| /* |
| * Copyright 2006 The Android Open Source Project |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "include/core/SkPath.h" |
| |
| #include "include/core/SkData.h" |
| #include "include/core/SkMath.h" |
| #include "include/core/SkRRect.h" |
| #include "include/private/SkMacros.h" |
| #include "include/private/SkPathRef.h" |
| #include "include/private/SkTo.h" |
| #include "src/core/SkBuffer.h" |
| #include "src/core/SkCubicClipper.h" |
| #include "src/core/SkGeometry.h" |
| #include "src/core/SkMatrixPriv.h" |
| #include "src/core/SkPathMakers.h" |
| #include "src/core/SkPathPriv.h" |
| #include "src/core/SkPointPriv.h" |
| #include "src/core/SkSafeMath.h" |
| #include "src/core/SkTLazy.h" |
| // need SkDVector |
| #include "src/pathops/SkPathOpsPoint.h" |
| |
| #include <cmath> |
| #include <utility> |
| |
| struct SkPath_Storage_Equivalent { |
| void* fPtr; |
| int32_t fIndex; |
| uint32_t fFlags; |
| }; |
| |
| static_assert(sizeof(SkPath) == sizeof(SkPath_Storage_Equivalent), |
| "Please keep an eye on SkPath packing."); |
| |
| static float poly_eval(float A, float B, float C, float t) { |
| return (A * t + B) * t + C; |
| } |
| |
| static float poly_eval(float A, float B, float C, float D, float t) { |
| return ((A * t + B) * t + C) * t + D; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| /** |
| * Path.bounds is defined to be the bounds of all the control points. |
| * If we called bounds.join(r) we would skip r if r was empty, which breaks |
| * our promise. Hence we have a custom joiner that doesn't look at emptiness |
| */ |
| static void joinNoEmptyChecks(SkRect* dst, const SkRect& src) { |
| dst->fLeft = SkMinScalar(dst->fLeft, src.fLeft); |
| dst->fTop = SkMinScalar(dst->fTop, src.fTop); |
| dst->fRight = SkMaxScalar(dst->fRight, src.fRight); |
| dst->fBottom = SkMaxScalar(dst->fBottom, src.fBottom); |
| } |
| |
| static bool is_degenerate(const SkPath& path) { |
| return path.countVerbs() <= 1; |
| } |
| |
| class SkAutoDisableDirectionCheck { |
| public: |
| SkAutoDisableDirectionCheck(SkPath* path) : fPath(path) { |
| fSaved = static_cast<SkPathPriv::FirstDirection>(fPath->getFirstDirection()); |
| } |
| |
| ~SkAutoDisableDirectionCheck() { |
| fPath->setFirstDirection(fSaved); |
| } |
| |
| private: |
| SkPath* fPath; |
| SkPathPriv::FirstDirection fSaved; |
| }; |
| #define SkAutoDisableDirectionCheck(...) SK_REQUIRE_LOCAL_VAR(SkAutoDisableDirectionCheck) |
| |
| /* This guy's constructor/destructor bracket a path editing operation. It is |
| used when we know the bounds of the amount we are going to add to the path |
| (usually a new contour, but not required). |
| |
| It captures some state about the path up front (i.e. if it already has a |
| cached bounds), and then if it can, it updates the cache bounds explicitly, |
| avoiding the need to revisit all of the points in getBounds(). |
| |
| It also notes if the path was originally degenerate, and if so, sets |
| isConvex to true. Thus it can only be used if the contour being added is |
| convex. |
| */ |
| class SkAutoPathBoundsUpdate { |
| public: |
| SkAutoPathBoundsUpdate(SkPath* path, const SkRect& r) : fPath(path), fRect(r) { |
| // Cannot use fRect for our bounds unless we know it is sorted |
| fRect.sort(); |
| // Mark the path's bounds as dirty if (1) they are, or (2) the path |
| // is non-finite, and therefore its bounds are not meaningful |
| fHasValidBounds = path->hasComputedBounds() && path->isFinite(); |
| fEmpty = path->isEmpty(); |
| if (fHasValidBounds && !fEmpty) { |
| joinNoEmptyChecks(&fRect, fPath->getBounds()); |
| } |
| fDegenerate = is_degenerate(*path); |
| } |
| |
| ~SkAutoPathBoundsUpdate() { |
| fPath->setConvexity(fDegenerate ? SkPath::kConvex_Convexity |
| : SkPath::kUnknown_Convexity); |
| if ((fEmpty || fHasValidBounds) && fRect.isFinite()) { |
| fPath->setBounds(fRect); |
| } |
| } |
| |
| private: |
| SkPath* fPath; |
| SkRect fRect; |
| bool fHasValidBounds; |
| bool fDegenerate; |
| bool fEmpty; |
| }; |
| #define SkAutoPathBoundsUpdate(...) SK_REQUIRE_LOCAL_VAR(SkAutoPathBoundsUpdate) |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| /* |
| Stores the verbs and points as they are given to us, with exceptions: |
| - we only record "Close" if it was immediately preceeded by Move | Line | Quad | Cubic |
| - we insert a Move(0,0) if Line | Quad | Cubic is our first command |
| |
| The iterator does more cleanup, especially if forceClose == true |
| 1. If we encounter degenerate segments, remove them |
| 2. if we encounter Close, return a cons'd up Line() first (if the curr-pt != start-pt) |
| 3. if we encounter Move without a preceeding Close, and forceClose is true, goto #2 |
| 4. if we encounter Line | Quad | Cubic after Close, cons up a Move |
| */ |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| // flag to require a moveTo if we begin with something else, like lineTo etc. |
| #define INITIAL_LASTMOVETOINDEX_VALUE ~0 |
| |
| SkPath::SkPath() |
| : fPathRef(SkPathRef::CreateEmpty()) { |
| this->resetFields(); |
| fIsVolatile = false; |
| } |
| |
| void SkPath::resetFields() { |
| //fPathRef is assumed to have been emptied by the caller. |
| fLastMoveToIndex = INITIAL_LASTMOVETOINDEX_VALUE; |
| fFillType = kWinding_FillType; |
| this->setConvexity(kUnknown_Convexity); |
| this->setFirstDirection(SkPathPriv::kUnknown_FirstDirection); |
| |
| // We don't touch Android's fSourcePath. It's used to track texture garbage collection, so we |
| // don't want to muck with it if it's been set to something non-nullptr. |
| } |
| |
| SkPath::SkPath(const SkPath& that) |
| : fPathRef(SkRef(that.fPathRef.get())) { |
| this->copyFields(that); |
| SkDEBUGCODE(that.validate();) |
| } |
| |
| SkPath::~SkPath() { |
| SkDEBUGCODE(this->validate();) |
| } |
| |
| SkPath& SkPath::operator=(const SkPath& that) { |
| SkDEBUGCODE(that.validate();) |
| |
| if (this != &that) { |
| fPathRef.reset(SkRef(that.fPathRef.get())); |
| this->copyFields(that); |
| } |
| SkDEBUGCODE(this->validate();) |
| return *this; |
| } |
| |
| void SkPath::copyFields(const SkPath& that) { |
| //fPathRef is assumed to have been set by the caller. |
| fLastMoveToIndex = that.fLastMoveToIndex; |
| fFillType = that.fFillType; |
| fIsVolatile = that.fIsVolatile; |
| |
| // Non-atomic assignment of atomic values. |
| this->setConvexity(that.getConvexityOrUnknown()); |
| this->setFirstDirection(that.getFirstDirection()); |
| } |
| |
| bool operator==(const SkPath& a, const SkPath& b) { |
| // note: don't need to look at isConvex or bounds, since just comparing the |
| // raw data is sufficient. |
| return &a == &b || |
| (a.fFillType == b.fFillType && *a.fPathRef.get() == *b.fPathRef.get()); |
| } |
| |
| void SkPath::swap(SkPath& that) { |
| if (this != &that) { |
| fPathRef.swap(that.fPathRef); |
| std::swap(fLastMoveToIndex, that.fLastMoveToIndex); |
| |
| const auto ft = fFillType; |
| fFillType = that.fFillType; |
| that.fFillType = ft; |
| |
| const auto iv = fIsVolatile; |
| fIsVolatile = that.fIsVolatile; |
| that.fIsVolatile = iv; |
| |
| // Non-atomic swaps of atomic values. |
| Convexity c = this->getConvexityOrUnknown(); |
| this->setConvexity(that.getConvexityOrUnknown()); |
| that.setConvexity(c); |
| |
| uint8_t fd = this->getFirstDirection(); |
| this->setFirstDirection(that.getFirstDirection()); |
| that.setFirstDirection(fd); |
| } |
| } |
| |
| bool SkPath::isInterpolatable(const SkPath& compare) const { |
| // need the same structure (verbs, conicweights) and same point-count |
| return fPathRef->fPoints.count() == compare.fPathRef->fPoints.count() && |
| fPathRef->fVerbs == compare.fPathRef->fVerbs && |
| fPathRef->fConicWeights == compare.fPathRef->fConicWeights; |
| } |
| |
| bool SkPath::interpolate(const SkPath& ending, SkScalar weight, SkPath* out) const { |
| int pointCount = fPathRef->countPoints(); |
| if (pointCount != ending.fPathRef->countPoints()) { |
| return false; |
| } |
| if (!pointCount) { |
| return true; |
| } |
| out->reset(); |
| out->addPath(*this); |
| fPathRef->interpolate(*ending.fPathRef, weight, out->fPathRef.get()); |
| return true; |
| } |
| |
| static inline bool check_edge_against_rect(const SkPoint& p0, |
| const SkPoint& p1, |
| const SkRect& rect, |
| SkPathPriv::FirstDirection dir) { |
| const SkPoint* edgeBegin; |
| SkVector v; |
| if (SkPathPriv::kCW_FirstDirection == dir) { |
| v = p1 - p0; |
| edgeBegin = &p0; |
| } else { |
| v = p0 - p1; |
| edgeBegin = &p1; |
| } |
| if (v.fX || v.fY) { |
| // check the cross product of v with the vec from edgeBegin to each rect corner |
| SkScalar yL = v.fY * (rect.fLeft - edgeBegin->fX); |
| SkScalar xT = v.fX * (rect.fTop - edgeBegin->fY); |
| SkScalar yR = v.fY * (rect.fRight - edgeBegin->fX); |
| SkScalar xB = v.fX * (rect.fBottom - edgeBegin->fY); |
| if ((xT < yL) || (xT < yR) || (xB < yL) || (xB < yR)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| bool SkPath::conservativelyContainsRect(const SkRect& rect) const { |
| // This only handles non-degenerate convex paths currently. |
| if (kConvex_Convexity != this->getConvexity()) { |
| return false; |
| } |
| |
| SkPathPriv::FirstDirection direction; |
| if (!SkPathPriv::CheapComputeFirstDirection(*this, &direction)) { |
| return false; |
| } |
| |
| SkPoint firstPt; |
| SkPoint prevPt; |
| SkPath::Iter iter(*this, true); |
| SkPath::Verb verb; |
| SkPoint pts[4]; |
| int segmentCount = 0; |
| SkDEBUGCODE(int moveCnt = 0;) |
| SkDEBUGCODE(int closeCount = 0;) |
| |
| while ((verb = iter.next(pts)) != kDone_Verb) { |
| int nextPt = -1; |
| switch (verb) { |
| case kMove_Verb: |
| SkASSERT(!segmentCount && !closeCount); |
| SkDEBUGCODE(++moveCnt); |
| firstPt = prevPt = pts[0]; |
| break; |
| case kLine_Verb: |
| if (!SkPathPriv::AllPointsEq(pts, 2)) { |
| nextPt = 1; |
| SkASSERT(moveCnt && !closeCount); |
| ++segmentCount; |
| } |
| break; |
| case kQuad_Verb: |
| case kConic_Verb: |
| if (!SkPathPriv::AllPointsEq(pts, 3)) { |
| SkASSERT(moveCnt && !closeCount); |
| ++segmentCount; |
| nextPt = 2; |
| } |
| break; |
| case kCubic_Verb: |
| if (!SkPathPriv::AllPointsEq(pts, 4)) { |
| SkASSERT(moveCnt && !closeCount); |
| ++segmentCount; |
| nextPt = 3; |
| } |
| break; |
| case kClose_Verb: |
| SkDEBUGCODE(++closeCount;) |
| break; |
| default: |
| SkDEBUGFAIL("unknown verb"); |
| } |
| if (-1 != nextPt) { |
| if (SkPath::kConic_Verb == verb) { |
| SkConic orig; |
| orig.set(pts, iter.conicWeight()); |
| SkPoint quadPts[5]; |
| int count = orig.chopIntoQuadsPOW2(quadPts, 1); |
