Add API to clear canvas renderer texture atlas

src/browser/Terminal.ts

@@ -1292,6 +1292,10 @@ export class Terminal extends CoreTerminal implements ITerminal {
     this.viewport?.syncScrollArea();
   }
 
+  public clearTextureAtlas(): void {
+    this._renderService?.clearTextureAtlas();
+  }
+
   private _reportWindowsOptions(type: WindowsOptionsReportType): void {
     if (!this._renderService) {
       return;

src/browser/TestUtils.test.ts

@@ -195,6 +195,9 @@ export class MockTerminal implements ITerminal {
   public reset(): void {
     throw new Error('Method not implemented.');
   }
+  public clearTextureAtlas(): void {
+    throw new Error('Method not implemented.');
+  }
   public refresh(start: number, end: number): void {
     throw new Error('Method not implemented.');
   }
@@ -374,6 +377,9 @@ export class MockRenderService implements IRenderService {
   public refreshRows(start: number, end: number): void {
     throw new Error('Method not implemented.');
   }
+  public clearTextureAtlas(): void {
+    throw new Error('Method not implemented.');
+  }
   public resize(cols: number, rows: number): void {
     throw new Error('Method not implemented.');
   }

src/browser/Types.d.ts

@@ -79,6 +79,7 @@ export interface IPublicTerminal extends IDisposable {
   write(data: string | Uint8Array, callback?: () => void): void;
   paste(data: string): void;
   refresh(start: number, end: number): void;
+  clearTextureAtlas(): void;
   reset(): void;
 }
 

src/browser/public/Terminal.ts

@@ -222,6 +222,9 @@ export class Terminal implements ITerminalApi {
   public reset(): void {
     this._core.reset();
   }
+  public clearTextureAtlas(): void {
+    this._core.clearTextureAtlas();
+  }
   public loadAddon(addon: ITerminalAddon): void {
     return this._addonManager.loadAddon(this, addon);
   }

src/browser/renderer/BaseRenderLayer.ts

@@ -138,6 +138,10 @@ export abstract class BaseRenderLayer implements IRenderLayer {
 
   public abstract reset(): void;
 
+  public clearTextureAtlas(): void {
+    this._charAtlas?.clear();
+  }
+
   /**
    * Fills 1+ cells completely. This uses the existing fillStyle on the context.
    * @param x The column to start at.

src/browser/renderer/Renderer.ts

@@ -149,6 +149,12 @@ export class Renderer extends Disposable implements IRenderer {
     }
   }
 
+  public clearTextureAtlas(): void {
+    for (const layer of this._renderLayers) {
+      layer.clearTextureAtlas();
+    }
+  }
+
   /**
    * Recalculates the character and canvas dimensions.
    */

src/browser/renderer/Types.d.ts

@@ -52,6 +52,7 @@ export interface IRenderer extends IDisposable {
   onOptionsChanged(): void;
   clear(): void;
   renderRows(start: number, end: number): void;
+  clearTextureAtlas?(): void;
 }
 
 export interface IRenderLayer extends IDisposable {
@@ -100,4 +101,9 @@ export interface IRenderLayer extends IDisposable {
    * Clear the state of the render layer.
    */
   reset(): void;
+
+  /**
+   * Clears the texture atlas.
+   */
+  clearTextureAtlas(): void;
 }

src/browser/renderer/atlas/BaseCharAtlas.ts

@@ -28,6 +28,8 @@ export abstract class BaseCharAtlas implements IDisposable {
    */
   private _doWarmUp(): void { }
 
+  public clear(): void { }
+
   /**
    * Called when we start drawing a new frame.
    *

src/browser/renderer/atlas/DynamicCharAtlas.ts

@@ -119,6 +119,16 @@ export class DynamicCharAtlas extends BaseCharAtlas {
     this._drawToCacheCount = 0;
   }
 
+  public clear(): void {
+    if (this._cacheMap.size > 0) {
+      const capacity = this._width * this._height;
+      this._cacheMap = new LRUMap(capacity);
+      this._cacheMap.prealloc(capacity);
+    }
+    this._cacheCtx.clearRect(0, 0, TEXTURE_WIDTH, TEXTURE_HEIGHT);
+    this._tmpCtx.clearRect(0, 0, this._config.scaledCharWidth, this._config.scaledCharHeight);
+  }
+
   public draw(
     ctx: CanvasRenderingContext2D,
     glyph: IGlyphIdentifier,

src/browser/services/RenderService.ts

@@ -168,6 +168,11 @@ export class RenderService extends Disposable implements IRenderService {
     }
   }
 
+  public clearTextureAtlas(): void {
+    this._renderer?.clearTextureAtlas?.();
+    this._fullRefresh();
+  }
+
   public setColors(colors: IColorSet): void {
     this._renderer.setColors(colors);
     this._fullRefresh();

src/browser/services/Services.ts

@@ -53,6 +53,7 @@ export interface IRenderService extends IDisposable {
   dimensions: IRenderDimensions;
 
   refreshRows(start: number, end: number): void;
+  clearTextureAtlas(): void;
   resize(cols: number, rows: number): void;
   changeOptions(): void;
   setRenderer(renderer: IRenderer): void;

typings/xterm.d.ts

@@ -1056,6 +1056,14 @@ declare module 'xterm' {
      */
     refresh(start: number, end: number): void;
 
+    /**
+     * Clears the texture atlas of the canvas renderer if it's active. Doing this will force a
+     * redraw of all glyphs which can workaround issues causing the texture to become corrupt, for
+     * example Chromium/Nvidia has an issue where the texture gets messed up when resuming the OS
+     * from sleep.
+     */
+    clearTextureAtlas(): void;
+
     /**
      * Perform a full reset (RIS, aka '\x1bc').
      */