1 | /* |
2 | * Copyright 2006 The Android Open Source Project |
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 SkPath_DEFINED |
9 | #define SkPath_DEFINED |
10 | |
11 | #include "include/core/SkMatrix.h" |
12 | #include "include/core/SkPathTypes.h" |
13 | #include "include/private/SkPathRef.h" |
14 | #include "include/private/SkTo.h" |
15 | |
16 | #include <initializer_list> |
17 | |
18 | class SkAutoPathBoundsUpdate; |
19 | class SkData; |
20 | class SkRRect; |
21 | struct SkPathView; |
22 | class SkWStream; |
23 | |
24 | // WIP -- define this locally, and fix call-sites to use SkPathBuilder (skbug.com/9000) |
25 | //#define SK_HIDE_PATH_EDIT_METHODS |
26 | |
27 | /** \class SkPath |
28 | SkPath contain geometry. SkPath may be empty, or contain one or more verbs that |
29 | outline a figure. SkPath always starts with a move verb to a Cartesian coordinate, |
30 | and may be followed by additional verbs that add lines or curves. |
31 | Adding a close verb makes the geometry into a continuous loop, a closed contour. |
32 | SkPath may contain any number of contours, each beginning with a move verb. |
33 | |
34 | SkPath contours may contain only a move verb, or may also contain lines, |
35 | quadratic beziers, conics, and cubic beziers. SkPath contours may be open or |
36 | closed. |
37 | |
38 | When used to draw a filled area, SkPath describes whether the fill is inside or |
39 | outside the geometry. SkPath also describes the winding rule used to fill |
40 | overlapping contours. |
41 | |
42 | Internally, SkPath lazily computes metrics likes bounds and convexity. Call |
43 | SkPath::updateBoundsCache to make SkPath thread safe. |
44 | */ |
45 | class SK_API SkPath { |
46 | public: |
47 | /** |
48 | * Create a new path with the specified segments. |
49 | * |
50 | * The points and weights arrays are read in order, based on the sequence of verbs. |
51 | * |
52 | * Move 1 point |
53 | * Line 1 point |
54 | * Quad 2 points |
55 | * Conic 2 points and 1 weight |
56 | * Cubic 3 points |
57 | * Close 0 points |
58 | * |
59 | * If an illegal sequence of verbs is encountered, or the specified number of points |
60 | * or weights is not sufficient given the verbs, an empty Path is returned. |
61 | * |
62 | * A legal sequence of verbs consists of any number of Contours. A contour always begins |
63 | * with a Move verb, followed by 0 or more segments: Line, Quad, Conic, Cubic, followed |
64 | * by an optional Close. |
65 | */ |
66 | static SkPath Make(const SkPoint[], int pointCount, |
67 | const uint8_t[], int verbCount, |
68 | const SkScalar[], int conicWeightCount, |
69 | SkPathFillType, bool isVolatile = false); |
70 | |
71 | static SkPath Rect(const SkRect&, SkPathDirection dir = SkPathDirection::kCW); |
72 | static SkPath Oval(const SkRect&, SkPathDirection dir = SkPathDirection::kCW); |
73 | static SkPath Circle(SkScalar center_x, SkScalar center_y, SkScalar radius, |
74 | SkPathDirection dir = SkPathDirection::kCW); |
75 | static SkPath RRect(const SkRRect&, SkPathDirection dir = SkPathDirection::kCW); |
76 | |
77 | static SkPath Polygon(const SkPoint pts[], int count, bool isClosed, |
78 | SkPathFillType = SkPathFillType::kWinding, |
79 | bool isVolatile = false); |
80 | |
81 | static SkPath Polygon(const std::initializer_list<SkPoint>& list, bool isClosed, |
82 | SkPathFillType fillType = SkPathFillType::kWinding, |
83 | bool isVolatile = false) { |
84 | return Polygon(list.begin(), SkToInt(list.size()), isClosed, fillType, isVolatile); |
85 | } |
86 | |
87 | static SkPath Line(const SkPoint a, const SkPoint b) { |
88 | return Polygon({a, b}, false); |
89 | } |
90 | |
91 | /** Constructs an empty SkPath. By default, SkPath has no verbs, no SkPoint, and no weights. |
92 | FillType is set to kWinding. |
93 | |
94 | @return empty SkPath |
95 | |
96 | example: https://fiddle.skia.org/c/@Path_empty_constructor |
97 | */ |
98 | SkPath(); |
99 | |
100 | /** Constructs a copy of an existing path. |
101 | Copy constructor makes two paths identical by value. Internally, path and |
