Centered flood fill style ink drop ripples on mouse/touch points.

ui/views/animation/flood_fill_ink_drop_ripple.cc

 // 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 "ui/views/animation/flood_fill_ink_drop_ripple.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "third_party/skia/include/core/SkColor.h"
@@ skipping 298 matching lines @@
   gfx::Transform transform = gfx::Transform();
   transform.Translate(center_point_.x() - root_layer_.bounds().x(),
                       center_point_.y() - root_layer_.bounds().y());
   transform.Scale(target_scale, target_scale);
   transform.Translate(-drawn_center_point.x(), -drawn_center_point.y());
 
   return transform;
 }
 
 gfx::Transform FloodFillInkDropRipple::GetMaxSizeTargetTransform() const {
-  // TODO(estade): get rid of this 2, but make the fade out start before the
-  // active/action transform is done.
-  return CalculateTransform(gfx::Vector2dF(root_layer_.bounds().width(),
-                                           root_layer_.bounds().height())
-                                .Length() /
-                            2);
+  return CalculateTransform(MaxDistanceToCorners(center_point_));
+}
+
+float FloodFillInkDropRipple::MaxDistanceToCorners(
+    const gfx::Point& point) const {
+  const gfx::Rect bounds = root_layer_.bounds();
+  const float distance_to_top_left = (bounds.origin() - point).Length();
+  const float distance_to_top_right = (bounds.top_right() - point).Length();
+  const float distance_to_bottom_left = (bounds.bottom_left() - point).Length();
+  const float distance_to_bottom_right =
+      (bounds.bottom_right() - point).Length();
+
+  float largest_distance =
+      std::max(distance_to_top_left, distance_to_top_right);
+  largest_distance = std::max(largest_distance, distance_to_bottom_left);
+  largest_distance = std::max(largest_distance, distance_to_bottom_right);
+  return largest_distance;
 }
 
 }  // namespace views