/*
* 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 <ui/Rect.h>
#include <ui/Region.h>
#include "Caches.h"
#include "Debug.h"
#include "DeferredDisplayList.h"
#include "DisplayListOp.h"
#include "OpenGLRenderer.h"
#include "Properties.h"
#include "utils/MathUtils.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
#define DEBUG_COLOR_BARRIER 0x1f000000
#define DEBUG_COLOR_MERGEDBATCH 0x5f7f7fff
#define DEBUG_COLOR_MERGEDBATCH_SOLO 0x5f7fff7f
/////////////////////////////////////////////////////////////////////////////////
// Operation Batches
/////////////////////////////////////////////////////////////////////////////////
class Batch {
public:
virtual void replay(OpenGLRenderer& renderer, Rect& dirty, int index) = 0;
virtual ~Batch() {}
virtual bool purelyDrawBatch() { return false; }
virtual bool coversBounds(const Rect& bounds) { return false; }
};
class DrawBatch : public Batch {
public:
DrawBatch(const DeferInfo& deferInfo) : mAllOpsOpaque(true),
mBatchId(deferInfo.batchId), mMergeId(deferInfo.mergeId) {
mOps.clear();
}
virtual ~DrawBatch() { mOps.clear(); }
virtual void add(DrawOp* op, const DeferredDisplayState* state, bool opaqueOverBounds) {
// NOTE: ignore empty bounds special case, since we don't merge across those ops
mBounds.unionWith(state->mBounds);
mAllOpsOpaque &= opaqueOverBounds;
mOps.add(OpStatePair(op, state));
}
bool intersects(const 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].op,
mOps[i].state->mBounds.left, mOps[i].state->mBounds.top,
mOps[i].state->mBounds.right, mOps[i].state->mBounds.bottom);
mOps[i].op->output(2);
#endif
return true;
}
}
return false;
}
virtual void replay(OpenGLRenderer& renderer, Rect& dirty, int index) override {
DEFER_LOGD("%d replaying DrawBatch %p, with %d ops (batch id %x, merge id %p)",
index, this, mOps.size(), getBatchId(), getMergeId());
for (unsigned int i = 0; i < mOps.size(); i++) {
DrawOp* op = mOps[i].op;
const DeferredDisplayState* state = mOps[i].state;
renderer.restoreDisplayState(*state);
#if DEBUG_DISPLAY_LIST_OPS_AS_EVENTS
renderer.eventMark(op->name());
#endif
op->applyDraw(renderer, dirty);
#if DEBUG_MERGE_BEHAVIOR
const Rect& bounds = state->mBounds;
int batchColor = 0x1f000000;
if (getBatchId() & 0x1) batchColor |= 0x0000ff;
if (getBatchId() & 0x2) batchColor |= 0x00ff00;
if (getBatchId() & 0x4) batchColor |= 0xff0000;
renderer.drawScreenSpaceColorRect(bounds.left, bounds.top, bounds.right, bounds.bottom,
batchColor);
#endif
}
}
virtual bool purelyDrawBatch() override { return true; }
virtual bool coversBounds(const Rect& bounds) override {
if (CC_LIKELY(!mAllOpsOpaque || !mBounds.contains(bounds) || count() == 1)) return false;
Region uncovered(android::Rect(bounds.left, bounds.top, bounds.right, bounds.bottom));
for (unsigned int i = 0; i < mOps.size(); i++) {
const Rect &r = mOps[i].state->mBounds;
uncovered.subtractSelf(android::Rect(r.left, r.top, r.right, r.bottom));
}
return uncovered.isEmpty();
}
inline int getBatchId() const { return mBatchId; }
inline mergeid_t getMergeId() const { return mMergeId; }
inline int count() const { return mOps.size(); }
protected:
Vector<OpStatePair> mOps;
Rect mBounds; // union of bounds of contained ops
private:
bool mAllOpsOpaque;
int mBatchId;
mergeid_t mMergeId;
};
class MergingDrawBatch : public DrawBatch {
public:
MergingDrawBatch(DeferInfo& deferInfo, int width, int height) :
DrawBatch(deferInfo), mClipRect(width, height),
mClipSideFlags(kClipSide_None) {}
/*
* Helper for determining if a new op can merge with a MergingDrawBatch based on their bounds
* and clip side flags. Positive bounds delta means new bounds fit in old.