102 | the returned result share pointer values. The underlying verb array, SkPoint array |
103 | and weights are copied when modified. |
104 | |
105 | Creating a SkPath copy is very efficient and never allocates memory. |
106 | SkPath are always copied by value from the interface; the underlying shared |
107 | pointers are not exposed. |
108 | |
109 | @param path SkPath to copy by value |
110 | @return copy of SkPath |
111 | |
112 | example: https://fiddle.skia.org/c/@Path_copy_const_SkPath |
113 | */ |
114 | SkPath(const SkPath& path); |
115 | |
116 | /** Releases ownership of any shared data and deletes data if SkPath is sole owner. |
117 | |
118 | example: https://fiddle.skia.org/c/@Path_destructor |
119 | */ |
120 | ~SkPath(); |
121 | |
122 | /** Constructs a copy of an existing path. |
123 | SkPath assignment makes two paths identical by value. Internally, assignment |
124 | shares pointer values. The underlying verb array, SkPoint array and weights |
125 | are copied when modified. |
126 | |
127 | Copying SkPath by assignment is very efficient and never allocates memory. |
128 | SkPath are always copied by value from the interface; the underlying shared |
129 | pointers are not exposed. |
130 | |
131 | @param path verb array, SkPoint array, weights, and SkPath::FillType to copy |
132 | @return SkPath copied by value |
133 | |
134 | example: https://fiddle.skia.org/c/@Path_copy_operator |
135 | */ |
136 | SkPath& operator=(const SkPath& path); |
137 | |
138 | /** Compares a and b; returns true if SkPath::FillType, verb array, SkPoint array, and weights |
139 | are equivalent. |
140 | |
141 | @param a SkPath to compare |
142 | @param b SkPath to compare |
143 | @return true if SkPath pair are equivalent |
144 | */ |
145 | friend SK_API bool operator==(const SkPath& a, const SkPath& b); |
146 | |
147 | /** Compares a and b; returns true if SkPath::FillType, verb array, SkPoint array, and weights |
148 | are not equivalent. |
149 | |
150 | @param a SkPath to compare |
151 | @param b SkPath to compare |
152 | @return true if SkPath pair are not equivalent |
153 | */ |
154 | friend bool operator!=(const SkPath& a, const SkPath& b) { |
155 | return !(a == b); |
156 | } |
157 | |
158 | /** Returns true if SkPath contain equal verbs and equal weights. |
159 | If SkPath contain one or more conics, the weights must match. |
160 | |
161 | conicTo() may add different verbs depending on conic weight, so it is not |
162 | trivial to interpolate a pair of SkPath containing conics with different |
163 | conic weight values. |
164 | |
165 | @param compare SkPath to compare |
166 | @return true if SkPath verb array and weights are equivalent |
167 | |
168 | example: https://fiddle.skia.org/c/@Path_isInterpolatable |
169 | */ |
170 | bool isInterpolatable(const SkPath& compare) const; |
171 | |
172 | /** Interpolates between SkPath with SkPoint array of equal size. |
173 | Copy verb array and weights to out, and set out SkPoint array to a weighted |
174 | average of this SkPoint array and ending SkPoint array, using the formula: |
175 | (Path Point * weight) + ending Point * (1 - weight). |
176 | |
177 | weight is most useful when between zero (ending SkPoint array) and |
178 | one (this Point_Array); will work with values outside of this |
179 | range. |
180 | |
181 | interpolate() returns false and leaves out unchanged if SkPoint array is not |
182 | the same size as ending SkPoint array. Call isInterpolatable() to check SkPath |
183 | compatibility prior to calling interpolate(). |
184 | |
185 | @param ending SkPoint array averaged with this SkPoint array |
186 | @param weight contribution of this SkPoint array, and |
187 | one minus contribution of ending SkPoint array |
188 | @param out SkPath replaced by interpolated averages |
189 | @return true if SkPath contain same number of SkPoint |
190 | |
191 | example: https://fiddle.skia.org/c/@Path_interpolate |
192 | */ |
193 | bool interpolate(const SkPath& ending, SkScalar weight, SkPath* out) const; |
194 | |
195 | /** Returns SkPathFillType, the rule used to fill SkPath. |
