1 /*
2  * Copyright 2018 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #include "GrCCDrawPathsOp.h"
9 
10 #include "GrContext.h"
11 #include "GrContextPriv.h"
12 #include "GrMemoryPool.h"
13 #include "GrOpFlushState.h"
14 #include "ccpr/GrCCPathCache.h"
15 #include "ccpr/GrCCPerFlushResources.h"
16 #include "ccpr/GrCoverageCountingPathRenderer.h"
17 
has_coord_transforms(const GrPaint & paint)18 static bool has_coord_transforms(const GrPaint& paint) {
19     GrFragmentProcessor::Iter iter(paint);
20     while (const GrFragmentProcessor* fp = iter.next()) {
21         if (!fp->coordTransforms().empty()) {
22             return true;
23         }
24     }
25     return false;
26 }
27 
Make(GrContext * context,const SkIRect & clipIBounds,const SkMatrix & m,const GrShape & shape,GrPaint && paint)28 std::unique_ptr<GrCCDrawPathsOp> GrCCDrawPathsOp::Make(
29         GrContext* context, const SkIRect& clipIBounds, const SkMatrix& m, const GrShape& shape,
30         GrPaint&& paint) {
31     SkRect conservativeDevBounds;
32     m.mapRect(&conservativeDevBounds, shape.bounds());
33 
34     const SkStrokeRec& stroke = shape.style().strokeRec();
35     float strokeDevWidth = 0;
36     float conservativeInflationRadius = 0;
37     if (!stroke.isFillStyle()) {
38         strokeDevWidth = GrCoverageCountingPathRenderer::GetStrokeDevWidth(
39                 m, stroke, &conservativeInflationRadius);
40         conservativeDevBounds.outset(conservativeInflationRadius, conservativeInflationRadius);
41     }
42 
43     std::unique_ptr<GrCCDrawPathsOp> op;
44     float conservativeSize = SkTMax(conservativeDevBounds.height(), conservativeDevBounds.width());
45     if (conservativeSize > GrCoverageCountingPathRenderer::kPathCropThreshold) {
46         // The path is too large. Crop it or analytic AA can run out of fp32 precision.
47         SkPath croppedDevPath;
48         shape.asPath(&croppedDevPath);
49         croppedDevPath.transform(m, &croppedDevPath);
50 
51         SkIRect cropBox = clipIBounds;
52         GrShape croppedDevShape;
53         if (stroke.isFillStyle()) {
54             GrCoverageCountingPathRenderer::CropPath(croppedDevPath, cropBox, &croppedDevPath);
55             croppedDevShape = GrShape(croppedDevPath);
56             conservativeDevBounds = croppedDevShape.bounds();
57         } else {
58             int r = SkScalarCeilToInt(conservativeInflationRadius);
59             cropBox.outset(r, r);
60             GrCoverageCountingPathRenderer::CropPath(croppedDevPath, cropBox, &croppedDevPath);
61             SkStrokeRec devStroke = stroke;
62             devStroke.setStrokeStyle(strokeDevWidth);
63             croppedDevShape = GrShape(croppedDevPath, GrStyle(devStroke, nullptr));
64             conservativeDevBounds = croppedDevPath.getBounds();
65             conservativeDevBounds.outset(conservativeInflationRadius, conservativeInflationRadius);
66         }
67 
68         // FIXME: This breaks local coords: http://skbug.com/8003
69         return InternalMake(context, clipIBounds, SkMatrix::I(), croppedDevShape, strokeDevWidth,
70                             conservativeDevBounds, std::move(paint));
71     }
72 
73     return InternalMake(context, clipIBounds, m, shape, strokeDevWidth, conservativeDevBounds,
74                         std::move(paint));
75 }
76 
InternalMake(GrContext * context,const SkIRect & clipIBounds,const SkMatrix & m,const GrShape & shape,float strokeDevWidth,const SkRect & conservativeDevBounds,GrPaint && paint)77 std::unique_ptr<GrCCDrawPathsOp> GrCCDrawPathsOp::InternalMake(
78         GrContext* context, const SkIRect& clipIBounds, const SkMatrix& m, const GrShape& shape,
79         float strokeDevWidth, const SkRect& conservativeDevBounds, GrPaint&& paint) {
80     // The path itself should have been cropped if larger than kPathCropThreshold. If it had a
81     // stroke, that would have further inflated its draw bounds.