| SkASSERT_RELEASE(2 == count); |
| |
| if (!check_edge_against_rect(quadPts[0], quadPts[2], rect, direction)) { |
| return false; |
| } |
| if (!check_edge_against_rect(quadPts[2], quadPts[4], rect, direction)) { |
| return false; |
| } |
| } else { |
| if (!check_edge_against_rect(prevPt, pts[nextPt], rect, direction)) { |
| return false; |
| } |
| } |
| prevPt = pts[nextPt]; |
| } |
| } |
| |
| if (segmentCount) { |
| return check_edge_against_rect(prevPt, firstPt, rect, direction); |
| } |
| return false; |
| } |
| |
| uint32_t SkPath::getGenerationID() const { |
| uint32_t genID = fPathRef->genID(); |
| #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK |
| SkASSERT((unsigned)fFillType < (1 << (32 - SkPathPriv::kPathRefGenIDBitCnt))); |
| genID |= static_cast<uint32_t>(fFillType) << SkPathPriv::kPathRefGenIDBitCnt; |
| #endif |
| return genID; |
| } |
| |
| SkPath& SkPath::reset() { |
| SkDEBUGCODE(this->validate();) |
| |
| fPathRef.reset(SkPathRef::CreateEmpty()); |
| this->resetFields(); |
| return *this; |
| } |
| |
| SkPath& SkPath::rewind() { |
| SkDEBUGCODE(this->validate();) |
| |
| SkPathRef::Rewind(&fPathRef); |
| this->resetFields(); |
| return *this; |
| } |
| |
| bool SkPath::isLastContourClosed() const { |
| int verbCount = fPathRef->countVerbs(); |
| if (0 == verbCount) { |
| return false; |
| } |
| return kClose_Verb == fPathRef->atVerb(verbCount - 1); |
| } |
| |
| bool SkPath::isLine(SkPoint line[2]) const { |
| int verbCount = fPathRef->countVerbs(); |
| |
| if (2 == verbCount) { |
| SkASSERT(kMove_Verb == fPathRef->atVerb(0)); |
| if (kLine_Verb == fPathRef->atVerb(1)) { |
| SkASSERT(2 == fPathRef->countPoints()); |
| if (line) { |
| const SkPoint* pts = fPathRef->points(); |
| line[0] = pts[0]; |
| line[1] = pts[1]; |
| } |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /* |
| Determines if path is a rect by keeping track of changes in direction |
| and looking for a loop either clockwise or counterclockwise. |
| |
| The direction is computed such that: |
| 0: vertical up |
| 1: horizontal left |
| 2: vertical down |
| 3: horizontal right |
| |
| A rectangle cycles up/right/down/left or up/left/down/right. |
| |
| The test fails if: |
| The path is closed, and followed by a line. |
| A second move creates a new endpoint. |
| A diagonal line is parsed. |
| There's more than four changes of direction. |
| There's a discontinuity on the line (e.g., a move in the middle) |
| The line reverses direction. |
| The path contains a quadratic or cubic. |
| The path contains fewer than four points. |
| *The rectangle doesn't complete a cycle. |
| *The final point isn't equal to the first point. |
| |
| *These last two conditions we relax if we have a 3-edge path that would |
| form a rectangle if it were closed (as we do when we fill a path) |
| |
| It's OK if the path has: |
| Several colinear line segments composing a rectangle side. |
| Single points on the rectangle side. |
| |
| The direction takes advantage of the corners found since opposite sides |
| must travel in opposite directions. |
| |
| FIXME: Allow colinear quads and cubics to be treated like lines. |
| FIXME: If the API passes fill-only, return true if the filled stroke |
| is a rectangle, though the caller failed to close the path. |
| |
| directions values: |
| 0x1 is set if the segment is horizontal |
| 0x2 is set if the segment is moving to the right or down |
| thus: |
| two directions are opposites iff (dirA ^ dirB) == 0x2 |
| two directions are perpendicular iff (dirA ^ dirB) == 0x1 |
| |
| */ |
| static int rect_make_dir(SkScalar dx, SkScalar dy) { |
| return ((0 != dx) << 0) | ((dx > 0 || dy > 0) << 1); |
| } |
| |
| bool SkPath::isRect(SkRect* rect, bool* isClosed, Direction* direction) const { |
| SkDEBUGCODE(this->validate();) |
| int currVerb = 0; |
| const SkPoint* pts = fPathRef->points(); |
| return SkPathPriv::IsRectContour(*this, false, &currVerb, &pts, isClosed, direction, rect); |
| } |
| |
| bool SkPath::isOval(SkRect* bounds) const { |
| return SkPathPriv::IsOval(*this, bounds, nullptr, nullptr); |
| } |
| |
| bool SkPath::isRRect(SkRRect* rrect) const { |
| return SkPathPriv::IsRRect(*this, rrect, nullptr, nullptr); |
| } |
| |
| int SkPath::countPoints() const { |
| return fPathRef->countPoints(); |
| } |
| |
| int SkPath::getPoints(SkPoint dst[], int max) const { |
| SkDEBUGCODE(this->validate();) |
| |
| SkASSERT(max >= 0); |
| SkASSERT(!max || dst); |
| int count = SkMin32(max, fPathRef->countPoints()); |
| sk_careful_memcpy(dst, fPathRef->points(), count * sizeof(SkPoint)); |
| return fPathRef->countPoints(); |
| } |
| |
| SkPoint SkPath::getPoint(int index) const { |
| if ((unsigned)index < (unsigned)fPathRef->countPoints()) { |
| return fPathRef->atPoint(index); |
| } |
| return SkPoint::Make(0, 0); |
| } |
| |
| int SkPath::countVerbs() const { |
| return fPathRef->countVerbs(); |
| } |
| |
| int SkPath::getVerbs(uint8_t dst[], int max) const { |
| SkDEBUGCODE(this->validate();) |
| |
| SkASSERT(max >= 0); |
| SkASSERT(!max || dst); |
| int count = SkMin32(max, fPathRef->countVerbs()); |
| if (count) { |
| memcpy(dst, fPathRef->verbsBegin(), count); |
| } |
| return fPathRef->countVerbs(); |
| } |
| |
| size_t SkPath::approximateBytesUsed() const { |
| size_t size = sizeof (SkPath); |
| if (fPathRef != nullptr) { |
| size += fPathRef->countPoints() * sizeof(SkPoint) |
| + fPathRef->countVerbs() |
| + fPathRef->countWeights() * sizeof(SkScalar); |
| } |
| |
| return size; |
| } |
| |
| bool SkPath::getLastPt(SkPoint* lastPt) const { |
| SkDEBUGCODE(this->validate();) |
| |
| int count = fPathRef->countPoints(); |
| if (count > 0) { |
| if (lastPt) { |
| *lastPt = fPathRef->atPoint(count - 1); |
| } |
| return true; |
| } |
| if (lastPt) { |
| lastPt->set(0, 0); |
| } |
| return false; |
| } |
| |
| void SkPath::setPt(int index, SkScalar x, SkScalar y) { |
| SkDEBUGCODE(this->validate();) |
| |
| int count = fPathRef->countPoints(); |
| if (count <= index) { |
| return; |
| } else { |
| SkPathRef::Editor ed(&fPathRef); |
| ed.atPoint(index)->set(x, y); |
| } |
| } |
| |
| void SkPath::setLastPt(SkScalar x, SkScalar y) { |
| SkDEBUGCODE(this->validate();) |
| |
| int count = fPathRef->countPoints(); |
| if (count == 0) { |
| this->moveTo(x, y); |
| } else { |
| SkPathRef::Editor ed(&fPathRef); |
| ed.atPoint(count-1)->set(x, y); |
| } |
| } |
| |
| // This is the public-facing non-const setConvexity(). |
| void SkPath::setConvexity(Convexity c) { |
| fConvexity.store(c, std::memory_order_relaxed); |
| } |
| |
| // Const hooks for working with fConvexity and fFirstDirection from const methods. |
| void SkPath::setConvexity(Convexity c) const { |
| fConvexity.store(c, std::memory_order_relaxed); |
| } |
| void SkPath::setFirstDirection(uint8_t d) const { |
| fFirstDirection.store(d, std::memory_order_relaxed); |
| } |
| uint8_t SkPath::getFirstDirection() const { |
| return fFirstDirection.load(std::memory_order_relaxed); |
| } |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| // Construction methods |
| |
| #define DIRTY_AFTER_EDIT \ |
| do { \ |
| this->setConvexity(kUnknown_Convexity); \ |
| this->setFirstDirection(SkPathPriv::kUnknown_FirstDirection); \ |
| } while (0) |
| |
| void SkPath::incReserve(int inc) { |
| SkDEBUGCODE(this->validate();) |
| if (inc > 0) { |
| SkPathRef::Editor(&fPathRef, inc, inc); |
| } |
| SkDEBUGCODE(this->validate();) |
| } |
| |
| SkPath& SkPath::moveTo(SkScalar x, SkScalar y) { |
| SkDEBUGCODE(this->validate();) |
| |
| SkPathRef::Editor ed(&fPathRef); |
| |
| // remember our index |
| fLastMoveToIndex = fPathRef->countPoints(); |
| |
| ed.growForVerb(kMove_Verb)->set(x, y); |
| |
| DIRTY_AFTER_EDIT; |
| return *this; |
| } |
| |
| SkPath& SkPath::rMoveTo(SkScalar x, SkScalar y) { |
| SkPoint pt; |
| this->getLastPt(&pt); |
| return this->moveTo(pt.fX + x, pt.fY + y); |
| } |
| |
| void SkPath::injectMoveToIfNeeded() { |
| if (fLastMoveToIndex < 0) { |
| SkScalar x, y; |
| if (fPathRef->countVerbs() == 0) { |
| x = y = 0; |
| } else { |
| const SkPoint& pt = fPathRef->atPoint(~fLastMoveToIndex); |
| x = pt.fX; |
| y = pt.fY; |
| } |
| this->moveTo(x, y); |
| } |
| } |
| |
| SkPath& SkPath::lineTo(SkScalar x, SkScalar y) { |
| SkDEBUGCODE(this->validate();) |
| |
| this->injectMoveToIfNeeded(); |
| |
| SkPathRef::Editor ed(&fPathRef); |
| ed.growForVerb(kLine_Verb)->set(x, y); |
| |
| DIRTY_AFTER_EDIT; |
| return *this; |
| } |
| |
| SkPath& SkPath::rLineTo(SkScalar x, SkScalar y) { |
| this->injectMoveToIfNeeded(); // This can change the result of this->getLastPt(). |
| SkPoint pt; |
| this->getLastPt(&pt); |
| return this->lineTo(pt.fX + x, pt.fY + y); |
| } |
| |
| SkPath& SkPath::quadTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2) { |
| SkDEBUGCODE(this->validate();) |
| |
| this->injectMoveToIfNeeded(); |
| |
| SkPathRef::Editor ed(&fPathRef); |
| SkPoint* pts = ed.growForVerb(kQuad_Verb); |
| pts[0].set(x1, y1); |
| pts[1].set(x2, y2); |
| |
| DIRTY_AFTER_EDIT; |
| return *this; |
| } |
| |
| SkPath& SkPath::rQuadTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2) { |
| this->injectMoveToIfNeeded(); // This can change the result of this->getLastPt(). |
| SkPoint pt; |
| this->getLastPt(&pt); |
| return this->quadTo(pt.fX + x1, pt.fY + y1, pt.fX + x2, pt.fY + y2); |
| } |
| |
| SkPath& SkPath::conicTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, |
| SkScalar w) { |
| // check for <= 0 or NaN with this test |
| if (!(w > 0)) { |
| this->lineTo(x2, y2); |
| } else if (!SkScalarIsFinite(w)) { |
| this->lineTo(x1, y1); |
| this->lineTo(x2, y2); |
| } else if (SK_Scalar1 == w) { |
| this->quadTo(x1, y1, x2, y2); |
| } else { |
| SkDEBUGCODE(this->validate();) |
| |
| this->injectMoveToIfNeeded(); |
| |
| SkPathRef::Editor ed(&fPathRef); |
| SkPoint* pts = ed.growForVerb(kConic_Verb, w); |
| pts[0].set(x1, y1); |
| pts[1].set(x2, y2); |
| |
| DIRTY_AFTER_EDIT; |
| } |
| return *this; |
| } |
| |
| SkPath& SkPath::rConicTo(SkScalar dx1, SkScalar dy1, SkScalar dx2, SkScalar dy2, |
| SkScalar w) { |
| this->injectMoveToIfNeeded(); // This can change the result of this->getLastPt(). |
| SkPoint pt; |
| this->getLastPt(&pt); |
| return this->conicTo(pt.fX + dx1, pt.fY + dy1, pt.fX + dx2, pt.fY + dy2, w); |
| } |
| |
| SkPath& SkPath::cubicTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, |
| SkScalar x3, SkScalar y3) { |
| SkDEBUGCODE(this->validate();) |
| |
| this->injectMoveToIfNeeded(); |
| |
| SkPathRef::Editor ed(&fPathRef); |
