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diff --git a/gfx/skia/skia/src/utils/SkShadowUtils.cpp b/gfx/skia/skia/src/utils/SkShadowUtils.cpp
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+/*
+* Copyright 2017 Google Inc.
+*
+* Use of this source code is governed by a BSD-style license that can be
+* found in the LICENSE file.
+*/
+
+#include "include/utils/SkShadowUtils.h"
+
+#include "include/core/SkBlendMode.h"
+#include "include/core/SkBlender.h"
+#include "include/core/SkBlurTypes.h"
+#include "include/core/SkCanvas.h"
+#include "include/core/SkColorFilter.h"
+#include "include/core/SkMaskFilter.h"
+#include "include/core/SkMatrix.h"
+#include "include/core/SkPaint.h"
+#include "include/core/SkPath.h"
+#include "include/core/SkPoint.h"
+#include "include/core/SkPoint3.h"
+#include "include/core/SkRect.h"
+#include "include/core/SkRefCnt.h"
+#include "include/core/SkVertices.h"
+#include "include/private/SkIDChangeListener.h"
+#include "include/private/base/SkTPin.h"
+#include "include/private/base/SkTemplates.h"
+#include "include/private/base/SkTo.h"
+#include "src/base/SkRandom.h"
+#include "src/core/SkBlurMask.h"
+#include "src/core/SkColorFilterPriv.h"
+#include "src/core/SkDevice.h"
+#include "src/core/SkDrawShadowInfo.h"
+#include "src/core/SkPathPriv.h"
+#include "src/core/SkResourceCache.h"
+#include "src/core/SkVerticesPriv.h"
+
+#if !defined(SK_ENABLE_OPTIMIZE_SIZE)
+#include "src/utils/SkShadowTessellator.h"
+#endif
+
+#if defined(SK_GANESH)
+#include "src/gpu/ganesh/GrStyle.h"
+#include "src/gpu/ganesh/geometry/GrStyledShape.h"
+#endif
+
+#include <algorithm>
+#include <cstring>
+#include <functional>
+#include <memory>
+#include <new>
+#include <utility>
+
+using namespace skia_private;
+
+class SkRRect;
+
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
+#if !defined(SK_ENABLE_OPTIMIZE_SIZE)
+namespace {
+
+uint64_t resource_cache_shared_id() {
+ return 0x2020776f64616873llu; // 'shadow '
+}
+
+/** Factory for an ambient shadow mesh with particular shadow properties. */
+struct AmbientVerticesFactory {
+ SkScalar fOccluderHeight = SK_ScalarNaN; // NaN so that isCompatible will fail until init'ed.
+ bool fTransparent;
+ SkVector fOffset;
+
+ bool isCompatible(const AmbientVerticesFactory& that, SkVector* translate) const {
+ if (fOccluderHeight != that.fOccluderHeight || fTransparent != that.fTransparent) {
+ return false;
+ }
+ *translate = that.fOffset;
+ return true;
+ }
+
+ sk_sp<SkVertices> makeVertices(const SkPath& path, const SkMatrix& ctm,
+ SkVector* translate) const {
+ SkPoint3 zParams = SkPoint3::Make(0, 0, fOccluderHeight);
+ // pick a canonical place to generate shadow
+ SkMatrix noTrans(ctm);
+ if (!ctm.hasPerspective()) {
+ noTrans[SkMatrix::kMTransX] = 0;
+ noTrans[SkMatrix::kMTransY] = 0;
+ }
+ *translate = fOffset;
+ return SkShadowTessellator::MakeAmbient(path, noTrans, zParams, fTransparent);
+ }
+};
+
+/** Factory for an spot shadow mesh with particular shadow properties. */
+struct SpotVerticesFactory {
+ enum class OccluderType {
+ // The umbra cannot be dropped out because either the occluder is not opaque,
+ // or the center of the umbra is visible. Uses point light.
+ kPointTransparent,
+ // The umbra can be dropped where it is occluded. Uses point light.
+ kPointOpaquePartialUmbra,
+ // It is known that the entire umbra is occluded. Uses point light.
+ kPointOpaqueNoUmbra,
+ // Uses directional light.
+ kDirectional,
+ // The umbra can't be dropped out. Uses directional light.
+ kDirectionalTransparent,
+ };
+
+ SkVector fOffset;
+ SkPoint fLocalCenter;
+ SkScalar fOccluderHeight = SK_ScalarNaN; // NaN so that isCompatible will fail until init'ed.
