components/viz/common/quads/compositor_frame_metadata.h - chromium/src - Git at Google

 // Copyright (c) 2012 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 COMPONENTS_VIZ_COMMON_QUADS_COMPOSITOR_FRAME_METADATA_H_
 #define COMPONENTS_VIZ_COMMON_QUADS_COMPOSITOR_FRAME_METADATA_H_

 #include <stdint.h>

 #include <vector>
 #include "base/optional.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
 #include "components/viz/common/frame_sinks/begin_frame_args.h"
 #include "components/viz/common/quads/frame_deadline.h"
 #include "components/viz/common/surfaces/surface_id.h"
 #include "components/viz/common/surfaces/surface_range.h"
 #include "components/viz/common/viz_common_export.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/gfx/geometry/size_f.h"
 #include "ui/gfx/geometry/vector2d_f.h"
 #include "ui/latency/latency_info.h"

 #if defined(OS_ANDROID)
 #include "components/viz/common/quads/selection.h"
 #include "ui/gfx/selection_bound.h"
 #endif  // defined(OS_ANDROID)

 namespace viz {

 // Compares two frame tokens, handling cases where the token wraps around the
 // 32-bit max value.
 inline bool FrameTokenGT(uint32_t token1, uint32_t token2) {
   // There will be underflow in the subtraction if token1 was created
   // after token2.
   return (token2 - token1) > 0x80000000u;
 }

 class VIZ_COMMON_EXPORT FrameTokenGenerator {
  public:
   inline uint32_t operator++() {
     if (++frame_token_ == 0)
       ++frame_token_;
     return frame_token_;
   }

   inline uint32_t operator*() const { return frame_token_; }

  private:
   uint32_t frame_token_ = 0;
 };

 class VIZ_COMMON_EXPORT CompositorFrameMetadata {
  public:
   CompositorFrameMetadata();
   CompositorFrameMetadata(CompositorFrameMetadata&& other);
   ~CompositorFrameMetadata();

   CompositorFrameMetadata& operator=(CompositorFrameMetadata&& other);

   CompositorFrameMetadata Clone() const;

   // The device scale factor used to generate this compositor frame.
   float device_scale_factor = 0.f;

   // Scroll offset and scale of the root layer. This can be used for tasks
   // like positioning windowed plugins.
   gfx::Vector2dF root_scroll_offset;
   float page_scale_factor = 0.f;

   gfx::SizeF scrollable_viewport_size;

   bool may_contain_video = false;

   // WebView makes quality decisions for rastering resourceless software frames
   // based on information that a scroll or animation is active.
   // TODO(aelias): Remove this and always enable filtering if there aren't apps
   // depending on this anymore.
   bool is_resourceless_software_draw_with_scroll_or_animation = false;

   // This color is usually obtained from the background color of the <body>
   // element. It can be used for filling in gutter areas around the frame when
   // it's too small to fill the box the parent reserved for it.
   SkColor root_background_color = SK_ColorWHITE;

   std::vector<ui::LatencyInfo> latency_info;

   // This is the set of Surfaces that are referenced by this frame.
   // Note: this includes occluded and clipped surfaces and surfaces that may
   // be accessed by this CompositorFrame in the future.
   // TODO(fsamuel): In the future, a generalized frame eviction system will
   // determine which surfaces to retain and which to evict. It will likely
   // be unnecessary for the embedder to explicitly specify which surfaces to
   // retain. Thus, this field will likely go away.
   std::vector<SurfaceRange> referenced_surfaces;

   // This is the set of dependent SurfaceIds that should be active in the
   // display compositor before this CompositorFrame can be activated. Note
   // that if |can_activate_before_dependencies| then the display compositor
   // can choose to activate a CompositorFrame before all dependencies are
   // available.
   // Note: |activation_dependencies| and |referenced_surfaces| are disjoint
   //       sets of surface IDs. If a surface ID is known to exist and can be
   //       used without additional synchronization, then it is placed in
   //       |referenced_surfaces|. |activation_dependencies| is the set of
   //       surface IDs that this frame would like to block on until they
   //       become available or a deadline hits.
   std::vector<SurfaceId> activation_dependencies;

   // This specifies a deadline for this CompositorFrame to synchronize with its
   // activation dependencies. Once this deadline passes, this CompositorFrame
   // should be forcibly activated. This deadline may be lower-bounded by the
   // default synchronization deadline specified by the system.
   FrameDeadline deadline;

   // This is a value that allows the browser to associate compositor frames
   // with the content that they represent -- typically top-level page loads.
   // TODO(kenrb, fsamuel): This should eventually by SurfaceID, when they
   // become available in all renderer processes. See https://crbug.com/695579.
   uint32_t content_source_id = 0;

   // BeginFrameAck for the BeginFrame that this CompositorFrame answers.
   BeginFrameAck begin_frame_ack;

