Palette tool laser prototype.

ash/common/system/chromeos/palette/tools/laser_pointer_points.cc

Index: ash/common/system/chromeos/palette/tools/laser_pointer_points.cc
diff --git a/ash/common/system/chromeos/palette/tools/laser_pointer_points.cc b/ash/common/system/chromeos/palette/tools/laser_pointer_points.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7256b42af012919692341970abc128a89ddd1fee
--- /dev/null
+++ b/ash/common/system/chromeos/palette/tools/laser_pointer_points.cc
@@ -0,0 +1,74 @@
+// Copyright 2016 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.
+
+#include "ash/common/system/chromeos/palette/tools/laser_pointer_points.h"
+
+#include <algorithm>
+#include <limits>
+
+namespace ash {
+
+LaserPointerPoints::LaserPointerPoints(base::TimeDelta life_duration)
+    : life_duration_(life_duration) {}
+
+LaserPointerPoints::~LaserPointerPoints() {}
+
+void LaserPointerPoints::AddPoint(const gfx::Point& point) {
+  LaserPoint new_point;
+  new_point.location = point;
+  new_point.creation_time = base::Time::Now();
+  points_.push_back(new_point);
+  ClearOldPoints();
+}
+
+void LaserPointerPoints::Clear() {
+  points_.clear();
+}
+
+gfx::Rect LaserPointerPoints::GetBoundingBox() {
+  if (IsEmpty())
+    return gfx::Rect();
+
+  gfx::Point min_point = GetOldest().location;
+  gfx::Point max_point = GetOldest().location;
+  for (const LaserPoint& point : points_) {
+    min_point.SetToMin(point.location);
+    max_point.SetToMax(point.location);
+  }
+  return gfx::BoundingRect(min_point, max_point);
+}
+
+LaserPointerPoints::LaserPoint LaserPointerPoints::GetOldest() const {
+  DCHECK(!IsEmpty());
+  return points_.front();
+}
+
+LaserPointerPoints::LaserPoint LaserPointerPoints::GetNewest() const {
+  DCHECK(!IsEmpty());
+  return points_.back();
+}
+
+bool LaserPointerPoints::IsEmpty() const {
+  return points_.empty();
+}
+
+int LaserPointerPoints::GetNumberOfPoints() const {
+  return points_.size();
+}
+
+const std::deque<LaserPointerPoints::LaserPoint>&
+LaserPointerPoints::laser_points() {
+  return points_;
+}
+
+void LaserPointerPoints::ClearOldPoints() {
+  DCHECK(!IsEmpty());
+  auto first_alive_point =
+      std::find_if(points_.begin(), points_.end(), [this](LaserPoint& p) {
+        return GetNewest().creation_time - p.creation_time < life_duration_;
+      });
+  points_.erase(points_.begin(), first_alive_point);
+}
+
+}  // namespace ash