196 | |
197 | @return current SkPathFillType setting |
198 | */ |
199 | SkPathFillType getFillType() const { return (SkPathFillType)fFillType; } |
200 | |
201 | /** Sets FillType, the rule used to fill SkPath. While there is no check |
202 | that ft is legal, values outside of FillType are not supported. |
203 | */ |
204 | void setFillType(SkPathFillType ft) { |
205 | fFillType = SkToU8(ft); |
206 | } |
207 | |
208 | /** Returns if FillType describes area outside SkPath geometry. The inverse fill area |
209 | extends indefinitely. |
210 | |
211 | @return true if FillType is kInverseWinding or kInverseEvenOdd |
212 | */ |
213 | bool isInverseFillType() const { return SkPathFillType_IsInverse(this->getFillType()); } |
214 | |
215 | /** Replaces FillType with its inverse. The inverse of FillType describes the area |
216 | unmodified by the original FillType. |
217 | */ |
218 | void toggleInverseFillType() { |
219 | fFillType ^= 2; |
220 | } |
221 | |
222 | /** Returns the comvexity type, computing if needed. Never returns kUnknown. |
223 | @return path's convexity type (convex or concave) |
224 | */ |
225 | SkPathConvexityType getConvexityType() const { |
226 | SkPathConvexityType convexity = this->getConvexityTypeOrUnknown(); |
227 | if (convexity != SkPathConvexityType::kUnknown) { |
228 | return convexity; |
229 | } |
230 | return this->internalGetConvexity(); |
231 | } |
232 | |
233 | /** If the path's convexity is already known, return it, else return kUnknown. |
234 | * If you always want to know the convexity, even if that means having to compute it, |
235 | * call getConvexitytype(). |
236 | * |
237 | * @return known convexity, or kUnknown |
238 | */ |
239 | SkPathConvexityType getConvexityTypeOrUnknown() const { |
240 | return (SkPathConvexityType)fConvexity.load(std::memory_order_relaxed); |
241 | } |
242 | |
243 | /** Stores a convexity type for this path. This is what will be returned if |
244 | * getConvexityTypeOrUnknown() is called. If you pass kUnknown, then if getContexityType() |
245 | * is called, the real convexity will be computed. |
246 | * |
247 | * example: https://fiddle.skia.org/c/@Path_setConvexity |
248 | */ |
249 | void setConvexityType(SkPathConvexityType convexity); |
250 | |
251 | /** Returns true if the path is convex. If necessary, it will first compute the convexity. |
252 | */ |
253 | bool isConvex() const { |
254 | return SkPathConvexityType::kConvex == this->getConvexityType(); |
255 | } |
256 | |
257 | /** Returns true if this path is recognized as an oval or circle. |
258 | |
259 | bounds receives bounds of oval. |
260 | |
261 | bounds is unmodified if oval is not found. |
262 | |
263 | @param bounds storage for bounding SkRect of oval; may be nullptr |
264 | @return true if SkPath is recognized as an oval or circle |
265 | |
266 | example: https://fiddle.skia.org/c/@Path_isOval |
267 | */ |
268 | bool isOval(SkRect* bounds) const; |
269 | |
270 | /** Returns true if path is representable as SkRRect. |
271 | Returns false if path is representable as oval, circle, or SkRect. |
272 | |
273 | rrect receives bounds of SkRRect. |
274 | |
275 | rrect is unmodified if SkRRect is not found. |
276 | |
277 | @param rrect storage for bounding SkRect of SkRRect; may be nullptr |
278 | @return true if SkPath contains only SkRRect |
279 | |
280 | example: https://fiddle.skia.org/c/@Path_isRRect |
281 | */ |
282 | bool isRRect(SkRRect* rrect) const; |
283 | |
284 | /** Sets SkPath to its initial state. |
285 | Removes verb array, SkPoint array, and weights, and sets FillType to kWinding. |
286 | Internal storage associated with SkPath is released. |
287 | |
288 | @return reference to SkPath |
289 | |
290 | example: https://fiddle.skia.org/c/@Path_reset |
291 | */ |
292 | SkPath& reset(); |
293 | |
294 | /** Sets SkPath to its initial state, preserving internal storage. |
295 | Removes verb array, SkPoint array, and weights, and sets FillType to kWinding. |
296 | Internal storage associated with SkPath is retained. |
297 | |
