Add ITextureAtlas and use that instead of WebglCharAtlas

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

@@ -4,13 +4,12 @@
  */
 
 import { createProgram, PROJECTION_MATRIX, throwIfFalsy } from './WebglUtils';
-import { WebglCharAtlas } from './atlas/WebglCharAtlas';
 import { IWebGL2RenderingContext, IWebGLVertexArrayObject, IRenderModel, IRasterizedGlyph } from './Types';
 import { fill } from 'common/TypedArrayUtils';
 import { NULL_CELL_CODE } from 'common/buffer/Constants';
 import { Terminal } from 'xterm';
 import { IColorSet } from 'browser/Types';
-import { IRenderDimensions } from 'browser/renderer/shared/Types';
+import { IRenderDimensions, ITextureAtlas } from 'browser/renderer/shared/Types';
 import { Disposable, toDisposable } from 'common/Lifecycle';
 
 interface IVertices {
@@ -77,7 +76,7 @@ let $leftCellPadding = 0;
 let $clippedPixels = 0;
 
 export class GlyphRenderer  extends Disposable {
-  private _atlas: WebglCharAtlas | undefined;
+  private _atlas: ITextureAtlas | undefined;
 
   private _program: WebGLProgram;
   private _vertexArrayObject: IWebGLVertexArrayObject;
@@ -321,7 +320,7 @@ export class GlyphRenderer  extends Disposable {
     gl.drawElementsInstanced(gl.TRIANGLES, 6, gl.UNSIGNED_BYTE, 0, bufferLength / INDICES_PER_CELL);
   }
 
-  public setAtlas(atlas: WebglCharAtlas): void {
+  public setAtlas(atlas: ITextureAtlas): void {
     const gl = this._gl;
     this._atlas = atlas;
 

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

@@ -7,7 +7,6 @@ import { GlyphRenderer } from './GlyphRenderer';
 import { LinkRenderLayer } from './renderLayer/LinkRenderLayer';
 import { CursorRenderLayer } from './renderLayer/CursorRenderLayer';
 import { acquireCharAtlas, removeTerminalFromCache } from './atlas/CharAtlasCache';
-import { WebglCharAtlas } from './atlas/WebglCharAtlas';
 import { RectangleRenderer } from './RectangleRenderer';
 import { IWebGL2RenderingContext } from './Types';
 import { RenderModel, COMBINED_CHAR_BIT_MASK, RENDER_MODEL_BG_OFFSET, RENDER_MODEL_FG_OFFSET, RENDER_MODEL_EXT_OFFSET, RENDER_MODEL_INDICIES_PER_CELL } from './RenderModel';
@@ -15,7 +14,7 @@ import { Disposable } from 'common/Lifecycle';
 import { Attributes, BgFlags, Content, FgFlags, NULL_CELL_CHAR, NULL_CELL_CODE } from 'common/buffer/Constants';
 import { Terminal, IEvent } from 'xterm';
 import { IRenderLayer } from './renderLayer/Types';
-import { IRenderDimensions, IRenderer, IRequestRedrawEvent } from 'browser/renderer/shared/Types';
+import { IRenderDimensions, IRenderer, IRequestRedrawEvent, ITextureAtlas } from 'browser/renderer/shared/Types';
 import { observeDevicePixelDimensions } from 'browser/renderer/shared/DevicePixelObserver';
 import { ITerminal, IColorSet } from 'browser/Types';
 import { EventEmitter } from 'common/EventEmitter';
@@ -35,7 +34,7 @@ let $isSelected = false;
 
 export class WebglRenderer extends Disposable implements IRenderer {
   private _renderLayers: IRenderLayer[];
-  private _charAtlas: WebglCharAtlas | undefined;
+  private _charAtlas: ITextureAtlas | undefined;
   private _devicePixelRatio: number;
 
   private _model: RenderModel = new RenderModel();

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

@@ -6,11 +6,11 @@
 import { WebglCharAtlas } from './WebglCharAtlas';
 import { Terminal } from 'xterm';
 import { IColorSet, ITerminal } from 'browser/Types';
-import { ICharAtlasConfig } from 'browser/renderer/shared/Types';
+import { ICharAtlasConfig, ITextureAtlas } from 'browser/renderer/shared/Types';
 import { generateConfig, configEquals } from 'browser/renderer/shared/CharAtlasUtils';
 
 interface ICharAtlasCacheEntry {
-  atlas: WebglCharAtlas;
+  atlas: ITextureAtlas;
   config: ICharAtlasConfig;
   // N.B. This implementation potentially holds onto copies of the terminal forever, so
   // this may cause memory leaks.
@@ -33,7 +33,7 @@ export function acquireCharAtlas(
   scaledCharWidth: number,
   scaledCharHeight: number,
   devicePixelRatio: number
-): WebglCharAtlas {
+): ITextureAtlas {
   const newConfig = generateConfig(scaledCellWidth, scaledCellHeight, scaledCharWidth, scaledCharHeight, terminal, colors, devicePixelRatio);
 