+ SkPoint3 fDevLightPos;
+ SkScalar fLightRadius;
+ OccluderType fOccluderType;
+
+ bool isCompatible(const SpotVerticesFactory& that, SkVector* translate) const {
+ if (fOccluderHeight != that.fOccluderHeight || fDevLightPos.fZ != that.fDevLightPos.fZ ||
+ fLightRadius != that.fLightRadius || fOccluderType != that.fOccluderType) {
+ return false;
+ }
+ switch (fOccluderType) {
+ case OccluderType::kPointTransparent:
+ case OccluderType::kPointOpaqueNoUmbra:
+ // 'this' and 'that' will either both have no umbra removed or both have all the
+ // umbra removed.
+ *translate = that.fOffset;
+ return true;
+ case OccluderType::kPointOpaquePartialUmbra:
+ // In this case we partially remove the umbra differently for 'this' and 'that'
+ // if the offsets don't match.
+ if (fOffset == that.fOffset) {
+ translate->set(0, 0);
+ return true;
+ }
+ return false;
+ case OccluderType::kDirectional:
+ case OccluderType::kDirectionalTransparent:
+ *translate = that.fOffset - fOffset;
+ return true;
+ }
+ SK_ABORT("Uninitialized occluder type?");
+ }
+
+ sk_sp<SkVertices> makeVertices(const SkPath& path, const SkMatrix& ctm,
+ SkVector* translate) const {
+ bool transparent = fOccluderType == OccluderType::kPointTransparent ||
+ fOccluderType == OccluderType::kDirectionalTransparent;
+ bool directional = fOccluderType == OccluderType::kDirectional ||
+ fOccluderType == OccluderType::kDirectionalTransparent;
+ SkPoint3 zParams = SkPoint3::Make(0, 0, fOccluderHeight);
+ if (directional) {
+ translate->set(0, 0);
+ return SkShadowTessellator::MakeSpot(path, ctm, zParams, fDevLightPos, fLightRadius,
+ transparent, true);
+ } else if (ctm.hasPerspective() || OccluderType::kPointOpaquePartialUmbra == fOccluderType) {
+ translate->set(0, 0);
+ return SkShadowTessellator::MakeSpot(path, ctm, zParams, fDevLightPos, fLightRadius,
+ transparent, false);
+ } else {
+ // pick a canonical place to generate shadow, with light centered over path
+ SkMatrix noTrans(ctm);
+ noTrans[SkMatrix::kMTransX] = 0;
+ noTrans[SkMatrix::kMTransY] = 0;
+ SkPoint devCenter(fLocalCenter);
+ noTrans.mapPoints(&devCenter, 1);
+ SkPoint3 centerLightPos = SkPoint3::Make(devCenter.fX, devCenter.fY, fDevLightPos.fZ);
+ *translate = fOffset;
+ return SkShadowTessellator::MakeSpot(path, noTrans, zParams,
+ centerLightPos, fLightRadius, transparent, false);
+ }
+ }
+};
+
+/**
+ * This manages a set of tessellations for a given shape in the cache. Because SkResourceCache
+ * records are immutable this is not itself a Rec. When we need to update it we return this on
+ * the FindVisitor and let the cache destroy the Rec. We'll update the tessellations and then add
+ * a new Rec with an adjusted size for any deletions/additions.
+ */
+class CachedTessellations : public SkRefCnt {
+public:
+ size_t size() const { return fAmbientSet.size() + fSpotSet.size(); }
+
+ sk_sp<SkVertices> find(const AmbientVerticesFactory& ambient, const SkMatrix& matrix,
+ SkVector* translate) const {
+ return fAmbientSet.find(ambient, matrix, translate);
+ }
+
+ sk_sp<SkVertices> add(const SkPath& devPath, const AmbientVerticesFactory& ambient,
+ const SkMatrix& matrix, SkVector* translate) {
+ return fAmbientSet.add(devPath, ambient, matrix, translate);
+ }
+
+ sk_sp<SkVertices> find(const SpotVerticesFactory& spot, const SkMatrix& matrix,
+ SkVector* translate) const {
+ return fSpotSet.find(spot, matrix, translate);
+ }
+
+ sk_sp<SkVertices> add(const SkPath& devPath, const SpotVerticesFactory& spot,
+ const SkMatrix& matrix, SkVector* translate) {
+ return fSpotSet.add(devPath, spot, matrix, translate);
+ }
+
+private:
+ template <typename FACTORY, int MAX_ENTRIES>
+ class Set {
+ public:
+ size_t size() const { return fSize; }
+
+ sk_sp<SkVertices> find(const FACTORY& factory, const SkMatrix& matrix,
+ SkVector* translate) const {
+ for (int i = 0; i < MAX_ENTRIES; ++i) {
+ if (fEntries[i].fFactory.isCompatible(factory, translate)) {
+ const SkMatrix& m = fEntries[i].fMatrix;
+ if (matrix.hasPerspective() || m.hasPerspective()) {
+ if (matrix != fEntries[i].fMatrix) {
+ continue;
+ }
