Support for Adaptive Handle Orientation

content/browser/android/composited_touch_handle_drawable.cc

Index: content/browser/android/composited_touch_handle_drawable.cc
diff --git a/content/browser/android/composited_touch_handle_drawable.cc b/content/browser/android/composited_touch_handle_drawable.cc
index 91a019eba89157780bd68ed5d82c979b050d0c88..55feffdbf4c295ea5261c84c145c500d13d9c68d 100644
--- a/content/browser/android/composited_touch_handle_drawable.cc
+++ b/content/browser/android/composited_touch_handle_drawable.cc
@@ -101,30 +101,61 @@ void CompositedTouchHandleDrawable::SetEnabled(bool enabled) {
     UpdateLayerPosition();
 }
 
-void CompositedTouchHandleDrawable::SetOrientation(
-    ui::TouchHandleOrientation orientation) {
+void CompositedTouchHandleDrawable::SetLayout(
+    const gfx::PointF& position,
+    ui::TouchHandleOrientation orientation,
+    bool mirror_vertical,
+    bool mirror_horizontal,
+    bool mirror_changed) {
   DCHECK(layer_->parent());
+  bool orientation_changed = orientation_ != orientation;
+  focal_position_ = gfx::ScalePoint(position, dpi_scale_);
+
   orientation_ = orientation;
 
   const SkBitmap& bitmap = g_selection_resources.Get().GetBitmap(orientation);

[jdduke (slow), 2015/06/03 18:59:00]

Can we move the bitmap/bitmap_height/bitmap_width into the (orientation_changed)
branch?

Then below we can just do:

gfx::Size bounds = layer_->bounds();

and use that where we otherwise used the bitmap. A minor detail, but it avoids
fetching the bitmap every update.

[AviD, 2015/06/08 08:51:37]

Done.

-  layer_->SetBitmap(bitmap);
-  layer_->SetBounds(gfx::Size(bitmap.width(), bitmap.height()));
+  const int bitmap_height = bitmap.height();
+  const int bitmap_width = bitmap.width();
+
+  if (orientation_changed) {
+    layer_->SetBitmap(bitmap);
+    layer_->SetBounds(gfx::Size(bitmap_width, bitmap_height));
+  }
+
+  // Invert about X and Y axis based on the mirror values
+  if (mirror_changed) {
+    gfx::Transform transform;
+    float scale_x = mirror_horizontal ? -1.f : 1.f;
+    float scale_y = mirror_vertical ? -1.f : 1.f;
+
+    layer_->SetTransformOrigin(
+        gfx::Point3F(bitmap_width * 0.5f, bitmap_height * 0.5f, 0));
+    transform.Scale(scale_x, scale_y);
+    layer_->SetTransform(transform);
+  }
 
+  // Set the Focal offsets for the composited handle layer
+  // based on the orientation
+  int focal_offset_x = 0;
+  int focal_offset_y = mirror_vertical ? bitmap_height : 0;
   switch (orientation_) {
     case ui::TouchHandleOrientation::LEFT:
-      focal_offset_from_origin_ = gfx::Vector2dF(bitmap.width() * 0.75f, 0);
+      focal_offset_x =
+          mirror_horizontal ? bitmap_width * 0.25f : bitmap_width * 0.75f;
       break;
     case ui::TouchHandleOrientation::RIGHT:
-      focal_offset_from_origin_ = gfx::Vector2dF(bitmap.width() * 0.25f, 0);
+      focal_offset_x =
+          mirror_horizontal ? bitmap_width * 0.75f : bitmap_width * 0.25f;
       break;
     case ui::TouchHandleOrientation::CENTER:
-      focal_offset_from_origin_ = gfx::Vector2dF(bitmap.width() * 0.5f, 0);
+      focal_offset_x = bitmap_width * 0.5f;
       break;
     case ui::TouchHandleOrientation::UNDEFINED:
       NOTREACHED() << "Invalid touch handle orientation.";
       break;
   };
 
+  focal_offset_from_origin_ = gfx::Vector2dF(focal_offset_x, focal_offset_y);
   UpdateLayerPosition();
 }
 
@@ -136,12 +167,6 @@ void CompositedTouchHandleDrawable::SetAlpha(float alpha) {
   layer_->SetHideLayerAndSubtree(hidden);
 }
 
-void CompositedTouchHandleDrawable::SetFocus(const gfx::PointF& position) {
-  DCHECK(layer_->parent());
-  focal_position_ = gfx::ScalePoint(position, dpi_scale_);
-  UpdateLayerPosition();
-}
-
 gfx::RectF CompositedTouchHandleDrawable::GetVisibleBounds() const {
   return gfx::ScaleRect(gfx::RectF(layer_->position().x(),
                                    layer_->position().y(),