298 | Use rewind() instead of reset() if SkPath storage will be reused and performance |
299 | is critical. |
300 | |
301 | @return reference to SkPath |
302 | |
303 | example: https://fiddle.skia.org/c/@Path_rewind |
304 | */ |
305 | SkPath& rewind(); |
306 | |
307 | /** Returns if SkPath is empty. |
308 | Empty SkPath may have FillType but has no SkPoint, SkPath::Verb, or conic weight. |
309 | SkPath() constructs empty SkPath; reset() and rewind() make SkPath empty. |
310 | |
311 | @return true if the path contains no SkPath::Verb array |
312 | */ |
313 | bool isEmpty() const { |
314 | SkDEBUGCODE(this->validate();) |
315 | return 0 == fPathRef->countVerbs(); |
316 | } |
317 | |
318 | /** Returns if contour is closed. |
319 | Contour is closed if SkPath SkPath::Verb array was last modified by close(). When stroked, |
320 | closed contour draws SkPaint::Join instead of SkPaint::Cap at first and last SkPoint. |
321 | |
322 | @return true if the last contour ends with a kClose_Verb |
323 | |
324 | example: https://fiddle.skia.org/c/@Path_isLastContourClosed |
325 | */ |
326 | bool isLastContourClosed() const; |
327 | |
328 | /** Returns true for finite SkPoint array values between negative SK_ScalarMax and |
329 | positive SK_ScalarMax. Returns false for any SkPoint array value of |
330 | SK_ScalarInfinity, SK_ScalarNegativeInfinity, or SK_ScalarNaN. |
331 | |
332 | @return true if all SkPoint values are finite |
333 | */ |
334 | bool isFinite() const { |
335 | SkDEBUGCODE(this->validate();) |
336 | return fPathRef->isFinite(); |
337 | } |
338 | |
339 | /** Returns true if the path is volatile; it will not be altered or discarded |
340 | by the caller after it is drawn. SkPath by default have volatile set false, allowing |
341 | SkSurface to attach a cache of data which speeds repeated drawing. If true, SkSurface |
342 | may not speed repeated drawing. |
343 | |
344 | @return true if caller will alter SkPath after drawing |
345 | */ |
346 | bool isVolatile() const { |
347 | return SkToBool(fIsVolatile); |
348 | } |
349 | |
350 | /** Specifies whether SkPath is volatile; whether it will be altered or discarded |
351 | by the caller after it is drawn. SkPath by default have volatile set false, allowing |
352 | SkBaseDevice to attach a cache of data which speeds repeated drawing. |
353 | |
354 | Mark temporary paths, discarded or modified after use, as volatile |
355 | to inform SkBaseDevice that the path need not be cached. |
356 | |
357 | Mark animating SkPath volatile to improve performance. |
358 | Mark unchanging SkPath non-volatile to improve repeated rendering. |
359 | |
360 | raster surface SkPath draws are affected by volatile for some shadows. |
361 | GPU surface SkPath draws are affected by volatile for some shadows and concave geometries. |
362 | |
363 | @param isVolatile true if caller will alter SkPath after drawing |
364 | */ |
365 | void setIsVolatile(bool isVolatile) { |
366 | fIsVolatile = isVolatile; |
367 | } |
368 | |
369 | /** Tests if line between SkPoint pair is degenerate. |
370 | Line with no length or that moves a very short distance is degenerate; it is |
371 | treated as a point. |
372 | |
373 | exact changes the equality test. If true, returns true only if p1 equals p2. |
374 | If false, returns true if p1 equals or nearly equals p2. |
375 | |
376 | @param p1 line start point |
377 | @param p2 line end point |
378 | @param exact if false, allow nearly equals |
379 | @return true if line is degenerate; its length is effectively zero |
380 | |
381 | example: https://fiddle.skia.org/c/@Path_IsLineDegenerate |
382 | */ |
383 | static bool IsLineDegenerate(const SkPoint& p1, const SkPoint& p2, bool exact); |
384 | |
385 | /** Tests if quad is degenerate. |
386 | Quad with no length or that moves a very short distance is degenerate; it is |
387 | treated as a point. |
388 | |
389 | @param p1 quad start point |
390 | @param p2 quad control point |
391 | @param p3 quad end point |
392 | @param exact if true, returns true only if p1, p2, and p3 are equal; |
