1 files changed, 66 insertions, 0 deletions
diff --git a/gfx/layers/wr/HitTestInfoManager.h b/gfx/layers/wr/HitTestInfoManager.h
new file mode 100644
index 0000000000..5ee7b566dc
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+++ b/gfx/layers/wr/HitTestInfoManager.h
@@ -0,0 +1,66 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef GFX_HITTESTINFOMANAGER_H
+#define GFX_HITTESTINFOMANAGER_H
+
+#include "mozilla/gfx/CompositorHitTestInfo.h"
+#include "mozilla/layers/ScrollableLayerGuid.h"
+#include "mozilla/webrender/WebRenderAPI.h"
+#include "nsRect.h"
+
+namespace mozilla {
+
+class nsDisplayItem;
+class nsDisplayListBuilder;
+
+namespace wr {
+class DisplayListBuilder;
+}
+
+namespace layers {
+
+/**
+ * This class extracts the hit testing information (area, flags, ViewId) from
+ * Gecko display items and pushes them into WebRender display list.
+ *
+ * The hit testing information is deduplicated: a new hit test item is only
+ * added if the new area is not contained in the previous area, or if the flags,
+ * ViewId, or current spatial id is different.
+ */
+class HitTestInfoManager {
+ public:
+  HitTestInfoManager();
+
+  /**
+   * Resets the previous hit testing information.
+   */
+  void Reset();
+
+  /**
+   * Extracts the hit testing information from |aItem|, and if necessary, adds
+   * a new WebRender hit test item using |aBuilder|.
+   *
+   * Returns true if a hit test item was pushed.
+   */
+  bool ProcessItem(nsDisplayItem* aItem, wr::DisplayListBuilder& aBuilder,
+                   nsDisplayListBuilder* aDisplayListBuilder);
+
+ private:
+  bool Update(const nsRect& aArea, const gfx::CompositorHitTestInfo& aFlags,
+              const ScrollableLayerGuid::ViewID& aViewId,
+              const wr::WrSpaceAndClipChain& aSpaceAndClip);
+
+  nsRect mArea;
+  gfx::CompositorHitTestInfo mFlags;
+  ScrollableLayerGuid::ViewID mViewId;
+  wr::WrSpaceAndClipChain mSpaceAndClipChain;
+};
+
+}  // namespace layers
+}  // namespace mozilla
+
+#endif