*/
static inline bool checkSide(const int currentFlags, const int newFlags, const int side,
float boundsDelta) {
bool currentClipExists = currentFlags & side;
bool newClipExists = newFlags & side;
// if current is clipped, we must be able to fit new bounds in current
if (boundsDelta > 0 && currentClipExists) return false;
// if new is clipped, we must be able to fit current bounds in new
if (boundsDelta < 0 && newClipExists) return false;
return true;
}
/*
* Checks if a (mergeable) op can be merged into this batch
*
* If true, the op's multiDraw must be guaranteed to handle both ops simultaneously, so it is
* important to consider all paint attributes used in the draw calls in deciding both a) if an
* op tries to merge at all, and b) if the op can merge with another set of ops
*
* False positives can lead to information from the paints of subsequent merged operations being
* dropped, so we make simplifying qualifications on the ops that can merge, per op type.
*/
bool canMergeWith(const DrawOp* op, const DeferredDisplayState* state) {
bool isTextBatch = getBatchId() == DeferredDisplayList::kOpBatch_Text ||
getBatchId() == DeferredDisplayList::kOpBatch_ColorText;
// Overlapping other operations is only allowed for text without shadow. For other ops,
// multiDraw isn't guaranteed to overdraw correctly
if (!isTextBatch || op->hasTextShadow()) {
if (intersects(state->mBounds)) return false;
}
const DeferredDisplayState* lhs = state;
const DeferredDisplayState* rhs = mOps[0].state;
if (!MathUtils::areEqual(lhs->mAlpha, rhs->mAlpha)) return false;
// Identical round rect clip state means both ops will clip in the same way, or not at all.
// As the state objects are const, we can compare their pointers to determine mergeability
if (lhs->mRoundRectClipState != rhs->mRoundRectClipState) return false;
if (lhs->mProjectionPathMask != rhs->mProjectionPathMask) return false;
/* Clipping compatibility check
*
* Exploits the fact that if a op or batch is clipped on a side, its bounds will equal its
* clip for that side.
*/
const int currentFlags = mClipSideFlags;
const int newFlags = state->mClipSideFlags;
if (currentFlags != kClipSide_None || newFlags != kClipSide_None) {
const Rect& opBounds = state->mBounds;
float boundsDelta = mBounds.left - opBounds.left;
if (!checkSide(currentFlags, newFlags, kClipSide_Left, boundsDelta)) return false;
boundsDelta = mBounds.top - opBounds.top;
if (!checkSide(currentFlags, newFlags, kClipSide_Top, boundsDelta)) return false;
// right and bottom delta calculation reversed to account for direction
boundsDelta = opBounds.right - mBounds.right;
if (!checkSide(currentFlags, newFlags, kClipSide_Right, boundsDelta)) return false;
boundsDelta = opBounds.bottom - mBounds.bottom;
if (!checkSide(currentFlags, newFlags, kClipSide_Bottom, boundsDelta)) return false;
}
// if paints are equal, then modifiers + paint attribs don't need to be compared
if (op->mPaint == mOps[0].op->mPaint) return true;
if (op->getPaintAlpha() != mOps[0].op->getPaintAlpha()) return false;
if (op->mPaint && mOps[0].op->mPaint &&
