WIP Hittest Component.

components/viz/hit_test/public/interfaces/hit_test_data.mojom

+// Copyright 2017 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.
+
+module viz.hit_test.mojom;
+
+import "cc/ipc/surface_id.mojom";
+import "ui/gfx/geometry/mojo/geometry.mojom";
+import "ui/gfx/mojo/transform.mojom";
+
+enum HitTestRegionFlags { 
+
+  // Region maps to this surface ( me ).  

[rjkroege, 2017/06/09 15:47:08]

The bounds flag is still necessary. Please put it back. See board:

// The rect in this region is the tightest enclosing rect for all of the
provided regions.
HTR_BOUND

These need to be powers of 2 so you can | them together.

+  HIT_TEST_MINE = 0,
+
+  // Region ignored for hit testing ( transparent backgrounds & hover:none ).
+  HIT_TEST_IGNORE,
+
+  // Region maps to child surface ( OOPIF ).  
+  HIT_TEST_CHILD_SURFACE,  
+  
+  // Irregular boundary - send HitTestRequest to resolve. 
+  HIT_TEST_ASK,          
+
+  // No touch event handler exists - no need to send touch events.
+  HIT_TEST_NO_TOUCH_EVENT_HANDLER, 
+
+};
+
+struct HitTestRegion {
+
+    // Flags to indicate the type of HitTestRegion.
+    HitTestRegionFlags flags_;
+
+    // SurfaceId is required when flags_ = HIT_TEST_CHILD_SURFACE.
+    cc.mojom.SurfaceId surface_id_;
+
+    // The rect of the region in the coordinate space of the embedder.
+    gfx.mojom.Rect rect_;
+
+    // The transform applied to the child region. 
+    gfx.mojom.Transform transform_;
+};
+
+struct HitTestData {
+
+  // SurfaceId corresponding to this HitTestData.
+  cc.mojom.SurfaceId surface_id_;
+
+  // The list of sub-regions in this surface.
+  array<HitTestRegion> regions_; // in front to back z-order 
+};