393 | if false, returns true if p1, p2, and p3 are equal or nearly equal |
394 | @return true if quad is degenerate; its length is effectively zero |
395 | */ |
396 | static bool IsQuadDegenerate(const SkPoint& p1, const SkPoint& p2, |
397 | const SkPoint& p3, bool exact); |
398 | |
399 | /** Tests if cubic is degenerate. |
400 | Cubic with no length or that moves a very short distance is degenerate; it is |
401 | treated as a point. |
402 | |
403 | @param p1 cubic start point |
404 | @param p2 cubic control point 1 |
405 | @param p3 cubic control point 2 |
406 | @param p4 cubic end point |
407 | @param exact if true, returns true only if p1, p2, p3, and p4 are equal; |
408 | if false, returns true if p1, p2, p3, and p4 are equal or nearly equal |
409 | @return true if cubic is degenerate; its length is effectively zero |
410 | */ |
411 | static bool IsCubicDegenerate(const SkPoint& p1, const SkPoint& p2, |
412 | const SkPoint& p3, const SkPoint& p4, bool exact); |
413 | |
414 | /** Returns true if SkPath contains only one line; |
415 | SkPath::Verb array has two entries: kMove_Verb, kLine_Verb. |
416 | If SkPath contains one line and line is not nullptr, line is set to |
417 | line start point and line end point. |
418 | Returns false if SkPath is not one line; line is unaltered. |
419 | |
420 | @param line storage for line. May be nullptr |
421 | @return true if SkPath contains exactly one line |
422 | |
423 | example: https://fiddle.skia.org/c/@Path_isLine |
424 | */ |
425 | bool isLine(SkPoint line[2]) const; |
426 | |
427 | /** Returns the number of points in SkPath. |
428 | SkPoint count is initially zero. |
429 | |
430 | @return SkPath SkPoint array length |
431 | |
432 | example: https://fiddle.skia.org/c/@Path_countPoints |
433 | */ |
434 | int countPoints() const; |
435 | |
436 | /** Returns SkPoint at index in SkPoint array. Valid range for index is |
437 | 0 to countPoints() - 1. |
438 | Returns (0, 0) if index is out of range. |
439 | |
440 | @param index SkPoint array element selector |
441 | @return SkPoint array value or (0, 0) |
442 | |
443 | example: https://fiddle.skia.org/c/@Path_getPoint |
444 | */ |
445 | SkPoint getPoint(int index) const; |
446 | |
447 | /** Returns number of points in SkPath. Up to max points are copied. |
448 | points may be nullptr; then, max must be zero. |
449 | If max is greater than number of points, excess points storage is unaltered. |
450 | |
451 | @param points storage for SkPath SkPoint array. May be nullptr |
452 | @param max maximum to copy; must be greater than or equal to zero |
453 | @return SkPath SkPoint array length |
454 | |
455 | example: https://fiddle.skia.org/c/@Path_getPoints |
456 | */ |
457 | int getPoints(SkPoint points[], int max) const; |
458 | |
459 | /** Returns the number of verbs: kMove_Verb, kLine_Verb, kQuad_Verb, kConic_Verb, |
460 | kCubic_Verb, and kClose_Verb; added to SkPath. |
461 | |
462 | @return length of verb array |
463 | |
464 | example: https://fiddle.skia.org/c/@Path_countVerbs |
465 | */ |
466 | int countVerbs() const; |
467 | |
468 | /** Returns the number of verbs in the path. Up to max verbs are copied. The |
469 | verbs are copied as one byte per verb. |
470 | |
471 | @param verbs storage for verbs, may be nullptr |
472 | @param max maximum number to copy into verbs |
473 | @return the actual number of verbs in the path |
474 | |
475 | example: https://fiddle.skia.org/c/@Path_getVerbs |
476 | */ |
477 | int getVerbs(uint8_t verbs[], int max) const; |
478 | |
479 | /** Returns the approximate byte size of the SkPath in memory. |
480 | |
481 | @return approximate size |
482 | */ |
483 | size_t approximateBytesUsed() const; |
484 | |
485 | /** Exchanges the verb array, SkPoint array, weights, and SkPath::FillType with other. |
486 | Cached state is also exchanged. swap() internally exchanges pointers, so |
487 | it is lightweight and does not allocate memory. |
488 | |
489 | swap() usage has largely been replaced by operator=(const SkPath& path). |
490 | SkPath do not copy their content on assignment until they are written to, |
