libs/hwui/DeferredDisplayList.cpp - platform/frameworks/base - Gitiles

 /*
  * Copyright (C) 2013 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #define LOG_TAG "OpenGLRenderer"
 #define ATRACE_TAG ATRACE_TAG_VIEW

 #include <SkCanvas.h>

 #include <utils/Trace.h>

 #include "Caches.h"
 #include "Debug.h"
 #include "DisplayListOp.h"
 #include "OpenGLRenderer.h"

 #if DEBUG_DEFER
     #define DEFER_LOGD(...) ALOGD(__VA_ARGS__)
 #else
     #define DEFER_LOGD(...)
 #endif

 namespace android {
 namespace uirenderer {

 // Depth of the save stack at the beginning of batch playback at flush time
 #define FLUSH_SAVE_STACK_DEPTH 2

 /////////////////////////////////////////////////////////////////////////////////
 // Operation Batches
 /////////////////////////////////////////////////////////////////////////////////

 class DrawOpBatch {
 public:
     DrawOpBatch() { mOps.clear(); }

     virtual ~DrawOpBatch() { mOps.clear(); }

     void add(DrawOp* op) {
         // NOTE: ignore empty bounds special case, since we don't merge across those ops
         mBounds.unionWith(op->state.mBounds);
         mOps.add(op);
     }

     virtual bool intersects(Rect& rect) {
         if (!rect.intersects(mBounds)) return false;

         for (unsigned int i = 0; i < mOps.size(); i++) {
             if (rect.intersects(mOps[i]->state.mBounds)) {
 #if DEBUG_DEFER
                 DEFER_LOGD("op intersects with op %p with bounds %f %f %f %f:", mOps[i],
                         mOps[i]->state.mBounds.left, mOps[i]->state.mBounds.top,
                         mOps[i]->state.mBounds.right, mOps[i]->state.mBounds.bottom);
                 mOps[i]->output(2);
 #endif
                 return true;
             }
         }
         return false;
     }

     virtual status_t replay(OpenGLRenderer& renderer, Rect& dirty) {
         DEFER_LOGD("replaying draw batch %p", this);

         status_t status = DrawGlInfo::kStatusDone;
         DisplayListLogBuffer& logBuffer = DisplayListLogBuffer::getInstance();
         for (unsigned int i = 0; i < mOps.size(); i++) {
             DrawOp* op = mOps[i];

             renderer.restoreDisplayState(op->state);

 #if DEBUG_DISPLAY_LIST_OPS_AS_EVENTS
             renderer.eventMark(op->name());
 #endif
             status |= op->applyDraw(renderer, dirty, 0);
             logBuffer.writeCommand(0, op->name());
         }
         return status;
     }

     inline int count() const { return mOps.size(); }
 private:
     Vector<DrawOp*> mOps;
     Rect mBounds;
 };

 class StateOpBatch : public DrawOpBatch {
 public:
     // creates a single operation batch
     StateOpBatch(StateOp* op) : mOp(op) {}

     bool intersects(Rect& rect) {
         // if something checks for intersection, it's trying to go backwards across a state op,
         // something not currently supported - state ops are always barriers
         CRASH();
         return false;
     }

     virtual status_t replay(OpenGLRenderer& renderer, Rect& dirty) {
         DEFER_LOGD("replaying state op batch %p", this);
         renderer.restoreDisplayState(mOp->state);

         // use invalid save count because it won't be used at flush time - RestoreToCountOp is the
         // only one to use it, and we don't use that class at flush time, instead calling
         // renderer.restoreToCount directly
         int saveCount = -1;
         mOp->applyState(renderer, saveCount);
         return DrawGlInfo::kStatusDone;
     }

 private:
     const StateOp* mOp;
 };

 class RestoreToCountBatch : public DrawOpBatch {
 public:
     RestoreToCountBatch(StateOp* op, int restoreCount) : mOp(op), mRestoreCount(restoreCount) {}

     bool intersects(Rect& rect) {
         // if something checks for intersection, it's trying to go backwards across a state op,
         // something not currently supported - state ops are always barriers
         CRASH();
         return false;
     }

     virtual status_t replay(OpenGLRenderer& renderer, Rect& dirty) {
         DEFER_LOGD("batch %p restoring to count %d", this, mRestoreCount);

         renderer.restoreDisplayState(mOp->state);
         renderer.restoreToCount(mRestoreCount);
         return DrawGlInfo::kStatusDone;
     }

 private:
     // we use the state storage for the RestoreToCountOp, but don't replay the op itself
     const StateOp* mOp;
     /*
      * The count used here represents the flush() time saveCount. This is as opposed to the
      * DisplayList record time, or defer() time values (which are RestoreToCountOp's mCount, and
      * (saveCount + mCount) respectively). Since the count is different from the original
      * RestoreToCountOp, we don't store a pointer to the op, as elsewhere.
      */
     const int mRestoreCount;
 };