| SkPoint* pts = ed.growForVerb(kCubic_Verb); |
| pts[0].set(x1, y1); |
| pts[1].set(x2, y2); |
| pts[2].set(x3, y3); |
| |
| DIRTY_AFTER_EDIT; |
| return *this; |
| } |
| |
| SkPath& SkPath::rCubicTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, |
| SkScalar x3, SkScalar y3) { |
| this->injectMoveToIfNeeded(); // This can change the result of this->getLastPt(). |
| SkPoint pt; |
| this->getLastPt(&pt); |
| return this->cubicTo(pt.fX + x1, pt.fY + y1, pt.fX + x2, pt.fY + y2, |
| pt.fX + x3, pt.fY + y3); |
| } |
| |
| SkPath& SkPath::close() { |
| SkDEBUGCODE(this->validate();) |
| |
| int count = fPathRef->countVerbs(); |
| if (count > 0) { |
| switch (fPathRef->atVerb(count - 1)) { |
| case kLine_Verb: |
| case kQuad_Verb: |
| case kConic_Verb: |
| case kCubic_Verb: |
| case kMove_Verb: { |
| SkPathRef::Editor ed(&fPathRef); |
| ed.growForVerb(kClose_Verb); |
| break; |
| } |
| case kClose_Verb: |
| // don't add a close if it's the first verb or a repeat |
| break; |
| default: |
| SkDEBUGFAIL("unexpected verb"); |
| break; |
| } |
| } |
| |
| // signal that we need a moveTo to follow us (unless we're done) |
| #if 0 |
| if (fLastMoveToIndex >= 0) { |
| fLastMoveToIndex = ~fLastMoveToIndex; |
| } |
| #else |
| fLastMoveToIndex ^= ~fLastMoveToIndex >> (8 * sizeof(fLastMoveToIndex) - 1); |
| #endif |
| return *this; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| static void assert_known_direction(int dir) { |
| SkASSERT(SkPath::kCW_Direction == dir || SkPath::kCCW_Direction == dir); |
| } |
| |
| SkPath& SkPath::addRect(const SkRect& rect, Direction dir) { |
| return this->addRect(rect, dir, 0); |
| } |
| |
| SkPath& SkPath::addRect(SkScalar left, SkScalar top, SkScalar right, |
| SkScalar bottom, Direction dir) { |
| return this->addRect(SkRect::MakeLTRB(left, top, right, bottom), dir, 0); |
| } |
| |
| SkPath& SkPath::addRect(const SkRect &rect, Direction dir, unsigned startIndex) { |
| assert_known_direction(dir); |
| this->setFirstDirection(this->hasOnlyMoveTos() ? (SkPathPriv::FirstDirection)dir |
| : SkPathPriv::kUnknown_FirstDirection); |
| SkAutoDisableDirectionCheck addc(this); |
| SkAutoPathBoundsUpdate apbu(this, rect); |
| |
| SkDEBUGCODE(int initialVerbCount = this->countVerbs()); |
| |
| const int kVerbs = 5; // moveTo + 3x lineTo + close |
| this->incReserve(kVerbs); |
| |
| SkPath_RectPointIterator iter(rect, dir, startIndex); |
| |
| this->moveTo(iter.current()); |
| this->lineTo(iter.next()); |
| this->lineTo(iter.next()); |
| this->lineTo(iter.next()); |
| this->close(); |
| |
| SkASSERT(this->countVerbs() == initialVerbCount + kVerbs); |
| return *this; |
| } |
| |
| SkPath& SkPath::addPoly(const SkPoint pts[], int count, bool close) { |
| SkDEBUGCODE(this->validate();) |
| if (count <= 0) { |
| return *this; |
| } |
| |
| fLastMoveToIndex = fPathRef->countPoints(); |
| |
| // +close makes room for the extra kClose_Verb |
| SkPathRef::Editor ed(&fPathRef, count+close, count); |
| |
| ed.growForVerb(kMove_Verb)->set(pts[0].fX, pts[0].fY); |
| if (count > 1) { |
| SkPoint* p = ed.growForRepeatedVerb(kLine_Verb, count - 1); |
| memcpy(p, &pts[1], (count-1) * sizeof(SkPoint)); |
| } |
| |
| if (close) { |
| ed.growForVerb(kClose_Verb); |
| fLastMoveToIndex ^= ~fLastMoveToIndex >> (8 * sizeof(fLastMoveToIndex) - 1); |
| } |
| |
| DIRTY_AFTER_EDIT; |
| SkDEBUGCODE(this->validate();) |
| return *this; |
| } |
| |
| #include "src/core/SkGeometry.h" |
| |
| static bool arc_is_lone_point(const SkRect& oval, SkScalar startAngle, SkScalar sweepAngle, |
| SkPoint* pt) { |
| if (0 == sweepAngle && (0 == startAngle || SkIntToScalar(360) == startAngle)) { |
| // Chrome uses this path to move into and out of ovals. If not |
| // treated as a special case the moves can distort the oval's |
| // bounding box (and break the circle special case). |
| pt->set(oval.fRight, oval.centerY()); |
| return true; |
| } else if (0 == oval.width() && 0 == oval.height()) { |
| // Chrome will sometimes create 0 radius round rects. Having degenerate |
| // quad segments in the path prevents the path from being recognized as |
| // a rect. |
| // TODO: optimizing the case where only one of width or height is zero |
| // should also be considered. This case, however, doesn't seem to be |
| // as common as the single point case. |
| pt->set(oval.fRight, oval.fTop); |
| return true; |
| } |
| return false; |
| } |
| |
| // Return the unit vectors pointing at the start/stop points for the given start/sweep angles |
| // |
| static void angles_to_unit_vectors(SkScalar startAngle, SkScalar sweepAngle, |
| SkVector* startV, SkVector* stopV, SkRotationDirection* dir) { |
| SkScalar startRad = SkDegreesToRadians(startAngle), |
| stopRad = SkDegreesToRadians(startAngle + sweepAngle); |
| |
| startV->fY = SkScalarSinSnapToZero(startRad); |
| startV->fX = SkScalarCosSnapToZero(startRad); |
| stopV->fY = SkScalarSinSnapToZero(stopRad); |
| stopV->fX = SkScalarCosSnapToZero(stopRad); |
| |
| /* If the sweep angle is nearly (but less than) 360, then due to precision |
| loss in radians-conversion and/or sin/cos, we may end up with coincident |
| vectors, which will fool SkBuildQuadArc into doing nothing (bad) instead |
| of drawing a nearly complete circle (good). |
| e.g. canvas.drawArc(0, 359.99, ...) |
| -vs- canvas.drawArc(0, 359.9, ...) |
| We try to detect this edge case, and tweak the stop vector |
| */ |
| if (*startV == *stopV) { |
| SkScalar sw = SkScalarAbs(sweepAngle); |
| if (sw < SkIntToScalar(360) && sw > SkIntToScalar(359)) { |
| // make a guess at a tiny angle (in radians) to tweak by |
| SkScalar deltaRad = SkScalarCopySign(SK_Scalar1/512, sweepAngle); |
| // not sure how much will be enough, so we use a loop |
| do { |
| stopRad -= deltaRad; |
| stopV->fY = SkScalarSinSnapToZero(stopRad); |
| stopV->fX = SkScalarCosSnapToZero(stopRad); |
| } while (*startV == *stopV); |
| } |
| } |
| *dir = sweepAngle > 0 ? kCW_SkRotationDirection : kCCW_SkRotationDirection; |
| } |
| |
| /** |
| * If this returns 0, then the caller should just line-to the singlePt, else it should |
| * ignore singlePt and append the specified number of conics. |
| */ |
| static int build_arc_conics(const SkRect& oval, const SkVector& start, const SkVector& stop, |
| SkRotationDirection dir, SkConic conics[SkConic::kMaxConicsForArc], |
| SkPoint* singlePt) { |
| SkMatrix matrix; |
| |
| matrix.setScale(SkScalarHalf(oval.width()), SkScalarHalf(oval.height())); |
| matrix.postTranslate(oval.centerX(), oval.centerY()); |
| |
| int count = SkConic::BuildUnitArc(start, stop, dir, &matrix, conics); |
| if (0 == count) { |
| matrix.mapXY(stop.x(), stop.y(), singlePt); |
| } |
| return count; |
| } |
| |
| SkPath& SkPath::addRoundRect(const SkRect& rect, const SkScalar radii[], |
| Direction dir) { |
| SkRRect rrect; |
| rrect.setRectRadii(rect, (const SkVector*) radii); |
| return this->addRRect(rrect, dir); |
| } |
| |
| SkPath& SkPath::addRRect(const SkRRect& rrect, Direction dir) { |
| // legacy start indices: 6 (CW) and 7(CCW) |
| return this->addRRect(rrect, dir, dir == kCW_Direction ? 6 : 7); |
| } |
| |
| SkPath& SkPath::addRRect(const SkRRect &rrect, Direction dir, unsigned startIndex) { |
| assert_known_direction(dir); |
| |
| bool isRRect = hasOnlyMoveTos(); |
| const SkRect& bounds = rrect.getBounds(); |
| |
| if (rrect.isRect() || rrect.isEmpty()) { |
| // degenerate(rect) => radii points are collapsing |
| this->addRect(bounds, dir, (startIndex + 1) / 2); |
| } else if (rrect.isOval()) { |
| // degenerate(oval) => line points are collapsing |
| this->addOval(bounds, dir, startIndex / 2); |
| } else { |
| this->setFirstDirection(this->hasOnlyMoveTos() ? (SkPathPriv::FirstDirection)dir |
| : SkPathPriv::kUnknown_FirstDirection); |
| |
| SkAutoPathBoundsUpdate apbu(this, bounds); |
| SkAutoDisableDirectionCheck addc(this); |
| |
| // we start with a conic on odd indices when moving CW vs. even indices when moving CCW |
| const bool startsWithConic = ((startIndex & 1) == (dir == kCW_Direction)); |
| const SkScalar weight = SK_ScalarRoot2Over2; |
| |
| SkDEBUGCODE(int initialVerbCount = this->countVerbs()); |
| const int kVerbs = startsWithConic |
| ? 9 // moveTo + 4x conicTo + 3x lineTo + close |
| : 10; // moveTo + 4x lineTo + 4x conicTo + close |
| this->incReserve(kVerbs); |
| |
| SkPath_RRectPointIterator rrectIter(rrect, dir, startIndex); |
| // Corner iterator indices follow the collapsed radii model, |
| // adjusted such that the start pt is "behind" the radii start pt. |
| const unsigned rectStartIndex = startIndex / 2 + (dir == kCW_Direction ? 0 : 1); |
| SkPath_RectPointIterator rectIter(bounds, dir, rectStartIndex); |
| |
| this->moveTo(rrectIter.current()); |
| if (startsWithConic) { |
| for (unsigned i = 0; i < 3; ++i) { |
| this->conicTo(rectIter.next(), rrectIter.next(), weight); |
| this->lineTo(rrectIter.next()); |
| } |
| this->conicTo(rectIter.next(), rrectIter.next(), weight); |
| // final lineTo handled by close(). |
| } else { |
| for (unsigned i = 0; i < 4; ++i) { |
| this->lineTo(rrectIter.next()); |
| this->conicTo(rectIter.next(), rrectIter.next(), weight); |
| } |
| } |
| this->close(); |
| |
| SkPathRef::Editor ed(&fPathRef); |
| ed.setIsRRect(isRRect, dir, startIndex % 8); |
| |
| SkASSERT(this->countVerbs() == initialVerbCount + kVerbs); |
| } |
| |
| SkDEBUGCODE(fPathRef->validate();) |
| return *this; |
| } |
| |
| bool SkPath::hasOnlyMoveTos() const { |
| int count = fPathRef->countVerbs(); |
| const uint8_t* verbs = fPathRef->verbsBegin(); |
| for (int i = 0; i < count; ++i) { |
| if (*verbs == kLine_Verb || |
| *verbs == kQuad_Verb || |
| *verbs == kConic_Verb || |
| *verbs == kCubic_Verb) { |
| return false; |
| } |
| ++verbs; |
| } |
| return true; |
| } |
| |
| bool SkPath::isZeroLengthSincePoint(int startPtIndex) const { |
| int count = fPathRef->countPoints() - startPtIndex; |
| if (count < 2) { |
| return true; |
| } |
| const SkPoint* pts = fPathRef.get()->points() + startPtIndex; |
| const SkPoint& first = *pts; |
| for (int index = 1; index < count; ++index) { |
| if (first != pts[index]) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| SkPath& SkPath::addRoundRect(const SkRect& rect, SkScalar rx, SkScalar ry, |
| Direction dir) { |
| assert_known_direction(dir); |
| |
| if (rx < 0 || ry < 0) { |
| return *this; |
| } |
| |
| SkRRect rrect; |
| rrect.setRectXY(rect, rx, ry); |
| return this->addRRect(rrect, dir); |
| } |
| |
| SkPath& SkPath::addOval(const SkRect& oval, Direction dir) { |