+ } else if (matrix.getScaleX() != m.getScaleX() ||
+ matrix.getSkewX() != m.getSkewX() ||
+ matrix.getScaleY() != m.getScaleY() ||
+ matrix.getSkewY() != m.getSkewY()) {
+ continue;
+ }
+ return fEntries[i].fVertices;
+ }
+ }
+ return nullptr;
+ }
+
+ sk_sp<SkVertices> add(const SkPath& path, const FACTORY& factory, const SkMatrix& matrix,
+ SkVector* translate) {
+ sk_sp<SkVertices> vertices = factory.makeVertices(path, matrix, translate);
+ if (!vertices) {
+ return nullptr;
+ }
+ int i;
+ if (fCount < MAX_ENTRIES) {
+ i = fCount++;
+ } else {
+ i = fRandom.nextULessThan(MAX_ENTRIES);
+ fSize -= fEntries[i].fVertices->approximateSize();
+ }
+ fEntries[i].fFactory = factory;
+ fEntries[i].fVertices = vertices;
+ fEntries[i].fMatrix = matrix;
+ fSize += vertices->approximateSize();
+ return vertices;
+ }
+
+ private:
+ struct Entry {
+ FACTORY fFactory;
+ sk_sp<SkVertices> fVertices;
+ SkMatrix fMatrix;
+ };
+ Entry fEntries[MAX_ENTRIES];
+ int fCount = 0;
+ size_t fSize = 0;
+ SkRandom fRandom;
+ };
+
+ Set<AmbientVerticesFactory, 4> fAmbientSet;
+ Set<SpotVerticesFactory, 4> fSpotSet;
+};
+
+/**
+ * A record of shadow vertices stored in SkResourceCache of CachedTessellations for a particular
+ * path. The key represents the path's geometry and not any shadow params.
+ */
+class CachedTessellationsRec : public SkResourceCache::Rec {
+public:
+ CachedTessellationsRec(const SkResourceCache::Key& key,
+ sk_sp<CachedTessellations> tessellations)
+ : fTessellations(std::move(tessellations)) {
+ fKey.reset(new uint8_t[key.size()]);
+ memcpy(fKey.get(), &key, key.size());
+ }
+
+ const Key& getKey() const override {
+ return *reinterpret_cast<SkResourceCache::Key*>(fKey.get());
+ }
+
+ size_t bytesUsed() const override { return fTessellations->size(); }
+
+ const char* getCategory() const override { return "tessellated shadow masks"; }
+
+ sk_sp<CachedTessellations> refTessellations() const { return fTessellations; }
+
+ template <typename FACTORY>
+ sk_sp<SkVertices> find(const FACTORY& factory, const SkMatrix& matrix,
+ SkVector* translate) const {
+ return fTessellations->find(factory, matrix, translate);
+ }
+
+private:
+ std::unique_ptr<uint8_t[]> fKey;
+ sk_sp<CachedTessellations> fTessellations;
+};
+
+/**
+ * Used by FindVisitor to determine whether a cache entry can be reused and if so returns the
+ * vertices and a translation vector. If the CachedTessellations does not contain a suitable
+ * mesh then we inform SkResourceCache to destroy the Rec and we return the CachedTessellations
+ * to the caller. The caller will update it and reinsert it back into the cache.
+ */
+template <typename FACTORY>
+struct FindContext {
+ FindContext(const SkMatrix* viewMatrix, const FACTORY* factory)
+ : fViewMatrix(viewMatrix), fFactory(factory) {}
+ const SkMatrix* const fViewMatrix;
+ // If this is valid after Find is called then we found the vertices and they should be drawn
+ // with fTranslate applied.
+ sk_sp<SkVertices> fVertices;
+ SkVector fTranslate = {0, 0};
+
+ // If this is valid after Find then the caller should add the vertices to the tessellation set
+ // and create a new CachedTessellationsRec and insert it into SkResourceCache.
+ sk_sp<CachedTessellations> fTessellationsOnFailure;
+
+ const FACTORY* fFactory;
+};
+
+/**
+ * Function called by SkResourceCache when a matching cache key is found. The FACTORY and matrix of
+ * the FindContext are used to determine if the vertices are reusable. If so the vertices and
+ * necessary translation vector are set on the FindContext.
+ */
+template <typename FACTORY>
+bool FindVisitor(const SkResourceCache::Rec& baseRec, void* ctx) {
+ FindContext<FACTORY>* findContext = (FindContext<FACTORY>*)ctx;
+ const CachedTessellationsRec& rec = static_cast<const CachedTessellationsRec&>(baseRec);
+ findContext->fVertices =
+ rec.find(*findContext->fFactory, *findContext->fViewMatrix, &findContext->fTranslate);
+ if (findContext->fVertices) {
+ return true;
+ }
+ // We ref the tessellations and let the cache destroy the Rec. Once the tessellations have been
+ // manipulated we will add a new Rec.