op->mPaint->getColorFilter() != mOps[0].op->mPaint->getColorFilter()) {
return false;
}
if (op->mPaint && mOps[0].op->mPaint &&
op->mPaint->getShader() != mOps[0].op->mPaint->getShader()) {
return false;
}
return true;
}
virtual void add(DrawOp* op, const DeferredDisplayState* state,
bool opaqueOverBounds) override {
DrawBatch::add(op, state, opaqueOverBounds);
const int newClipSideFlags = state->mClipSideFlags;
mClipSideFlags |= newClipSideFlags;
if (newClipSideFlags & kClipSide_Left) mClipRect.left = state->mClip.left;
if (newClipSideFlags & kClipSide_Top) mClipRect.top = state->mClip.top;
if (newClipSideFlags & kClipSide_Right) mClipRect.right = state->mClip.right;
if (newClipSideFlags & kClipSide_Bottom) mClipRect.bottom = state->mClip.bottom;
}
virtual void replay(OpenGLRenderer& renderer, Rect& dirty, int index) override {
DEFER_LOGD("%d replaying MergingDrawBatch %p, with %d ops,"
" clip flags %x (batch id %x, merge id %p)",
index, this, mOps.size(), mClipSideFlags, getBatchId(), getMergeId());
if (mOps.size() == 1) {
DrawBatch::replay(renderer, dirty, -1);
return;
}
// clipping in the merged case is done ahead of time since all ops share the clip (if any)
renderer.setupMergedMultiDraw(mClipSideFlags ? &mClipRect : nullptr);
DrawOp* op = mOps[0].op;
#if DEBUG_DISPLAY_LIST_OPS_AS_EVENTS
renderer.eventMark("multiDraw");
renderer.eventMark(op->name());
#endif
op->multiDraw(renderer, dirty, mOps, mBounds);
#if DEBUG_MERGE_BEHAVIOR
renderer.drawScreenSpaceColorRect(mBounds.left, mBounds.top, mBounds.right, mBounds.bottom,
DEBUG_COLOR_MERGEDBATCH);
#endif
}
private:
/*
* Contains the effective clip rect shared by all merged ops. Initialized to the layer viewport,
* it will shrink if an op must be clipped on a certain side. The clipped sides are reflected in
* mClipSideFlags.
*/
Rect mClipRect;
int mClipSideFlags;
};
class StateOpBatch : public Batch {
public:
// creates a single operation batch
StateOpBatch(const StateOp* op, const DeferredDisplayState* state) : mOp(op), mState(state) {}
virtual void replay(OpenGLRenderer& renderer, Rect& dirty, int index) override {
DEFER_LOGD("replaying state op batch %p", this);
renderer.restoreDisplayState(*mState);
// 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);
}
private:
const StateOp* mOp;
const DeferredDisplayState* mState;
};
class RestoreToCountBatch : public Batch {
public:
RestoreToCountBatch(const StateOp* op, const DeferredDisplayState* state, int restoreCount) :
mState(state), mRestoreCount(restoreCount) {}
virtual void replay(OpenGLRenderer& renderer, Rect& dirty, int index) override {
DEFER_LOGD("batch %p restoring to count %d", this, mRestoreCount);
renderer.restoreDisplayState(*mState);
renderer.restoreToCount(mRestoreCount);
}
private:
// we use the state storage for the RestoreToCountOp, but don't replay the op itself
const DeferredDisplayState* mState;
/*
* 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;
};
#if DEBUG_MERGE_BEHAVIOR
class BarrierDebugBatch : public Batch {
virtual void replay(OpenGLRenderer& renderer, Rect& dirty, int index) {
