Create a well-defined region that closely matches the shape of the tab to use for hit testing in the Linux tabstrip.

Review URL: http://codereview.chromium.org/62013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@13112 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 35 insertions, 36 deletions

diff --git a/chrome/browser/gtk/tabs/tab_gtk.cc b/chrome/browser/gtk/tabs/tab_gtk.cc
index bd555f4..3cd6869 100644
--- a/chrome/browser/gtk/tabs/tab_gtk.cc
+++ b/chrome/browser/gtk/tabs/tab_gtk.cc
@@ -26,6 +26,13 @@ TabGtk::TabGtk(TabDelegate* delegate)
 TabGtk::~TabGtk() {
 }
 
+bool TabGtk::IsPointInBounds(const gfx::Point& point) {
+  GdkRegion* region = MakeRegionForTab();
+  bool in_bounds = (gdk_region_point_in(region, point.x(), point.y()) == TRUE);
+  gdk_region_destroy(region);
+  return in_bounds;
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // TabGtk, TabRendererGtk overrides:
 
@@ -36,28 +43,25 @@ bool TabGtk::IsSelected() const {
 ///////////////////////////////////////////////////////////////////////////////
 // TabGtk, private:
 
-void TabGtk::MakePathForTab(gfx::Path* path) const {
-  DCHECK(path);
-
-  SkScalar h = SkIntToScalar(height());
-  SkScalar w = SkIntToScalar(width());
-
-  path->moveTo(0, h);
-
-  // Left end cap.
-  path->lineTo(kTabBottomCurveWidth, h - kTabBottomCurveWidth);
-  path->lineTo(kTabCapWidth - kTabTopCurveWidth, kTabTopCurveWidth);
-  path->lineTo(kTabCapWidth, 0);
-
-  // Connect to the right cap.
-  path->lineTo(w - kTabCapWidth, 0);
-
-  // Right end cap.
-  path->lineTo(w - kTabCapWidth - kTabTopCurveWidth, kTabTopCurveWidth);
-  path->lineTo(w - kTabBottomCurveWidth, h - kTabBottomCurveWidth);
-  path->lineTo(w, h);
-
-  // Close out the path.
-  path->lineTo(0, h);
-  path->close();
+GdkRegion* TabGtk::MakeRegionForTab()const {
+  int w = width();
+  int h = height();
+  static const int kNumRegionPoints = 9;
+
+  GdkPoint polygon[kNumRegionPoints] = {
+    { 0, h },
+    { kTabBottomCurveWidth, h - kTabBottomCurveWidth },
+    { kTabCapWidth - kTabTopCurveWidth, kTabTopCurveWidth },
+    { kTabCapWidth, 0 },
+    { w - kTabCapWidth, 0 },
+    { w - kTabCapWidth - kTabTopCurveWidth, kTabTopCurveWidth },
+    { w - kTabBottomCurveWidth, h - kTabBottomCurveWidth },
+    { w, h },
+    { 0, h },
+  };
+
+  GdkRegion* region = gdk_region_polygon(polygon, kNumRegionPoints,
+                                         GDK_WINDING_RULE);
+  gdk_region_offset(region, x(), y());
+  return region;
 }
diff --git a/chrome/browser/gtk/tabs/tab_gtk.h b/chrome/browser/gtk/tabs/tab_gtk.h
index 6dda29c..c63e046 100644
--- a/chrome/browser/gtk/tabs/tab_gtk.h
+++ b/chrome/browser/gtk/tabs/tab_gtk.h
@@ -68,13 +68,16 @@ class TabGtk : public TabRendererGtk {
   void set_closing(bool closing) { closing_ = closing; }
   bool closing() const { return closing_; }
 
-  // TabRenderer overrides:
+  // Checks whether |point| is inside the bounds of the tab.
+  bool IsPointInBounds(const gfx::Point& point);
+
+  // TabRendererGtk overrides:
   virtual bool IsSelected() const;
 
  private:
-  // Creates a path that contains the clickable region of the tab's visual
-  // representation. Used by GetViewForPoint for hit-testing.
-  void MakePathForTab(gfx::Path* path) const;
+  // Creates a clickable region of the tab's visual representation. Used for
+  // hit-testing.  Caller is responsible for destroying the region.
+  GdkRegion* MakeRegionForTab() const;
 
   // An instance of a delegate object that can perform various actions based on
   // user gestures.
diff --git a/chrome/browser/gtk/tabs/tab_renderer_gtk.cc b/chrome/browser/gtk/tabs/tab_renderer_gtk.cc
index 14e20ae..958dadd 100644
--- a/chrome/browser/gtk/tabs/tab_renderer_gtk.cc
+++ b/chrome/browser/gtk/tabs/tab_renderer_gtk.cc
@@ -186,11 +186,6 @@ void TabRendererGtk::SetBounds(const gfx::Rect& bounds) {
   Layout();
 }
 
-bool TabRendererGtk::IsPointInBounds(const gfx::Point& coord) {
-  // TODO(jhawkins): Use a GdkRegion that better maps to the shape of the tab.
-  return bounds_.Contains(coord);
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // TabRendererGtk, protected:
 
diff --git a/chrome/browser/gtk/tabs/tab_renderer_gtk.h b/chrome/browser/gtk/tabs/tab_renderer_gtk.h
index 27dd00b..ce03cad 100644
--- a/chrome/browser/gtk/tabs/tab_renderer_gtk.h
+++ b/chrome/browser/gtk/tabs/tab_renderer_gtk.h
@@ -59,9 +59,6 @@ class TabRendererGtk {
   // Paints the tab into |canvas|.
   void Paint(ChromeCanvasPaint* canvas);
 
-  // Checks whether |coord| is inside the bounds of the tab.
-  bool IsPointInBounds(const gfx::Point& coord);
-
   // Sets the hovering status of the tab.
   void SetHovering(bool hovering) { hovering_ = hovering; }