   // Check to see if the terminal already owns this config

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

@@ -16,7 +16,7 @@ import { excludeFromContrastRatioDemands, isPowerlineGlyph, isRestrictedPowerlin
 import { IUnicodeService } from 'common/services/Services';
 import { FourKeyMap } from 'common/MultiKeyMap';
 import { IdleTaskQueue } from 'common/TaskQueue';
-import { ICharAtlasConfig } from 'browser/renderer/shared/Types';
+import { ICharAtlasConfig, ITextureAtlas } from 'browser/renderer/shared/Types';
 
 // For debugging purposes, it can be useful to set this to a really tiny value,
 // to verify that LRU eviction works.
@@ -51,7 +51,7 @@ interface ICharAtlasActiveRow {
 // Work variables to avoid garbage collection
 let $glyph = undefined;
 
-export class WebglCharAtlas implements IDisposable {
+export class WebglCharAtlas implements ITextureAtlas {
   private _didWarmUp: boolean = false;
 
   private _cacheMap: FourKeyMap<number, number, number, number, IRasterizedGlyph> = new FourKeyMap();

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

@@ -9,9 +9,8 @@ import { Terminal } from 'xterm';
 import { IColorSet } from 'browser/Types';
 import { TEXT_BASELINE } from 'browser/renderer/shared/Constants';
 import { ICoreBrowserService } from 'browser/services/Services';
-import { IRenderDimensions } from 'browser/renderer/shared/Types';
+import { IRenderDimensions, ITextureAtlas } from 'browser/renderer/shared/Types';
 import { CellData } from 'common/buffer/CellData';
-import { WebglCharAtlas } from 'atlas/WebglCharAtlas';
 import { throwIfFalsy } from '../WebglUtils';
 
 export abstract class BaseRenderLayer implements IRenderLayer {
@@ -24,7 +23,7 @@ export abstract class BaseRenderLayer implements IRenderLayer {
   private _scaledCharLeft: number = 0;
   private _scaledCharTop: number = 0;
 
-  protected _charAtlas: WebglCharAtlas | undefined;
+  protected _charAtlas: ITextureAtlas | undefined;
 
   constructor(
     private _container: HTMLElement,

src/browser/renderer/shared/Types.d.ts

@@ -74,3 +74,61 @@ export interface IRenderer extends IDisposable {
   renderRows(start: number, end: number): void;
   clearTextureAtlas?(): void;
 }
+
+export interface ITextureAtlas extends IDisposable {
+  readonly cacheCanvas: HTMLCanvasElement;
+  // TODO: Add endFrame and make this readonly
+  hasCanvasChanged: boolean;
+
+  /**
+   * Warm up the texture atlas, adding common glyphs to avoid slowing early frame.
+   */
+  warmUp(): void;
+
+  /**
+   * Call when a frame is being drawn, this will return true if the atlas was cleared to make room
+   * for a new set of glyphs.
+   */
+  beginFrame(): boolean;
+
+  /**
+   * Clear all glyphs from the texture atlas.
+   */
+  clearTexture(): void;
+  getRasterizedGlyph(code: number, bg: number, fg: number, ext: number): IRasterizedGlyph;
+  getRasterizedGlyphCombinedChar(chars: string, bg: number, fg: number, ext: number): IRasterizedGlyph;
+}
+
+/**
+ * Represents a rasterized glyph within a texture atlas. Some numbers are
+ * tracked in CSS pixels as well in order to reduce calculations during the
+ * render loop.
+ */
+export interface IRasterizedGlyph {
+  /**
+   * The x and y offset between the glyph's top/left and the top/left of a cell
+   * in pixels.
+   */
+  offset: IVector;
+  /**
+   * the x and y position of the glyph in the texture in pixels.
+   */
+  texturePosition: IVector;
+  /**
+   * the x and y position of the glyph in the texture in clip space coordinates.
+   */
+  texturePositionClipSpace: IVector;
+  /**
+   * The width and height of the glyph in the texture in pixels.
+   */
+  size: IVector;
+  /**
+   * The width and height of the glyph in the texture in clip space coordinates.
+   */
+  sizeClipSpace: IVector;
+}
+
+export interface IVector {
+  x: number;
+  y: number;
+}