+ findContext->fTessellationsOnFailure = rec.refTessellations();
+ return false;
+}
+
+class ShadowedPath {
+public:
+ ShadowedPath(const SkPath* path, const SkMatrix* viewMatrix)
+ : fPath(path)
+ , fViewMatrix(viewMatrix)
+#if defined(SK_GANESH)
+ , fShapeForKey(*path, GrStyle::SimpleFill())
+#endif
+ {}
+
+ const SkPath& path() const { return *fPath; }
+ const SkMatrix& viewMatrix() const { return *fViewMatrix; }
+#if defined(SK_GANESH)
+ /** Negative means the vertices should not be cached for this path. */
+ int keyBytes() const { return fShapeForKey.unstyledKeySize() * sizeof(uint32_t); }
+ void writeKey(void* key) const {
+ fShapeForKey.writeUnstyledKey(reinterpret_cast<uint32_t*>(key));
+ }
+ bool isRRect(SkRRect* rrect) { return fShapeForKey.asRRect(rrect, nullptr, nullptr, nullptr); }
+#else
+ int keyBytes() const { return -1; }
+ void writeKey(void* key) const { SK_ABORT("Should never be called"); }
+ bool isRRect(SkRRect* rrect) { return false; }
+#endif
+
+private:
+ const SkPath* fPath;
+ const SkMatrix* fViewMatrix;
+#if defined(SK_GANESH)
+ GrStyledShape fShapeForKey;
+#endif
+};
+
+// This creates a domain of keys in SkResourceCache used by this file.
+static void* kNamespace;
+
+// When the SkPathRef genID changes, invalidate a corresponding GrResource described by key.
+class ShadowInvalidator : public SkIDChangeListener {
+public:
+ ShadowInvalidator(const SkResourceCache::Key& key) {
+ fKey.reset(new uint8_t[key.size()]);
+ memcpy(fKey.get(), &key, key.size());
+ }
+
+private:
+ const SkResourceCache::Key& getKey() const {
+ return *reinterpret_cast<SkResourceCache::Key*>(fKey.get());
+ }
+
+ // always purge
+ static bool FindVisitor(const SkResourceCache::Rec&, void*) {
+ return false;
+ }
+
+ void changed() override {
+ SkResourceCache::Find(this->getKey(), ShadowInvalidator::FindVisitor, nullptr);
+ }
+
+ std::unique_ptr<uint8_t[]> fKey;
+};
+
+/**
+ * Draws a shadow to 'canvas'. The vertices used to draw the shadow are created by 'factory' unless
+ * they are first found in SkResourceCache.
+ */
+template <typename FACTORY>
+bool draw_shadow(const FACTORY& factory,
+ std::function<void(const SkVertices*, SkBlendMode, const SkPaint&,
+ SkScalar tx, SkScalar ty, bool)> drawProc, ShadowedPath& path, SkColor color) {
+ FindContext<FACTORY> context(&path.viewMatrix(), &factory);
+
+ SkResourceCache::Key* key = nullptr;
+ AutoSTArray<32 * 4, uint8_t> keyStorage;
+ int keyDataBytes = path.keyBytes();
+ if (keyDataBytes >= 0) {
+ keyStorage.reset(keyDataBytes + sizeof(SkResourceCache::Key));
+ key = new (keyStorage.begin()) SkResourceCache::Key();
+ path.writeKey((uint32_t*)(keyStorage.begin() + sizeof(*key)));
+ key->init(&kNamespace, resource_cache_shared_id(), keyDataBytes);
+ SkResourceCache::Find(*key, FindVisitor<FACTORY>, &context);
+ }
+
+ sk_sp<SkVertices> vertices;
+ bool foundInCache = SkToBool(context.fVertices);
+ if (foundInCache) {
+ vertices = std::move(context.fVertices);
+ } else {
+ // TODO: handle transforming the path as part of the tessellator
+ if (key) {
+ // Update or initialize a tessellation set and add it to the cache.
+ sk_sp<CachedTessellations> tessellations;
+ if (context.fTessellationsOnFailure) {
+ tessellations = std::move(context.fTessellationsOnFailure);
+ } else {
+ tessellations.reset(new CachedTessellations());
+ }
+ vertices = tessellations->add(path.path(), factory, path.viewMatrix(),
+ &context.fTranslate);
+ if (!vertices) {
+ return false;
+ }
+ auto rec = new CachedTessellationsRec(*key, std::move(tessellations));
+ SkPathPriv::AddGenIDChangeListener(path.path(), sk_make_sp<ShadowInvalidator>(*key));
+ SkResourceCache::Add(rec);
+ } else {
+ vertices = factory.makeVertices(path.path(), path.viewMatrix(),
+ &context.fTranslate);
+ if (!vertices) {
+ return false;
+ }
+ }
+ }
+
+ SkPaint paint;
+ // Run the vertex color through a GaussianColorFilter and then modulate the grayscale result of
+ // that against our 'color' param.