 /////////////////////////////////////////////////////////////////////////////////
 // DeferredDisplayList
 /////////////////////////////////////////////////////////////////////////////////

 void DeferredDisplayList::resetBatchingState() {
     for (int i = 0; i < kOpBatch_Count; i++) {
         mBatchIndices[i] = -1;
     }
 }

 void DeferredDisplayList::clear() {
     resetBatchingState();
     mComplexClipStackStart = -1;

     for (unsigned int i = 0; i < mBatches.size(); i++) {
         delete mBatches[i];
     }
     mBatches.clear();
     mSaveStack.clear();
 }

 /////////////////////////////////////////////////////////////////////////////////
 // Operation adding
 /////////////////////////////////////////////////////////////////////////////////

 int DeferredDisplayList::getStateOpDeferFlags() const {
     // For both clipOp and save(Layer)Op, we don't want to save drawing info, and only want to save
     // the clip if we aren't recording a complex clip (and can thus trust it to be a rect)
     return recordingComplexClip() ? 0 : kStateDeferFlag_Clip;
 }

 int DeferredDisplayList::getDrawOpDeferFlags() const {
     return kStateDeferFlag_Draw | getStateOpDeferFlags();
 }

 /**
  * When an clipping operation occurs that could cause a complex clip, record the operation and all
  * subsequent clipOps, save/restores (if the clip flag is set). During a flush, instead of loading
  * the clip from deferred state, we play back all of the relevant state operations that generated
  * the complex clip.
  *
  * Note that we don't need to record the associated restore operation, since operations at defer
  * time record whether they should store the renderer's current clip
  */
 void DeferredDisplayList::addClip(OpenGLRenderer& renderer, ClipOp* op) {
     if (recordingComplexClip() || op->canCauseComplexClip() || !renderer.hasRectToRectTransform()) {
         DEFER_LOGD("%p Received complex clip operation %p", this, op);

         // NOTE: defer clip op before setting mComplexClipStackStart so previous clip is recorded
         storeStateOpBarrier(renderer, op);

         if (!recordingComplexClip()) {
             mComplexClipStackStart = renderer.getSaveCount() - 1;
             DEFER_LOGD("    Starting complex clip region, start is %d", mComplexClipStackStart);
         }
     }
 }

 /**
  * For now, we record save layer operations as barriers in the batch list, preventing drawing
  * operations from reordering around the saveLayer and it's associated restore()
  *
  * In the future, we should send saveLayer commands (if they can be played out of order) and their
  * contained drawing operations to a seperate list of batches, so that they may draw at the
  * beginning of the frame. This would avoid targetting and removing an FBO in the middle of a frame.
  *
  * saveLayer operations should be pulled to the beginning of the frame if the canvas doesn't have a
  * complex clip, and if the flags (kClip_SaveFlag & kClipToLayer_SaveFlag) are set.
  */
 void DeferredDisplayList::addSaveLayer(OpenGLRenderer& renderer,
         SaveLayerOp* op, int newSaveCount) {
     DEFER_LOGD("%p adding saveLayerOp %p, flags %x, new count %d",
             this, op, op->getFlags(), newSaveCount);

     storeStateOpBarrier(renderer, op);
     mSaveStack.push(newSaveCount);
 }

 /**
  * Takes save op and it's return value - the new save count - and stores it into the stream as a
  * barrier if it's needed to properly modify a complex clip
  */
 void DeferredDisplayList::addSave(OpenGLRenderer& renderer, SaveOp* op, int newSaveCount) {
     int saveFlags = op->getFlags();
     DEFER_LOGD("%p adding saveOp %p, flags %x, new count %d", this, op, saveFlags, newSaveCount);

     if (recordingComplexClip() && (saveFlags & SkCanvas::kClip_SaveFlag)) {
         // store and replay the save operation, as it may be needed to correctly playback the clip
         DEFER_LOGD("    adding save barrier with new save count %d", newSaveCount);
         storeStateOpBarrier(renderer, op);
         mSaveStack.push(newSaveCount);
     }
 }