| // legacy start index: 1 |
| return this->addOval(oval, dir, 1); |
| } |
| |
| SkPath& SkPath::addOval(const SkRect &oval, Direction dir, unsigned startPointIndex) { |
| assert_known_direction(dir); |
| |
| /* If addOval() is called after previous moveTo(), |
| this path is still marked as an oval. This is used to |
| fit into WebKit's calling sequences. |
| We can't simply check isEmpty() in this case, as additional |
| moveTo() would mark the path non empty. |
| */ |
| bool isOval = hasOnlyMoveTos(); |
| if (isOval) { |
| this->setFirstDirection((SkPathPriv::FirstDirection)dir); |
| } else { |
| this->setFirstDirection(SkPathPriv::kUnknown_FirstDirection); |
| } |
| |
| SkAutoDisableDirectionCheck addc(this); |
| SkAutoPathBoundsUpdate apbu(this, oval); |
| |
| SkDEBUGCODE(int initialVerbCount = this->countVerbs()); |
| const int kVerbs = 6; // moveTo + 4x conicTo + close |
| this->incReserve(kVerbs); |
| |
| SkPath_OvalPointIterator ovalIter(oval, dir, startPointIndex); |
| // The corner iterator pts are tracking "behind" the oval/radii pts. |
| SkPath_RectPointIterator rectIter(oval, dir, startPointIndex + (dir == kCW_Direction ? 0 : 1)); |
| const SkScalar weight = SK_ScalarRoot2Over2; |
| |
| this->moveTo(ovalIter.current()); |
| for (unsigned i = 0; i < 4; ++i) { |
| this->conicTo(rectIter.next(), ovalIter.next(), weight); |
| } |
| this->close(); |
| |
| SkASSERT(this->countVerbs() == initialVerbCount + kVerbs); |
| |
| SkPathRef::Editor ed(&fPathRef); |
| |
| ed.setIsOval(isOval, kCCW_Direction == dir, startPointIndex % 4); |
| return *this; |
| } |
| |
| SkPath& SkPath::addCircle(SkScalar x, SkScalar y, SkScalar r, Direction dir) { |
| if (r > 0) { |
| this->addOval(SkRect::MakeLTRB(x - r, y - r, x + r, y + r), dir); |
| } |
| return *this; |
| } |
| |
| SkPath& SkPath::arcTo(const SkRect& oval, SkScalar startAngle, SkScalar sweepAngle, |
| bool forceMoveTo) { |
| if (oval.width() < 0 || oval.height() < 0) { |
| return *this; |
| } |
| |
| if (fPathRef->countVerbs() == 0) { |
| forceMoveTo = true; |
| } |
| |
| SkPoint lonePt; |
| if (arc_is_lone_point(oval, startAngle, sweepAngle, &lonePt)) { |
| return forceMoveTo ? this->moveTo(lonePt) : this->lineTo(lonePt); |
| } |
| |
| SkVector startV, stopV; |
| SkRotationDirection dir; |
| angles_to_unit_vectors(startAngle, sweepAngle, &startV, &stopV, &dir); |
| |
| SkPoint singlePt; |
| |
| // Adds a move-to to 'pt' if forceMoveTo is true. Otherwise a lineTo unless we're sufficiently |
| // close to 'pt' currently. This prevents spurious lineTos when adding a series of contiguous |
| // arcs from the same oval. |
| auto addPt = [&forceMoveTo, this](const SkPoint& pt) { |
| SkPoint lastPt; |
| if (forceMoveTo) { |
| this->moveTo(pt); |
| } else if (!this->getLastPt(&lastPt) || |
| !SkScalarNearlyEqual(lastPt.fX, pt.fX) || |
| !SkScalarNearlyEqual(lastPt.fY, pt.fY)) { |
| this->lineTo(pt); |
| } |
| }; |
| |
| // At this point, we know that the arc is not a lone point, but startV == stopV |
| // indicates that the sweepAngle is too small such that angles_to_unit_vectors |
| // cannot handle it. |
| if (startV == stopV) { |
| SkScalar endAngle = SkDegreesToRadians(startAngle + sweepAngle); |
| SkScalar radiusX = oval.width() / 2; |
| SkScalar radiusY = oval.height() / 2; |
| // We do not use SkScalar[Sin|Cos]SnapToZero here. When sin(startAngle) is 0 and sweepAngle |
| // is very small and radius is huge, the expected behavior here is to draw a line. But |
| // calling SkScalarSinSnapToZero will make sin(endAngle) be 0 which will then draw a dot. |
| singlePt.set(oval.centerX() + radiusX * SkScalarCos(endAngle), |
| oval.centerY() + radiusY * SkScalarSin(endAngle)); |
| addPt(singlePt); |
| return *this; |
| } |
| |
| SkConic conics[SkConic::kMaxConicsForArc]; |
| int count = build_arc_conics(oval, startV, stopV, dir, conics, &singlePt); |
| if (count) { |
| this->incReserve(count * 2 + 1); |
| const SkPoint& pt = conics[0].fPts[0]; |
| addPt(pt); |
| for (int i = 0; i < count; ++i) { |
| this->conicTo(conics[i].fPts[1], conics[i].fPts[2], conics[i].fW); |
| } |
| } else { |
| addPt(singlePt); |
| } |
| return *this; |
| } |
| |
| // This converts the SVG arc to conics. |
| // Partly adapted from Niko's code in kdelibs/kdecore/svgicons. |
| // Then transcribed from webkit/chrome's SVGPathNormalizer::decomposeArcToCubic() |
| // See also SVG implementation notes: |
| // http://www.w3.org/TR/SVG/implnote.html#ArcConversionEndpointToCenter |
| // Note that arcSweep bool value is flipped from the original implementation. |
| SkPath& SkPath::arcTo(SkScalar rx, SkScalar ry, SkScalar angle, SkPath::ArcSize arcLarge, |
| SkPath::Direction arcSweep, SkScalar x, SkScalar y) { |
| this->injectMoveToIfNeeded(); |
| SkPoint srcPts[2]; |
| this->getLastPt(&srcPts[0]); |
| // If rx = 0 or ry = 0 then this arc is treated as a straight line segment (a "lineto") |
| // joining the endpoints. |
| // http://www.w3.org/TR/SVG/implnote.html#ArcOutOfRangeParameters |
| if (!rx || !ry) { |
| return this->lineTo(x, y); |
| } |
| // If the current point and target point for the arc are identical, it should be treated as a |
| // zero length path. This ensures continuity in animations. |
| srcPts[1].set(x, y); |
| if (srcPts[0] == srcPts[1]) { |
| return this->lineTo(x, y); |
| } |
| rx = SkScalarAbs(rx); |
| ry = SkScalarAbs(ry); |
| SkVector midPointDistance = srcPts[0] - srcPts[1]; |
| midPointDistance *= 0.5f; |
| |
| SkMatrix pointTransform; |
| pointTransform.setRotate(-angle); |
| |
| SkPoint transformedMidPoint; |
| pointTransform.mapPoints(&transformedMidPoint, &midPointDistance, 1); |
| SkScalar squareRx = rx * rx; |
| SkScalar squareRy = ry * ry; |
| SkScalar squareX = transformedMidPoint.fX * transformedMidPoint.fX; |
| SkScalar squareY = transformedMidPoint.fY * transformedMidPoint.fY; |
| |
| // Check if the radii are big enough to draw the arc, scale radii if not. |
| // http://www.w3.org/TR/SVG/implnote.html#ArcCorrectionOutOfRangeRadii |
| SkScalar radiiScale = squareX / squareRx + squareY / squareRy; |
| if (radiiScale > 1) { |
| radiiScale = SkScalarSqrt(radiiScale); |
| rx *= radiiScale; |
| ry *= radiiScale; |
| } |
| |
| pointTransform.setScale(1 / rx, 1 / ry); |
| pointTransform.preRotate(-angle); |
| |
| SkPoint unitPts[2]; |
| pointTransform.mapPoints(unitPts, srcPts, (int) SK_ARRAY_COUNT(unitPts)); |
| SkVector delta = unitPts[1] - unitPts[0]; |
| |
| SkScalar d = delta.fX * delta.fX + delta.fY * delta.fY; |
| SkScalar scaleFactorSquared = SkTMax(1 / d - 0.25f, 0.f); |
| |
| SkScalar scaleFactor = SkScalarSqrt(scaleFactorSquared); |
| if (SkToBool(arcSweep) != SkToBool(arcLarge)) { // flipped from the original implementation |
| scaleFactor = -scaleFactor; |
| } |
| delta.scale(scaleFactor); |
| SkPoint centerPoint = unitPts[0] + unitPts[1]; |
| centerPoint *= 0.5f; |
| centerPoint.offset(-delta.fY, delta.fX); |
| unitPts[0] -= centerPoint; |
| unitPts[1] -= centerPoint; |
| SkScalar theta1 = SkScalarATan2(unitPts[0].fY, unitPts[0].fX); |
| SkScalar theta2 = SkScalarATan2(unitPts[1].fY, unitPts[1].fX); |
| SkScalar thetaArc = theta2 - theta1; |
| if (thetaArc < 0 && !arcSweep) { // arcSweep flipped from the original implementation |
| thetaArc += SK_ScalarPI * 2; |
| } else if (thetaArc > 0 && arcSweep) { // arcSweep flipped from the original implementation |
| thetaArc -= SK_ScalarPI * 2; |
| } |
| |
| // Very tiny angles cause our subsequent math to go wonky (skbug.com/9272) |
| // so we do a quick check here. The precise tolerance amount is just made up. |
| // PI/million happens to fix the bug in 9272, but a larger value is probably |
| // ok too. |
| if (SkScalarAbs(thetaArc) < (SK_ScalarPI / (1000 * 1000))) { |
| return this->lineTo(x, y); |
| } |
| |
| pointTransform.setRotate(angle); |
| pointTransform.preScale(rx, ry); |
| |
| // the arc may be slightly bigger than 1/4 circle, so allow up to 1/3rd |
| int segments = SkScalarCeilToInt(SkScalarAbs(thetaArc / (2 * SK_ScalarPI / 3))); |
| SkScalar thetaWidth = thetaArc / segments; |
| SkScalar t = SkScalarTan(0.5f * thetaWidth); |
| if (!SkScalarIsFinite(t)) { |
| return *this; |
| } |
| SkScalar startTheta = theta1; |
| SkScalar w = SkScalarSqrt(SK_ScalarHalf + SkScalarCos(thetaWidth) * SK_ScalarHalf); |
| auto scalar_is_integer = [](SkScalar scalar) -> bool { |
| return scalar == SkScalarFloorToScalar(scalar); |
| }; |
| bool expectIntegers = SkScalarNearlyZero(SK_ScalarPI/2 - SkScalarAbs(thetaWidth)) && |
| scalar_is_integer(rx) && scalar_is_integer(ry) && |
| scalar_is_integer(x) && scalar_is_integer(y); |
| |
| for (int i = 0; i < segments; ++i) { |
| SkScalar endTheta = startTheta + thetaWidth, |
| sinEndTheta = SkScalarSinSnapToZero(endTheta), |
| cosEndTheta = SkScalarCosSnapToZero(endTheta); |
| |
| unitPts[1].set(cosEndTheta, sinEndTheta); |
| unitPts[1] += centerPoint; |
| unitPts[0] = unitPts[1]; |
| unitPts[0].offset(t * sinEndTheta, -t * cosEndTheta); |
| SkPoint mapped[2]; |
| pointTransform.mapPoints(mapped, unitPts, (int) SK_ARRAY_COUNT(unitPts)); |
| /* |
| Computing the arc width introduces rounding errors that cause arcs to start |
| outside their marks. A round rect may lose convexity as a result. If the input |
| values are on integers, place the conic on integers as well. |
| */ |
| if (expectIntegers) { |
| for (SkPoint& point : mapped) { |
| point.fX = SkScalarRoundToScalar(point.fX); |
| point.fY = SkScalarRoundToScalar(point.fY); |
| } |
| } |
| this->conicTo(mapped[0], mapped[1], w); |
| startTheta = endTheta; |
| } |
| return *this; |
| } |
| |
| SkPath& SkPath::rArcTo(SkScalar rx, SkScalar ry, SkScalar xAxisRotate, SkPath::ArcSize largeArc, |
| SkPath::Direction sweep, SkScalar dx, SkScalar dy) { |
| SkPoint currentPoint; |
| this->getLastPt(¤tPoint); |
| return this->arcTo(rx, ry, xAxisRotate, largeArc, sweep, |
| currentPoint.fX + dx, currentPoint.fY + dy); |
| } |
| |
| SkPath& SkPath::addArc(const SkRect& oval, SkScalar startAngle, SkScalar sweepAngle) { |
| if (oval.isEmpty() || 0 == sweepAngle) { |
| return *this; |
| } |
| |
| const SkScalar kFullCircleAngle = SkIntToScalar(360); |
| |
| if (sweepAngle >= kFullCircleAngle || sweepAngle <= -kFullCircleAngle) { |
| // We can treat the arc as an oval if it begins at one of our legal starting positions. |
| // See SkPath::addOval() docs. |
| SkScalar startOver90 = startAngle / 90.f; |
| SkScalar startOver90I = SkScalarRoundToScalar(startOver90); |
| SkScalar error = startOver90 - startOver90I; |
| if (SkScalarNearlyEqual(error, 0)) { |