+ paint.setColorFilter(
+ SkColorFilters::Blend(color, SkBlendMode::kModulate)->makeComposed(
+ SkColorFilterPriv::MakeGaussian()));
+
+ drawProc(vertices.get(), SkBlendMode::kModulate, paint,
+ context.fTranslate.fX, context.fTranslate.fY, path.viewMatrix().hasPerspective());
+
+ return true;
+}
+} // namespace
+
+static bool tilted(const SkPoint3& zPlaneParams) {
+ return !SkScalarNearlyZero(zPlaneParams.fX) || !SkScalarNearlyZero(zPlaneParams.fY);
+}
+#endif // SK_ENABLE_OPTIMIZE_SIZE
+
+void SkShadowUtils::ComputeTonalColors(SkColor inAmbientColor, SkColor inSpotColor,
+ SkColor* outAmbientColor, SkColor* outSpotColor) {
+ // For tonal color we only compute color values for the spot shadow.
+ // The ambient shadow is greyscale only.
+
+ // Ambient
+ *outAmbientColor = SkColorSetARGB(SkColorGetA(inAmbientColor), 0, 0, 0);
+
+ // Spot
+ int spotR = SkColorGetR(inSpotColor);
+ int spotG = SkColorGetG(inSpotColor);
+ int spotB = SkColorGetB(inSpotColor);
+ int max = std::max(std::max(spotR, spotG), spotB);
+ int min = std::min(std::min(spotR, spotG), spotB);
+ SkScalar luminance = 0.5f*(max + min)/255.f;
+ SkScalar origA = SkColorGetA(inSpotColor)/255.f;
+
+ // We compute a color alpha value based on the luminance of the color, scaled by an
+ // adjusted alpha value. We want the following properties to match the UX examples
+ // (assuming a = 0.25) and to ensure that we have reasonable results when the color
+ // is black and/or the alpha is 0:
+ // f(0, a) = 0
+ // f(luminance, 0) = 0
+ // f(1, 0.25) = .5
+ // f(0.5, 0.25) = .4
+ // f(1, 1) = 1
+ // The following functions match this as closely as possible.
+ SkScalar alphaAdjust = (2.6f + (-2.66667f + 1.06667f*origA)*origA)*origA;
+ SkScalar colorAlpha = (3.544762f + (-4.891428f + 2.3466f*luminance)*luminance)*luminance;
+ colorAlpha = SkTPin(alphaAdjust*colorAlpha, 0.0f, 1.0f);
+
+ // Similarly, we set the greyscale alpha based on luminance and alpha so that
+ // f(0, a) = a
+ // f(luminance, 0) = 0
+ // f(1, 0.25) = 0.15
+ SkScalar greyscaleAlpha = SkTPin(origA*(1 - 0.4f*luminance), 0.0f, 1.0f);
+
+ // The final color we want to emulate is generated by rendering a color shadow (C_rgb) using an
+ // alpha computed from the color's luminance (C_a), and then a black shadow with alpha (S_a)
+ // which is an adjusted value of 'a'. Assuming SrcOver, a background color of B_rgb, and
+ // ignoring edge falloff, this becomes
+ //
+ // (C_a - S_a*C_a)*C_rgb + (1 - (S_a + C_a - S_a*C_a))*B_rgb
+ //
+ // Assuming premultiplied alpha, this means we scale the color by (C_a - S_a*C_a) and
+ // set the alpha to (S_a + C_a - S_a*C_a).
+ SkScalar colorScale = colorAlpha*(SK_Scalar1 - greyscaleAlpha);
+ SkScalar tonalAlpha = colorScale + greyscaleAlpha;
+ SkScalar unPremulScale = colorScale / tonalAlpha;
+ *outSpotColor = SkColorSetARGB(tonalAlpha*255.999f,
+ unPremulScale*spotR,
+ unPremulScale*spotG,
+ unPremulScale*spotB);
+}
+
+static bool fill_shadow_rec(const SkPath& path, const SkPoint3& zPlaneParams,
+ const SkPoint3& lightPos, SkScalar lightRadius,
+ SkColor ambientColor, SkColor spotColor,
+ uint32_t flags, const SkMatrix& ctm, SkDrawShadowRec* rec) {
+ SkPoint pt = { lightPos.fX, lightPos.fY };
+ if (!SkToBool(flags & kDirectionalLight_ShadowFlag)) {
+ // If light position is in device space, need to transform to local space
+ // before applying to SkCanvas.