 /**
  * saveLayer() commands must be associated with a restoreToCount batch that will clean up and draw
  * the layer in the deferred list
  *
  * other save() commands which occur as children of a snapshot with complex clip will be deferred,
  * and must be restored
  *
  * Either will act as a barrier to draw operation reordering, as we want to play back layer
  * save/restore and complex canvas modifications (including save/restore) in order.
  */
 void DeferredDisplayList::addRestoreToCount(OpenGLRenderer& renderer, StateOp* op,
         int newSaveCount) {
     DEFER_LOGD("%p addRestoreToCount %d", this, newSaveCount);

     if (recordingComplexClip() && newSaveCount <= mComplexClipStackStart) {
         mComplexClipStackStart = -1;
         resetBatchingState();
     }

     if (mSaveStack.isEmpty() || newSaveCount > mSaveStack.top()) {
         return;
     }

     while (!mSaveStack.isEmpty() && mSaveStack.top() >= newSaveCount) mSaveStack.pop();

     storeRestoreToCountBarrier(renderer, op, mSaveStack.size() + FLUSH_SAVE_STACK_DEPTH);
 }

 void DeferredDisplayList::addDrawOp(OpenGLRenderer& renderer, DrawOp* op) {
     if (renderer.storeDisplayState(op->state, getDrawOpDeferFlags())) {
         return; // quick rejected
     }

     op->onDrawOpDeferred(renderer);

     if (CC_UNLIKELY(renderer.getCaches().drawReorderDisabled)) {
         // TODO: elegant way to reuse batches?
         DrawOpBatch* b = new DrawOpBatch();
         b->add(op);
         mBatches.add(b);
         return;
     }

     // disallowReorder isn't set, so find the latest batch of the new op's type, and try to merge
     // the new op into it
     DrawOpBatch* targetBatch = NULL;
     int batchId = op->getBatchId();

     if (!mBatches.isEmpty()) {
         if (op->state.mBounds.isEmpty()) {
             // don't know the bounds for op, so add to last batch and start from scratch on next op
             mBatches.top()->add(op);
             for (int i = 0; i < kOpBatch_Count; i++) {
                 mBatchIndices[i] = -1;
             }
 #if DEBUG_DEFER
             DEFER_LOGD("Warning: Encountered op with empty bounds, resetting batches");
             op->output(2);
 #endif
             return;
         }

         if (batchId >= 0 && mBatchIndices[batchId] != -1) {
             int targetIndex = mBatchIndices[batchId];
             targetBatch = mBatches[targetIndex];
             // iterate back toward target to see if anything drawn since should overlap the new op
             for (int i = mBatches.size() - 1; i > targetIndex; i--) {
                 DrawOpBatch* overBatch = mBatches[i];
                 if (overBatch->intersects(op->state.mBounds)) {
                     targetBatch = NULL;
 #if DEBUG_DEFER
                     DEFER_LOGD("op couldn't join batch %d, was intersected by batch %d",
                             targetIndex, i);
                     op->output(2);
 #endif
                     break;
                 }
             }
         }
     }
     if (!targetBatch) {
         targetBatch = new DrawOpBatch();
         mBatches.add(targetBatch);
         if (batchId >= 0) {
             mBatchIndices[batchId] = mBatches.size() - 1;
         }
     }
     targetBatch->add(op);
 }

 void DeferredDisplayList::storeStateOpBarrier(OpenGLRenderer& renderer, StateOp* op) {
     DEFER_LOGD("%p adding state op barrier at pos %d", this, mBatches.size());

     renderer.storeDisplayState(op->state, getStateOpDeferFlags());
     mBatches.add(new StateOpBatch(op));
     resetBatchingState();
 }

 void DeferredDisplayList::storeRestoreToCountBarrier(OpenGLRenderer& renderer, StateOp* op,
         int newSaveCount) {
     DEFER_LOGD("%p adding restore to count %d barrier, pos %d",
             this, newSaveCount, mBatches.size());