| // Index 1 is at startAngle == 0. |
| SkScalar startIndex = std::fmod(startOver90I + 1.f, 4.f); |
| startIndex = startIndex < 0 ? startIndex + 4.f : startIndex; |
| return this->addOval(oval, sweepAngle > 0 ? kCW_Direction : kCCW_Direction, |
| (unsigned) startIndex); |
| } |
| } |
| return this->arcTo(oval, startAngle, sweepAngle, true); |
| } |
| |
| /* |
| Need to handle the case when the angle is sharp, and our computed end-points |
| for the arc go behind pt1 and/or p2... |
| */ |
| SkPath& SkPath::arcTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, SkScalar radius) { |
| if (radius == 0) { |
| return this->lineTo(x1, y1); |
| } |
| |
| // need to know our prev pt so we can construct tangent vectors |
| SkPoint start; |
| this->getLastPt(&start); |
| |
| // need double precision for these calcs. |
| SkDVector befored, afterd; |
| befored.set({x1 - start.fX, y1 - start.fY}).normalize(); |
| afterd.set({x2 - x1, y2 - y1}).normalize(); |
| double cosh = befored.dot(afterd); |
| double sinh = befored.cross(afterd); |
| |
| if (!befored.isFinite() || !afterd.isFinite() || SkScalarNearlyZero(SkDoubleToScalar(sinh))) { |
| return this->lineTo(x1, y1); |
| } |
| |
| // safe to convert back to floats now |
| SkVector before = befored.asSkVector(); |
| SkVector after = afterd.asSkVector(); |
| SkScalar dist = SkScalarAbs(SkDoubleToScalar(radius * (1 - cosh) / sinh)); |
| SkScalar xx = x1 - dist * before.fX; |
| SkScalar yy = y1 - dist * before.fY; |
| after.setLength(dist); |
| this->lineTo(xx, yy); |
| SkScalar weight = SkScalarSqrt(SkDoubleToScalar(SK_ScalarHalf + cosh * 0.5)); |
| return this->conicTo(x1, y1, x1 + after.fX, y1 + after.fY, weight); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| SkPath& SkPath::addPath(const SkPath& path, SkScalar dx, SkScalar dy, AddPathMode mode) { |
| SkMatrix matrix; |
| |
| matrix.setTranslate(dx, dy); |
| return this->addPath(path, matrix, mode); |
| } |
| |
| SkPath& SkPath::addPath(const SkPath& srcPath, const SkMatrix& matrix, AddPathMode mode) { |
| // Detect if we're trying to add ourself |
| const SkPath* src = &srcPath; |
| SkTLazy<SkPath> tmp; |
| if (this == src) { |
| src = tmp.set(srcPath); |
| } |
| |
| SkPathRef::Editor(&fPathRef, src->countVerbs(), src->countPoints()); |
| |
| RawIter iter(*src); |
| SkPoint pts[4]; |
| Verb verb; |
| |
| SkMatrixPriv::MapPtsProc proc = SkMatrixPriv::GetMapPtsProc(matrix); |
| bool firstVerb = true; |
| while ((verb = iter.next(pts)) != kDone_Verb) { |
| switch (verb) { |
| case kMove_Verb: |
| proc(matrix, &pts[0], &pts[0], 1); |
| if (firstVerb && mode == kExtend_AddPathMode && !isEmpty()) { |
| injectMoveToIfNeeded(); // In case last contour is closed |
| SkPoint lastPt; |
| // don't add lineTo if it is degenerate |
| if (fLastMoveToIndex < 0 || !this->getLastPt(&lastPt) || lastPt != pts[0]) { |
| this->lineTo(pts[0]); |
| } |
| } else { |
| this->moveTo(pts[0]); |
| } |
| break; |
| case kLine_Verb: |
| proc(matrix, &pts[1], &pts[1], 1); |
| this->lineTo(pts[1]); |
| break; |
| case kQuad_Verb: |
| proc(matrix, &pts[1], &pts[1], 2); |
| this->quadTo(pts[1], pts[2]); |
| break; |
| case kConic_Verb: |
| proc(matrix, &pts[1], &pts[1], 2); |
| this->conicTo(pts[1], pts[2], iter.conicWeight()); |
| break; |
| case kCubic_Verb: |
| proc(matrix, &pts[1], &pts[1], 3); |
| this->cubicTo(pts[1], pts[2], pts[3]); |
| break; |
| case kClose_Verb: |
| this->close(); |
| break; |
| default: |
| SkDEBUGFAIL("unknown verb"); |
| } |
| firstVerb = false; |
| } |
| return *this; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| static int pts_in_verb(unsigned verb) { |
| static const uint8_t gPtsInVerb[] = { |
| 1, // kMove |
| 1, // kLine |
| 2, // kQuad |
| 2, // kConic |
| 3, // kCubic |
| 0, // kClose |
| 0 // kDone |
| }; |
| |
| SkASSERT(verb < SK_ARRAY_COUNT(gPtsInVerb)); |
| return gPtsInVerb[verb]; |
| } |
| |
| // ignore the last point of the 1st contour |
| SkPath& SkPath::reversePathTo(const SkPath& path) { |
| if (path.fPathRef->fVerbs.count() == 0) { |
| return *this; |
| } |
| |
| const uint8_t* verbs = path.fPathRef->verbsEnd(); |
| const uint8_t* verbsBegin = path.fPathRef->verbsBegin(); |
| SkASSERT(verbsBegin[0] == kMove_Verb); |
| const SkPoint* pts = path.fPathRef->pointsEnd() - 1; |
| const SkScalar* conicWeights = path.fPathRef->conicWeightsEnd(); |
| |
| while (verbs > verbsBegin) { |
| uint8_t v = *--verbs; |
| pts -= pts_in_verb(v); |
| switch (v) { |
| case kMove_Verb: |
| // if the path has multiple contours, stop after reversing the last |
| return *this; |
| case kLine_Verb: |
| this->lineTo(pts[0]); |
| break; |
| case kQuad_Verb: |
| this->quadTo(pts[1], pts[0]); |
| break; |
| case kConic_Verb: |
| this->conicTo(pts[1], pts[0], *--conicWeights); |
| break; |
| case kCubic_Verb: |
| this->cubicTo(pts[2], pts[1], pts[0]); |
| break; |
| case kClose_Verb: |
| break; |
| default: |
| SkDEBUGFAIL("bad verb"); |
| break; |
| } |
| } |
| return *this; |
| } |
| |
| SkPath& SkPath::reverseAddPath(const SkPath& srcPath) { |
| // Detect if we're trying to add ourself |
| const SkPath* src = &srcPath; |
| SkTLazy<SkPath> tmp; |
| if (this == src) { |
| src = tmp.set(srcPath); |
| } |
| |
| SkPathRef::Editor ed(&fPathRef, src->countVerbs(), src->countPoints()); |
| |
| const uint8_t* verbsBegin = src->fPathRef->verbsBegin(); |
| const uint8_t* verbs = src->fPathRef->verbsEnd(); |
| const SkPoint* pts = src->fPathRef->pointsEnd(); |
| const SkScalar* conicWeights = src->fPathRef->conicWeightsEnd(); |
| |
| bool needMove = true; |
| bool needClose = false; |
| while (verbs > verbsBegin) { |
| uint8_t v = *--verbs; |
| int n = pts_in_verb(v); |
| |
| if (needMove) { |
| --pts; |
| this->moveTo(pts->fX, pts->fY); |
| needMove = false; |
| } |
| pts -= n; |
| switch (v) { |
| case kMove_Verb: |
| if (needClose) { |
| this->close(); |
| needClose = false; |
| } |
| needMove = true; |
| pts += 1; // so we see the point in "if (needMove)" above |
| break; |
| case kLine_Verb: |
| this->lineTo(pts[0]); |
| break; |
| case kQuad_Verb: |
| this->quadTo(pts[1], pts[0]); |
| break; |
| case kConic_Verb: |
| this->conicTo(pts[1], pts[0], *--conicWeights); |
| break; |
| case kCubic_Verb: |
| this->cubicTo(pts[2], pts[1], pts[0]); |
| break; |
| case kClose_Verb: |
| needClose = true; |
| break; |
| default: |
| SkDEBUGFAIL("unexpected verb"); |
| } |
| } |
| return *this; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| void SkPath::offset(SkScalar dx, SkScalar dy, SkPath* dst) const { |
| SkMatrix matrix; |
| |
| matrix.setTranslate(dx, dy); |
| this->transform(matrix, dst); |
| } |
| |
| static void subdivide_cubic_to(SkPath* path, const SkPoint pts[4], |
| int level = 2) { |
| if (--level >= 0) { |
| SkPoint tmp[7]; |
| |
| SkChopCubicAtHalf(pts, tmp); |
| subdivide_cubic_to(path, &tmp[0], level); |
| subdivide_cubic_to(path, &tmp[3], level); |
| } else { |
| path->cubicTo(pts[1], pts[2], pts[3]); |
| } |
| } |
| |
| void SkPath::transform(const SkMatrix& matrix, SkPath* dst) const { |
| if (matrix.isIdentity()) { |
| if (dst != nullptr && dst != this) { |
| *dst = *this; |
| } |
| return; |
| } |
| |
| SkDEBUGCODE(this->validate();) |
| if (dst == nullptr) { |
| dst = (SkPath*)this; |
| } |
| |
| if (matrix.hasPerspective()) { |
| SkPath tmp; |
| tmp.fFillType = fFillType; |
| |
| SkPath::Iter iter(*this, false); |
| SkPoint pts[4]; |
| SkPath::Verb verb; |
| |
| while ((verb = iter.next(pts)) != kDone_Verb) { |
| switch (verb) { |
| case kMove_Verb: |
| tmp.moveTo(pts[0]); |
| break; |
| case kLine_Verb: |
| tmp.lineTo(pts[1]); |
| break; |
| case kQuad_Verb: |
| // promote the quad to a conic |
| tmp.conicTo(pts[1], pts[2], |
| SkConic::TransformW(pts, SK_Scalar1, matrix)); |
| break; |
| case kConic_Verb: |
| tmp.conicTo(pts[1], pts[2], |
| SkConic::TransformW(pts, iter.conicWeight(), matrix)); |
| break; |
| case kCubic_Verb: |
| subdivide_cubic_to(&tmp, pts); |
| break; |
| case kClose_Verb: |
| tmp.close(); |
| break; |
| default: |
| SkDEBUGFAIL("unknown verb"); |
| break; |
| } |
| } |
| |
| dst->swap(tmp); |
| SkPathRef::Editor ed(&dst->fPathRef); |
| matrix.mapPoints(ed.writablePoints(), ed.pathRef()->countPoints()); |
| dst->setFirstDirection(SkPathPriv::kUnknown_FirstDirection); |
| } else { |
| Convexity convexity = this->getConvexityOrUnknown(); |
| |
| SkPathRef::CreateTransformedCopy(&dst->fPathRef, *fPathRef.get(), matrix); |
| |
| if (this != dst) { |
| dst->fLastMoveToIndex = fLastMoveToIndex; |
| dst->fFillType = fFillType; |
| dst->fIsVolatile = fIsVolatile; |
| } |
| |
| // Due to finite/fragile float numerics, we can't assume that a convex path remains |
| // convex after a transformation, so mark it as unknown here. |
| // However, some transformations are thought to be safe: |
| // axis-aligned values under scale/translate. |
| // |
| // See skbug.com/8606 |
| // If we can land a robust convex scan-converter, we may be able to relax/remove this |
| // check, and keep convex paths marked as such after a general transform... |
| // |
| if (matrix.isScaleTranslate() && SkPathPriv::IsAxisAligned(*this)) { |
| dst->setConvexity(convexity); |
| } else { |
| dst->setConvexity(kUnknown_Convexity); |
| } |
| |
| if (this->getFirstDirection() == SkPathPriv::kUnknown_FirstDirection) { |
| dst->setFirstDirection(SkPathPriv::kUnknown_FirstDirection); |
| } else { |
| SkScalar det2x2 = |
| matrix.get(SkMatrix::kMScaleX) * matrix.get(SkMatrix::kMScaleY) - |
| matrix.get(SkMatrix::kMSkewX) * matrix.get(SkMatrix::kMSkewY); |
| if (det2x2 < 0) { |
| dst->setFirstDirection( |
| SkPathPriv::OppositeFirstDirection( |
| (SkPathPriv::FirstDirection)this->getFirstDirection())); |
| } else if (det2x2 > 0) { |
| dst->setFirstDirection(this->getFirstDirection()); |
| } else { |
| dst->setFirstDirection(SkPathPriv::kUnknown_FirstDirection); |
| } |
| } |
| |
| SkDEBUGCODE(dst->validate();) |
| } |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| SkPath::Iter::Iter() { |
| #ifdef SK_DEBUG |
| fPts = nullptr; |
| fConicWeights = nullptr; |
| fMoveTo.fX = fMoveTo.fY = fLastPt.fX = fLastPt.fY = 0; |
| fForceClose = fCloseLine = false; |
| fSegmentState = kEmptyContour_SegmentState; |
| #endif |
| // need to init enough to make next() harmlessly return kDone_Verb |
| fVerbs = nullptr; |
| fVerbStop = nullptr; |
| fNeedClose = false; |
| } |
| |
| SkPath::Iter::Iter(const SkPath& path, bool forceClose) { |
| this->setPath(path, forceClose); |
| } |
| |
| void SkPath::Iter::setPath(const SkPath& path, bool forceClose) { |