+ SkMatrix inverse;
+ if (!ctm.invert(&inverse)) {
+ return false;
+ }
+ inverse.mapPoints(&pt, 1);
+ }
+
+ rec->fZPlaneParams = zPlaneParams;
+ rec->fLightPos = { pt.fX, pt.fY, lightPos.fZ };
+ rec->fLightRadius = lightRadius;
+ rec->fAmbientColor = ambientColor;
+ rec->fSpotColor = spotColor;
+ rec->fFlags = flags;
+
+ return true;
+}
+
+// Draw an offset spot shadow and outlining ambient shadow for the given path.
+void SkShadowUtils::DrawShadow(SkCanvas* canvas, const SkPath& path, const SkPoint3& zPlaneParams,
+ const SkPoint3& lightPos, SkScalar lightRadius,
+ SkColor ambientColor, SkColor spotColor,
+ uint32_t flags) {
+ SkDrawShadowRec rec;
+ if (!fill_shadow_rec(path, zPlaneParams, lightPos, lightRadius, ambientColor, spotColor,
+ flags, canvas->getTotalMatrix(), &rec)) {
+ return;
+ }
+
+ canvas->private_draw_shadow_rec(path, rec);
+}
+
+bool SkShadowUtils::GetLocalBounds(const SkMatrix& ctm, const SkPath& path,
+ const SkPoint3& zPlaneParams, const SkPoint3& lightPos,
+ SkScalar lightRadius, uint32_t flags, SkRect* bounds) {
+ SkDrawShadowRec rec;
+ if (!fill_shadow_rec(path, zPlaneParams, lightPos, lightRadius, SK_ColorBLACK, SK_ColorBLACK,
+ flags, ctm, &rec)) {
+ return false;
+ }
+
+ SkDrawShadowMetrics::GetLocalBounds(path, rec, ctm, bounds);
+
+ return true;
+}
+
+//////////////////////////////////////////////////////////////////////////////////////////////
+
+static bool validate_rec(const SkDrawShadowRec& rec) {
+ return rec.fLightPos.isFinite() && rec.fZPlaneParams.isFinite() &&
+ SkScalarIsFinite(rec.fLightRadius);
+}
+
+void SkBaseDevice::drawShadow(const SkPath& path, const SkDrawShadowRec& rec) {
+ if (!validate_rec(rec)) {
+ return;
+ }
+
+ SkMatrix viewMatrix = this->localToDevice();
+ SkAutoDeviceTransformRestore adr(this, SkMatrix::I());
+
+#if !defined(SK_ENABLE_OPTIMIZE_SIZE)
+ auto drawVertsProc = [this](const SkVertices* vertices, SkBlendMode mode, const SkPaint& paint,
+ SkScalar tx, SkScalar ty, bool hasPerspective) {
+ if (vertices->priv().vertexCount()) {
+ // For perspective shadows we've already computed the shadow in world space,
+ // and we can't translate it without changing it. Otherwise we concat the
+ // change in translation from the cached version.
+ SkAutoDeviceTransformRestore adr(
+ this,
+ hasPerspective ? SkMatrix::I()
+ : this->localToDevice() * SkMatrix::Translate(tx, ty));
+ // The vertex colors for a tesselated shadow polygon are always either opaque black
+ // or transparent and their real contribution to the final blended color is via
+ // their alpha. We can skip expensive per-vertex color conversion for this.
+ this->drawVertices(vertices, SkBlender::Mode(mode), paint, /*skipColorXform=*/true);
+ }
+ };
+
+ ShadowedPath shadowedPath(&path, &viewMatrix);
+
+ bool tiltZPlane = tilted(rec.fZPlaneParams);
+ bool transparent = SkToBool(rec.fFlags & SkShadowFlags::kTransparentOccluder_ShadowFlag);
+ bool useBlur = SkToBool(rec.fFlags & SkShadowFlags::kConcaveBlurOnly_ShadowFlag) &&
+ !path.isConvex();
+ bool uncached = tiltZPlane || path.isVolatile();
+#endif
+ bool directional = SkToBool(rec.fFlags & SkShadowFlags::kDirectionalLight_ShadowFlag);
+
+ SkPoint3 zPlaneParams = rec.fZPlaneParams;
+ SkPoint3 devLightPos = rec.fLightPos;
+ if (!directional) {
+ viewMatrix.mapPoints((SkPoint*)&devLightPos.fX, 1);
+ }
+ float lightRadius = rec.fLightRadius;
+
+ if (SkColorGetA(rec.fAmbientColor) > 0) {
+ bool success = false;
+#if !defined(SK_ENABLE_OPTIMIZE_SIZE)
+ if (uncached && !useBlur) {
+ sk_sp<SkVertices> vertices = SkShadowTessellator::MakeAmbient(path, viewMatrix,
+ zPlaneParams,
+ transparent);
+ if (vertices) {
+ SkPaint paint;
+ // Run the vertex color through a GaussianColorFilter and then modulate the
+ // grayscale result of that against our 'color' param.
