From 31669cbad654e7e9f1ae3c1c98b4f758b762873c Mon Sep 17 00:00:00 2001
From: Daniel Imms <daimms@microsoft.com>
Date: Wed, 11 Dec 2019 14:21:09 -0800
Subject: [PATCH] Expose texture atlas as API and use in demo

Part of #2623
---
 addons/xterm-addon-webgl/src/WebglAddon.ts              | 9 ++++++++-
 addons/xterm-addon-webgl/src/WebglRenderer.ts           | 4 ++++
 addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts    | 3 ---
 addons/xterm-addon-webgl/typings/xterm-addon-webgl.d.ts | 2 ++
 demo/client.ts                                          | 8 ++++++++
 5 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/addons/xterm-addon-webgl/src/WebglAddon.ts b/addons/xterm-addon-webgl/src/WebglAddon.ts
index be867d754e..3cf45f3522 100644
--- a/addons/xterm-addon-webgl/src/WebglAddon.ts
+++ b/addons/xterm-addon-webgl/src/WebglAddon.ts
@@ -10,6 +10,7 @@ import { IColorSet } from 'browser/Types';
 
 export class WebglAddon implements ITerminalAddon {
   private _terminal?: Terminal;
+  private _renderer?: WebglRenderer;
 
   constructor(
     private _preserveDrawingBuffer?: boolean
@@ -22,7 +23,8 @@ export class WebglAddon implements ITerminalAddon {
     this._terminal = terminal;
     const renderService: IRenderService =  (<any>terminal)._core._renderService;
     const colors: IColorSet = (<any>terminal)._core._colorManager.colors;
-    renderService.setRenderer(new WebglRenderer(terminal, colors, this._preserveDrawingBuffer));
+    this._renderer = new WebglRenderer(terminal, colors, this._preserveDrawingBuffer);
+    renderService.setRenderer(this._renderer);
   }
 
   public dispose(): void {
@@ -32,5 +34,10 @@ export class WebglAddon implements ITerminalAddon {
     const renderService: IRenderService = (<any>this._terminal)._core._renderService;
     renderService.setRenderer((<any>this._terminal)._core._createRenderer());
     renderService.onResize(this._terminal.cols, this._terminal.rows);
+    this._renderer = undefined;
+  }
+
+  public get textureAtlas(): HTMLCanvasElement | undefined {
+    return this._renderer?.textureAtlas;
   }
 }
diff --git a/addons/xterm-addon-webgl/src/WebglRenderer.ts b/addons/xterm-addon-webgl/src/WebglRenderer.ts
index 6f98d2c196..ae85d9a012 100644
--- a/addons/xterm-addon-webgl/src/WebglRenderer.ts
+++ b/addons/xterm-addon-webgl/src/WebglRenderer.ts
@@ -100,6 +100,10 @@ export class WebglRenderer extends Disposable implements IRenderer {
     super.dispose();
   }
 
+  public get textureAtlas(): HTMLCanvasElement | undefined {
+    return this._charAtlas?.cacheCanvas;
+  }
+
   public setColors(colors: IColorSet): void {
     this._colors = colors;
     // Clear layers and force a full render
diff --git a/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts b/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts
index c96c2a6957..5c3fb23916 100644
--- a/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts
+++ b/addons/xterm-addon-webgl/src/atlas/WebglCharAtlas.ts
@@ -86,9 +86,6 @@ export class WebglCharAtlas implements IDisposable {
     this._tmpCanvas.width = this._config.scaledCharWidth * 2 + TMP_CANVAS_GLYPH_PADDING * 2;
     this._tmpCanvas.height = this._config.scaledCharHeight + TMP_CANVAS_GLYPH_PADDING * 2;
     this._tmpCtx = throwIfFalsy(this._tmpCanvas.getContext('2d', {alpha: this._config.allowTransparency}));
-
-    // This is useful for debugging
-    document.body.appendChild(this.cacheCanvas);
   }
 
   public dispose(): void {
diff --git a/addons/xterm-addon-webgl/typings/xterm-addon-webgl.d.ts b/addons/xterm-addon-webgl/typings/xterm-addon-webgl.d.ts
index 5199a2609c..9586433a98 100644
--- a/addons/xterm-addon-webgl/typings/xterm-addon-webgl.d.ts
+++ b/addons/xterm-addon-webgl/typings/xterm-addon-webgl.d.ts
@@ -10,6 +10,8 @@ declare module 'xterm-addon-webgl' {
    * An xterm.js addon that provides search functionality.
    */
   export class WebglAddon implements ITerminalAddon {
+    public textureAtlas?: HTMLCanvasElement;
+
     constructor(preserveDrawingBuffer?: boolean);
 
     /**
diff --git a/demo/client.ts b/demo/client.ts
index 5b76700ead..6d146264b0 100644
--- a/demo/client.ts
+++ b/demo/client.ts
@@ -343,7 +343,15 @@ function initAddons(term: TerminalType): void {
       if (checkbox.checked) {
         addon.instance = new addon.ctor();
         term.loadAddon(addon.instance);
+        if (name === 'webgl') {
+          setTimeout(() => {
+            document.body.appendChild((addon.instance as WebglAddon).textureAtlas);
+          }, 0);
+        }
       } else {
+        if (name === 'webgl') {
+          document.body.removeChild((addon.instance as WebglAddon).textureAtlas);
+        }
         addon.instance!.dispose();
         addon.instance = undefined;
       }