1 files changed, 165 insertions, 0 deletions
diff --git a/devtools/server/primitive.js b/devtools/server/primitive.js
new file mode 100644
index 000000000..45346bc78
--- /dev/null
+++ b/devtools/server/primitive.js
@@ -0,0 +1,165 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+"use strict";
+
+const { on, once, off, emit } = require("sdk/event/core");
+const { Class } = require("sdk/core/heritage");
+
+const WebGLPrimitivesType = {
+  "POINTS": 0,
+  "LINES": 1,
+  "LINE_LOOP": 2,
+  "LINE_STRIP": 3,
+  "TRIANGLES": 4,
+  "TRIANGLE_STRIP": 5,
+  "TRIANGLE_FAN": 6
+};
+
+/**
+ * A utility for monitoring WebGL primitive draws. Takes a `tabActor`
+ * and monitors primitive draws over time.
+ */
+const WebGLDrawArrays = "drawArrays";
+const WebGLDrawElements = "drawElements";
+
+var WebGLPrimitiveCounter = exports.WebGLPrimitiveCounter = Class({
+  initialize: function (tabActor) {
+    this.tabActor = tabActor;
+  },
+
+  destroy: function () {
+    this.stopRecording();
+  },
+
+  /**
+   * Starts monitoring primitive draws, storing the primitives count per tick.
+   */
+  resetCounts: function () {
+    this._tris = 0;
+    this._vertices = 0;
+    this._points = 0;
+    this._lines = 0;
+    this._startTime = this.tabActor.docShell.now();
+  },
+
+  /**
+   * Stops monitoring primitive draws, returning the recorded values.
+   */
+  getCounts: function () {
+    var result = {
+      tris: this._tris,
+      vertices: this._vertices,
+      points: this._points,
+      lines: this._lines
+    };
+
+    this._tris = 0;
+    this._vertices = 0;
+    this._points = 0;
+    this._lines = 0;
+    return result;
+  },
+
+  /**
+   * Handles WebGL draw primitive functions to catch primitive info.
+   */
+  handleDrawPrimitive: function (functionCall) {
+    let { name, args } = functionCall.details;
+
+    if (name === WebGLDrawArrays) {
+      this._processDrawArrays(args);
+    } else if (name === WebGLDrawElements) {
+      this._processDrawElements(args);
+    }
+  },
+
+  /**
+   * Processes WebGL drawArrays method to count primitve numbers
+   */
+  _processDrawArrays: function (args) {
+    let mode = args[0];
+    let count = args[2];
+
+    switch (mode) {
+      case WebGLPrimitivesType.POINTS:
+        this._vertices += count;
+        this._points += count;
+        break;
+      case WebGLPrimitivesType.LINES:
+        this._vertices += count;
+        this._lines += (count / 2);
+        break;
+      case WebGLPrimitivesType.LINE_LOOP:
+        this._vertices += count;
+        this._lines += count;
+        break;
+      case WebGLPrimitivesType.LINE_STRIP:
+        this._vertices += count;
+        this._lines += (count - 1);
+        break;
+      case WebGLPrimitivesType.TRIANGLES:
+        this._tris += (count / 3);
+        this._vertices += count;
+        break;
+      case WebGLPrimitivesType.TRIANGLE_STRIP:
+        this._tris += (count - 2);
+        this._vertices += count;
+        break;
+      case WebGLPrimitivesType.TRIANGLE_FAN:
+        this._tris += (count - 2);
+        this._vertices += count;
+        break;
+      default:
+        console.error("_processDrawArrays doesn't define this type.");
+        break;
+    }
+  },
+
+  /**
+   * Processes WebGL drawElements method to count primitve numbers
+   */
+  _processDrawElements: function (args) {
+    let mode = args[0];
+    let count = args[1];
+
+    switch (mode) {
+      case WebGLPrimitivesType.POINTS:
+        this._vertices += count;
+        this._points += count;
+        break;
+      case WebGLPrimitivesType.LINES:
+        this._vertices += count;
+        this._lines += (count / 2);
+        break;
+      case WebGLPrimitivesType.LINE_LOOP:
+        this._vertices += count;
+        this._lines += count;
+        break;
+      case WebGLPrimitivesType.LINE_STRIP:
+        this._vertices += count;
+        this._lines += (count - 1);
+        break;
+      case WebGLPrimitivesType.TRIANGLES:
+        let tris = count / 3;
+        let vertex = tris * 3;
+
+        if (tris > 1) {
+          vertex = tris * 2;
+        }
+        this._tris += tris;
+        this._vertices += vertex;
+        break;
+      case WebGLPrimitivesType.TRIANGLE_STRIP:
+        this._tris += (count - 2);
+        this._vertices += count;
+        break;
+      case WebGLPrimitivesType.TRIANGLE_FAN:
+        this._tris += (count - 2);
+        this._vertices += count;
+      default:
+        console.error("_processDrawElements doesn't define this type.");
+        break;
+    }
+  }
+});