82     SkASSERT(SkTMax(conservativeDevBounds.height(), conservativeDevBounds.width()) <
83              GrCoverageCountingPathRenderer::kPathCropThreshold +
84              GrCoverageCountingPathRenderer::kMaxBoundsInflationFromStroke*2 + 1);
85 
86     SkIRect shapeConservativeIBounds;
87     conservativeDevBounds.roundOut(&shapeConservativeIBounds);
88 
89     SkIRect maskDevIBounds;
90     if (!maskDevIBounds.intersect(clipIBounds, shapeConservativeIBounds)) {
91         return nullptr;
92     }
93 
94     GrOpMemoryPool* pool = context->contextPriv().opMemoryPool();
95     return pool->allocate<GrCCDrawPathsOp>(m, shape, strokeDevWidth, shapeConservativeIBounds,
96                                            maskDevIBounds, conservativeDevBounds, std::move(paint));
97 }
98 
GrCCDrawPathsOp(const SkMatrix & m,const GrShape & shape,float strokeDevWidth,const SkIRect & shapeConservativeIBounds,const SkIRect & maskDevIBounds,const SkRect & conservativeDevBounds,GrPaint && paint)99 GrCCDrawPathsOp::GrCCDrawPathsOp(const SkMatrix& m, const GrShape& shape, float strokeDevWidth,
100                                  const SkIRect& shapeConservativeIBounds,
101                                  const SkIRect& maskDevIBounds, const SkRect& conservativeDevBounds,
102                                  GrPaint&& paint)
103         : GrDrawOp(ClassID())
104         , fViewMatrixIfUsingLocalCoords(has_coord_transforms(paint) ? m : SkMatrix::I())
105         , fDraws(m, shape, strokeDevWidth, shapeConservativeIBounds, maskDevIBounds,
106                  paint.getColor4f())
107         , fProcessors(std::move(paint)) {  // Paint must be moved after fetching its color above.
108     SkDEBUGCODE(fBaseInstance = -1);
109     // FIXME: intersect with clip bounds to (hopefully) improve batching.
110     // (This is nontrivial due to assumptions in generating the octagon cover geometry.)
111     this->setBounds(conservativeDevBounds, GrOp::HasAABloat::kYes, GrOp::IsZeroArea::kNo);
112 }
113 
~GrCCDrawPathsOp()114 GrCCDrawPathsOp::~GrCCDrawPathsOp() {
115     if (fOwningPerOpListPaths) {
116         // Remove the list's dangling pointer to this Op before deleting it.
117         fOwningPerOpListPaths->fDrawOps.remove(this);
118     }
119 }
120 
SingleDraw(const SkMatrix & m,const GrShape & shape,float strokeDevWidth,const SkIRect & shapeConservativeIBounds,const SkIRect & maskDevIBounds,const SkPMColor4f & color)121 GrCCDrawPathsOp::SingleDraw::SingleDraw(const SkMatrix& m, const GrShape& shape,
122                                         float strokeDevWidth,
123                                         const SkIRect& shapeConservativeIBounds,
124                                         const SkIRect& maskDevIBounds, const SkPMColor4f& color)
125         : fMatrix(m)
126         , fShape(shape)
127         , fStrokeDevWidth(strokeDevWidth)
128         , fShapeConservativeIBounds(shapeConservativeIBounds)
129         , fMaskDevIBounds(maskDevIBounds)
130         , fColor(color) {
131 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
132     if (fShape.hasUnstyledKey()) {
133         // On AOSP we round view matrix translates to integer values for cachable paths. We do this
134         // to match HWUI's cache hit ratio, which doesn't consider the matrix when caching paths.