| fPts = path.fPathRef->points(); |
| fVerbs = path.fPathRef->verbsBegin(); |
| fVerbStop = path.fPathRef->verbsEnd(); |
| fConicWeights = path.fPathRef->conicWeights(); |
| if (fConicWeights) { |
| fConicWeights -= 1; // begin one behind |
| } |
| fLastPt.fX = fLastPt.fY = 0; |
| fMoveTo.fX = fMoveTo.fY = 0; |
| fForceClose = SkToU8(forceClose); |
| fNeedClose = false; |
| fSegmentState = kEmptyContour_SegmentState; |
| } |
| |
| bool SkPath::Iter::isClosedContour() const { |
| if (fVerbs == nullptr || fVerbs == fVerbStop) { |
| return false; |
| } |
| if (fForceClose) { |
| return true; |
| } |
| |
| const uint8_t* verbs = fVerbs; |
| const uint8_t* stop = fVerbStop; |
| |
| if (kMove_Verb == *verbs) { |
| verbs += 1; // skip the initial moveto |
| } |
| |
| while (verbs < stop) { |
| // verbs points one beyond the current verb, decrement first. |
| unsigned v = *verbs++; |
| if (kMove_Verb == v) { |
| break; |
| } |
| if (kClose_Verb == v) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| SkPath::Verb SkPath::Iter::autoClose(SkPoint pts[2]) { |
| SkASSERT(pts); |
| if (fLastPt != fMoveTo) { |
| // A special case: if both points are NaN, SkPoint::operation== returns |
| // false, but the iterator expects that they are treated as the same. |
| // (consider SkPoint is a 2-dimension float point). |
| if (SkScalarIsNaN(fLastPt.fX) || SkScalarIsNaN(fLastPt.fY) || |
| SkScalarIsNaN(fMoveTo.fX) || SkScalarIsNaN(fMoveTo.fY)) { |
| return kClose_Verb; |
| } |
| |
| pts[0] = fLastPt; |
| pts[1] = fMoveTo; |
| fLastPt = fMoveTo; |
| fCloseLine = true; |
| return kLine_Verb; |
| } else { |
| pts[0] = fMoveTo; |
| return kClose_Verb; |
| } |
| } |
| |
| const SkPoint& SkPath::Iter::cons_moveTo() { |
| if (fSegmentState == kAfterMove_SegmentState) { |
| // Set the first return pt to the move pt |
| fSegmentState = kAfterPrimitive_SegmentState; |
| return fMoveTo; |
| } |
| |
| SkASSERT(fSegmentState == kAfterPrimitive_SegmentState); |
| // Set the first return pt to the last pt of the previous primitive. |
| return fPts[-1]; |
| } |
| |
| SkPath::Verb SkPath::Iter::next(SkPoint ptsParam[4]) { |
| SkASSERT(ptsParam); |
| |
| if (fVerbs == fVerbStop) { |
| // Close the curve if requested and if there is some curve to close |
| if (fNeedClose && fSegmentState == kAfterPrimitive_SegmentState) { |
| if (kLine_Verb == this->autoClose(ptsParam)) { |
| return kLine_Verb; |
| } |
| fNeedClose = false; |
| return kClose_Verb; |
| } |
| return kDone_Verb; |
| } |
| |
| unsigned verb = *fVerbs++; |
| const SkPoint* SK_RESTRICT srcPts = fPts; |
| SkPoint* SK_RESTRICT pts = ptsParam; |
| |
| switch (verb) { |
| case kMove_Verb: |
| if (fNeedClose) { |
| fVerbs--; // move back one verb |
| verb = this->autoClose(pts); |
| if (verb == kClose_Verb) { |
| fNeedClose = false; |
| } |
| return (Verb)verb; |
| } |
| if (fVerbs == fVerbStop) { // might be a trailing moveto |
| return kDone_Verb; |
| } |
| fMoveTo = *srcPts; |
| pts[0] = *srcPts; |
| srcPts += 1; |
| fSegmentState = kAfterMove_SegmentState; |
| fLastPt = fMoveTo; |
| fNeedClose = fForceClose; |
| break; |
| case kLine_Verb: |
| pts[0] = this->cons_moveTo(); |
| pts[1] = srcPts[0]; |
| fLastPt = srcPts[0]; |
| fCloseLine = false; |
| srcPts += 1; |
| break; |
| case kConic_Verb: |
| fConicWeights += 1; |
| // fall-through |
| case kQuad_Verb: |
| pts[0] = this->cons_moveTo(); |
| memcpy(&pts[1], srcPts, 2 * sizeof(SkPoint)); |
| fLastPt = srcPts[1]; |
| srcPts += 2; |
| break; |
| case kCubic_Verb: |
| pts[0] = this->cons_moveTo(); |
| memcpy(&pts[1], srcPts, 3 * sizeof(SkPoint)); |
| fLastPt = srcPts[2]; |
| srcPts += 3; |
| break; |
| case kClose_Verb: |
| verb = this->autoClose(pts); |
| if (verb == kLine_Verb) { |
| fVerbs--; // move back one verb |
| } else { |
| fNeedClose = false; |
| fSegmentState = kEmptyContour_SegmentState; |
| } |
| fLastPt = fMoveTo; |
| break; |
| } |
| fPts = srcPts; |
| return (Verb)verb; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| #include "include/core/SkStream.h" |
| #include "include/core/SkString.h" |
| #include "src/core/SkStringUtils.h" |
| |
| static void append_params(SkString* str, const char label[], const SkPoint pts[], |
| int count, SkScalarAsStringType strType, SkScalar conicWeight = -12345) { |
| str->append(label); |
| str->append("("); |
| |
| const SkScalar* values = &pts[0].fX; |
| count *= 2; |
| |
| for (int i = 0; i < count; ++i) { |
| SkAppendScalar(str, values[i], strType); |
| if (i < count - 1) { |
| str->append(", "); |
| } |
| } |
| if (conicWeight != -12345) { |
| str->append(", "); |
| SkAppendScalar(str, conicWeight, strType); |
| } |
| str->append(");"); |
| if (kHex_SkScalarAsStringType == strType) { |
| str->append(" // "); |
| for (int i = 0; i < count; ++i) { |
| SkAppendScalarDec(str, values[i]); |
| if (i < count - 1) { |
| str->append(", "); |
| } |
| } |
| if (conicWeight >= 0) { |
| str->append(", "); |
| SkAppendScalarDec(str, conicWeight); |
| } |
| } |
| str->append("\n"); |
| } |
| |
| void SkPath::dump(SkWStream* wStream, bool forceClose, bool dumpAsHex) const { |
| SkScalarAsStringType asType = dumpAsHex ? kHex_SkScalarAsStringType : kDec_SkScalarAsStringType; |
| Iter iter(*this, forceClose); |
| SkPoint pts[4]; |
| Verb verb; |
| |
| SkString builder; |
| char const * const gFillTypeStrs[] = { |
| "Winding", |
| "EvenOdd", |
| "InverseWinding", |
| "InverseEvenOdd", |
| }; |
| builder.printf("path.setFillType(SkPath::k%s_FillType);\n", |
| gFillTypeStrs[(int) this->getFillType()]); |
| while ((verb = iter.next(pts)) != kDone_Verb) { |
| switch (verb) { |
| case kMove_Verb: |
| append_params(&builder, "path.moveTo", &pts[0], 1, asType); |
| break; |
| case kLine_Verb: |
| append_params(&builder, "path.lineTo", &pts[1], 1, asType); |
| break; |
| case kQuad_Verb: |
| append_params(&builder, "path.quadTo", &pts[1], 2, asType); |
| break; |
| case kConic_Verb: |
| append_params(&builder, "path.conicTo", &pts[1], 2, asType, iter.conicWeight()); |
| break; |
| case kCubic_Verb: |
| append_params(&builder, "path.cubicTo", &pts[1], 3, asType); |
| break; |
| case kClose_Verb: |
| builder.append("path.close();\n"); |
| break; |
| default: |
| SkDebugf(" path: UNKNOWN VERB %d, aborting dump...\n", verb); |
| verb = kDone_Verb; // stop the loop |
| break; |
| } |
| if (!wStream && builder.size()) { |
| SkDebugf("%s", builder.c_str()); |
| builder.reset(); |
| } |
| } |
| if (wStream) { |
| wStream->writeText(builder.c_str()); |
| } |
| } |
| |
| void SkPath::dump() const { |
| this->dump(nullptr, false, false); |
| } |
| |
| void SkPath::dumpHex() const { |
| this->dump(nullptr, false, true); |
| } |
| |
| |
| bool SkPath::isValidImpl() const { |
| if ((fFillType & ~3) != 0) { |
| return false; |
| } |
| |
| #ifdef SK_DEBUG_PATH |
| if (!fBoundsIsDirty) { |
| SkRect bounds; |
| |
| bool isFinite = compute_pt_bounds(&bounds, *fPathRef.get()); |
| if (SkToBool(fIsFinite) != isFinite) { |
| return false; |
| } |
| |
| if (fPathRef->countPoints() <= 1) { |
| // if we're empty, fBounds may be empty but translated, so we can't |
| // necessarily compare to bounds directly |
| // try path.addOval(2, 2, 2, 2) which is empty, but the bounds will |
| // be [2, 2, 2, 2] |
| if (!bounds.isEmpty() || !fBounds.isEmpty()) { |
| return false; |
| } |
| } else { |
| if (bounds.isEmpty()) { |
| if (!fBounds.isEmpty()) { |
| return false; |
| } |
| } else { |
| if (!fBounds.isEmpty()) { |
| if (!fBounds.contains(bounds)) { |
| return false; |
| } |
| } |
| } |
| } |
| } |
| #endif // SK_DEBUG_PATH |
| return true; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| #ifdef SK_LEGACY_PATH_CONVEXITY // for rebaselining Chrome |
| |
| static int sign(SkScalar x) { return x < 0; } |
| #define kValueNeverReturnedBySign 2 |
| |
| enum DirChange { |
| kLeft_DirChange, |
| kRight_DirChange, |
| kStraight_DirChange, |
| kBackwards_DirChange, |
| |
| kInvalid_DirChange |
| }; |
| |
| |
| static bool almost_equal(SkScalar compA, SkScalar compB) { |
| // The error epsilon was empirically derived; worse case round rects |
| // with a mid point outset by 2x float epsilon in tests had an error |
| // of 12. |
| const int epsilon = 16; |
| if (!SkScalarIsFinite(compA) || !SkScalarIsFinite(compB)) { |
| return false; |
| } |
| // no need to check for small numbers because SkPath::Iter has removed degenerate values |
| int aBits = SkFloatAs2sCompliment(compA); |
| int bBits = SkFloatAs2sCompliment(compB); |
| return aBits < bBits + epsilon && bBits < aBits + epsilon; |
| } |
| |
| // only valid for a single contour |
| struct Convexicator { |
| Convexicator() |
| : fPtCount(0) |
| , fConvexity(SkPath::kConvex_Convexity) |
| , fFirstDirection(SkPathPriv::kUnknown_FirstDirection) |
| , fIsFinite(true) |
| , fIsCurve(false) |
| , fBackwards(false) { |
| fExpectedDir = kInvalid_DirChange; |
| // warnings |
| fPriorPt.set(0,0); |
| fLastPt.set(0, 0); |
| fCurrPt.set(0, 0); |
| fLastVec.set(0, 0); |
| fFirstVec.set(0, 0); |
| |
| fDx = fDy = 0; |
| fSx = fSy = kValueNeverReturnedBySign; |
| } |
| |
| SkPath::Convexity getConvexity() const { return fConvexity; } |
| |
| /** The direction returned is only valid if the path is determined convex */ |
| SkPathPriv::FirstDirection getFirstDirection() const { return fFirstDirection; } |
| |
| void addPt(const SkPoint& pt) { |
| if (SkPath::kConcave_Convexity == fConvexity || !fIsFinite) { |
| return; |
| } |
| |
| if (0 == fPtCount) { |
| fCurrPt = pt; |
| ++fPtCount; |
| } else { |
| SkVector vec = pt - fCurrPt; |
| SkScalar lengthSqd = SkPointPriv::LengthSqd(vec); |
| if (!SkScalarIsFinite(lengthSqd)) { |
| fIsFinite = false; |
| } else if (lengthSqd) { |
| fPriorPt = fLastPt; |
| fLastPt = fCurrPt; |
| fCurrPt = pt; |
| if (++fPtCount == 2) { |
| fFirstVec = fLastVec = vec; |
| } else { |
| SkASSERT(fPtCount > 2); |
| this->addVec(vec); |
| } |
| |
| int sx = sign(vec.fX); |
| int sy = sign(vec.fY); |
| fDx += (sx != fSx); |
| fDy += (sy != fSy); |
| fSx = sx; |
| fSy = sy; |
| |
| if (fDx > 3 || fDy > 3) { |
| fConvexity = SkPath::kConcave_Convexity; |
| } |
| } |
| } |
| } |
| |
| void close() { |
| if (fPtCount > 2) { |
| this->addVec(fFirstVec); |
| } |
| } |
| |
| DirChange directionChange(const SkVector& curVec) { |
| SkScalar cross = SkPoint::CrossProduct(fLastVec, curVec); |
| |
| SkScalar smallest = SkTMin(fCurrPt.fX, SkTMin(fCurrPt.fY, SkTMin(fLastPt.fX, fLastPt.fY))); |
| SkScalar largest = SkTMax(fCurrPt.fX, SkTMax(fCurrPt.fY, SkTMax(fLastPt.fX, fLastPt.fY))); |
