/* * Copyright 2016 Google Inc. * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ #ifndef GrStyle_DEFINED #define GrStyle_DEFINED #include "GrTypes.h" #include "SkPathEffect.h" #include "SkStrokeRec.h" #include "SkTemplates.h" /** * Represents the various ways that a GrShape can be styled. It has fill/stroking information * as well as an optional path effect. If the path effect represents dashing, the dashing * information is extracted from the path effect and stored explicitly. * * This will replace GrStrokeInfo as GrShape is deployed. */ class GrStyle { public: /** * A style object that represents a fill with no path effect. * TODO: constexpr with C++14 */ static const GrStyle& SimpleFill() { static const GrStyle kFill(SkStrokeRec::kFill_InitStyle); return kFill; } /** * A style object that represents a hairline stroke with no path effect. * TODO: constexpr with C++14 */ static const GrStyle& SimpleHairline() { static const GrStyle kHairline(SkStrokeRec::kHairline_InitStyle); return kHairline; } enum class Apply { kPathEffectOnly, kPathEffectAndStrokeRec }; /** * Optional flags for computing keys that may remove unnecessary variation in the key due to * style settings that don't affect particular classes of geometry. */ enum KeyFlags { // The shape being styled has no open contours. kClosed_KeyFlag = 0x1, // The shape being styled doesn't have any joins and so isn't affected by join type. kNoJoins_KeyFlag = 0x2 }; /** * Computes the key length for a GrStyle. The return will be negative if it cannot be turned * into a key. This occurs when there is a path effect that is not a dash. The key can * either reflect just the path effect (if one) or the path effect and the strokerec. Note * that a simple fill has a zero sized key. */ static int KeySize(const GrStyle&, Apply, uint32_t flags = 0); /** * Writes a unique key for the style into the provided buffer. This function assumes the buffer * has room for at least KeySize() values. It assumes that KeySize() returns a non-negative * value for the combination of GrStyle, Apply and flags params. This is written so that the key * for just dash application followed by the key for the remaining SkStrokeRec is the same as * the key for applying dashing and SkStrokeRec all at once. */ static void WriteKey(uint32_t*, const GrStyle&, Apply, SkScalar scale, uint32_t flags = 0); GrStyle() : GrStyle(SkStrokeRec::kFill_InitStyle) {} explicit GrStyle(SkStrokeRec::InitStyle initStyle) : fStrokeRec(initStyle) {} GrStyle(const SkStrokeRec& strokeRec, sk_sp pe) : fStrokeRec(strokeRec) { this->initPathEffect(std::move(pe)); } GrStyle(const GrStyle& that) = default; explicit GrStyle(const SkPaint& paint) : fStrokeRec(paint) { this->initPathEffect(paint.refPathEffect()); } explicit GrStyle(const SkPaint& paint, SkPaint::Style overrideStyle) : fStrokeRec(paint, overrideStyle) { this->initPathEffect(paint.refPathEffect()); } GrStyle& operator=(const GrStyle& that) { fPathEffect = that.fPathEffect; fDashInfo = that.fDashInfo; fStrokeRec = that.fStrokeRec; return *this; } void resetToInitStyle(SkStrokeRec::InitStyle fillOrHairline) { fDashInfo.reset(); fPathEffect.reset(nullptr); if (SkStrokeRec::kFill_InitStyle == fillOrHairline) { fStrokeRec.setFillStyle(); } else { fStrokeRec.setHairlineStyle(); } } /** Is this style a fill with no path effect? */ bool isSimpleFill() const { return fStrokeRec.isFillStyle() && !fPathEffect; } /** Is this style a hairline with no path effect? */ bool isSimpleHairline() const { return fStrokeRec.isHairlineStyle() && !fPathEffect; } SkPathEffect* pathEffect() const { return fPathEffect.get(); } sk_sp refPathEffect() const { return fPathEffect; } bool hasPathEffect() const { return SkToBool(fPathEffect.get()); } bool hasNonDashPathEffect() const { return fPathEffect.get() && !this->isDashed(); } bool isDashed() const { return SkPathEffect::kDash_DashType == fDashInfo.fType; } SkScalar dashPhase() const { SkASSERT(this->isDashed()); return fDashInfo.fPhase; } int dashIntervalCnt() const { SkASSERT(this->isDashed()); return fDashInfo.fIntervals.count(); } const SkScalar* dashIntervals() const { SkASSERT(this->isDashed()); return fDashInfo.fIntervals.get(); } const SkStrokeRec& strokeRec() const { return fStrokeRec; } /** Hairline or fill styles without path effects make no alterations to a geometry. */ bool applies() const { return this->pathEffect() || (!fStrokeRec.isFillStyle() && !fStrokeRec.isHairlineStyle()); } static SkScalar MatrixToScaleFactor(const SkMatrix& matrix) { // getMaxScale will return -1 if the matrix has perspective. In that case we can use a scale // factor of 1. This isn't necessarily a good choice and in the future we might consider // taking a bounds here for the perspective case. return SkScalarAbs(matrix.getMaxScale()); } /** * Applies just the path effect and returns remaining stroke information. This will fail if * there is no path effect. dst may or may not have been overwritten on failure. Scale controls * geometric approximations made by the path effect. It is typically computed from the view * matrix. */ bool SK_WARN_UNUSED_RESULT applyPathEffectToPath(SkPath* dst, SkStrokeRec* remainingStoke, const SkPath& src, SkScalar scale) const; /** * If this succeeds then the result path should be filled or hairlined as indicated by the * returned SkStrokeRec::InitStyle value. Will fail if there is no path effect and the * strokerec doesn't change the geometry. When this fails the outputs may or may not have * been overwritten. Scale controls geometric approximations made by the path effect and * stroker. It is typically computed from the view matrix. */ bool SK_WARN_UNUSED_RESULT applyToPath(SkPath* dst, SkStrokeRec::InitStyle* fillOrHairline, const SkPath& src, SkScalar scale) const; /** Given bounds of a path compute the bounds of path with the style applied. */ void adjustBounds(SkRect* dst, const SkRect& src) const { if (this->pathEffect()) { this->pathEffect()->computeFastBounds(dst, src); // This may not be the correct SkStrokeRec to use. skbug.com/5299 // It happens to work for dashing. SkScalar radius = fStrokeRec.getInflationRadius(); dst->outset(radius, radius); } else { SkScalar radius = fStrokeRec.getInflationRadius(); *dst = src.makeOutset(radius, radius); } } private: void initPathEffect(sk_sp pe); struct DashInfo { DashInfo() : fType(SkPathEffect::kNone_DashType) {} DashInfo(const DashInfo& that) { *this = that; } DashInfo& operator=(const DashInfo& that) { fType = that.fType; fPhase = that.fPhase; fIntervals.reset(that.fIntervals.count()); sk_careful_memcpy(fIntervals.get(), that.fIntervals.get(), sizeof(SkScalar) * that.fIntervals.count()); return *this; } void reset() { fType = SkPathEffect::kNone_DashType; fIntervals.reset(0); } SkPathEffect::DashType fType; SkScalar fPhase; SkAutoSTArray<4, SkScalar> fIntervals; }; bool applyPathEffect(SkPath* dst, SkStrokeRec* strokeRec, const SkPath& src) const; SkStrokeRec fStrokeRec; sk_sp fPathEffect; DashInfo fDashInfo; }; #endif