Implement cc::CompositorFrameMetadata StructTraits

cc/ipc/compositor_frame_metadata_struct_traits.h

+// Copyright 2016 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 CC_IPC_COMPOSITOR_FRAME_METADATA_STRUCT_TRAITS_H_
+#define CC_IPC_COMPOSITOR_FRAME_METADATA_STRUCT_TRAITS_H_
+
+#include "cc/ipc/compositor_frame_metadata.mojom.h"
+#include "cc/output/compositor_frame_metadata.h"
+
+namespace mojo {
+
+template <>
+struct StructTraits<cc::mojom::CompositorFrameMetadata,
+                    cc::CompositorFrameMetadata> {
+  static float device_scale_factor(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.device_scale_factor;
+  }
+
+  static gfx::Vector2dF root_scroll_offset(

[yzshen1, 2016/06/06 16:22:04]

Does it make sense to return a ref instead?

[Fady Samuel, 2016/06/06 20:00:11]

I'll stick to return by value because Vector2dF is only two floats.

+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.root_scroll_offset;
+  }
+
+  static float page_scale_factor(const cc::CompositorFrameMetadata& metadata) {
+    return metadata.page_scale_factor;
+  }
+
+  static gfx::SizeF scrollable_viewport_size(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.scrollable_viewport_size;
+  }
+
+  static gfx::SizeF root_layer_size(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.root_layer_size;
+  }
+
+  static float min_page_scale_factor(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.min_page_scale_factor;
+  }
+
+  static float max_page_scale_factor(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.max_page_scale_factor;
+  }
+
+  static bool root_overflow_x_hidden(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.root_overflow_x_hidden;
+  }
+
+  static bool root_overflow_y_hidden(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.root_overflow_y_hidden;
+  }
+
+  static gfx::Vector2dF location_bar_offset(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.location_bar_offset;
+  }
+
+  static gfx::Vector2dF location_bar_content_translation(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.location_bar_content_translation;
+  }
+
+  static uint32_t root_background_color(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.root_background_color;
+  }
+
+  static const cc::Selection<gfx::SelectionBound>& selection(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.selection;
+  }
+
+  static const std::vector<ui::LatencyInfo>& latency_info(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.latency_info;
+  }
+
+  static const std::vector<uint32_t>& satisfies_sequences(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.satisfies_sequences;
+  }
+
+  static const std::vector<cc::SurfaceId>& referenced_surfaces(
+      const cc::CompositorFrameMetadata& metadata) {
+    return metadata.referenced_surfaces;
+  }
+
+  static bool Read(cc::mojom::CompositorFrameMetadataDataView data,
+                   cc::CompositorFrameMetadata* out) {
+    out->device_scale_factor = data.device_scale_factor();
+    if (!data.ReadRootScrollOffset(&out->root_scroll_offset))
+      return false;
+
+    out->page_scale_factor = data.page_scale_factor();
+    if (!data.ReadScrollableViewportSize(&out->scrollable_viewport_size) ||
+        !data.ReadRootLayerSize(&out->root_layer_size)) {
+      return false;
+    }
+
+    out->min_page_scale_factor = data.min_page_scale_factor();
+    out->max_page_scale_factor = data.max_page_scale_factor();
+    out->root_overflow_x_hidden = data.root_overflow_x_hidden();
+    out->root_overflow_y_hidden = data.root_overflow_y_hidden();
+    if (!data.ReadLocationBarOffset(&out->location_bar_offset) ||
+        !data.ReadLocationBarContentTranslation(
+            &out->location_bar_content_translation)) {
+      return false;
+    }
+
+    out->root_background_color = data.root_background_color();
+    if (!data.ReadSelection(&out->selection) ||
+        !data.ReadLatencyInfo(&out->latency_info) ||
+        !data.ReadSatisfiesSequences(&out->satisfies_sequences) ||
+        !data.ReadReferencedSurfaces(&out->referenced_surfaces)) {
+      return false;
+    }
+    return true;
+  }
+};
+
+}  // namespace mojo
+
+#endif  // CC_IPC_COMPOSITOR_FRAME_METADATA_STRUCT_TRAITS_H_