| largest = SkTMax(largest, -smallest); |
| |
| if (!almost_equal(largest, largest + cross)) { |
| int sign = SkScalarSignAsInt(cross); |
| if (sign) { |
| return (1 == sign) ? kRight_DirChange : kLeft_DirChange; |
| } |
| } |
| |
| if (cross) { |
| double dLastVecX = SkScalarToDouble(fLastPt.fX) - SkScalarToDouble(fPriorPt.fX); |
| double dLastVecY = SkScalarToDouble(fLastPt.fY) - SkScalarToDouble(fPriorPt.fY); |
| double dCurrVecX = SkScalarToDouble(fCurrPt.fX) - SkScalarToDouble(fLastPt.fX); |
| double dCurrVecY = SkScalarToDouble(fCurrPt.fY) - SkScalarToDouble(fLastPt.fY); |
| double dCross = dLastVecX * dCurrVecY - dLastVecY * dCurrVecX; |
| if (!approximately_zero_when_compared_to(dCross, SkScalarToDouble(largest))) { |
| int sign = SkScalarSignAsInt(SkDoubleToScalar(dCross)); |
| if (sign) { |
| return (1 == sign) ? kRight_DirChange : kLeft_DirChange; |
| } |
| } |
| } |
| |
| if (!SkScalarNearlyZero(SkPointPriv::LengthSqd(fLastVec), |
| SK_ScalarNearlyZero*SK_ScalarNearlyZero) && |
| !SkScalarNearlyZero(SkPointPriv::LengthSqd(curVec), |
| SK_ScalarNearlyZero*SK_ScalarNearlyZero) && |
| fLastVec.dot(curVec) < 0.0f) { |
| return kBackwards_DirChange; |
| } |
| |
| return kStraight_DirChange; |
| } |
| |
| bool hasBackwards() const { |
| return fBackwards; |
| } |
| |
| bool isFinite() const { |
| return fIsFinite; |
| } |
| |
| void setCurve(bool isCurve) { |
| fIsCurve = isCurve; |
| } |
| |
| private: |
| void addVec(const SkVector& vec) { |
| SkASSERT(vec.fX || vec.fY); |
| DirChange dir = this->directionChange(vec); |
| switch (dir) { |
| case kLeft_DirChange: // fall through |
| case kRight_DirChange: |
| if (kInvalid_DirChange == fExpectedDir) { |
| fExpectedDir = dir; |
| fFirstDirection = (kRight_DirChange == dir) ? SkPathPriv::kCW_FirstDirection |
| : SkPathPriv::kCCW_FirstDirection; |
| } else if (dir != fExpectedDir) { |
| fConvexity = SkPath::kConcave_Convexity; |
| fFirstDirection = SkPathPriv::kUnknown_FirstDirection; |
| } |
| fLastVec = vec; |
| break; |
| case kStraight_DirChange: |
| break; |
| case kBackwards_DirChange: |
| if (fIsCurve) { |
| // If any of the subsequent dir is non-backward, it'll be concave. |
| // Otherwise, it's still convex. |
| fExpectedDir = dir; |
| } |
| fLastVec = vec; |
| fBackwards = true; |
| break; |
| case kInvalid_DirChange: |
| SK_ABORT("Use of invalid direction change flag"); |
| break; |
| } |
| } |
| |
| SkPoint fPriorPt; |
| SkPoint fLastPt; |
| SkPoint fCurrPt; |
| // fLastVec does not necessarily start at fLastPt. We only advance it when the cross product |
| // value with the current vec is deemed to be of a significant value. |
| SkVector fLastVec, fFirstVec; |
| int fPtCount; // non-degenerate points |
| DirChange fExpectedDir; |
| SkPath::Convexity fConvexity; |
| SkPathPriv::FirstDirection fFirstDirection; |
| int fDx, fDy, fSx, fSy; |
| bool fIsFinite; |
| bool fIsCurve; |
| bool fBackwards; |
| }; |
| |
| SkPath::Convexity SkPath::internalGetConvexity() const { |
| // Sometimes we think we need to calculate convexity but another thread already did. |
| auto c = this->getConvexityOrUnknown(); |
| if (c != kUnknown_Convexity) { |
| return c; |
| } |
| |
| SkPoint pts[4]; |
| SkPath::Verb verb; |
| SkPath::Iter iter(*this, true); |
| |
| int contourCount = 0; |
| int count; |
| Convexicator state; |
| |
| if (!isFinite()) { |
| return kUnknown_Convexity; |
| } |
| while ((verb = iter.next(pts, false, false)) != SkPath::kDone_Verb) { |
| switch (verb) { |
| case kMove_Verb: |
| if (++contourCount > 1) { |
| this->setConvexity(kConcave_Convexity); |
| return kConcave_Convexity; |
| } |
| pts[1] = pts[0]; |
| // fall through |
| case kLine_Verb: |
| count = 1; |
| state.setCurve(false); |
| break; |
| case kQuad_Verb: |
| // fall through |
| case kConic_Verb: |
| // fall through |
| case kCubic_Verb: |
| count = 2 + (kCubic_Verb == verb); |
| // As an additional enhancement, this could set curve true only |
| // if the curve is nonlinear |
| state.setCurve(true); |
| break; |
| case kClose_Verb: |
| state.setCurve(false); |
| state.close(); |
| count = 0; |
| break; |
| default: |
| SkDEBUGFAIL("bad verb"); |
| this->setConvexity(kConcave_Convexity); |
| return kConcave_Convexity; |
| } |
| |
| for (int i = 1; i <= count; i++) { |
| state.addPt(pts[i]); |
| } |
| // early exit |
| if (!state.isFinite()) { |
| return kUnknown_Convexity; |
| } |
| if (kConcave_Convexity == state.getConvexity()) { |
| this->setConvexity(kConcave_Convexity); |
| return kConcave_Convexity; |
| } |
| } |
| this->setConvexity(state.getConvexity()); |
| |
| if (this->getConvexityOrUnknown() == kConvex_Convexity && |
| this->getFirstDirection() == SkPathPriv::kUnknown_FirstDirection) { |
| |
| if (state.getFirstDirection() == SkPathPriv::kUnknown_FirstDirection |
| && !this->getBounds().isEmpty() |
| && !state.hasBackwards()) { |
| this->setConvexity(Convexity::kConcave_Convexity); |
| } else { |
| this->setFirstDirection(state.getFirstDirection()); |
| } |
| } |
| return this->getConvexityOrUnknown(); |
| } |
| |
| #else |
| |
| static int sign(SkScalar x) { return x < 0; } |
| #define kValueNeverReturnedBySign 2 |
| |
| enum DirChange { |
| kUnknown_DirChange, |
| kLeft_DirChange, |
| kRight_DirChange, |
| kStraight_DirChange, |
| kBackwards_DirChange, // if double back, allow simple lines to be convex |
| kInvalid_DirChange |
| }; |
| |
| |
| static bool almost_equal(SkScalar compA, SkScalar compB) { |
| // The error epsilon was empirically derived; worse case round rects |
| // with a mid point outset by 2x float epsilon in tests had an error |
| // of 12. |
| const int epsilon = 16; |
| if (!SkScalarIsFinite(compA) || !SkScalarIsFinite(compB)) { |
| return false; |
| } |
| // no need to check for small numbers because SkPath::Iter has removed degenerate values |
| int aBits = SkFloatAs2sCompliment(compA); |
| int bBits = SkFloatAs2sCompliment(compB); |
| return aBits < bBits + epsilon && bBits < aBits + epsilon; |
| } |
| |
| // only valid for a single contour |
| struct Convexicator { |
| |
| /** The direction returned is only valid if the path is determined convex */ |
| SkPathPriv::FirstDirection getFirstDirection() const { return fFirstDirection; } |
| |
| void setMovePt(const SkPoint& pt) { |
| fPriorPt = fLastPt = fCurrPt = pt; |
| } |
| |
| bool addPt(const SkPoint& pt) { |
| if (fCurrPt == pt) { |
| return true; |
| } |
| fCurrPt = pt; |
| if (fPriorPt == fLastPt) { // should only be true for first non-zero vector |
| fLastVec = fCurrPt - fLastPt; |
| fFirstPt = pt; |
| } else if (!this->addVec(fCurrPt - fLastPt)) { |
| return false; |
| } |
| fPriorPt = fLastPt; |
| fLastPt = fCurrPt; |
| return true; |
| } |
| |
| static SkPath::Convexity BySign(const SkPoint points[], int count) { |
| const SkPoint* last = points + count; |
| SkPoint currPt = *points++; |
| SkPoint firstPt = currPt; |
| int dxes = 0; |
| int dyes = 0; |
| int lastSx = kValueNeverReturnedBySign; |
| int lastSy = kValueNeverReturnedBySign; |
| for (int outerLoop = 0; outerLoop < 2; ++outerLoop ) { |
| while (points != last) { |
| SkVector vec = *points - currPt; |
| if (!vec.isZero()) { |
| // give up if vector construction failed |
| if (!vec.isFinite()) { |
| return SkPath::kUnknown_Convexity; |
| } |
| int sx = sign(vec.fX); |
| int sy = sign(vec.fY); |
| dxes += (sx != lastSx); |
| dyes += (sy != lastSy); |
| if (dxes > 3 || dyes > 3) { |
| return SkPath::kConcave_Convexity; |
| } |
| lastSx = sx; |
| lastSy = sy; |
| } |
| currPt = *points++; |
| if (outerLoop) { |
| break; |
| } |
| } |
| points = &firstPt; |
| } |
| return SkPath::kConvex_Convexity; // that is, it may be convex, don't know yet |
| } |
| |
| bool close() { |
| return this->addPt(fFirstPt); |
| } |
| |
| bool isFinite() const { |
| return fIsFinite; |
| } |
| |
| int reversals() const { |
| return fReversals; |
| } |
| |
| private: |
| DirChange directionChange(const SkVector& curVec) { |
| SkScalar cross = SkPoint::CrossProduct(fLastVec, curVec); |
| if (!SkScalarIsFinite(cross)) { |
| return kUnknown_DirChange; |
| } |
| SkScalar smallest = SkTMin(fCurrPt.fX, SkTMin(fCurrPt.fY, SkTMin(fLastPt.fX, fLastPt.fY))); |
| SkScalar largest = SkTMax(fCurrPt.fX, SkTMax(fCurrPt.fY, SkTMax(fLastPt.fX, fLastPt.fY))); |
| largest = SkTMax(largest, -smallest); |
| |
| if (almost_equal(largest, largest + cross)) { |
| constexpr SkScalar nearlyZeroSqd = SK_ScalarNearlyZero * SK_ScalarNearlyZero; |
| if (SkScalarNearlyZero(SkPointPriv::LengthSqd(fLastVec), nearlyZeroSqd) || |
| SkScalarNearlyZero(SkPointPriv::LengthSqd(curVec), nearlyZeroSqd)) { |
| return kUnknown_DirChange; |
| } |
| return fLastVec.dot(curVec) < 0 ? kBackwards_DirChange : kStraight_DirChange; |
| } |
| return 1 == SkScalarSignAsInt(cross) ? kRight_DirChange : kLeft_DirChange; |
| } |
| |
| bool addVec(const SkVector& curVec) { |
| DirChange dir = this->directionChange(curVec); |
| switch (dir) { |
| case kLeft_DirChange: // fall through |
| case kRight_DirChange: |
| if (kInvalid_DirChange == fExpectedDir) { |
| fExpectedDir = dir; |
| fFirstDirection = (kRight_DirChange == dir) ? SkPathPriv::kCW_FirstDirection |
| : SkPathPriv::kCCW_FirstDirection; |
| } else if (dir != fExpectedDir) { |
| fFirstDirection = SkPathPriv::kUnknown_FirstDirection; |
| return false; |
| } |
| fLastVec = curVec; |
| break; |
| case kStraight_DirChange: |
| break; |
| case kBackwards_DirChange: |
| // allow path to reverse direction twice |
| // Given path.moveTo(0, 0); path.lineTo(1, 1); |
| // - 1st reversal: direction change formed by line (0,0 1,1), line (1,1 0,0) |
| // - 2nd reversal: direction change formed by line (1,1 0,0), line (0,0 1,1) |
| fLastVec = curVec; |
| return ++fReversals < 3; |
| case kUnknown_DirChange: |
| return (fIsFinite = false); |
| case kInvalid_DirChange: |
| SK_ABORT("Use of invalid direction change flag"); |
| break; |
| } |
| return true; |
| } |
| |
| SkPoint fFirstPt {0, 0}; |
| SkPoint fPriorPt {0, 0}; |
| SkPoint fLastPt {0, 0}; |
| SkPoint fCurrPt {0, 0}; |
| SkVector fLastVec {0, 0}; |
| DirChange fExpectedDir { kInvalid_DirChange }; |
| SkPathPriv::FirstDirection fFirstDirection { SkPathPriv::kUnknown_FirstDirection }; |
| int fReversals { 0 }; |
| bool fIsFinite { true }; |
| }; |
| |
| SkPath::Convexity SkPath::internalGetConvexity() const { |
| SkPoint pts[4]; |
| SkPath::Verb verb; |
| SkPath::Iter iter(*this, true); |
| auto setComputedConvexity = [=](Convexity convexity){ |
| SkASSERT(kUnknown_Convexity != convexity); |
| this->setConvexity(convexity); |
