display_list/display_list.cc - mirrors/engine - Git at Google

 // Copyright 2013 The Flutter Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include <type_traits>

 #include "flutter/display_list/display_list.h"
 #include "flutter/display_list/dl_op_records.h"
 #include "flutter/fml/trace_event.h"

 namespace flutter {

 const SaveLayerOptions SaveLayerOptions::kNoAttributes = SaveLayerOptions();
 const SaveLayerOptions SaveLayerOptions::kWithAttributes =
     kNoAttributes.with_renders_with_attributes();

 DisplayList::DisplayList()
     : byte_count_(0),
       op_count_(0),
       nested_byte_count_(0),
       nested_op_count_(0),
       total_depth_(0),
       unique_id_(0),
       bounds_({0, 0, 0, 0}),
       can_apply_group_opacity_(true),
       is_ui_thread_safe_(true),
       modifies_transparent_black_(false) {}

 DisplayList::DisplayList(DisplayListStorage&& storage,
                          size_t byte_count,
                          uint32_t op_count,
                          size_t nested_byte_count,
                          uint32_t nested_op_count,
                          uint32_t total_depth,
                          const SkRect& bounds,
                          bool can_apply_group_opacity,
                          bool is_ui_thread_safe,
                          bool modifies_transparent_black,
                          sk_sp<const DlRTree> rtree)
     : storage_(std::move(storage)),
       byte_count_(byte_count),
       op_count_(op_count),
       nested_byte_count_(nested_byte_count),
       nested_op_count_(nested_op_count),
       total_depth_(total_depth),
       unique_id_(next_unique_id()),
       bounds_(bounds),
       can_apply_group_opacity_(can_apply_group_opacity),
       is_ui_thread_safe_(is_ui_thread_safe),
       modifies_transparent_black_(modifies_transparent_black),
       rtree_(std::move(rtree)) {}

 DisplayList::~DisplayList() {
   uint8_t* ptr = storage_.get();
   DisposeOps(ptr, ptr + byte_count_);
 }

 uint32_t DisplayList::next_unique_id() {
   static std::atomic<uint32_t> next_id{1};
   uint32_t id;
   do {
     id = next_id.fetch_add(+1, std::memory_order_relaxed);
   } while (id == 0);
   return id;
 }

 class Culler {
  public:
   virtual ~Culler() = default;
   virtual bool init(DispatchContext& context) = 0;
   virtual void update(DispatchContext& context) = 0;
 };
 class NopCuller final : public Culler {
  public:
   static NopCuller instance;

   ~NopCuller() = default;

   bool init(DispatchContext& context) override {
     // Setting next_render_index to 0 means that
     // all rendering ops will be at or after that
     // index so they will execute and all restore
     // indices will be after it as well so all
     // clip and transform operations will execute.
     context.next_render_index = 0;
     return true;
   }
   void update(DispatchContext& context) override {}
 };
 NopCuller NopCuller::instance = NopCuller();
 class VectorCuller final : public Culler {
  public:
   VectorCuller(const DlRTree* rtree, const std::vector<int>& rect_indices)
       : rtree_(rtree), cur_(rect_indices.begin()), end_(rect_indices.end()) {}

   ~VectorCuller() = default;

   bool init(DispatchContext& context) override {
     if (cur_ < end_) {
       context.next_render_index = rtree_->id(*cur_++);
       return true;
     } else {
       // Setting next_render_index to MAX_INT means that
       // all rendering ops will be "before" that index and
       // they will skip themselves and all clip and transform
       // ops will see that the next render index is not
       // before the next restore index (even if both are MAX_INT)
       // and so they will also not execute.
       // None of this really matters because returning false
       // here should cause the Dispatch operation to abort,
       // but this value is conceptually correct if that short
       // circuit optimization isn't used.
       context.next_render_index = std::numeric_limits<int>::max();
       return false;
     }
   }
   void update(DispatchContext& context) override {
     if (++context.cur_index > context.next_render_index) {
       while (cur_ < end_) {
         context.next_render_index = rtree_->id(*cur_++);
         if (context.next_render_index >= context.cur_index) {
           // It should be rare that we have duplicate indices
           // but if we do, then having a while loop is a cheap
           // insurance for those cases.
           // The main cause of duplicate indices is when a
           // DrawDisplayListOp was added to this DisplayList and
           // both are computing an R-Tree, in which case the
           // builder method will forward all of the child
           // DisplayList's rects to this R-Tree with the same
           // op_index.
           return;
         }
       }
       context.next_render_index = std::numeric_limits<int>::max();
     }
   }