   // An identifier for the frame. This is used to identify the frame for
   // presentation-feedback, or when the frame-token is sent to the embedder.
   // For comparing |frame_token| from different frames, use |FrameTokenGT()|
   // instead of directly comparing them, since the tokens wrap around back to 1
   // after the 32-bit max value.
   // TODO(crbug.com/850386): A custom type would be better to avoid incorrect
   // comparisons.
   uint32_t frame_token = 0;

   // Once the display compositor processes a frame with
   // |send_frame_token_to_embedder| flag turned on, the |frame_token| for the
   // frame is sent to embedder of the frame. This is helpful when the embedder
   // wants to do something after a particular frame is processed.
   bool send_frame_token_to_embedder = false;

   // Once the display compositor presents a frame with
   // |request_presentation_feedback| flag turned on, a presentation feedback
   // will be provided to CompositorFrameSinkClient.
   bool request_presentation_feedback = true;

   // These limits can be used together with the scroll/scale fields above to
   // determine if scrolling/scaling in a particular direction is possible.
   float min_page_scale_factor = 0.f;

   // Used to position the location top bar and page content, whose precise
   // position is computed by the renderer compositor.
   float top_controls_height = 0.f;
   float top_controls_shown_ratio = 0.f;

   // The time at which the LocalSurfaceId used to submit this CompositorFrame
   // was allocated.
   base::TimeTicks local_surface_id_allocation_time;

 #if defined(OS_ANDROID)
   float max_page_scale_factor = 0.f;
   gfx::SizeF root_layer_size;
   bool root_overflow_y_hidden = false;

   // Used to position Android bottom bar, whose position is computed by the
   // renderer compositor.
   float bottom_controls_height = 0.f;
   float bottom_controls_shown_ratio = 0.f;

   // Provides selection region updates relative to the current viewport. If the
   // selection is empty or otherwise unused, the bound types will indicate such.
   Selection<gfx::SelectionBound> selection;
 #endif  // defined(OS_ANDROID)

  private:
   CompositorFrameMetadata(const CompositorFrameMetadata& other);
   CompositorFrameMetadata operator=(const CompositorFrameMetadata&) = delete;
 };

 }  // namespace viz

 #endif  // COMPONENTS_VIZ_COMMON_QUADS_COMPOSITOR_FRAME_METADATA_H_
	// Copyright (c) 2012 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 COMPONENTS_VIZ_COMMON_QUADS_COMPOSITOR_FRAME_METADATA_H_
	#define COMPONENTS_VIZ_COMMON_QUADS_COMPOSITOR_FRAME_METADATA_H_

	#include <stdint.h>

	#include <vector>
	#include "base/optional.h"
	#include "base/time/time.h"
	#include "build/build_config.h"
	#include "components/viz/common/frame_sinks/begin_frame_args.h"
	#include "components/viz/common/quads/frame_deadline.h"
	#include "components/viz/common/surfaces/surface_id.h"
	#include "components/viz/common/surfaces/surface_range.h"
	#include "components/viz/common/viz_common_export.h"
	#include "third_party/skia/include/core/SkColor.h"
	#include "ui/gfx/geometry/size_f.h"
	#include "ui/gfx/geometry/vector2d_f.h"
	#include "ui/latency/latency_info.h"

	#if defined(OS_ANDROID)
	#include "components/viz/common/quads/selection.h"
	#include "ui/gfx/selection_bound.h"
	#endif // defined(OS_ANDROID)

	namespace viz {

	// Compares two frame tokens, handling cases where the token wraps around the
	// 32-bit max value.
	inline bool FrameTokenGT(uint32_t token1, uint32_t token2) {
	// There will be underflow in the subtraction if token1 was created
	// after token2.
	return (token2 - token1) > 0x80000000u;
	}

	class VIZ_COMMON_EXPORT FrameTokenGenerator {
	public:
	inline uint32_t operator++() {
	if (++frame_token_ == 0)
	++frame_token_;
	return frame_token_;
	}

	inline uint32_t operator*() const { return frame_token_; }

	private:
	uint32_t frame_token_ = 0;
	};

	class VIZ_COMMON_EXPORT CompositorFrameMetadata {
	public:
	CompositorFrameMetadata();
	CompositorFrameMetadata(CompositorFrameMetadata&& other);
	~CompositorFrameMetadata();

	CompositorFrameMetadata& operator=(CompositorFrameMetadata&& other);

	CompositorFrameMetadata Clone() const;

	// The device scale factor used to generate this compositor frame.
	float device_scale_factor = 0.f;

	// Scroll offset and scale of the root layer. This can be used for tasks
	// like positioning windowed plugins.
	gfx::Vector2dF root_scroll_offset;
	float page_scale_factor = 0.f;

	gfx::SizeF scrollable_viewport_size;

	bool may_contain_video = false;