| return convexity; |
| }; |
| |
| // Check to see if path changes direction more than three times as quick concave test |
| int pointCount = this->countPoints(); |
| // last moveTo index may exceed point count if data comes from fuzzer (via SkImageFilter) |
| if (0 < fLastMoveToIndex && fLastMoveToIndex < pointCount) { |
| pointCount = fLastMoveToIndex; |
| } |
| if (pointCount > 3) { |
| const SkPoint* points = fPathRef->points(); |
| const SkPoint* last = &points[pointCount]; |
| // only consider the last of the initial move tos |
| while (SkPath::kMove_Verb == iter.next(pts)) { |
| ++points; |
| } |
| --points; |
| SkPath::Convexity convexity = Convexicator::BySign(points, (int) (last - points)); |
| if (SkPath::kConcave_Convexity == convexity) { |
| return setComputedConvexity(SkPath::kConcave_Convexity); |
| } else if (SkPath::kUnknown_Convexity == convexity) { |
| return SkPath::kUnknown_Convexity; |
| } |
| iter.setPath(*this, true); |
| } else if (!this->isFinite()) { |
| return kUnknown_Convexity; |
| } |
| |
| int contourCount = 0; |
| int count; |
| Convexicator state; |
| auto setFail = [=](){ |
| if (!state.isFinite()) { |
| return SkPath::kUnknown_Convexity; |
| } |
| return setComputedConvexity(SkPath::kConcave_Convexity); |
| }; |
| |
| while ((verb = iter.next(pts)) != SkPath::kDone_Verb) { |
| switch (verb) { |
| case kMove_Verb: |
| if (++contourCount > 1) { |
| return setComputedConvexity(kConcave_Convexity); |
| } |
| state.setMovePt(pts[0]); |
| count = 0; |
| break; |
| case kLine_Verb: |
| count = 1; |
| break; |
| case kQuad_Verb: |
| // fall through |
| case kConic_Verb: |
| count = 2; |
| break; |
| case kCubic_Verb: |
| count = 3; |
| break; |
| case kClose_Verb: |
| if (!state.close()) { |
| return setFail(); |
| } |
| count = 0; |
| break; |
| default: |
| SkDEBUGFAIL("bad verb"); |
| return setComputedConvexity(kConcave_Convexity); |
| } |
| for (int i = 1; i <= count; i++) { |
| if (!state.addPt(pts[i])) { |
| return setFail(); |
| } |
| } |
| } |
| |
| if (this->getFirstDirection() == SkPathPriv::kUnknown_FirstDirection) { |
| if (state.getFirstDirection() == SkPathPriv::kUnknown_FirstDirection |
| && !this->getBounds().isEmpty()) { |
| return setComputedConvexity(state.reversals() < 3 ? |
| kConvex_Convexity : kConcave_Convexity); |
| } |
| this->setFirstDirection(state.getFirstDirection()); |
| } |
| return setComputedConvexity(kConvex_Convexity); |
| } |
| |
| bool SkPathPriv::IsConvex(const SkPoint points[], int count) { |
| SkPath::Convexity convexity = Convexicator::BySign(points, count); |
| if (SkPath::kConvex_Convexity != convexity) { |
| return false; |
| } |
| Convexicator state; |
| state.setMovePt(points[0]); |
| for (int i = 1; i < count; i++) { |
| if (!state.addPt(points[i])) { |
| return false; |
| } |
| } |
| if (!state.addPt(points[0])) { |
| return false; |
| } |
| if (!state.close()) { |
| return false; |
| } |
| return state.getFirstDirection() != SkPathPriv::kUnknown_FirstDirection |
| || state.reversals() < 3; |
| } |
| |
| #endif |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| class ContourIter { |
| public: |
| ContourIter(const SkPathRef& pathRef); |
| |
| bool done() const { return fDone; } |
| // if !done() then these may be called |
| int count() const { return fCurrPtCount; } |
| const SkPoint* pts() const { return fCurrPt; } |
| void next(); |
| |
| private: |
| int fCurrPtCount; |
| const SkPoint* fCurrPt; |
| const uint8_t* fCurrVerb; |
| const uint8_t* fStopVerbs; |
| const SkScalar* fCurrConicWeight; |
| bool fDone; |
| SkDEBUGCODE(int fContourCounter;) |
| }; |
| |
| ContourIter::ContourIter(const SkPathRef& pathRef) { |
| fStopVerbs = pathRef.verbsEnd(); |
| fDone = false; |
| fCurrPt = pathRef.points(); |
| fCurrVerb = pathRef.verbsBegin(); |
| fCurrConicWeight = pathRef.conicWeights(); |
| fCurrPtCount = 0; |
| SkDEBUGCODE(fContourCounter = 0;) |
| this->next(); |
| } |
| |
| void ContourIter::next() { |
| if (fCurrVerb >= fStopVerbs) { |
| fDone = true; |
| } |
| if (fDone) { |
| return; |
| } |
| |
| // skip pts of prev contour |
| fCurrPt += fCurrPtCount; |
| |
| SkASSERT(SkPath::kMove_Verb == fCurrVerb[0]); |
| int ptCount = 1; // moveTo |
| const uint8_t* verbs = fCurrVerb; |
| |
| for (verbs++; verbs < fStopVerbs; verbs++) { |
| switch (*verbs) { |
| case SkPath::kMove_Verb: |
| goto CONTOUR_END; |
| case SkPath::kLine_Verb: |
| ptCount += 1; |
| break; |
| case SkPath::kConic_Verb: |
| fCurrConicWeight += 1; |
| // fall-through |
| case SkPath::kQuad_Verb: |
| ptCount += 2; |
| break; |
| case SkPath::kCubic_Verb: |
| ptCount += 3; |
| break; |
| case SkPath::kClose_Verb: |
| break; |
| default: |
| SkDEBUGFAIL("unexpected verb"); |
| break; |
| } |
| } |
| CONTOUR_END: |
| fCurrPtCount = ptCount; |
| fCurrVerb = verbs; |
| SkDEBUGCODE(++fContourCounter;) |
| } |
| |
| // returns cross product of (p1 - p0) and (p2 - p0) |
| static SkScalar cross_prod(const SkPoint& p0, const SkPoint& p1, const SkPoint& p2) { |
| SkScalar cross = SkPoint::CrossProduct(p1 - p0, p2 - p0); |
| // We may get 0 when the above subtracts underflow. We expect this to be |
| // very rare and lazily promote to double. |
| if (0 == cross) { |
| double p0x = SkScalarToDouble(p0.fX); |
| double p0y = SkScalarToDouble(p0.fY); |
| |
| double p1x = SkScalarToDouble(p1.fX); |
| double p1y = SkScalarToDouble(p1.fY); |
| |
| double p2x = SkScalarToDouble(p2.fX); |
| double p2y = SkScalarToDouble(p2.fY); |
| |
| cross = SkDoubleToScalar((p1x - p0x) * (p2y - p0y) - |
| (p1y - p0y) * (p2x - p0x)); |
| |
| } |
| return cross; |
| } |
| |
| // Returns the first pt with the maximum Y coordinate |
| static int find_max_y(const SkPoint pts[], int count) { |
| SkASSERT(count > 0); |
| SkScalar max = pts[0].fY; |
| int firstIndex = 0; |
| for (int i = 1; i < count; ++i) { |
| SkScalar y = pts[i].fY; |
| if (y > max) { |
| max = y; |
| firstIndex = i; |
| } |
| } |
| return firstIndex; |
| } |
| |
| static int find_diff_pt(const SkPoint pts[], int index, int n, int inc) { |
| int i = index; |
| for (;;) { |
| i = (i + inc) % n; |
| if (i == index) { // we wrapped around, so abort |
| break; |
| } |
| if (pts[index] != pts[i]) { // found a different point, success! |
| break; |
| } |
| } |
| return i; |
| } |
| |
| /** |
| * Starting at index, and moving forward (incrementing), find the xmin and |
| * xmax of the contiguous points that have the same Y. |
| */ |
| static int find_min_max_x_at_y(const SkPoint pts[], int index, int n, |
| int* maxIndexPtr) { |
| const SkScalar y = pts[index].fY; |
| SkScalar min = pts[index].fX; |
| SkScalar max = min; |
| int minIndex = index; |
| int maxIndex = index; |
| for (int i = index + 1; i < n; ++i) { |
| if (pts[i].fY != y) { |
| break; |
| } |
| SkScalar x = pts[i].fX; |
| if (x < min) { |
| min = x; |
| minIndex = i; |
| } else if (x > max) { |
| max = x; |
| maxIndex = i; |
| } |
| } |
| *maxIndexPtr = maxIndex; |
| return minIndex; |
| } |
| |
| static void crossToDir(SkScalar cross, SkPathPriv::FirstDirection* dir) { |
| *dir = cross > 0 ? SkPathPriv::kCW_FirstDirection : SkPathPriv::kCCW_FirstDirection; |
| } |
| |
| /* |
| * We loop through all contours, and keep the computed cross-product of the |
| * contour that contained the global y-max. If we just look at the first |
| * contour, we may find one that is wound the opposite way (correctly) since |
| * it is the interior of a hole (e.g. 'o'). Thus we must find the contour |
| * that is outer most (or at least has the global y-max) before we can consider |
| * its cross product. |
| */ |
| bool SkPathPriv::CheapComputeFirstDirection(const SkPath& path, FirstDirection* dir) { |
| auto d = path.getFirstDirection(); |
| if (d != kUnknown_FirstDirection) { |
| *dir = static_cast<FirstDirection>(d); |
| return true; |
| } |
| |
| // We don't want to pay the cost for computing convexity if it is unknown, |
| // so we call getConvexityOrUnknown() instead of isConvex(). |
| if (path.getConvexityOrUnknown() == SkPath::kConvex_Convexity) { |
| SkASSERT(path.getFirstDirection() == kUnknown_FirstDirection); |
| *dir = static_cast<FirstDirection>(path.getFirstDirection()); |
| return false; |
| } |
| |
| ContourIter iter(*path.fPathRef.get()); |
| |
| // initialize with our logical y-min |
| SkScalar ymax = path.getBounds().fTop; |
| SkScalar ymaxCross = 0; |
| |
| for (; !iter.done(); iter.next()) { |
| int n = iter.count(); |
| if (n < 3) { |
| continue; |
| } |
| |
| const SkPoint* pts = iter.pts(); |
| SkScalar cross = 0; |
| int index = find_max_y(pts, n); |
| if (pts[index].fY < ymax) { |
| continue; |
| } |
| |
| // If there is more than 1 distinct point at the y-max, we take the |
| // x-min and x-max of them and just subtract to compute the dir. |
| if (pts[(index + 1) % n].fY == pts[index].fY) { |
| int maxIndex; |
| int minIndex = find_min_max_x_at_y(pts, index, n, &maxIndex); |
| if (minIndex == maxIndex) { |
| goto TRY_CROSSPROD; |
| } |
| SkASSERT(pts[minIndex].fY == pts[index].fY); |
| SkASSERT(pts[maxIndex].fY == pts[index].fY); |
| SkASSERT(pts[minIndex].fX <= pts[maxIndex].fX); |
| // we just subtract the indices, and let that auto-convert to |
| // SkScalar, since we just want - or + to signal the direction. |
| cross = minIndex - maxIndex; |
| } else { |
| TRY_CROSSPROD: |
| // Find a next and prev index to use for the cross-product test, |
| // but we try to find pts that form non-zero vectors from pts[index] |
| // |
| // Its possible that we can't find two non-degenerate vectors, so |
| // we have to guard our search (e.g. all the pts could be in the |
| // same place). |
| |
| // we pass n - 1 instead of -1 so we don't foul up % operator by |
| // passing it a negative LH argument. |
| int prev = find_diff_pt(pts, index, n, n - 1); |
| if (prev == index) { |
| // completely degenerate, skip to next contour |
| continue; |
| } |
| int next = find_diff_pt(pts, index, n, 1); |
| SkASSERT(next != index); |
| cross = cross_prod(pts[prev], pts[index], pts[next]); |
| // if we get a zero and the points are horizontal, then we look at the spread in |
| // x-direction. We really should continue to walk away from the degeneracy until |
| // there is a divergence. |
| if (0 == cross && pts[prev].fY == pts[index].fY && pts[next].fY == pts[index].fY) { |
| // construct the subtract so we get the correct Direction below |
| cross = pts[index].fX - pts[next].fX; |
| } |
| } |
| |
| if (cross) { |
| // record our best guess so far |
| ymax = pts[index].fY; |
| ymaxCross = cross; |
|