  private:
   const DlRTree* rtree_;
   std::vector<int>::const_iterator cur_;
   std::vector<int>::const_iterator end_;
 };

 void DisplayList::Dispatch(DlOpReceiver& receiver) const {
   uint8_t* ptr = storage_.get();
   Dispatch(receiver, ptr, ptr + byte_count_, NopCuller::instance);
 }

 void DisplayList::Dispatch(DlOpReceiver& receiver,
                            const SkIRect& cull_rect) const {
   Dispatch(receiver, SkRect::Make(cull_rect));
 }

 void DisplayList::Dispatch(DlOpReceiver& receiver,
                            const SkRect& cull_rect) const {
   if (cull_rect.isEmpty()) {
     return;
   }
   if (!has_rtree() || cull_rect.contains(bounds())) {
     Dispatch(receiver);
     return;
   }
   const DlRTree* rtree = this->rtree().get();
   FML_DCHECK(rtree != nullptr);
   uint8_t* ptr = storage_.get();
   std::vector<int> rect_indices;
   rtree->search(cull_rect, &rect_indices);
   VectorCuller culler(rtree, rect_indices);
   Dispatch(receiver, ptr, ptr + byte_count_, culler);
 }

 void DisplayList::Dispatch(DlOpReceiver& receiver,
                            uint8_t* ptr,
                            uint8_t* end,
                            Culler& culler) const {
   DispatchContext context = {
       .receiver = receiver,
       .cur_index = 0,
       // next_render_index will be initialized by culler.init()
       .next_restore_index = std::numeric_limits<int>::max(),
   };
   if (!culler.init(context)) {
     return;
   }
   while (ptr < end) {
     auto op = reinterpret_cast<const DLOp*>(ptr);
     ptr += op->size;
     FML_DCHECK(ptr <= end);
     switch (op->type) {
 #define DL_OP_DISPATCH(name)                             \
   case DisplayListOpType::k##name:                       \
     static_cast<const name##Op*>(op)->dispatch(context); \
     break;

       FOR_EACH_DISPLAY_LIST_OP(DL_OP_DISPATCH)
 #ifdef IMPELLER_ENABLE_3D
       DL_OP_DISPATCH(SetSceneColorSource)
 #endif  // IMPELLER_ENABLE_3D

 #undef DL_OP_DISPATCH

       default:
         FML_DCHECK(false);
         return;
     }
     culler.update(context);
   }
 }

 void DisplayList::DisposeOps(uint8_t* ptr, uint8_t* end) {
   while (ptr < end) {
     auto op = reinterpret_cast<const DLOp*>(ptr);
     ptr += op->size;
     FML_DCHECK(ptr <= end);
     switch (op->type) {
 #define DL_OP_DISPOSE(name)                            \
   case DisplayListOpType::k##name:                     \
     if (!std::is_trivially_destructible_v<name##Op>) { \
       static_cast<const name##Op*>(op)->~name##Op();   \
     }                                                  \
     break;

       FOR_EACH_DISPLAY_LIST_OP(DL_OP_DISPOSE)
 #ifdef IMPELLER_ENABLE_3D
       DL_OP_DISPOSE(SetSceneColorSource)
 #endif  // IMPELLER_ENABLE_3D

 #undef DL_OP_DISPOSE

       default:
         FML_DCHECK(false);
         return;
     }
   }
 }

 static bool CompareOps(uint8_t* ptrA,
                        uint8_t* endA,
                        uint8_t* ptrB,
                        uint8_t* endB) {
   // These conditions are checked by the caller...
   FML_DCHECK((endA - ptrA) == (endB - ptrB));
   FML_DCHECK(ptrA != ptrB);
   uint8_t* bulk_start_a = ptrA;
   uint8_t* bulk_start_b = ptrB;
   while (ptrA < endA && ptrB < endB) {
     auto opA = reinterpret_cast<const DLOp*>(ptrA);
     auto opB = reinterpret_cast<const DLOp*>(ptrB);
     if (opA->type != opB->type || opA->size != opB->size) {
       return false;
     }
     ptrA += opA->size;
     ptrB += opB->size;
     FML_DCHECK(ptrA <= endA);
     FML_DCHECK(ptrB <= endB);
     DisplayListCompare result;
     switch (opA->type) {
 #define DL_OP_EQUALS(name)                              \
   case DisplayListOpType::k##name:                      \
     result = static_cast<const name##Op*>(opA)->equals( \
         static_cast<const name##Op*>(opB));             \
     break;

