aura: Add a window-targeter for windows with hit-test masks.

Use the masked-window targeter for the touch-selection handlers. Subsequent
patches will install similar targeters for the other windows that use hit-test
masks, which will allow getting rid of some hit-test mask related API from aura
and views.

BUG=318879
R=ben@chromium.org

Review URL: https://codereview.chromium.org/122573005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243287 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 81 insertions, 0 deletions

diff --git a/ui/wm/core/masked_window_targeter.cc b/ui/wm/core/masked_window_targeter.cc
new file mode 100644
index 0000000..3de6140
--- /dev/null
+++ b/ui/wm/core/masked_window_targeter.cc
@@ -0,0 +1,41 @@
+// Copyright 2014 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/wm/public/masked_window_targeter.h"
+
+#include "ui/aura/window.h"
+#include "ui/gfx/path.h"
+
+namespace wm {
+
+MaskedWindowTargeter::MaskedWindowTargeter(aura::Window* masked_window)
+    : masked_window_(masked_window) {
+}
+
+MaskedWindowTargeter::~MaskedWindowTargeter() {}
+
+bool MaskedWindowTargeter::EventLocationInsideBounds(
+    aura::Window* window,
+    const ui::LocatedEvent& event) const {
+  if (window == masked_window_) {
+    gfx::Path mask;
+    GetHitTestMask(window, &mask);
+
+    gfx::Size size = window->bounds().size();
+    SkRegion clip_region;
+    clip_region.setRect(0, 0, size.width(), size.height());
+
+    gfx::Point point = event.location();
+    if (window->parent())
+      aura::Window::ConvertPointToTarget(window->parent(), window, &point);
+
+    SkRegion mask_region;
+    return mask_region.setPath(mask, clip_region) &&
+           mask_region.contains(point.x(), point.y());
+  }
+
+  return WindowTargeter::EventLocationInsideBounds(window, event);
+}
+
+}  // namespace wm
diff --git a/ui/wm/public/masked_window_targeter.h b/ui/wm/public/masked_window_targeter.h
new file mode 100644
index 0000000..c5b4d88
--- /dev/null
+++ b/ui/wm/public/masked_window_targeter.h
@@ -0,0 +1,38 @@
+// Copyright 2014 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.
+
+#ifndef UI_WM_PUBLIC_MASKED_WINDOW_TARGETER_H_
+#define UI_WM_PUBLIC_MASKED_WINDOW_TARGETER_H_
+
+#include "ui/aura/window_targeter.h"
+
+namespace gfx {
+class Path;
+}
+
+namespace wm {
+
+class MaskedWindowTargeter : public aura::WindowTargeter {
+ public:
+  explicit MaskedWindowTargeter(aura::Window* masked_window);
+  virtual ~MaskedWindowTargeter();
+
+ protected:
+  // Sets the hit-test mask for |window| in |mask| (in |window|'s local
+  // coordinate system).
+  virtual void GetHitTestMask(aura::Window* window, gfx::Path* mask) const = 0;
+
+  // aura::WindowTargeter:
+  virtual bool EventLocationInsideBounds(
+      aura::Window* window,
+      const ui::LocatedEvent& event) const OVERRIDE;
+
+  aura::Window* masked_window_;
+
+  DISALLOW_COPY_AND_ASSIGN(MaskedWindowTargeter);
+};
+
+}  // namespace wm
+
+#endif  // UI_WM_PUBLIC_MASKED_WINDOW_TARGETER_H_
diff --git a/ui/wm/wm.gyp b/ui/wm/wm.gyp
index 725d9ea..6071fac 100644
--- a/ui/wm/wm.gyp
+++ b/ui/wm/wm.gyp
@@ -17,7 +17,9 @@
       ],
       'sources': [
         'core/easy_resize_window_targeter.cc',
+        'core/masked_window_targeter.cc',
         'public/easy_resize_window_targeter.h',
+        'public/masked_window_targeter.h',
         'public/window_types.h',
       ],
     },