     // store displayState for the restore operation, as it may be associated with a saveLayer that
     // doesn't have kClip_SaveFlag set
     renderer.storeDisplayState(op->state, getStateOpDeferFlags());
     mBatches.add(new RestoreToCountBatch(op, newSaveCount));
     resetBatchingState();
 }

 /////////////////////////////////////////////////////////////////////////////////
 // Replay / flush
 /////////////////////////////////////////////////////////////////////////////////

 static status_t replayBatchList(Vector<DrawOpBatch*>& batchList,
         OpenGLRenderer& renderer, Rect& dirty) {
     status_t status = DrawGlInfo::kStatusDone;

     int opCount = 0;
     for (unsigned int i = 0; i < batchList.size(); i++) {
         status |= batchList[i]->replay(renderer, dirty);
         opCount += batchList[i]->count();
     }
     DEFER_LOGD("--flushed, drew %d batches (total %d ops)", batchList.size(), opCount);
     return status;
 }

 status_t DeferredDisplayList::flush(OpenGLRenderer& renderer, Rect& dirty) {
     ATRACE_NAME("flush drawing commands");
     Caches::getInstance().fontRenderer->endPrecaching();

     status_t status = DrawGlInfo::kStatusDone;

     if (isEmpty()) return status; // nothing to flush
     renderer.restoreToCount(1);

     DEFER_LOGD("--flushing");
     renderer.eventMark("Flush");

     // save and restore (with draw modifiers) so that reordering doesn't affect final state
     DrawModifiers restoreDrawModifiers = renderer.getDrawModifiers();
     renderer.save(SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);

     // NOTE: depth of the save stack at this point, before playback, should be reflected in
     // FLUSH_SAVE_STACK_DEPTH, so that save/restores match up correctly
     status |= replayBatchList(mBatches, renderer, dirty);

     renderer.restoreToCount(1);
     renderer.setDrawModifiers(restoreDrawModifiers);

     DEFER_LOGD("--flush complete, returning %x", status);

     clear();
     return status;
 }

 }; // namespace uirenderer
 }; // namespace android
	/*
	* Copyright (C) 2013 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#define LOG_TAG "OpenGLRenderer"
	#define ATRACE_TAG ATRACE_TAG_VIEW

	#include <SkCanvas.h>

	#include <utils/Trace.h>

	#include "Caches.h"
	#include "Debug.h"
	#include "DisplayListOp.h"
	#include "OpenGLRenderer.h"

	#if DEBUG_DEFER
	#define DEFER_LOGD(...) ALOGD(__VA_ARGS__)
	#else
	#define DEFER_LOGD(...)
	#endif

	namespace android {
	namespace uirenderer {

	// Depth of the save stack at the beginning of batch playback at flush time
	#define FLUSH_SAVE_STACK_DEPTH 2

	/////////////////////////////////////////////////////////////////////////////////
	// Operation Batches
	/////////////////////////////////////////////////////////////////////////////////

	class DrawOpBatch {
	public:
	DrawOpBatch() { mOps.clear(); }

	virtual ~DrawOpBatch() { mOps.clear(); }

	void add(DrawOp* op) {
	// NOTE: ignore empty bounds special case, since we don't merge across those ops
	mBounds.unionWith(op->state.mBounds);
	mOps.add(op);
	}

	virtual bool intersects(Rect& rect) {
	if (!rect.intersects(mBounds)) return false;

	for (unsigned int i = 0; i < mOps.size(); i++) {
	if (rect.intersects(mOps[i]->state.mBounds)) {
	#if DEBUG_DEFER
	DEFER_LOGD("op intersects with op %p with bounds %f %f %f %f:", mOps[i],
	mOps[i]->state.mBounds.left, mOps[i]->state.mBounds.top,
	mOps[i]->state.mBounds.right, mOps[i]->state.mBounds.bottom);
	mOps[i]->output(2);
	#endif
	return true;
	}
	}
	return false;
	}

	virtual status_t replay(OpenGLRenderer& renderer, Rect& dirty) {
	DEFER_LOGD("replaying draw batch %p", this);

	status_t status = DrawGlInfo::kStatusDone;
	DisplayListLogBuffer& logBuffer = DisplayListLogBuffer::getInstance();
	for (unsigned int i = 0; i < mOps.size(); i++) {
	DrawOp* op = mOps[i];

	renderer.restoreDisplayState(op->state);