       FOR_EACH_DISPLAY_LIST_OP(DL_OP_EQUALS)
 #ifdef IMPELLER_ENABLE_3D
       DL_OP_EQUALS(SetSceneColorSource)
 #endif  // IMPELLER_ENABLE_3D

 #undef DL_OP_EQUALS

       default:
         FML_DCHECK(false);
         return false;
     }
     switch (result) {
       case DisplayListCompare::kNotEqual:
         return false;
       case DisplayListCompare::kUseBulkCompare:
         break;
       case DisplayListCompare::kEqual:
         // Check if we have a backlog of bytes to bulk compare and then
         // reset the bulk compare pointers to the address following this op
         auto bulk_bytes = reinterpret_cast<const uint8_t*>(opA) - bulk_start_a;
         if (bulk_bytes > 0) {
           if (memcmp(bulk_start_a, bulk_start_b, bulk_bytes) != 0) {
             return false;
           }
         }
         bulk_start_a = ptrA;
         bulk_start_b = ptrB;
         break;
     }
   }
   if (ptrA != endA || ptrB != endB) {
     return false;
   }
   if (bulk_start_a < ptrA) {
     // Perform a final bulk compare if we have remaining bytes waiting
     if (memcmp(bulk_start_a, bulk_start_b, ptrA - bulk_start_a) != 0) {
       return false;
     }
   }
   return true;
 }

 bool DisplayList::Equals(const DisplayList* other) const {
   if (this == other) {
     return true;
   }
   if (byte_count_ != other->byte_count_ || op_count_ != other->op_count_) {
     return false;
   }
   uint8_t* ptr = storage_.get();
   uint8_t* o_ptr = other->storage_.get();
   if (ptr == o_ptr) {
     return true;
   }
   return CompareOps(ptr, ptr + byte_count_, o_ptr, o_ptr + other->byte_count_);
 }

 }  // namespace flutter
	// Copyright 2013 The Flutter Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include <type_traits>

	#include "flutter/display_list/display_list.h"
	#include "flutter/display_list/dl_op_records.h"
	#include "flutter/fml/trace_event.h"

	namespace flutter {

	const SaveLayerOptions SaveLayerOptions::kNoAttributes = SaveLayerOptions();
	const SaveLayerOptions SaveLayerOptions::kWithAttributes =
	kNoAttributes.with_renders_with_attributes();

	DisplayList::DisplayList()
	: byte_count_(0),
	op_count_(0),
	nested_byte_count_(0),
	nested_op_count_(0),
	total_depth_(0),
	unique_id_(0),
	bounds_({0, 0, 0, 0}),
	can_apply_group_opacity_(true),
	is_ui_thread_safe_(true),
	modifies_transparent_black_(false) {}

	DisplayList::DisplayList(DisplayListStorage&& storage,
	size_t byte_count,
	uint32_t op_count,
	size_t nested_byte_count,
	uint32_t nested_op_count,
	uint32_t total_depth,
	const SkRect& bounds,
	bool can_apply_group_opacity,
	bool is_ui_thread_safe,
	bool modifies_transparent_black,
	sk_sp<const DlRTree> rtree)
	: storage_(std::move(storage)),
	byte_count_(byte_count),
	op_count_(op_count),
	nested_byte_count_(nested_byte_count),
	nested_op_count_(nested_op_count),
	total_depth_(total_depth),
	unique_id_(next_unique_id()),
	bounds_(bounds),
	can_apply_group_opacity_(can_apply_group_opacity),
	is_ui_thread_safe_(is_ui_thread_safe),
	modifies_transparent_black_(modifies_transparent_black),
	rtree_(std::move(rtree)) {}

	DisplayList::~DisplayList() {
	uint8_t* ptr = storage_.get();
	DisposeOps(ptr, ptr + byte_count_);
	}

	uint32_t DisplayList::next_unique_id() {
	static std::atomic<uint32_t> next_id{1};
	uint32_t id;
	do {
	id = next_id.fetch_add(+1, std::memory_order_relaxed);
	} while (id == 0);
	return id;
	}

	class Culler {
	public:
	virtual ~Culler() = default;
	virtual bool init(DispatchContext& context) = 0;
	virtual void update(DispatchContext& context) = 0;
	};
	class NopCuller final : public Culler {
	public:
	static NopCuller instance;