renderer.drawScreenSpaceColorRect(0, 0, 10000, 10000, DEBUG_COLOR_BARRIER);
}
};
#endif
/////////////////////////////////////////////////////////////////////////////////
// DeferredDisplayList
/////////////////////////////////////////////////////////////////////////////////
void DeferredDisplayList::resetBatchingState() {
for (int i = 0; i < kOpBatch_Count; i++) {
mBatchLookup[i] = nullptr;
mMergingBatches[i].clear();
}
#if DEBUG_MERGE_BEHAVIOR
if (mBatches.size() != 0) {
mBatches.add(new BarrierDebugBatch());
}
#endif
mEarliestBatchIndex = mBatches.size();
}
void DeferredDisplayList::clear() {
resetBatchingState();
mComplexClipStackStart = -1;
for (unsigned int i = 0; i < mBatches.size(); i++) {
delete mBatches[i];
}
mBatches.clear();
mSaveStack.clear();
mEarliestBatchIndex = 0;
mEarliestUnclearedIndex = 0;
}
/////////////////////////////////////////////////////////////////////////////////
// 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) {
/* 1: op calculates local bounds */
DeferredDisplayState* const state = createState();
if (op->getLocalBounds(state->mBounds)) {
if (state->mBounds.isEmpty()) {
// valid empty bounds, don't bother deferring
tryRecycleState(state);
return;
}
} else {
state->mBounds.setEmpty();
}
/* 2: renderer calculates global bounds + stores state */
if (renderer.storeDisplayState(*state, getDrawOpDeferFlags())) {
tryRecycleState(state);
return; // quick rejected
}
/* 3: ask op for defer info, given renderer state */
DeferInfo deferInfo;
op->onDefer(renderer, deferInfo, *state);
// complex clip has a complex set of expectations on the renderer state - for now, avoid taking
// the merge path in those cases
deferInfo.mergeable &= !recordingComplexClip();
deferInfo.opaqueOverBounds &= !recordingComplexClip()
&& mSaveStack.isEmpty()
&& !state->mRoundRectClipState;
if (CC_LIKELY(mAvoidOverdraw) && mBatches.size() &&
state->mClipSideFlags != kClipSide_ConservativeFull &&
deferInfo.opaqueOverBounds && state->mBounds.contains(mBounds)) {
// avoid overdraw by resetting drawing state + discarding drawing ops
discardDrawingBatches(mBatches.size() - 1);
resetBatchingState();
}
if (CC_UNLIKELY(Properties::drawReorderDisabled)) {
// TODO: elegant way to reuse batches?
DrawBatch* b = new DrawBatch(deferInfo);
b->add(op, state, deferInfo.opaqueOverBounds);
mBatches.add(b);
return;
}
// find the latest batch of the new op's type, and try to merge the new op into it
DrawBatch* targetBatch = nullptr;
// insertion point of a new batch, will hopefully be immediately after similar batch
// (eventually, should be similar shader)
int insertBatchIndex = mBatches.size();
if (!mBatches.isEmpty()) {
if (state->mBounds.isEmpty()) {
// don't know the bounds for op, so add to last batch and start from scratch on next op
DrawBatch* b = new DrawBatch(deferInfo);
b->add(op, state, deferInfo.opaqueOverBounds);
mBatches.add(b);
resetBatchingState();
#if DEBUG_DEFER
DEFER_LOGD("Warning: Encountered op with empty bounds, resetting batches");
op->output(2);
#endif
return;
}
if (deferInfo.mergeable) {
// Try to merge with any existing batch with same mergeId.
