| /* |
| * Copyright 2014 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkRecordOpts.h" |
| |
| #include "SkRecordPattern.h" |
| #include "SkRecords.h" |
| #include "SkTDArray.h" |
| |
| using namespace SkRecords; |
| |
| void SkRecordOptimize(SkRecord* record) { |
| // TODO(mtklein): fuse independent optimizations to reduce number of passes? |
| SkRecordNoopCulls(record); |
| SkRecordNoopSaveRestores(record); |
| // TODO(mtklein): figure out why we draw differently and reenable |
| //SkRecordNoopSaveLayerDrawRestores(record); |
| |
| SkRecordAnnotateCullingPairs(record); |
| SkRecordReduceDrawPosTextStrength(record); // Helpful to run this before BoundDrawPosTextH. |
| SkRecordBoundDrawPosTextH(record); |
| } |
| |
| // Most of the optimizations in this file are pattern-based. These are all defined as structs with: |
| // - a Pattern typedef |
| // - a bool onMatch(SkRceord*, Pattern*, unsigned begin, unsigned end) method, |
| // which returns true if it made changes and false if not. |
| |
| // Run a pattern-based optimization once across the SkRecord, returning true if it made any changes. |
| // It looks for spans which match Pass::Pattern, and when found calls onMatch() with the pattern, |
| // record, and [begin,end) span of the commands that matched. |
| template <typename Pass> |
| static bool apply(Pass* pass, SkRecord* record) { |
| typename Pass::Pattern pattern; |
| bool changed = false; |
| unsigned begin, end = 0; |
| |
| while (pattern.search(record, &begin, &end)) { |
| changed |= pass->onMatch(record, &pattern, begin, end); |
| } |
| return changed; |
| } |
| |
| struct CullNooper { |
| typedef Pattern3<Is<PushCull>, Star<Is<NoOp> >, Is<PopCull> > Pattern; |
| |
| bool onMatch(SkRecord* record, Pattern* pattern, unsigned begin, unsigned end) { |
| record->replace<NoOp>(begin); // PushCull |
| record->replace<NoOp>(end-1); // PopCull |
| return true; |
| } |
| }; |
| |
| void SkRecordNoopCulls(SkRecord* record) { |
| CullNooper pass; |
| while (apply(&pass, record)); |
| } |
| |
| // Turns the logical NoOp Save and Restore in Save-Draw*-Restore patterns into actual NoOps. |
| struct SaveOnlyDrawsRestoreNooper { |
| typedef Pattern3<Is<Save>, |
| Star<Or<Is<NoOp>, IsDraw> >, |
| Is<Restore> > |
| Pattern; |
| |
| bool onMatch(SkRecord* record, Pattern* pattern, unsigned begin, unsigned end) { |
| record->replace<NoOp>(begin); // Save |
| record->replace<NoOp>(end-1); // Restore |
| return true; |
| } |
| }; |
| // Turns logical no-op Save-[non-drawing command]*-Restore patterns into actual no-ops. |
| struct SaveNoDrawsRestoreNooper { |
| // Star matches greedily, so we also have to exclude Save and Restore. |
| typedef Pattern3<Is<Save>, |
| Star<Not<Or3<Is<Save>, |
| Is<Restore>, |
| IsDraw> > >, |
| Is<Restore> > |
| Pattern; |
| |
| bool onMatch(SkRecord* record, Pattern* pattern, unsigned begin, unsigned end) { |
| // If restore doesn't revert both matrix and clip, this isn't safe to noop away. |
| if (pattern->first<Save>()->flags != SkCanvas::kMatrixClip_SaveFlag) { |
| return false; |
| } |
| |
| // The entire span between Save and Restore (inclusively) does nothing. |
| for (unsigned i = begin; i < end; i++) { |
| record->replace<NoOp>(i); |
| } |
| return true; |
| } |
| }; |
| void SkRecordNoopSaveRestores(SkRecord* record) { |
| SaveOnlyDrawsRestoreNooper onlyDraws; |
| SaveNoDrawsRestoreNooper noDraws; |
| |
| // Run until they stop changing things. |
| while (apply(&onlyDraws, record) || apply(&noDraws, record)); |
| } |
| |
