reed | 026beb5 | 2015-06-10 14:23:15 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2015 Google Inc. |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license that can be |
| 5 | * found in the LICENSE file. |
| 6 | */ |
| 7 | |
| 8 | #ifndef SkPathPriv_DEFINED |
| 9 | #define SkPathPriv_DEFINED |
| 10 | |
| 11 | #include "SkPath.h" |
| 12 | |
| 13 | class SkPathPriv { |
| 14 | public: |
Cary Clark | b201544 | 2017-09-14 10:31:36 -0400 | [diff] [blame] | 15 | #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK |
| 16 | static const int kPathRefGenIDBitCnt = 30; // leave room for the fill type (skbug.com/1762) |
| 17 | #else |
| 18 | static const int kPathRefGenIDBitCnt = 32; |
| 19 | #endif |
| 20 | |
reed | 026beb5 | 2015-06-10 14:23:15 -0700 | [diff] [blame] | 21 | enum FirstDirection { |
| 22 | kCW_FirstDirection, // == SkPath::kCW_Direction |
| 23 | kCCW_FirstDirection, // == SkPath::kCCW_Direction |
| 24 | kUnknown_FirstDirection, |
| 25 | }; |
| 26 | |
| 27 | static FirstDirection AsFirstDirection(SkPath::Direction dir) { |
| 28 | // since we agree numerically for the values in Direction, we can just cast. |
| 29 | return (FirstDirection)dir; |
| 30 | } |
| 31 | |
| 32 | /** |
| 33 | * Return the opposite of the specified direction. kUnknown is its own |
| 34 | * opposite. |
| 35 | */ |
| 36 | static FirstDirection OppositeFirstDirection(FirstDirection dir) { |
| 37 | static const FirstDirection gOppositeDir[] = { |
halcanary | 9d524f2 | 2016-03-29 09:03:52 -0700 | [diff] [blame] | 38 | kCCW_FirstDirection, kCW_FirstDirection, kUnknown_FirstDirection, |
reed | 026beb5 | 2015-06-10 14:23:15 -0700 | [diff] [blame] | 39 | }; |
| 40 | return gOppositeDir[dir]; |
| 41 | } |
| 42 | |
| 43 | /** |
| 44 | * Tries to quickly compute the direction of the first non-degenerate |
| 45 | * contour. If it can be computed, return true and set dir to that |
| 46 | * direction. If it cannot be (quickly) determined, return false and ignore |
| 47 | * the dir parameter. If the direction was determined, it is cached to make |
| 48 | * subsequent calls return quickly. |
| 49 | */ |
| 50 | static bool CheapComputeFirstDirection(const SkPath&, FirstDirection* dir); |
| 51 | |
| 52 | /** |
| 53 | * Returns true if the path's direction can be computed via |
| 54 | * cheapComputDirection() and if that computed direction matches the |
| 55 | * specified direction. If dir is kUnknown, returns true if the direction |
| 56 | * cannot be computed. |
| 57 | */ |
| 58 | static bool CheapIsFirstDirection(const SkPath& path, FirstDirection dir) { |
| 59 | FirstDirection computedDir = kUnknown_FirstDirection; |
| 60 | (void)CheapComputeFirstDirection(path, &computedDir); |
| 61 | return computedDir == dir; |
| 62 | } |
| 63 | |
ethannicholas | c88cb89 | 2015-12-15 11:01:12 -0800 | [diff] [blame] | 64 | static bool IsClosedSingleContour(const SkPath& path) { |
| 65 | int verbCount = path.countVerbs(); |
| 66 | if (verbCount == 0) |
| 67 | return false; |
| 68 | int moveCount = 0; |
| 69 | auto verbs = path.fPathRef->verbs(); |
| 70 | for (int i = 0; i < verbCount; i++) { |
| 71 | switch (verbs[~i]) { // verbs are stored backwards; we use [~i] to get the i'th verb |
| 72 | case SkPath::Verb::kMove_Verb: |
| 73 | moveCount += 1; |
| 74 | if (moveCount > 1) { |
| 75 | return false; |
| 76 | } |
| 77 | break; |
| 78 | case SkPath::Verb::kClose_Verb: |
| 79 | if (i == verbCount - 1) { |
| 80 | return true; |
| 81 | } |
| 82 | return false; |
| 83 | default: break; |
