Remove canvas char atlas base class

addons/xterm-addon-canvas/src/BaseRenderLayer.ts

@@ -9,7 +9,6 @@ import { ICellData, IColor } from 'common/Types';
 import { DEFAULT_COLOR, WHITESPACE_CELL_CHAR, WHITESPACE_CELL_CODE, Attributes } from 'common/buffer/Constants';
 import { IGlyphIdentifier } from './atlas/Types';
 import { DIM_OPACITY, INVERTED_DEFAULT_COLOR, TEXT_BASELINE } from 'browser/renderer/shared/Constants';
-import { BaseCharAtlas } from './atlas/BaseCharAtlas';
 import { acquireCharAtlas } from './atlas/CharAtlasCache';
 import { AttributeData } from 'common/buffer/AttributeData';
 import { IColorSet } from 'browser/Types';
@@ -21,6 +20,7 @@ import { channels, color, rgba } from 'common/Color';
 import { removeElementFromParent } from 'browser/Dom';
 import { tryDrawCustomChar } from 'browser/renderer/shared/CustomGlyphs';
 import { Terminal } from 'xterm';
+import { DynamicCharAtlas } from 'atlas/DynamicCharAtlas';
 
 export abstract class BaseRenderLayer implements IRenderLayer {
   private _canvas: HTMLCanvasElement;
@@ -36,7 +36,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
   protected _selectionEnd: [number, number] | undefined;
   protected _columnSelectMode: boolean = false;
 
-  protected _charAtlas: BaseCharAtlas | undefined;
+  protected _charAtlas: DynamicCharAtlas | undefined;
 
   /**
    * An object that's reused when drawing glyphs in order to reduce GC.

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

@@ -1,59 +0,0 @@
-/**
- * Copyright (c) 2017 The xterm.js authors. All rights reserved.
- * @license MIT
- */
-
-import { IGlyphIdentifier } from './Types';
-import { IDisposable } from 'common/Types';
-
-export abstract class BaseCharAtlas implements IDisposable {
-  private _didWarmUp: boolean = false;
-  public abstract readonly cacheCanvas: HTMLCanvasElement;
-
-  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.
-   */
-  private _doWarmUp(): void { }
-
-  public clear(): 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-canvas/src/atlas/CharAtlasCache.ts

@@ -4,14 +4,13 @@
  */
 
 import { generateConfig, configEquals } from 'browser/renderer/shared/CharAtlasUtils';
-import { BaseCharAtlas } from './BaseCharAtlas';
 import { DynamicCharAtlas } from './DynamicCharAtlas';
 import { IColorSet } from 'browser/Types';
 import { Terminal } from 'xterm';
 import { ICharAtlasConfig } from 'browser/renderer/shared/Types';
 
 interface ICharAtlasCacheEntry {
-  atlas: BaseCharAtlas;
+  atlas: DynamicCharAtlas;
   config: ICharAtlasConfig;
   // N.B. This implementation potentially holds onto copies of the terminal forever, so
   // this may cause memory leaks.
@@ -32,7 +31,7 @@ export function acquireCharAtlas(
   scaledCharWidth: number,
   scaledCharHeight: number,
   devicePixelRatio: number
-): BaseCharAtlas {
+): DynamicCharAtlas {
   const newConfig = generateConfig(scaledCellWidth, scaledCellHeight, scaledCharWidth, scaledCharHeight, terminal, colors, devicePixelRatio);
 
   // Check to see if the renderer already owns this config

addons/xterm-addon-canvas/src/atlas/DynamicCharAtlas.ts

@@ -5,7 +5,6 @@
 
 import { DIM_OPACITY, INVERTED_DEFAULT_COLOR, TEXT_BASELINE } from 'browser/renderer/shared/Constants';
 import { IGlyphIdentifier } from './Types';
-import { BaseCharAtlas } from './BaseCharAtlas';
 import { DEFAULT_ANSI_COLORS } from 'browser/ColorManager';
 import { LRUMap } from './LRUMap';
 import { isFirefox, isSafari } from 'common/Platform';
@@ -52,14 +51,16 @@ export function getGlyphCacheKey(glyph: IGlyphIdentifier): number {
   return glyph.code << 21 | glyph.bg << 12 | glyph.fg << 3 | (glyph.bold ? 0 : 4) + (glyph.dim ? 0 : 2) + (glyph.italic ? 0 : 1);
 }
 
-export class DynamicCharAtlas extends BaseCharAtlas {
+export class DynamicCharAtlas {
   // An ordered map that we're using to keep track of where each glyph is in the atlas texture.
   // It's ordered so that we can determine when to remove the old entries.
   private _cacheMap: LRUMap<IGlyphCacheValue>;
 
   // The texture that the atlas is drawn to
   private _cacheCanvas: HTMLCanvasElement;
+  public get cacheCanvas(): HTMLCanvasElement { return this._cacheCanvas; }
   private _cacheCtx: CanvasRenderingContext2D;
+  private _didWarmUp: boolean = false;
 
   // A temporary context that glyphs are drawn to before being transfered to the atlas.
   private _tmpCtx: CanvasRenderingContext2D;
@@ -80,7 +81,6 @@ export class DynamicCharAtlas extends BaseCharAtlas {
   private _bitmap: ImageBitmap | null = null;
 
   constructor(document: Document, private _config: ICharAtlasConfig) {
-    super();
     this._cacheCanvas = document.createElement('canvas');
     this._cacheCanvas.width = TEXTURE_WIDTH;
     this._cacheCanvas.height = TEXTURE_HEIGHT;
@@ -111,10 +111,23 @@ export class DynamicCharAtlas extends BaseCharAtlas {
     }
   }
 
-  public override get cacheCanvas(): HTMLCanvasElement {
-    return this._cacheCanvas!;
+  /**
+   * 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.
+   */
+  private _doWarmUp(): void { }
+
   public beginFrame(): void {
     this._drawToCacheCount = 0;
   }
@@ -371,27 +384,6 @@ export class DynamicCharAtlas extends BaseCharAtlas {
   }
 }
 
-// This is used for debugging the renderer, just swap out `new DynamicCharAtlas` with
-// `new NoneCharAtlas`.
-export class NoneCharAtlas extends BaseCharAtlas {
-  constructor(document: Document, config: ICharAtlasConfig) {
-    super();
-  }
-
-  public override get cacheCanvas(): HTMLCanvasElement {
-    return null!;
-  }
-
-  public draw(
-    ctx: CanvasRenderingContext2D,
-    glyph: IGlyphIdentifier,
-    x: number,
-    y: number
-  ): boolean {
-    return false;
-  }
-}
-
 /**
  * Makes a particular rgb color and colors that are nearly the same in an ImageData completely
  * transparent.