| // For some SaveLayer-[drawing command]-Restore patterns, merge the SaveLayer's alpha into the |
| // draw, and no-op the SaveLayer and Restore. |
| struct SaveLayerDrawRestoreNooper { |
| typedef Pattern3<Is<SaveLayer>, IsDraw, Is<Restore> > Pattern; |
| |
| bool onMatch(SkRecord* record, Pattern* pattern, unsigned begin, unsigned end) { |
| SaveLayer* saveLayer = pattern->first<SaveLayer>(); |
| if (saveLayer->bounds != NULL) { |
| // SaveLayer with bounds is too tricky for us. |
| return false; |
| } |
| |
| SkPaint* layerPaint = saveLayer->paint; |
| if (NULL == layerPaint) { |
| // There wasn't really any point to this SaveLayer at all. |
| return KillSaveLayerAndRestore(record, begin); |
| } |
| |
| SkPaint* drawPaint = pattern->second<SkPaint>(); |
| if (drawPaint == NULL) { |
| // We can just give the draw the SaveLayer's paint. |
| // TODO(mtklein): figure out how to do this clearly |
| return false; |
| } |
| |
| const uint32_t layerColor = layerPaint->getColor(); |
| const uint32_t drawColor = drawPaint->getColor(); |
| if (!IsOnlyAlpha(layerColor) || !IsOpaque(drawColor) || |
| HasAnyEffect(*layerPaint) || HasAnyEffect(*drawPaint)) { |
| // Too fancy for us. Actually, as long as layerColor is just an alpha |
| // we can blend it into drawColor's alpha; drawColor doesn't strictly have to be opaque. |
| return false; |
| } |
| |
| drawPaint->setColor(SkColorSetA(drawColor, SkColorGetA(layerColor))); |
| return KillSaveLayerAndRestore(record, begin); |
| } |
| |
| static bool KillSaveLayerAndRestore(SkRecord* record, unsigned saveLayerIndex) { |
| record->replace<NoOp>(saveLayerIndex); // SaveLayer |
| record->replace<NoOp>(saveLayerIndex+2); // Restore |
| return true; |
| } |
| |
| static bool HasAnyEffect(const SkPaint& paint) { |
| return paint.getPathEffect() || |
| paint.getShader() || |
| paint.getXfermode() || |
| paint.getMaskFilter() || |
| paint.getColorFilter() || |
| paint.getRasterizer() || |
| paint.getLooper() || |
| paint.getImageFilter(); |
| } |
| |
| static bool IsOpaque(SkColor color) { |
| return SkColorGetA(color) == SK_AlphaOPAQUE; |
| } |
| static bool IsOnlyAlpha(SkColor color) { |
| return SK_ColorTRANSPARENT == SkColorSetA(color, SK_AlphaTRANSPARENT); |
| } |
| }; |
| void SkRecordNoopSaveLayerDrawRestores(SkRecord* record) { |
| SaveLayerDrawRestoreNooper pass; |
| apply(&pass, record); |
| } |
| |
| |
| // Replaces DrawPosText with DrawPosTextH when all Y coordinates are equal. |
| struct StrengthReducer { |
| typedef Pattern1<Is<DrawPosText> > Pattern; |
| |
| bool onMatch(SkRecord* record, Pattern* pattern, unsigned begin, unsigned end) { |
| SkASSERT(end == begin + 1); |
| DrawPosText* draw = pattern->first<DrawPosText>(); |
| |
| const unsigned points = draw->paint.countText(draw->text, draw->byteLength); |
| if (points == 0) { |
| return false; // No point (ha!). |
| } |
| |
| const SkScalar firstY = draw->pos[0].fY; |
| for (unsigned i = 1; i < points; i++) { |
| if (draw->pos[i].fY != firstY) { |
| return false; // Needs full power of DrawPosText. |
| } |
| } |
| // All ys are the same. We can replace DrawPosText with DrawPosTextH. |
| |
| // draw->pos is points SkPoints, [(x,y),(x,y),(x,y),(x,y), ... ]. |
| // We're going to squint and look at that as 2*points SkScalars, [x,y,x,y,x,y,x,y, ...]. |
| // Then we'll rearrange things so all the xs are in order up front, clobbering the ys. |
| SK_COMPILE_ASSERT(sizeof(SkPoint) == 2 * sizeof(SkScalar), SquintingIsNotSafe); |
| SkScalar* scalars = &draw->pos[0].fX; |
| for (unsigned i = 0; i < 2*points; i += 2) { |