491 | making assignment as efficient as swap(). |
492 | |
493 | @param other SkPath exchanged by value |
494 | |
495 | example: https://fiddle.skia.org/c/@Path_swap |
496 | */ |
497 | void swap(SkPath& other); |
498 | |
499 | /** Returns minimum and maximum axes values of SkPoint array. |
500 | Returns (0, 0, 0, 0) if SkPath contains no points. Returned bounds width and height may |
501 | be larger or smaller than area affected when SkPath is drawn. |
502 | |
503 | SkRect returned includes all SkPoint added to SkPath, including SkPoint associated with |
504 | kMove_Verb that define empty contours. |
505 | |
506 | @return bounds of all SkPoint in SkPoint array |
507 | */ |
508 | const SkRect& getBounds() const { |
509 | return fPathRef->getBounds(); |
510 | } |
511 | |
512 | /** Updates internal bounds so that subsequent calls to getBounds() are instantaneous. |
513 | Unaltered copies of SkPath may also access cached bounds through getBounds(). |
514 | |
515 | For now, identical to calling getBounds() and ignoring the returned value. |
516 | |
517 | Call to prepare SkPath subsequently drawn from multiple threads, |
518 | to avoid a race condition where each draw separately computes the bounds. |
519 | */ |
520 | void updateBoundsCache() const { |
521 | // for now, just calling getBounds() is sufficient |
522 | this->getBounds(); |
523 | } |
524 | |
525 | /** Returns minimum and maximum axes values of the lines and curves in SkPath. |
526 | Returns (0, 0, 0, 0) if SkPath contains no points. |
527 | Returned bounds width and height may be larger or smaller than area affected |
528 | when SkPath is drawn. |
529 | |
530 | Includes SkPoint associated with kMove_Verb that define empty |
531 | contours. |
532 | |
533 | Behaves identically to getBounds() when SkPath contains |
534 | only lines. If SkPath contains curves, computed bounds includes |
535 | the maximum extent of the quad, conic, or cubic; is slower than getBounds(); |
536 | and unlike getBounds(), does not cache the result. |
537 | |
538 | @return tight bounds of curves in SkPath |
539 | |
540 | example: https://fiddle.skia.org/c/@Path_computeTightBounds |
541 | */ |
542 | SkRect computeTightBounds() const; |
543 | |
544 | /** Returns true if rect is contained by SkPath. |
545 | May return false when rect is contained by SkPath. |
546 | |
547 | For now, only returns true if SkPath has one contour and is convex. |
548 | rect may share points and edges with SkPath and be contained. |
549 | Returns true if rect is empty, that is, it has zero width or height; and |
550 | the SkPoint or line described by rect is contained by SkPath. |
551 | |
552 | @param rect SkRect, line, or SkPoint checked for containment |
553 | @return true if rect is contained |
554 | |
555 | example: https://fiddle.skia.org/c/@Path_conservativelyContainsRect |
556 | */ |
557 | bool conservativelyContainsRect(const SkRect& rect) const; |
558 | |
559 | /** Grows SkPath verb array and SkPoint array to contain extraPtCount additional SkPoint. |
560 | May improve performance and use less memory by |
561 | reducing the number and size of allocations when creating SkPath. |
562 | |
563 | @param extraPtCount number of additional SkPoint to allocate |
564 | |
565 | example: https://fiddle.skia.org/c/@Path_incReserve |
566 | */ |
567 | void incReserve(int ); |
568 | |
569 | /** Shrinks SkPath verb array and SkPoint array storage to discard unused capacity. |
570 | May reduce the heap overhead for SkPath known to be fully constructed. |
571 | */ |
572 | void shrinkToFit(); |
573 | |
574 | #ifdef SK_HIDE_PATH_EDIT_METHODS |
575 | private: |
576 | #endif |
577 | |
578 | /** Adds beginning of contour at SkPoint (x, y). |
579 | |
580 | @param x x-axis value of contour start |
581 | @param y y-axis value of contour start |
582 | @return reference to SkPath |
583 | |
584 | example: https://fiddle.skia.org/c/@Path_moveTo |
585 | */ |
586 | SkPath& moveTo(SkScalar x, SkScalar y); |
587 | |
588 | /** Adds beginning of contour at SkPoint p. |
589 | |