+ paint.setColorFilter(
+ SkColorFilters::Blend(rec.fAmbientColor,
+ SkBlendMode::kModulate)->makeComposed(
+ SkColorFilterPriv::MakeGaussian()));
+ // The vertex colors for a tesselated shadow polygon are always either opaque black
+ // or transparent and their real contribution to the final blended color is via
+ // their alpha. We can skip expensive per-vertex color conversion for this.
+ this->drawVertices(vertices.get(),
+ SkBlender::Mode(SkBlendMode::kModulate),
+ paint,
+ /*skipColorXform=*/true);
+ success = true;
+ }
+ }
+
+ if (!success && !useBlur) {
+ AmbientVerticesFactory factory;
+ factory.fOccluderHeight = zPlaneParams.fZ;
+ factory.fTransparent = transparent;
+ if (viewMatrix.hasPerspective()) {
+ factory.fOffset.set(0, 0);
+ } else {
+ factory.fOffset.fX = viewMatrix.getTranslateX();
+ factory.fOffset.fY = viewMatrix.getTranslateY();
+ }
+
+ success = draw_shadow(factory, drawVertsProc, shadowedPath, rec.fAmbientColor);
+ }
+#endif // !defined(SK_ENABLE_OPTIMIZE_SIZE)
+
+ // All else has failed, draw with blur
+ if (!success) {
+ // Pretransform the path to avoid transforming the stroke, below.
+ SkPath devSpacePath;
+ path.transform(viewMatrix, &devSpacePath);
+ devSpacePath.setIsVolatile(true);
+
+ // The tesselator outsets by AmbientBlurRadius (or 'r') to get the outer ring of
+ // the tesselation, and sets the alpha on the path to 1/AmbientRecipAlpha (or 'a').
+ //
+ // We want to emulate this with a blur. The full blur width (2*blurRadius or 'f')
+ // can be calculated by interpolating:
+ //
+ // original edge outer edge
+ // | |<---------- r ------>|
+ // |<------|--- f -------------->|
+ // | | |
+ // alpha = 1 alpha = a alpha = 0
+ //
+ // Taking ratios, f/1 = r/a, so f = r/a and blurRadius = f/2.
+ //
+ // We now need to outset the path to place the new edge in the center of the
+ // blur region:
+ //
+ // original new
+ // | |<------|--- r ------>|
+ // |<------|--- f -|------------>|
+ // | |<- o ->|<--- f/2 --->|
+ //
+ // r = o + f/2, so o = r - f/2
+ //
+ // We outset by using the stroker, so the strokeWidth is o/2.
+ //
+ SkScalar devSpaceOutset = SkDrawShadowMetrics::AmbientBlurRadius(zPlaneParams.fZ);
+ SkScalar oneOverA = SkDrawShadowMetrics::AmbientRecipAlpha(zPlaneParams.fZ);
+ SkScalar blurRadius = 0.5f*devSpaceOutset*oneOverA;
+ SkScalar strokeWidth = 0.5f*(devSpaceOutset - blurRadius);
+
+ // Now draw with blur
+ SkPaint paint;
+ paint.setColor(rec.fAmbientColor);
+ paint.setStrokeWidth(strokeWidth);
+ paint.setStyle(SkPaint::kStrokeAndFill_Style);
+ SkScalar sigma = SkBlurMask::ConvertRadiusToSigma(blurRadius);
+ bool respectCTM = false;
+ paint.setMaskFilter(SkMaskFilter::MakeBlur(kNormal_SkBlurStyle, sigma, respectCTM));
+ this->drawPath(devSpacePath, paint);
+ }
+ }
+
+ if (SkColorGetA(rec.fSpotColor) > 0) {
+ bool success = false;
+#if !defined(SK_ENABLE_OPTIMIZE_SIZE)
+ if (uncached && !useBlur) {
+ sk_sp<SkVertices> vertices = SkShadowTessellator::MakeSpot(path, viewMatrix,
+ zPlaneParams,
+ devLightPos, lightRadius,
+ transparent,
+ directional);
+ if (vertices) {
+ SkPaint paint;
+ // Run the vertex color through a GaussianColorFilter and then modulate the
+ // grayscale result of that against our 'color' param.
+ paint.setColorFilter(
+ SkColorFilters::Blend(rec.fSpotColor,
+ SkBlendMode::kModulate)->makeComposed(
+ SkColorFilterPriv::MakeGaussian()));
+ // The vertex colors for a tesselated shadow polygon are always either opaque black
+ // or transparent and their real contribution to the final blended color is via
+ // their alpha. We can skip expensive per-vertex color conversion for this.