135         fMatrix.setTranslateX(SkScalarRoundToScalar(fMatrix.getTranslateX()));
136         fMatrix.setTranslateY(SkScalarRoundToScalar(fMatrix.getTranslateY()));
137     }
138 #endif
139 }
140 
finalize(const GrCaps & caps,const GrAppliedClip * clip)141 GrProcessorSet::Analysis GrCCDrawPathsOp::finalize(const GrCaps& caps, const GrAppliedClip* clip) {
142     SkASSERT(1 == fNumDraws);  // There should only be one single path draw in this Op right now.
143     return fDraws.head().finalize(caps, clip, &fProcessors);
144 }
145 
finalize(const GrCaps & caps,const GrAppliedClip * clip,GrProcessorSet * processors)146 GrProcessorSet::Analysis GrCCDrawPathsOp::SingleDraw::finalize(
147         const GrCaps& caps, const GrAppliedClip* clip, GrProcessorSet* processors) {
148     const GrProcessorSet::Analysis& analysis = processors->finalize(
149             fColor, GrProcessorAnalysisCoverage::kSingleChannel, clip, false, caps,
150             &fColor);
151 
152     // Lines start looking jagged when they get thinner than 1px. For thin strokes it looks better
153     // if we can convert them to hairline (i.e., inflate the stroke width to 1px), and instead
154     // reduce the opacity to create the illusion of thin-ness. This strategy also helps reduce
155     // artifacts from coverage dilation when there are self intersections.
156     if (analysis.isCompatibleWithCoverageAsAlpha() &&
157             !fShape.style().strokeRec().isFillStyle() && fStrokeDevWidth < 1) {
158         // Modifying the shape affects its cache key. The draw can't have a cache entry yet or else
159         // our next step would invalidate it.
160         SkASSERT(!fCacheEntry);
161         SkASSERT(SkStrokeRec::kStroke_Style == fShape.style().strokeRec().getStyle());
162 
163         SkPath path;
164         fShape.asPath(&path);
165 
166         // Create a hairline version of our stroke.
167         SkStrokeRec hairlineStroke = fShape.style().strokeRec();
168         hairlineStroke.setStrokeStyle(0);
169 
170         // How transparent does a 1px stroke have to be in order to appear as thin as the real one?
171         float coverage = fStrokeDevWidth;
172 
173         fShape = GrShape(path, GrStyle(hairlineStroke, nullptr));
174         fStrokeDevWidth = 1;
175 
176         // fShapeConservativeIBounds already accounted for this possibility of inflating the stroke.
177         fColor = fColor * coverage;
178     }
179 
180     return analysis;
181 }
182 
onCombineIfPossible(GrOp * op,const GrCaps &)183 GrOp::CombineResult GrCCDrawPathsOp::onCombineIfPossible(GrOp* op, const GrCaps&) {
184     GrCCDrawPathsOp* that = op->cast<GrCCDrawPathsOp>();
185     SkASSERT(fOwningPerOpListPaths);
186     SkASSERT(fNumDraws);
187     SkASSERT(!that->fOwningPerOpListPaths || that->fOwningPerOpListPaths == fOwningPerOpListPaths);
188     SkASSERT(that->fNumDraws);
189 
190     if (fProcessors != that->fProcessors ||
191         fViewMatrixIfUsingLocalCoords != that->fViewMatrixIfUsingLocalCoords) {
192         return CombineResult::kCannotCombine;
193     }
194 
195     fDraws.append(std::move(that->fDraws), &fOwningPerOpListPaths->fAllocator);
196 
197     SkDEBUGCODE(fNumDraws += that->fNumDraws);
198     SkDEBUGCODE(that->fNumDraws = 0);
199     return CombineResult::kMerged;
200 }
201 
addToOwningPerOpListPaths(sk_sp<GrCCPerOpListPaths> owningPerOpListPaths)202 void GrCCDrawPathsOp::addToOwningPerOpListPaths(sk_sp<GrCCPerOpListPaths> owningPerOpListPaths) {
203     SkASSERT(1 == fNumDraws);
204     SkASSERT(!fOwningPerOpListPaths);
205     fOwningPerOpListPaths = std::move(owningPerOpListPaths);
206     fOwningPerOpListPaths->fDrawOps.addToTail(this);
207 }
208 