	~NopCuller() = default;

	bool init(DispatchContext& context) override {
	// Setting next_render_index to 0 means that
	// all rendering ops will be at or after that
	// index so they will execute and all restore
	// indices will be after it as well so all
	// clip and transform operations will execute.
	context.next_render_index = 0;
	return true;
	}
	void update(DispatchContext& context) override {}
	};
	NopCuller NopCuller::instance = NopCuller();
	class VectorCuller final : public Culler {
	public:
	VectorCuller(const DlRTree* rtree, const std::vector<int>& rect_indices)
	: rtree_(rtree), cur_(rect_indices.begin()), end_(rect_indices.end()) {}

	~VectorCuller() = default;

	bool init(DispatchContext& context) override {
	if (cur_ < end_) {
	context.next_render_index = rtree_->id(*cur_++);
	return true;
	} else {
	// Setting next_render_index to MAX_INT means that
	// all rendering ops will be "before" that index and
	// they will skip themselves and all clip and transform
	// ops will see that the next render index is not
	// before the next restore index (even if both are MAX_INT)
	// and so they will also not execute.
	// None of this really matters because returning false
	// here should cause the Dispatch operation to abort,
	// but this value is conceptually correct if that short
	// circuit optimization isn't used.
	context.next_render_index = std::numeric_limits<int>::max();
	return false;
	}
	}
	void update(DispatchContext& context) override {
	if (++context.cur_index > context.next_render_index) {
	while (cur_ < end_) {
	context.next_render_index = rtree_->id(*cur_++);
	if (context.next_render_index >= context.cur_index) {
	// It should be rare that we have duplicate indices
	// but if we do, then having a while loop is a cheap
	// insurance for those cases.
	// The main cause of duplicate indices is when a
	// DrawDisplayListOp was added to this DisplayList and
	// both are computing an R-Tree, in which case the
	// builder method will forward all of the child
	// DisplayList's rects to this R-Tree with the same
	// op_index.
	return;
	}
	}
	context.next_render_index = std::numeric_limits<int>::max();
	}
	}

	private:
	const DlRTree* rtree_;
	std::vector<int>::const_iterator cur_;
	std::vector<int>::const_iterator end_;
	};

	void DisplayList::Dispatch(DlOpReceiver& receiver) const {
	uint8_t* ptr = storage_.get();
	Dispatch(receiver, ptr, ptr + byte_count_, NopCuller::instance);
	}

	void DisplayList::Dispatch(DlOpReceiver& receiver,
	const SkIRect& cull_rect) const {
	Dispatch(receiver, SkRect::Make(cull_rect));
	}

	void DisplayList::Dispatch(DlOpReceiver& receiver,
	const SkRect& cull_rect) const {
	if (cull_rect.isEmpty()) {
	return;
	}
	if (!has_rtree() \|\| cull_rect.contains(bounds())) {
	Dispatch(receiver);
	return;
	}
	const DlRTree* rtree = this->rtree().get();
	FML_DCHECK(rtree != nullptr);
	uint8_t* ptr = storage_.get();
	std::vector<int> rect_indices;
	rtree->search(cull_rect, &rect_indices);
	VectorCuller culler(rtree, rect_indices);
	Dispatch(receiver, ptr, ptr + byte_count_, culler);
	}

	void DisplayList::Dispatch(DlOpReceiver& receiver,
	uint8_t* ptr,
	uint8_t* end,
	Culler& culler) const {
	DispatchContext context = {
	.receiver = receiver,
	.cur_index = 0,
	// next_render_index will be initialized by culler.init()
	.next_restore_index = std::numeric_limits<int>::max(),
	};
	if (!culler.init(context)) {
	return;
	}
	while (ptr < end) {
	auto op = reinterpret_cast<const DLOp*>(ptr);
	ptr += op->size;
	FML_DCHECK(ptr <= end);
	switch (op->type) {
	#define DL_OP_DISPATCH(name) \
	case DisplayListOpType::k##name: \
	static_cast<const name##Op*>(op)->dispatch(context); \
	break;

