglCharAtlas implements IDisposable {
+  private _didWarmUp: boolean = false;
+
   private _cacheMap: { [code: number]: IRasterizedGlyphSet } = {};
   private _cacheMapCombined: { [chars: string]: IRasterizedGlyphSet } = {};
 
@@ -67,8 +69,6 @@ export class WebglCharAtlas extends BaseCharAtlas {
   private _workBoundingBox: IBoundingBox = { top: 0, left: 0, bottom: 0, right: 0 };
 
   constructor(document: Document, private _config: ICharAtlasConfig) {
-    super();
-
     this.cacheCanvas = document.createElement('canvas');
     this.cacheCanvas.width = TEXTURE_WIDTH;
     this.cacheCanvas.height = TEXTURE_HEIGHT;
@@ -92,6 +92,13 @@ export class WebglCharAtlas extends BaseCharAtlas {
     }
   }
 
+  public warmUp(): void {
+    if (!this._didWarmUp) {
+      this._doWarmUp();
+      this._didWarmUp = true;
+    }
+  }
+
   protected _doWarmUp(): void {
     // Pre-fill with ASCII 33-126
     for (let i = 33; i < 126; i++) {
@@ -146,15 +153,6 @@ export class WebglCharAtlas extends BaseCharAtlas {
     return rasterizedGlyph;
   }
 
-  public draw(
-    ctx: CanvasRenderingContext2D,
-    glyph: IGlyphIdentifier,
-    x: number,
-    y: number
-  ): boolean {
-    throw new Error('WebglCharAtlas is only compatible with the webgl renderer');
-  }
-
   private _getColorFromAnsiIndex(idx: number): IColor {
     if (idx >= this._config.colors.ansi.length) {
       throw new Error('No color found for idx ' + idx);