accountForOwnPaths(GrCCPathCache * pathCache,GrOnFlushResourceProvider * onFlushRP,GrCCPerFlushResourceSpecs * specs)209 void GrCCDrawPathsOp::accountForOwnPaths(GrCCPathCache* pathCache,
210                                          GrOnFlushResourceProvider* onFlushRP,
211                                          GrCCPerFlushResourceSpecs* specs) {
212     for (SingleDraw& draw : fDraws) {
213         draw.accountForOwnPath(pathCache, onFlushRP, specs);
214     }
215 }
216 
accountForOwnPath(GrCCPathCache * pathCache,GrOnFlushResourceProvider * onFlushRP,GrCCPerFlushResourceSpecs * specs)217 void GrCCDrawPathsOp::SingleDraw::accountForOwnPath(
218         GrCCPathCache* pathCache, GrOnFlushResourceProvider* onFlushRP,
219         GrCCPerFlushResourceSpecs* specs) {
220     using CoverageType = GrCCAtlas::CoverageType;
221 
222     SkPath path;
223     fShape.asPath(&path);
224 
225     SkASSERT(!fCacheEntry);
226 
227     if (pathCache) {
228         fCacheEntry =
229                 pathCache->find(onFlushRP, fShape, fMaskDevIBounds, fMatrix, &fCachedMaskShift);
230     }
231 
232     if (fCacheEntry) {
233         if (const GrCCCachedAtlas* cachedAtlas = fCacheEntry->cachedAtlas()) {
234             SkASSERT(cachedAtlas->getOnFlushProxy());
235             if (CoverageType::kA8_LiteralCoverage == cachedAtlas->coverageType()) {
236                 ++specs->fNumCachedPaths;
237             } else {
238                 // Suggest that this path be copied to a literal coverage atlas, to save memory.
239                 // (The client may decline this copy via DoCopiesToA8Coverage::kNo.)
240                 int idx = (fShape.style().strokeRec().isFillStyle())
241                         ? GrCCPerFlushResourceSpecs::kFillIdx
242                         : GrCCPerFlushResourceSpecs::kStrokeIdx;
243                 ++specs->fNumCopiedPaths[idx];
244                 specs->fCopyPathStats[idx].statPath(path);
245                 specs->fCopyAtlasSpecs.accountForSpace(fCacheEntry->width(), fCacheEntry->height());
246                 fDoCopyToA8Coverage = true;
247             }
248             return;
249         }
250 
251         if (this->shouldCachePathMask(onFlushRP->caps()->maxRenderTargetSize())) {
252             fDoCachePathMask = true;
253             // We don't cache partial masks; ensure the bounds include the entire path.
254             fMaskDevIBounds = fShapeConservativeIBounds;
255         }
256     }
257 
258     // Plan on rendering this path in a new atlas.
259     int idx = (fShape.style().strokeRec().isFillStyle())
260             ? GrCCPerFlushResourceSpecs::kFillIdx
261             : GrCCPerFlushResourceSpecs::kStrokeIdx;
262     ++specs->fNumRenderedPaths[idx];
263     specs->fRenderedPathStats[idx].statPath(path);
264     specs->fRenderedAtlasSpecs.accountForSpace(fMaskDevIBounds.width(), fMaskDevIBounds.height());
265 }
266 
shouldCachePathMask(int maxRenderTargetSize) const267 bool GrCCDrawPathsOp::SingleDraw::shouldCachePathMask(int maxRenderTargetSize) const {
268     SkASSERT(fCacheEntry);
269     SkASSERT(!fCacheEntry->cachedAtlas());
270     if (fCacheEntry->hitCount() <= 1) {
271         return false;  // Don't cache a path mask until at least its second hit.
272     }
273 
274     int shapeMaxDimension = SkTMax(fShapeConservativeIBounds.height(),
275                                    fShapeConservativeIBounds.width());
276     if (shapeMaxDimension > maxRenderTargetSize) {
277         return false;  // This path isn't cachable.
278     }
279 
280     int64_t shapeArea = sk_64_mul(fShapeConservativeIBounds.height(),
281                                   fShapeConservativeIBounds.width());
282     if (shapeArea < 100*100) {
283         // If a path is small enough, we might as well try to render and cache the entire thing, no
284         // matter how much of it is actually visible.
