[cc] Initial checkin of cc-frame-viewer

tools/cc-frame-viewer/src/base/range.js

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+'use strict';
+
+/**
+ * @fileoverview Quick range computations.
+ */
+base.exportTo('base', function() {
+
+  function Range() {
+    this.isEmpty_ = true;
+    this.min_ = undefined;
+    this.max_ = undefined;
+  };
+
+  Range.prototype = {
+    __proto__: Object.prototype,
+
+    reset: function() {
+      this.isEmpty_ = true;
+      this.min_ = undefined;
+      this.max_ = undefined;
+    },
+
+    get isEmpty() {
+      return this.isEmpty_;
+    },
+
+    addRange: function(range) {
+      if (range.isEmpty)
+        return;
+      this.addValue(range.min);
+      this.addValue(range.max);
+    },
+
+    addValue: function(value) {
+      if (this.isEmpty_) {
+        this.max_ = value;
+        this.min_ = value;
+        this.isEmpty_ = false;
+        return;
+      }
+      this.max_ = Math.max(this.max_, value);
+      this.min_ = Math.min(this.min_, value);
+    },
+
+    get min() {
+      if (this.isEmpty_)
+        return undefined;
+      return this.min_;
+    },
+
+    get max() {
+      if (this.isEmpty_)
+        return undefined;
+      return this.max_;
+    },
+  };
+
+  return {
+    Range: Range
+  };
+
+});