| scalars[i/2] = scalars[i]; |
| } |
| |
| // Extend lifetime of draw to the end of the loop so we can copy its paint. |
| Adopted<DrawPosText> adopted(draw); |
| SkNEW_PLACEMENT_ARGS(record->replace<DrawPosTextH>(begin, adopted), |
| DrawPosTextH, |
| (draw->paint, draw->text, draw->byteLength, scalars, firstY)); |
| return true; |
| } |
| }; |
| void SkRecordReduceDrawPosTextStrength(SkRecord* record) { |
| StrengthReducer pass; |
| apply(&pass, record); |
| } |
| |
| // Tries to replace DrawPosTextH with BoundedDrawPosTextH, which knows conservative upper and lower |
| // bounds to use with SkCanvas::quickRejectY. |
| struct TextBounder { |
| typedef Pattern1<Is<DrawPosTextH> > Pattern; |
| |
| bool onMatch(SkRecord* record, Pattern* pattern, unsigned begin, unsigned end) { |
| SkASSERT(end == begin + 1); |
| DrawPosTextH* draw = pattern->first<DrawPosTextH>(); |
| |
| // If we're drawing vertical text, none of the checks we're about to do make any sense. |
| // We'll need to call SkPaint::computeFastBounds() later, so bail if that's not possible. |
| if (draw->paint.isVerticalText() || !draw->paint.canComputeFastBounds()) { |
| return false; |
| } |
| |
| // Rather than checking the top and bottom font metrics, we guess. Actually looking up the |
| // top and bottom metrics is slow, and this overapproximation should be good enough. |
| const SkScalar buffer = draw->paint.getTextSize() * 1.5f; |
| SkDEBUGCODE(SkPaint::FontMetrics metrics;) |
| SkDEBUGCODE(draw->paint.getFontMetrics(&metrics);) |
| SkASSERT(-buffer <= metrics.fTop); |
| SkASSERT(+buffer >= metrics.fBottom); |
| |
| // Let the paint adjust the text bounds. We don't care about left and right here, so we use |
| // 0 and 1 respectively just so the bounds rectangle isn't empty. |
| SkRect bounds; |
| bounds.set(0, draw->y - buffer, SK_Scalar1, draw->y + buffer); |
| SkRect adjusted = draw->paint.computeFastBounds(bounds, &bounds); |
| |
| Adopted<DrawPosTextH> adopted(draw); |
| SkNEW_PLACEMENT_ARGS(record->replace<BoundedDrawPosTextH>(begin, adopted), |
| BoundedDrawPosTextH, |
| (&adopted, adjusted.fTop, adjusted.fBottom)); |
| return true; |
| } |
| }; |
| void SkRecordBoundDrawPosTextH(SkRecord* record) { |
| TextBounder pass; |
| apply(&pass, record); |
| } |
| |
| // Replaces PushCull with PairedPushCull, which lets us skip to the paired PopCull when the canvas |
| // can quickReject the cull rect. |
| // There's no efficient way (yet?) to express this one as a pattern, so we write a custom pass. |
| class CullAnnotator { |
| public: |
| // Do nothing to most ops. |
| template <typename T> void operator()(T*) {} |
| |
| void operator()(PushCull* push) { |
| Pair pair = { fIndex, push }; |
| fPushStack.push(pair); |
| } |
| |
| void operator()(PopCull* pop) { |
| Pair push = fPushStack.top(); |
| fPushStack.pop(); |
| |
| SkASSERT(fIndex > push.index); |
| unsigned skip = fIndex - push.index; |
| |
| Adopted<PushCull> adopted(push.command); |
| SkNEW_PLACEMENT_ARGS(fRecord->replace<PairedPushCull>(push.index, adopted), |
| PairedPushCull, (&adopted, skip)); |
| } |
| |
| void apply(SkRecord* record) { |
| for (fRecord = record, fIndex = 0; fIndex < record->count(); fIndex++) { |
| fRecord->mutate<void>(fIndex, *this); |
| } |
| } |
| |
| private: |
| struct Pair { |
| unsigned index; |
| PushCull* command; |
| }; |
| |
| SkTDArray<Pair> fPushStack; |
| SkRecord* fRecord; |
| unsigned fIndex; |
| }; |
| void SkRecordAnnotateCullingPairs(SkRecord* record) { |
| CullAnnotator pass; |
| pass.apply(record); |
| } |