if (mMergingBatches[deferInfo.batchId].get(deferInfo.mergeId, targetBatch)) {
if (!((MergingDrawBatch*) targetBatch)->canMergeWith(op, state)) {
targetBatch = nullptr;
}
}
} else {
// join with similar, non-merging batch
targetBatch = (DrawBatch*)mBatchLookup[deferInfo.batchId];
}
if (targetBatch || deferInfo.mergeable) {
// iterate back toward target to see if anything drawn since should overlap the new op
// if no target, merging ops still interate to find similar batch to insert after
for (int i = mBatches.size() - 1; i >= mEarliestBatchIndex; i--) {
DrawBatch* overBatch = (DrawBatch*)mBatches[i];
if (overBatch == targetBatch) break;
// TODO: also consider shader shared between batch types
if (deferInfo.batchId == overBatch->getBatchId()) {
insertBatchIndex = i + 1;
if (!targetBatch) break; // found insert position, quit
}
if (overBatch->intersects(state->mBounds)) {
// NOTE: it may be possible to optimize for special cases where two operations
// of the same batch/paint could swap order, such as with a non-mergeable
// (clipped) and a mergeable text operation
targetBatch = nullptr;
#if DEBUG_DEFER
DEFER_LOGD("op couldn't join batch %p, was intersected by batch %d",
targetBatch, i);
op->output(2);
#endif
break;
}
}
}
}
if (!targetBatch) {
if (deferInfo.mergeable) {
targetBatch = new MergingDrawBatch(deferInfo,
renderer.getViewportWidth(), renderer.getViewportHeight());
mMergingBatches[deferInfo.batchId].put(deferInfo.mergeId, targetBatch);
} else {
targetBatch = new DrawBatch(deferInfo);
mBatchLookup[deferInfo.batchId] = targetBatch;
}
DEFER_LOGD("creating %singBatch %p, bid %x, at %d",
deferInfo.mergeable ? "Merg" : "Draw",
targetBatch, deferInfo.batchId, insertBatchIndex);
mBatches.insertAt(targetBatch, insertBatchIndex);
}
targetBatch->add(op, state, deferInfo.opaqueOverBounds);
}
void DeferredDisplayList::storeStateOpBarrier(OpenGLRenderer& renderer, StateOp* op) {
DEFER_LOGD("%p adding state op barrier at pos %d", this, mBatches.size());
DeferredDisplayState* state = createState();
renderer.storeDisplayState(*state, getStateOpDeferFlags());
mBatches.add(new StateOpBatch(op, state));
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
DeferredDisplayState* state = createState();
renderer.storeDisplayState(*state, getStateOpDeferFlags());
mBatches.add(new RestoreToCountBatch(op, state, newSaveCount));
resetBatchingState();
}
/////////////////////////////////////////////////////////////////////////////////
// Replay / flush
/////////////////////////////////////////////////////////////////////////////////
static void replayBatchList(const Vector<Batch*>& batchList,
OpenGLRenderer& renderer, Rect& dirty) {
for (unsigned int i = 0; i < batchList.size(); i++) {
if (batchList[i]) {
batchList[i]->replay(renderer, dirty, i);
}
}
DEFER_LOGD("--flushed, drew %d batches", batchList.size());
}
void DeferredDisplayList::flush(OpenGLRenderer& renderer, Rect& dirty) {
ATRACE_NAME("flush drawing commands");
Caches::getInstance().fontRenderer->endPrecaching();
if (isEmpty()) return; // nothing to flush
renderer.restoreToCount(1);
DEFER_LOGD("--flushing");
renderer.eventMark("Flush");
// save and restore so that reordering doesn't affect final state
renderer.save(SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
if (CC_LIKELY(mAvoidOverdraw)) {
for (unsigned int i = 1; i < mBatches.size(); i++) {
if (mBatches[i] && mBatches[i]->coversBounds(mBounds)) {
discardDrawingBatches(i - 1);
}
}
}
// 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
replayBatchList(mBatches, renderer, dirty);
renderer.restoreToCount(1);
DEFER_LOGD("--flush complete, returning %x", status);
clear();
}
void DeferredDisplayList::discardDrawingBatches(const unsigned int maxIndex) {
for (unsigned int i = mEarliestUnclearedIndex; i <= maxIndex; i++) {
// leave deferred state ops alone for simplicity (empty save restore pairs may now exist)
if (mBatches[i] && mBatches[i]->purelyDrawBatch()) {
delete mBatches[i];
mBatches.replaceAt(nullptr, i);
}
}
mEarliestUnclearedIndex = maxIndex + 1;
}
}; // namespace uirenderer
}; // namespace android