	#if DEBUG_DISPLAY_LIST_OPS_AS_EVENTS
	renderer.eventMark(op->name());
	#endif
	status \|= op->applyDraw(renderer, dirty, 0);
	logBuffer.writeCommand(0, op->name());
	}
	return status;
	}

	inline int count() const { return mOps.size(); }
	private:
	Vector<DrawOp*> mOps;
	Rect mBounds;
	};

	class StateOpBatch : public DrawOpBatch {
	public:
	// creates a single operation batch
	StateOpBatch(StateOp* op) : mOp(op) {}

	bool intersects(Rect& rect) {
	// if something checks for intersection, it's trying to go backwards across a state op,
	// something not currently supported - state ops are always barriers
	CRASH();
	return false;
	}

	virtual status_t replay(OpenGLRenderer& renderer, Rect& dirty) {
	DEFER_LOGD("replaying state op batch %p", this);
	renderer.restoreDisplayState(mOp->state);

	// use invalid save count because it won't be used at flush time - RestoreToCountOp is the
	// only one to use it, and we don't use that class at flush time, instead calling
	// renderer.restoreToCount directly
	int saveCount = -1;
	mOp->applyState(renderer, saveCount);
	return DrawGlInfo::kStatusDone;
	}

	private:
	const StateOp* mOp;
	};

	class RestoreToCountBatch : public DrawOpBatch {
	public:
	RestoreToCountBatch(StateOp* op, int restoreCount) : mOp(op), mRestoreCount(restoreCount) {}

	bool intersects(Rect& rect) {
	// if something checks for intersection, it's trying to go backwards across a state op,
	// something not currently supported - state ops are always barriers
	CRASH();
	return false;
	}

	virtual status_t replay(OpenGLRenderer& renderer, Rect& dirty) {
	DEFER_LOGD("batch %p restoring to count %d", this, mRestoreCount);

	renderer.restoreDisplayState(mOp->state);
	renderer.restoreToCount(mRestoreCount);
	return DrawGlInfo::kStatusDone;
	}

	private:
	// we use the state storage for the RestoreToCountOp, but don't replay the op itself
	const StateOp* mOp;
	/*
	* The count used here represents the flush() time saveCount. This is as opposed to the
	* DisplayList record time, or defer() time values (which are RestoreToCountOp's mCount, and
	* (saveCount + mCount) respectively). Since the count is different from the original
	* RestoreToCountOp, we don't store a pointer to the op, as elsewhere.
	*/
	const int mRestoreCount;
	};

	/////////////////////////////////////////////////////////////////////////////////
	// DeferredDisplayList
	/////////////////////////////////////////////////////////////////////////////////

	void DeferredDisplayList::resetBatchingState() {
	for (int i = 0; i < kOpBatch_Count; i++) {
	mBatchIndices[i] = -1;
	}
	}

	void DeferredDisplayList::clear() {
	resetBatchingState();
	mComplexClipStackStart = -1;

	for (unsigned int i = 0; i < mBatches.size(); i++) {
	delete mBatches[i];
	}
	mBatches.clear();
	mSaveStack.clear();
	}

	/////////////////////////////////////////////////////////////////////////////////
	// Operation adding
	/////////////////////////////////////////////////////////////////////////////////

	int DeferredDisplayList::getStateOpDeferFlags() const {
	// For both clipOp and save(Layer)Op, we don't want to save drawing info, and only want to save
	// the clip if we aren't recording a complex clip (and can thus trust it to be a rect)
	return recordingComplexClip() ? 0 : kStateDeferFlag_Clip;
	}

	int DeferredDisplayList::getDrawOpDeferFlags() const {
	return kStateDeferFlag_Draw \| getStateOpDeferFlags();
	}

	/**
	* When an clipping operation occurs that could cause a complex clip, record the operation and all
	* subsequent clipOps, save/restores (if the clip flag is set). During a flush, instead of loading
	* the clip from deferred state, we play back all of the relevant state operations that generated
	* the complex clip.
	*
	* Note that we don't need to record the associated restore operation, since operations at defer
	* time record whether they should store the renderer's current clip
	*/
	void DeferredDisplayList::addClip(OpenGLRenderer& renderer, ClipOp* op) {
	if (recordingComplexClip() \|\| op->canCauseComplexClip() \|\| !renderer.hasRectToRectTransform()) {
	DEFER_LOGD("%p Received complex clip operation %p", this, op);