285         return true;
286     }
287 
288     // The hitRect should already be contained within the shape's bounds, but we still intersect it
289     // because it's possible for edges very near pixel boundaries (e.g., 0.999999), to round out
290     // inconsistently, depending on the integer translation values and fp32 precision.
291     SkIRect hitRect = fCacheEntry->hitRect().makeOffset(fCachedMaskShift.x(), fCachedMaskShift.y());
292     hitRect.intersect(fShapeConservativeIBounds);
293 
294     // Render and cache the entire path mask if we see enough of it to justify rendering all the
295     // pixels. Our criteria for "enough" is that we must have seen at least 50% of the path in the
296     // past, and in this particular draw we must see at least 10% of it.
297     int64_t hitArea = sk_64_mul(hitRect.height(), hitRect.width());
298     int64_t drawArea = sk_64_mul(fMaskDevIBounds.height(), fMaskDevIBounds.width());
299     return hitArea*2 >= shapeArea && drawArea*10 >= shapeArea;
300 }
301 
setupResources(GrCCPathCache * pathCache,GrOnFlushResourceProvider * onFlushRP,GrCCPerFlushResources * resources,DoCopiesToA8Coverage doCopies)302 void GrCCDrawPathsOp::setupResources(
303         GrCCPathCache* pathCache, GrOnFlushResourceProvider* onFlushRP,
304         GrCCPerFlushResources* resources, DoCopiesToA8Coverage doCopies) {
305     SkASSERT(fNumDraws > 0);
306     SkASSERT(-1 == fBaseInstance);
307     fBaseInstance = resources->nextPathInstanceIdx();
308 
309     for (SingleDraw& draw : fDraws) {
310         draw.setupResources(pathCache, onFlushRP, resources, doCopies, this);
311     }
312 
313     if (!fInstanceRanges.empty()) {
314         fInstanceRanges.back().fEndInstanceIdx = resources->nextPathInstanceIdx();
315     }
316 }
317 
setupResources(GrCCPathCache * pathCache,GrOnFlushResourceProvider * onFlushRP,GrCCPerFlushResources * resources,DoCopiesToA8Coverage doCopies,GrCCDrawPathsOp * op)318 void GrCCDrawPathsOp::SingleDraw::setupResources(
319         GrCCPathCache* pathCache, GrOnFlushResourceProvider* onFlushRP,
320         GrCCPerFlushResources* resources, DoCopiesToA8Coverage doCopies, GrCCDrawPathsOp* op) {
321     using DoEvenOddFill = GrCCPathProcessor::DoEvenOddFill;
322 
323     SkPath path;
324     fShape.asPath(&path);
325 
326     auto doEvenOddFill = DoEvenOddFill(fShape.style().strokeRec().isFillStyle() &&
327                                        SkPath::kEvenOdd_FillType == path.getFillType());
328     SkASSERT(SkPath::kEvenOdd_FillType == path.getFillType() ||
329              SkPath::kWinding_FillType == path.getFillType());
330 
331     if (fCacheEntry) {
332         // Does the path already exist in a cached atlas texture?
333         if (fCacheEntry->cachedAtlas()) {
334             SkASSERT(fCacheEntry->cachedAtlas()->getOnFlushProxy());
335             if (DoCopiesToA8Coverage::kYes == doCopies && fDoCopyToA8Coverage) {
336                 resources->upgradeEntryToLiteralCoverageAtlas(pathCache, onFlushRP,
337                                                               fCacheEntry.get(), doEvenOddFill);
338                 SkASSERT(fCacheEntry->cachedAtlas());
339                 SkASSERT(GrCCAtlas::CoverageType::kA8_LiteralCoverage
340                                  == fCacheEntry->cachedAtlas()->coverageType());
341                 SkASSERT(fCacheEntry->cachedAtlas()->getOnFlushProxy());
342             }
343 #if 0
344             // Simple color manipulation to visualize cached paths.
