Initial webgl renderer implementation

src/renderer/webgl/RenderModel.ts

@@ -0,0 +1,59 @@
+/**
+ * Copyright (c) 2018 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+import { IRenderModel, ISelectionRenderModel } from './Types';
+
+export const RENDER_MODEL_INDICIES_PER_CELL = 4;
+
+// HACK: Cannot use INVERTED_DEFAULT_COLOR (-1) here because _model.cells is a
+// Uint32Array. This should be changed when true color is introduced to whatever
+// the mechanism is for the buffer.
+export const RENDER_INVERTED_DEFAULT_COLOR = 258;
+
+export const COMBINED_CHAR_BIT_MASK = 0x80000000;
+
+export class RenderModel implements IRenderModel {
+  public cells: Uint32Array;
+  public lineLengths: Uint32Array;
+  public selection: ISelectionRenderModel;
+
+  constructor() {
+    this.cells = new Uint32Array(0);
+    this.lineLengths = new Uint32Array(0);
+    this.selection = {
+      hasSelection: false,
+      viewportStartRow: 0,
+      viewportEndRow: 0,
+      viewportCappedStartRow: 0,
+      viewportCappedEndRow: 0,
+      startCol: 0,
+      endCol: 0
+    };
+  }
+
+  public resize(cols: number, rows: number): void {
+    const indexCount = cols * rows * RENDER_MODEL_INDICIES_PER_CELL;
+    if (indexCount !== this.cells.length) {
+      this.cells = new Uint32Array(indexCount);
+      this.lineLengths = new Uint32Array(rows);
+    }
+  }
+
+  public clear(): void {
+    this.cells.fill(0, 0);
+    this.lineLengths.fill(0, 0);
+    this.clearSelection();
+  }
+
+  public clearSelection(): void {
+    this.selection.hasSelection = false;
+    this.selection.viewportStartRow = 0;
+    this.selection.viewportEndRow = 0;
+    this.selection.viewportCappedStartRow = 0;
+    this.selection.viewportCappedEndRow = 0;
+    this.selection.startCol = 0;
+    this.selection.endCol = 0;
+  }
+}