	// NOTE: defer clip op before setting mComplexClipStackStart so previous clip is recorded
	storeStateOpBarrier(renderer, op);

	if (!recordingComplexClip()) {
	mComplexClipStackStart = renderer.getSaveCount() - 1;
	DEFER_LOGD(" Starting complex clip region, start is %d", mComplexClipStackStart);
	}
	}
	}

	/**
	* For now, we record save layer operations as barriers in the batch list, preventing drawing
	* operations from reordering around the saveLayer and it's associated restore()
	*
	* In the future, we should send saveLayer commands (if they can be played out of order) and their
	* contained drawing operations to a seperate list of batches, so that they may draw at the
	* beginning of the frame. This would avoid targetting and removing an FBO in the middle of a frame.
	*
	* saveLayer operations should be pulled to the beginning of the frame if the canvas doesn't have a
	* complex clip, and if the flags (kClip_SaveFlag & kClipToLayer_SaveFlag) are set.
	*/
	void DeferredDisplayList::addSaveLayer(OpenGLRenderer& renderer,
	SaveLayerOp* op, int newSaveCount) {
	DEFER_LOGD("%p adding saveLayerOp %p, flags %x, new count %d",
	this, op, op->getFlags(), newSaveCount);

	storeStateOpBarrier(renderer, op);
	mSaveStack.push(newSaveCount);
	}

	/**
	* Takes save op and it's return value - the new save count - and stores it into the stream as a
	* barrier if it's needed to properly modify a complex clip
	*/
	void DeferredDisplayList::addSave(OpenGLRenderer& renderer, SaveOp* op, int newSaveCount) {
	int saveFlags = op->getFlags();
	DEFER_LOGD("%p adding saveOp %p, flags %x, new count %d", this, op, saveFlags, newSaveCount);

	if (recordingComplexClip() && (saveFlags & SkCanvas::kClip_SaveFlag)) {
	// store and replay the save operation, as it may be needed to correctly playback the clip
	DEFER_LOGD(" adding save barrier with new save count %d", newSaveCount);
	storeStateOpBarrier(renderer, op);
	mSaveStack.push(newSaveCount);
	}
	}

	/**
	* saveLayer() commands must be associated with a restoreToCount batch that will clean up and draw
	* the layer in the deferred list
	*
	* other save() commands which occur as children of a snapshot with complex clip will be deferred,
	* and must be restored
	*
	* Either will act as a barrier to draw operation reordering, as we want to play back layer
	* save/restore and complex canvas modifications (including save/restore) in order.
	*/
	void DeferredDisplayList::addRestoreToCount(OpenGLRenderer& renderer, StateOp* op,
	int newSaveCount) {
	DEFER_LOGD("%p addRestoreToCount %d", this, newSaveCount);

	if (recordingComplexClip() && newSaveCount <= mComplexClipStackStart) {
	mComplexClipStackStart = -1;
	resetBatchingState();
	}

	if (mSaveStack.isEmpty() \|\| newSaveCount > mSaveStack.top()) {
	return;
	}

	while (!mSaveStack.isEmpty() && mSaveStack.top() >= newSaveCount) mSaveStack.pop();

	storeRestoreToCountBarrier(renderer, op, mSaveStack.size() + FLUSH_SAVE_STACK_DEPTH);
	}

	void DeferredDisplayList::addDrawOp(OpenGLRenderer& renderer, DrawOp* op) {
	if (renderer.storeDisplayState(op->state, getDrawOpDeferFlags())) {
	return; // quick rejected
	}

	op->onDrawOpDeferred(renderer);

	if (CC_UNLIKELY(renderer.getCaches().drawReorderDisabled)) {
	// TODO: elegant way to reuse batches?
	DrawOpBatch* b = new DrawOpBatch();
	b->add(op);
	mBatches.add(b);
	return;
	}