345             fColor = (GrCCAtlas::CoverageType::kA8_LiteralCoverage
346                               == fCacheEntry->cachedAtlas()->coverageType())
347                     ? SkPMColor4f{0,0,.25,.25} : SkPMColor4f{0,.25,0,.25};
348 #endif
349             op->recordInstance(fCacheEntry->cachedAtlas()->getOnFlushProxy(),
350                                resources->nextPathInstanceIdx());
351             resources->appendDrawPathInstance().set(*fCacheEntry, fCachedMaskShift,
352                                                     SkPMColor4f_toFP16(fColor));
353             return;
354         }
355     }
356 
357     // Render the raw path into a coverage count atlas. renderShapeInAtlas() gives us two tight
358     // bounding boxes: One in device space, as well as a second one rotated an additional 45
359     // degrees. The path vertex shader uses these two bounding boxes to generate an octagon that
360     // circumscribes the path.
361     SkRect devBounds, devBounds45;
362     SkIRect devIBounds;
363     SkIVector devToAtlasOffset;
364     if (auto atlas = resources->renderShapeInAtlas(
365                 fMaskDevIBounds, fMatrix, fShape, fStrokeDevWidth, &devBounds, &devBounds45,
366                 &devIBounds, &devToAtlasOffset)) {
367         op->recordInstance(atlas->textureProxy(), resources->nextPathInstanceIdx());
368         resources->appendDrawPathInstance().set(devBounds, devBounds45, devToAtlasOffset,
369                                                 SkPMColor4f_toFP16(fColor), doEvenOddFill);
370 
371         if (fDoCachePathMask) {
372             SkASSERT(fCacheEntry);
373             SkASSERT(!fCacheEntry->cachedAtlas());
374             SkASSERT(fShapeConservativeIBounds == fMaskDevIBounds);
375             fCacheEntry->setCoverageCountAtlas(onFlushRP, atlas, devToAtlasOffset, devBounds,
376                                                devBounds45, devIBounds, fCachedMaskShift);
377         }
378     }
379 }
380 
recordInstance(GrTextureProxy * atlasProxy,int instanceIdx)381 inline void GrCCDrawPathsOp::recordInstance(GrTextureProxy* atlasProxy, int instanceIdx) {
382     if (fInstanceRanges.empty()) {
383         fInstanceRanges.push_back({atlasProxy, instanceIdx});
384         return;
385     }
386     if (fInstanceRanges.back().fAtlasProxy != atlasProxy) {
387         fInstanceRanges.back().fEndInstanceIdx = instanceIdx;
388         fInstanceRanges.push_back({atlasProxy, instanceIdx});
389         return;
390     }
391 }
392 
onExecute(GrOpFlushState * flushState,const SkRect & chainBounds)393 void GrCCDrawPathsOp::onExecute(GrOpFlushState* flushState, const SkRect& chainBounds) {
394     SkASSERT(fOwningPerOpListPaths);
395 
396     const GrCCPerFlushResources* resources = fOwningPerOpListPaths->fFlushResources.get();
397     if (!resources) {
398         return;  // Setup failed.
399     }
400 
401     GrPipeline::InitArgs initArgs;
402     initArgs.fCaps = &flushState->caps();
403     initArgs.fResourceProvider = flushState->resourceProvider();
404     initArgs.fDstProxy = flushState->drawOpArgs().fDstProxy;
405     auto clip = flushState->detachAppliedClip();
406     GrPipeline::FixedDynamicState fixedDynamicState(clip.scissorState().rect());
407     GrPipeline pipeline(initArgs, std::move(fProcessors), std::move(clip));
408 
409     int baseInstance = fBaseInstance;
410     SkASSERT(baseInstance >= 0);  // Make sure setupResources() has been called.
411 
412     for (const InstanceRange& range : fInstanceRanges) {
413         SkASSERT(range.fEndInstanceIdx > baseInstance);
414 
415         GrCCPathProcessor pathProc(range.fAtlasProxy, fViewMatrixIfUsingLocalCoords);
416         GrTextureProxy* atlasProxy = range.fAtlasProxy;
417         fixedDynamicState.fPrimitiveProcessorTextures = &atlasProxy;
418         pathProc.drawPaths(flushState, pipeline, &fixedDynamicState, *resources, baseInstance,
419                            range.fEndInstanceIdx, this->bounds());
420 
421         baseInstance = range.fEndInstanceIdx;
422     }
423 }
424