| 84 | } |
| 85 | } |
| 86 | return false; |
fmalita | bd5d7e7 | 2015-06-26 07:18:24 -0700 | [diff] [blame] | 87 | } |
senorblanco | 84cd621 | 2015-08-04 10:01:58 -0700 | [diff] [blame] | 88 | |
| 89 | static void AddGenIDChangeListener(const SkPath& path, SkPathRef::GenIDChangeListener* listener) { |
| 90 | path.fPathRef->addGenIDChangeListener(listener); |
| 91 | } |
bsalomon | edc743a | 2016-06-01 09:42:31 -0700 | [diff] [blame] | 92 | |
| 93 | /** |
| 94 | * This returns true for a rect that begins and ends at the same corner and has either a move |
| 95 | * followed by four lines or a move followed by 3 lines and a close. None of the parameters are |
| 96 | * optional. This does not permit degenerate line or point rectangles. |
| 97 | */ |
| 98 | static bool IsSimpleClosedRect(const SkPath& path, SkRect* rect, SkPath::Direction* direction, |
| 99 | unsigned* start); |
bsalomon | 21af9ca | 2016-08-25 12:29:23 -0700 | [diff] [blame] | 100 | |
| 101 | /** |
| 102 | * Creates a path from arc params using the semantics of SkCanvas::drawArc. This function |
| 103 | * assumes empty ovals and zero sweeps have already been filtered out. |
| 104 | */ |
| 105 | static void CreateDrawArcPath(SkPath* path, const SkRect& oval, SkScalar startAngle, |
| 106 | SkScalar sweepAngle, bool useCenter, bool isFillNoPathEffect); |
bsalomon | 67fa4e3 | 2016-09-21 08:26:57 -0700 | [diff] [blame] | 107 | |
| 108 | /** |
Chris Dalton | 1b0126b | 2017-06-15 11:41:37 -0600 | [diff] [blame] | 109 | * Returns a C++11-iterable object that traverses a path's verbs in order. e.g: |
| 110 | * |
| 111 | * for (SkPath::Verb verb : SkPathPriv::Verbs(path)) { |
| 112 | * ... |
| 113 | * } |
| 114 | */ |
| 115 | struct Verbs { |
| 116 | public: |
| 117 | Verbs(const SkPath& path) : fPathRef(path.fPathRef.get()) {} |
| 118 | struct Iter { |
| 119 | void operator++() { --fVerb; } // verbs are laid out backwards in memory. |
| 120 | bool operator!=(const Iter& b) { return fVerb != b.fVerb; } |
| 121 | SkPath::Verb operator*() { return static_cast<SkPath::Verb>(*fVerb); } |
| 122 | const uint8_t* fVerb; |
| 123 | }; |
| 124 | Iter begin() { return Iter{fPathRef->verbs() - 1}; } |
| 125 | Iter end() { return Iter{fPathRef->verbs() - fPathRef->countVerbs() - 1}; } |
| 126 | private: |
| 127 | Verbs(const Verbs&) = delete; |
| 128 | Verbs& operator=(const Verbs&) = delete; |
| 129 | SkPathRef* fPathRef; |
| 130 | }; |
| 131 | |
| 132 | /** |
bsalomon | 67fa4e3 | 2016-09-21 08:26:57 -0700 | [diff] [blame] | 133 | * Returns a pointer to the verb data. Note that the verbs are stored backwards in memory and |
| 134 | * thus the returned pointer is the last verb. |
| 135 | */ |
| 136 | static const uint8_t* VerbData(const SkPath& path) { |
| 137 | return path.fPathRef->verbsMemBegin(); |
| 138 | } |
| 139 | |
| 140 | /** Returns a raw pointer to the path points */ |
| 141 | static const SkPoint* PointData(const SkPath& path) { |
| 142 | return path.fPathRef->points(); |
| 143 | } |
| 144 | |
| 145 | /** Returns the number of conic weights in the path */ |
| 146 | static int ConicWeightCnt(const SkPath& path) { |
| 147 | return path.fPathRef->countWeights(); |
| 148 | } |
| 149 | |
| 150 | /** Returns a raw pointer to the path conic weights. */ |
| 151 | static const SkScalar* ConicWeightData(const SkPath& path) { |
| 152 | return path.fPathRef->conicWeights(); |
| 153 | } |
reed | 026beb5 | 2015-06-10 14:23:15 -0700 | [diff] [blame] | 154 | }; |
| 155 | |
| 156 | #endif |