Merge branch 'reuse_bufferlines' of git+ssh://github.com/jerch/xterm.js into reuse_bufferlines

Author: jerch

src/Buffer.ts

@@ -55,10 +55,13 @@ export class Buffer implements IBuffer {
   }
 
   public setBufferLineFactory(type: string): void {
+    this.lines.recycling = false;
+    this.lines.recycleHeap = [];
     if (type === 'TypedArray') {
       if (this._bufferLineConstructor !== BufferLineTypedArray) {
         this._bufferLineConstructor = BufferLineTypedArray;
         this._recreateLines();
+        this.lines.recycling = true;
       }
     } else {
       if (this._bufferLineConstructor !== BufferLine) {
@@ -81,8 +84,26 @@ export class Buffer implements IBuffer {
   }
 
   public getBlankLine(attr: number, isWrapped?: boolean): IBufferLine {
-    const fillCharData: CharData = [attr, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE];
-    return new this._bufferLineConstructor(this._terminal.cols, fillCharData, isWrapped);
+    // JS array without recycling
+    if (this._bufferLineConstructor === BufferLine) {
+      const fillCharData: CharData = [attr, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE];
+      return new this._bufferLineConstructor(this._terminal.cols, fillCharData, isWrapped);
+    }
+
+    // typed array with recycling
+    let blank: IBufferLine = (this as any)._blank;
+    if (!blank || blank.length !== this._terminal.cols) {
+      const fillCharData: CharData = [attr, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE];
+      blank = new this._bufferLineConstructor(this._terminal.cols, fillCharData, isWrapped);
+      (this as any)._blank = blank;
+    }
+    blank.isWrapped = !!(isWrapped);
+    const recycled = this.lines.recycleHeap.pop();
+    if (recycled) {
+      recycled.copyFrom(blank);
+      return recycled;
+    }
+    return blank.clone();
   }
 
   public get hasScrollback(): boolean {
@@ -126,7 +147,7 @@ export class Buffer implements IBuffer {
    * Clears the buffer to it's initial state, discarding all previous data.
    */
   public clear(): void {
-    this.setBufferLineFactory(this._terminal.options.experimentalBufferLineImpl);
+    // this.setBufferLineFactory(this._terminal.options.experimentalBufferLineImpl);
     this.ydisp = 0;
     this.ybase = 0;
     this.y = 0;
@@ -135,6 +156,7 @@ export class Buffer implements IBuffer {
     this.scrollTop = 0;
     this.scrollBottom = this._terminal.rows - 1;
     this.setupTabStops();
+    this.setBufferLineFactory(this._terminal.options.experimentalBufferLineImpl);
   }
 
   /**

src/common/CircularList.ts

@@ -14,6 +14,8 @@ export class CircularList<T> extends EventEmitter implements ICircularList<T> {
   protected _array: (T | undefined)[];
   private _startIndex: number;
   private _length: number;
+  public recycleHeap: T[];
+  public recycling: boolean = false;
 
   constructor(
     private _maxLength: number
@@ -22,6 +24,7 @@ export class CircularList<T> extends EventEmitter implements ICircularList<T> {
     this._array = new Array<T>(this._maxLength);
     this._startIndex = 0;
     this._length = 0;
+    this.recycleHeap = [];
   }
 
   public get maxLength(): number {
@@ -79,6 +82,13 @@ export class CircularList<T> extends EventEmitter implements ICircularList<T> {
    * @param value The value to set.
    */
   public set(index: number, value: T | undefined): void {
+    if (this.recycling) {
+      const line = this._array[this._getCyclicIndex(this._length)];
+      if (line) {
+        this.recycleHeap.push(line);
+      }
+    }
+
     this._array[this._getCyclicIndex(index)] = value;
   }
 
@@ -88,6 +98,13 @@ export class CircularList<T> extends EventEmitter implements ICircularList<T> {
    * @param value The value to push onto the list.
    */
   public push(value: T): void {
+    if (this.recycling) {
+      const line = this._array[this._getCyclicIndex(this._length)];
+      if (line) {
+        this.recycleHeap.push(line);
+      }
+    }
+
     this._array[this._getCyclicIndex(this._length)] = value;
     if (this._length === this._maxLength) {
       this._startIndex++;
@@ -139,6 +156,13 @@ export class CircularList<T> extends EventEmitter implements ICircularList<T> {
     // Delete items
     if (deleteCount) {
       for (let i = start; i < this._length - deleteCount; i++) {
+        if (this.recycling) {
+          const line = this._array[this._getCyclicIndex(this._length)];
+          if (line) {
+            this.recycleHeap.push(line);
+          }
+        }
+
         this._array[this._getCyclicIndex(i)] = this._array[this._getCyclicIndex(i + deleteCount)];
       }
       this._length -= deleteCount;

src/common/Types.ts

@@ -24,6 +24,8 @@ export interface IKeyboardEvent {
 export interface ICircularList<T> extends IEventEmitter {
   length: number;
   maxLength: number;
+  recycleHeap: T[];
+  recycling: boolean;
 
   get(index: number): T | undefined;
   set(index: number, value: T): void;