	// disallowReorder isn't set, so find the latest batch of the new op's type, and try to merge
	// the new op into it
	DrawOpBatch* targetBatch = NULL;
	int batchId = op->getBatchId();

	if (!mBatches.isEmpty()) {
	if (op->state.mBounds.isEmpty()) {
	// don't know the bounds for op, so add to last batch and start from scratch on next op
	mBatches.top()->add(op);
	for (int i = 0; i < kOpBatch_Count; i++) {
	mBatchIndices[i] = -1;
	}
	#if DEBUG_DEFER
	DEFER_LOGD("Warning: Encountered op with empty bounds, resetting batches");
	op->output(2);
	#endif
	return;
	}

	if (batchId >= 0 && mBatchIndices[batchId] != -1) {
	int targetIndex = mBatchIndices[batchId];
	targetBatch = mBatches[targetIndex];
	// iterate back toward target to see if anything drawn since should overlap the new op
	for (int i = mBatches.size() - 1; i > targetIndex; i--) {
	DrawOpBatch* overBatch = mBatches[i];
	if (overBatch->intersects(op->state.mBounds)) {
	targetBatch = NULL;
	#if DEBUG_DEFER
	DEFER_LOGD("op couldn't join batch %d, was intersected by batch %d",
	targetIndex, i);
	op->output(2);
	#endif
	break;
	}
	}
	}
	}
	if (!targetBatch) {
	targetBatch = new DrawOpBatch();
	mBatches.add(targetBatch);
	if (batchId >= 0) {
	mBatchIndices[batchId] = mBatches.size() - 1;
	}
	}
	targetBatch->add(op);
	}

	void DeferredDisplayList::storeStateOpBarrier(OpenGLRenderer& renderer, StateOp* op) {
	DEFER_LOGD("%p adding state op barrier at pos %d", this, mBatches.size());

	renderer.storeDisplayState(op->state, getStateOpDeferFlags());
	mBatches.add(new StateOpBatch(op));
	resetBatchingState();
	}

	void DeferredDisplayList::storeRestoreToCountBarrier(OpenGLRenderer& renderer, StateOp* op,
	int newSaveCount) {
	DEFER_LOGD("%p adding restore to count %d barrier, pos %d",
	this, newSaveCount, mBatches.size());

	// store displayState for the restore operation, as it may be associated with a saveLayer that
	// doesn't have kClip_SaveFlag set
	renderer.storeDisplayState(op->state, getStateOpDeferFlags());
	mBatches.add(new RestoreToCountBatch(op, newSaveCount));
	resetBatchingState();
	}

	/////////////////////////////////////////////////////////////////////////////////
	// Replay / flush
	/////////////////////////////////////////////////////////////////////////////////

	static status_t replayBatchList(Vector<DrawOpBatch*>& batchList,
	OpenGLRenderer& renderer, Rect& dirty) {
	status_t status = DrawGlInfo::kStatusDone;

	int opCount = 0;
	for (unsigned int i = 0; i < batchList.size(); i++) {
	status \|= batchList[i]->replay(renderer, dirty);
	opCount += batchList[i]->count();
	}
	DEFER_LOGD("--flushed, drew %d batches (total %d ops)", batchList.size(), opCount);
	return status;
	}

	status_t DeferredDisplayList::flush(OpenGLRenderer& renderer, Rect& dirty) {
	ATRACE_NAME("flush drawing commands");
	Caches::getInstance().fontRenderer->endPrecaching();

	status_t status = DrawGlInfo::kStatusDone;

	if (isEmpty()) return status; // nothing to flush
	renderer.restoreToCount(1);

	DEFER_LOGD("--flushing");
	renderer.eventMark("Flush");

	// save and restore (with draw modifiers) so that reordering doesn't affect final state
	DrawModifiers restoreDrawModifiers = renderer.getDrawModifiers();
	renderer.save(SkCanvas::kMatrix_SaveFlag \| SkCanvas::kClip_SaveFlag);

	// NOTE: depth of the save stack at this point, before playback, should be reflected in
	// FLUSH_SAVE_STACK_DEPTH, so that save/restores match up correctly
	status \|= replayBatchList(mBatches, renderer, dirty);

	renderer.restoreToCount(1);
	renderer.setDrawModifiers(restoreDrawModifiers);

	DEFER_LOGD("--flush complete, returning %x", status);

	clear();
	return status;
	}

	}; // namespace uirenderer
	}; // namespace android