590 | @param p contour start |
591 | @return reference to SkPath |
592 | */ |
593 | SkPath& moveTo(const SkPoint& p) { |
594 | return this->moveTo(p.fX, p.fY); |
595 | } |
596 | |
597 | /** Adds beginning of contour relative to last point. |
598 | If SkPath is empty, starts contour at (dx, dy). |
599 | Otherwise, start contour at last point offset by (dx, dy). |
600 | Function name stands for "relative move to". |
601 | |
602 | @param dx offset from last point to contour start on x-axis |
603 | @param dy offset from last point to contour start on y-axis |
604 | @return reference to SkPath |
605 | |
606 | example: https://fiddle.skia.org/c/@Path_rMoveTo |
607 | */ |
608 | SkPath& rMoveTo(SkScalar dx, SkScalar dy); |
609 | |
610 | /** Adds line from last point to (x, y). If SkPath is empty, or last SkPath::Verb is |
611 | kClose_Verb, last point is set to (0, 0) before adding line. |
612 | |
613 | lineTo() appends kMove_Verb to verb array and (0, 0) to SkPoint array, if needed. |
614 | lineTo() then appends kLine_Verb to verb array and (x, y) to SkPoint array. |
615 | |
616 | @param x end of added line on x-axis |
617 | @param y end of added line on y-axis |
618 | @return reference to SkPath |
619 | |
620 | example: https://fiddle.skia.org/c/@Path_lineTo |
621 | */ |
622 | SkPath& lineTo(SkScalar x, SkScalar y); |
623 | |
624 | /** Adds line from last point to SkPoint p. If SkPath is empty, or last SkPath::Verb is |
625 | kClose_Verb, last point is set to (0, 0) before adding line. |
626 | |
627 | lineTo() first appends kMove_Verb to verb array and (0, 0) to SkPoint array, if needed. |
628 | lineTo() then appends kLine_Verb to verb array and SkPoint p to SkPoint array. |
629 | |
630 | @param p end SkPoint of added line |
631 | @return reference to SkPath |
632 | */ |
633 | SkPath& lineTo(const SkPoint& p) { |
634 | return this->lineTo(p.fX, p.fY); |
635 | } |
636 | |
637 | /** Adds line from last point to vector (dx, dy). If SkPath is empty, or last SkPath::Verb is |
638 | kClose_Verb, last point is set to (0, 0) before adding line. |
639 | |
640 | Appends kMove_Verb to verb array and (0, 0) to SkPoint array, if needed; |
641 | then appends kLine_Verb to verb array and line end to SkPoint array. |
642 | Line end is last point plus vector (dx, dy). |
643 | Function name stands for "relative line to". |
644 | |
645 | @param dx offset from last point to line end on x-axis |
646 | @param dy offset from last point to line end on y-axis |
647 | @return reference to SkPath |
648 | |
649 | example: https://fiddle.skia.org/c/@Path_rLineTo |
650 | example: https://fiddle.skia.org/c/@Quad_a |
651 | example: https://fiddle.skia.org/c/@Quad_b |
652 | */ |
653 | SkPath& rLineTo(SkScalar dx, SkScalar dy); |
654 | |
655 | /** Adds quad from last point towards (x1, y1), to (x2, y2). |
656 | If SkPath is empty, or last SkPath::Verb is kClose_Verb, last point is set to (0, 0) |
657 | before adding quad. |
658 | |
659 | Appends kMove_Verb to verb array and (0, 0) to SkPoint array, if needed; |
660 | then appends kQuad_Verb to verb array; and (x1, y1), (x2, y2) |
661 | to SkPoint array. |
662 | |
663 | @param x1 control SkPoint of quad on x-axis |
664 | @param y1 control SkPoint of quad on y-axis |
665 | @param x2 end SkPoint of quad on x-axis |
666 | @param y2 end SkPoint of quad on y-axis |
667 | @return reference to SkPath |
668 | |
669 | example: https://fiddle.skia.org/c/@Path_quadTo |
670 | */ |
671 | SkPath& quadTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2); |
672 | |
673 | /** Adds quad from last point towards SkPoint p1, to SkPoint p2. |
674 | If SkPath is empty, or last SkPath::Verb is kClose_Verb, last point is set to (0, 0) |
675 | before adding quad. |
676 | |
677 | Appends kMove_Verb to verb array and (0, 0) to SkPoint array, if needed; |
678 | then appends kQuad_Verb to verb array; and SkPoint p1, p2 |
679 | to SkPoint array. |
680 | |
681 | @param p1 control SkPoint of added quad |
682 | @param p2 end SkPoint of added quad |
683 | @return reference to SkPath |
684 | */ |