+ this->drawVertices(vertices.get(),
+ SkBlender::Mode(SkBlendMode::kModulate),
+ paint,
+ /*skipColorXform=*/true);
+ success = true;
+ }
+ }
+
+ if (!success && !useBlur) {
+ SpotVerticesFactory factory;
+ factory.fOccluderHeight = zPlaneParams.fZ;
+ factory.fDevLightPos = devLightPos;
+ factory.fLightRadius = lightRadius;
+
+ SkPoint center = SkPoint::Make(path.getBounds().centerX(), path.getBounds().centerY());
+ factory.fLocalCenter = center;
+ viewMatrix.mapPoints(&center, 1);
+ SkScalar radius, scale;
+ if (SkToBool(rec.fFlags & kDirectionalLight_ShadowFlag)) {
+ SkDrawShadowMetrics::GetDirectionalParams(zPlaneParams.fZ, devLightPos.fX,
+ devLightPos.fY, devLightPos.fZ,
+ lightRadius, &radius, &scale,
+ &factory.fOffset);
+ } else {
+ SkDrawShadowMetrics::GetSpotParams(zPlaneParams.fZ, devLightPos.fX - center.fX,
+ devLightPos.fY - center.fY, devLightPos.fZ,
+ lightRadius, &radius, &scale, &factory.fOffset);
+ }
+
+ SkRect devBounds;
+ viewMatrix.mapRect(&devBounds, path.getBounds());
+ if (transparent ||
+ SkTAbs(factory.fOffset.fX) > 0.5f*devBounds.width() ||
+ SkTAbs(factory.fOffset.fY) > 0.5f*devBounds.height()) {
+ // if the translation of the shadow is big enough we're going to end up
+ // filling the entire umbra, we can treat these as all the same
+ if (directional) {
+ factory.fOccluderType =
+ SpotVerticesFactory::OccluderType::kDirectionalTransparent;
+ } else {
+ factory.fOccluderType = SpotVerticesFactory::OccluderType::kPointTransparent;
+ }
+ } else if (directional) {
+ factory.fOccluderType = SpotVerticesFactory::OccluderType::kDirectional;
+ } else if (factory.fOffset.length()*scale + scale < radius) {
+ // if we don't translate more than the blur distance, can assume umbra is covered
+ factory.fOccluderType = SpotVerticesFactory::OccluderType::kPointOpaqueNoUmbra;
+ } else if (path.isConvex()) {
+ factory.fOccluderType = SpotVerticesFactory::OccluderType::kPointOpaquePartialUmbra;
+ } else {
+ factory.fOccluderType = SpotVerticesFactory::OccluderType::kPointTransparent;
+ }
+ // need to add this after we classify the shadow
+ factory.fOffset.fX += viewMatrix.getTranslateX();
+ factory.fOffset.fY += viewMatrix.getTranslateY();
+
+ SkColor color = rec.fSpotColor;
+#ifdef DEBUG_SHADOW_CHECKS
+ switch (factory.fOccluderType) {
+ case SpotVerticesFactory::OccluderType::kPointTransparent:
+ color = 0xFFD2B48C; // tan for transparent
+ break;
+ case SpotVerticesFactory::OccluderType::kPointOpaquePartialUmbra:
+ color = 0xFFFFA500; // orange for opaque
+ break;
+ case SpotVerticesFactory::OccluderType::kPointOpaqueNoUmbra:
+ color = 0xFFE5E500; // corn yellow for covered
+ break;
+ case SpotVerticesFactory::OccluderType::kDirectional:
+ case SpotVerticesFactory::OccluderType::kDirectionalTransparent:
+ color = 0xFF550000; // dark red for directional
+ break;
+ }
+#endif
+ success = draw_shadow(factory, drawVertsProc, shadowedPath, color);
+ }
+#endif // !defined(SK_ENABLE_OPTIMIZE_SIZE)
+
+ // All else has failed, draw with blur
+ if (!success) {
+ SkMatrix shadowMatrix;
+ SkScalar radius;
+ if (!SkDrawShadowMetrics::GetSpotShadowTransform(devLightPos, lightRadius,
+ viewMatrix, zPlaneParams,
+ path.getBounds(), directional,
+ &shadowMatrix, &radius)) {
+ return;
+ }
+ SkAutoDeviceTransformRestore adr2(this, shadowMatrix);
+
+ SkPaint paint;
+ paint.setColor(rec.fSpotColor);
+ SkScalar sigma = SkBlurMask::ConvertRadiusToSigma(radius);
+ bool respectCTM = false;
+ paint.setMaskFilter(SkMaskFilter::MakeBlur(kNormal_SkBlurStyle, sigma, respectCTM));
+ this->drawPath(path, paint);
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-09 03:01:35 +0000