	FOR_EACH_DISPLAY_LIST_OP(DL_OP_DISPATCH)
	#ifdef IMPELLER_ENABLE_3D
	DL_OP_DISPATCH(SetSceneColorSource)
	#endif // IMPELLER_ENABLE_3D

	#undef DL_OP_DISPATCH

	default:
	FML_DCHECK(false);
	return;
	}
	culler.update(context);
	}
	}

	void DisplayList::DisposeOps(uint8_t* ptr, uint8_t* end) {
	while (ptr < end) {
	auto op = reinterpret_cast<const DLOp*>(ptr);
	ptr += op->size;
	FML_DCHECK(ptr <= end);
	switch (op->type) {
	#define DL_OP_DISPOSE(name) \
	case DisplayListOpType::k##name: \
	if (!std::is_trivially_destructible_v<name##Op>) { \
	static_cast<const name##Op*>(op)->~name##Op(); \
	} \
	break;

	FOR_EACH_DISPLAY_LIST_OP(DL_OP_DISPOSE)
	#ifdef IMPELLER_ENABLE_3D
	DL_OP_DISPOSE(SetSceneColorSource)
	#endif // IMPELLER_ENABLE_3D

	#undef DL_OP_DISPOSE

	default:
	FML_DCHECK(false);
	return;
	}
	}
	}

	static bool CompareOps(uint8_t* ptrA,
	uint8_t* endA,
	uint8_t* ptrB,
	uint8_t* endB) {
	// These conditions are checked by the caller...
	FML_DCHECK((endA - ptrA) == (endB - ptrB));
	FML_DCHECK(ptrA != ptrB);
	uint8_t* bulk_start_a = ptrA;
	uint8_t* bulk_start_b = ptrB;
	while (ptrA < endA && ptrB < endB) {
	auto opA = reinterpret_cast<const DLOp*>(ptrA);
	auto opB = reinterpret_cast<const DLOp*>(ptrB);
	if (opA->type != opB->type \|\| opA->size != opB->size) {
	return false;
	}
	ptrA += opA->size;
	ptrB += opB->size;
	FML_DCHECK(ptrA <= endA);
	FML_DCHECK(ptrB <= endB);
	DisplayListCompare result;
	switch (opA->type) {
	#define DL_OP_EQUALS(name) \
	case DisplayListOpType::k##name: \
	result = static_cast<const name##Op*>(opA)->equals( \
	static_cast<const name##Op*>(opB)); \
	break;

	FOR_EACH_DISPLAY_LIST_OP(DL_OP_EQUALS)
	#ifdef IMPELLER_ENABLE_3D
	DL_OP_EQUALS(SetSceneColorSource)
	#endif // IMPELLER_ENABLE_3D

	#undef DL_OP_EQUALS

	default:
	FML_DCHECK(false);
	return false;
	}
	switch (result) {
	case DisplayListCompare::kNotEqual:
	return false;
	case DisplayListCompare::kUseBulkCompare:
	break;
	case DisplayListCompare::kEqual:
	// Check if we have a backlog of bytes to bulk compare and then
	// reset the bulk compare pointers to the address following this op
	auto bulk_bytes = reinterpret_cast<const uint8_t*>(opA) - bulk_start_a;
	if (bulk_bytes > 0) {
	if (memcmp(bulk_start_a, bulk_start_b, bulk_bytes) != 0) {
	return false;
	}
	}
	bulk_start_a = ptrA;
	bulk_start_b = ptrB;
	break;
	}
	}
	if (ptrA != endA \|\| ptrB != endB) {
	return false;
	}
	if (bulk_start_a < ptrA) {
	// Perform a final bulk compare if we have remaining bytes waiting
	if (memcmp(bulk_start_a, bulk_start_b, ptrA - bulk_start_a) != 0) {
	return false;
	}
	}
	return true;
	}

	bool DisplayList::Equals(const DisplayList* other) const {
	if (this == other) {
	return true;
	}
	if (byte_count_ != other->byte_count_ \|\| op_count_ != other->op_count_) {
	return false;
	}
	uint8_t* ptr = storage_.get();
	uint8_t* o_ptr = other->storage_.get();
	if (ptr == o_ptr) {
	return true;
	}
	return CompareOps(ptr, ptr + byte_count_, o_ptr, o_ptr + other->byte_count_);
	}

	} // namespace flutter