	// WebView makes quality decisions for rastering resourceless software frames
	// based on information that a scroll or animation is active.
	// TODO(aelias): Remove this and always enable filtering if there aren't apps
	// depending on this anymore.
	bool is_resourceless_software_draw_with_scroll_or_animation = false;

	// This color is usually obtained from the background color of the <body>
	// element. It can be used for filling in gutter areas around the frame when
	// it's too small to fill the box the parent reserved for it.
	SkColor root_background_color = SK_ColorWHITE;

	std::vector<ui::LatencyInfo> latency_info;

	// This is the set of Surfaces that are referenced by this frame.
	// Note: this includes occluded and clipped surfaces and surfaces that may
	// be accessed by this CompositorFrame in the future.
	// TODO(fsamuel): In the future, a generalized frame eviction system will
	// determine which surfaces to retain and which to evict. It will likely
	// be unnecessary for the embedder to explicitly specify which surfaces to
	// retain. Thus, this field will likely go away.
	std::vector<SurfaceRange> referenced_surfaces;

	// This is the set of dependent SurfaceIds that should be active in the
	// display compositor before this CompositorFrame can be activated. Note
	// that if \|can_activate_before_dependencies\| then the display compositor
	// can choose to activate a CompositorFrame before all dependencies are
	// available.
	// Note: \|activation_dependencies\| and \|referenced_surfaces\| are disjoint
	// sets of surface IDs. If a surface ID is known to exist and can be
	// used without additional synchronization, then it is placed in
	// \|referenced_surfaces\|. \|activation_dependencies\| is the set of
	// surface IDs that this frame would like to block on until they
	// become available or a deadline hits.
	std::vector<SurfaceId> activation_dependencies;

	// This specifies a deadline for this CompositorFrame to synchronize with its
	// activation dependencies. Once this deadline passes, this CompositorFrame
	// should be forcibly activated. This deadline may be lower-bounded by the
	// default synchronization deadline specified by the system.
	FrameDeadline deadline;

	// This is a value that allows the browser to associate compositor frames
	// with the content that they represent -- typically top-level page loads.
	// TODO(kenrb, fsamuel): This should eventually by SurfaceID, when they
	// become available in all renderer processes. See https://crbug.com/695579.
	uint32_t content_source_id = 0;

	// BeginFrameAck for the BeginFrame that this CompositorFrame answers.
	BeginFrameAck begin_frame_ack;

	// An identifier for the frame. This is used to identify the frame for
	// presentation-feedback, or when the frame-token is sent to the embedder.
	// For comparing \|frame_token\| from different frames, use \|FrameTokenGT()\|
	// instead of directly comparing them, since the tokens wrap around back to 1
	// after the 32-bit max value.
	// TODO(crbug.com/850386): A custom type would be better to avoid incorrect
	// comparisons.
	uint32_t frame_token = 0;

	// Once the display compositor processes a frame with
	// \|send_frame_token_to_embedder\| flag turned on, the \|frame_token\| for the
	// frame is sent to embedder of the frame. This is helpful when the embedder
	// wants to do something after a particular frame is processed.
	bool send_frame_token_to_embedder = false;

	// Once the display compositor presents a frame with
	// \|request_presentation_feedback\| flag turned on, a presentation feedback
	// will be provided to CompositorFrameSinkClient.
	bool request_presentation_feedback = true;

	// These limits can be used together with the scroll/scale fields above to
	// determine if scrolling/scaling in a particular direction is possible.
	float min_page_scale_factor = 0.f;

	// Used to position the location top bar and page content, whose precise
	// position is computed by the renderer compositor.
	float top_controls_height = 0.f;
	float top_controls_shown_ratio = 0.f;

	// The time at which the LocalSurfaceId used to submit this CompositorFrame
	// was allocated.
	base::TimeTicks local_surface_id_allocation_time;

	#if defined(OS_ANDROID)
	float max_page_scale_factor = 0.f;
	gfx::SizeF root_layer_size;
	bool root_overflow_y_hidden = false;

	// Used to position Android bottom bar, whose position is computed by the
	// renderer compositor.
	float bottom_controls_height = 0.f;
	float bottom_controls_shown_ratio = 0.f;

	// Provides selection region updates relative to the current viewport. If the
	// selection is empty or otherwise unused, the bound types will indicate such.
	Selection<gfx::SelectionBound> selection;
	#endif // defined(OS_ANDROID)

	private:
	CompositorFrameMetadata(const CompositorFrameMetadata& other);
	CompositorFrameMetadata operator=(const CompositorFrameMetadata&) = delete;
	};

	} // namespace viz

	#endif // COMPONENTS_VIZ_COMMON_QUADS_COMPOSITOR_FRAME_METADATA_H_