685 | SkPath& quadTo(const SkPoint& p1, const SkPoint& p2) { |
686 | return this->quadTo(p1.fX, p1.fY, p2.fX, p2.fY); |
687 | } |
688 | |
689 | /** Adds quad from last point towards vector (dx1, dy1), to vector (dx2, dy2). |
690 | If SkPath is empty, or last SkPath::Verb |
691 | is kClose_Verb, last point is set to (0, 0) before adding quad. |
692 | |
693 | Appends kMove_Verb to verb array and (0, 0) to SkPoint array, |
694 | if needed; then appends kQuad_Verb to verb array; and appends quad |
695 | control and quad end to SkPoint array. |
696 | Quad control is last point plus vector (dx1, dy1). |
697 | Quad end is last point plus vector (dx2, dy2). |
698 | Function name stands for "relative quad to". |
699 | |
700 | @param dx1 offset from last point to quad control on x-axis |
701 | @param dy1 offset from last point to quad control on y-axis |
702 | @param dx2 offset from last point to quad end on x-axis |
703 | @param dy2 offset from last point to quad end on y-axis |
704 | @return reference to SkPath |
705 | |
706 | example: https://fiddle.skia.org/c/@Conic_Weight_a |
707 | example: https://fiddle.skia.org/c/@Conic_Weight_b |
708 | example: https://fiddle.skia.org/c/@Conic_Weight_c |
709 | example: https://fiddle.skia.org/c/@Path_rQuadTo |
710 | */ |
711 | SkPath& rQuadTo(SkScalar dx1, SkScalar dy1, SkScalar dx2, SkScalar dy2); |
712 | |
713 | /** Adds conic from last point towards (x1, y1), to (x2, y2), weighted by w. |
714 | If SkPath is empty, or last SkPath::Verb is kClose_Verb, last point is set to (0, 0) |
715 | before adding conic. |
716 | |
717 | Appends kMove_Verb to verb array and (0, 0) to SkPoint array, if needed. |
718 | |
719 | If w is finite and not one, appends kConic_Verb to verb array; |
720 | and (x1, y1), (x2, y2) to SkPoint array; and w to conic weights. |
721 | |
722 | If w is one, appends kQuad_Verb to verb array, and |
723 | (x1, y1), (x2, y2) to SkPoint array. |
724 | |
725 | If w is not finite, appends kLine_Verb twice to verb array, and |
726 | (x1, y1), (x2, y2) to SkPoint array. |
727 | |
728 | @param x1 control SkPoint of conic on x-axis |
729 | @param y1 control SkPoint of conic on y-axis |
730 | @param x2 end SkPoint of conic on x-axis |
731 | @param y2 end SkPoint of conic on y-axis |
732 | @param w weight of added conic |
733 | @return reference to SkPath |
734 | */ |
735 | SkPath& conicTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, |
736 | SkScalar w); |
737 | |
738 | /** Adds conic from last point towards SkPoint p1, to SkPoint p2, weighted by w. |
739 | If SkPath is empty, or last SkPath::Verb is kClose_Verb, last point is set to (0, 0) |
740 | before adding conic. |
741 | |
742 | Appends kMove_Verb to verb array and (0, 0) to SkPoint array, if needed. |
743 | |
744 | If w is finite and not one, appends kConic_Verb to verb array; |
745 | and SkPoint p1, p2 to SkPoint array; and w to conic weights. |
746 | |
747 | If w is one, appends kQuad_Verb to verb array, and SkPoint p1, p2 |
748 | to SkPoint array. |
749 | |
750 | If w is not finite, appends kLine_Verb twice to verb array, and |
751 | SkPoint p1, p2 to SkPoint array. |
752 | |
753 | @param p1 control SkPoint of added conic |
754 | @param p2 end SkPoint of added conic |
755 | @param w weight of added conic |
756 | @return reference to SkPath |
757 | */ |
758 | SkPath& conicTo(const SkPoint& p1, const SkPoint& p2, SkScalar w) { |
759 | return this->conicTo(p1.fX, p1.fY, p2.fX, p2.fY, w); |
760 | } |
761 | |
762 | /** Adds conic from last point towards vector (dx1, dy1), to vector (dx2, dy2), |
763 | weighted by w. If SkPath is empty, or last SkPath::Verb |
764 | is kClose_Verb, last point is set to (0, 0) before adding conic. |
765 | |
766 | Appends kMove_Verb to verb array and (0, 0) to SkPoint array, |
767 | if needed. |
768 | |
769 | If w is finite and not one, next appends kConic_Verb to verb array, |
770 | and w is recorded as conic weight; otherwise, if w is one, appends |
771 | kQuad_Verb to verb array; or if w is not finite, appends kLine_Verb |
772 | twice to verb array. |
773 | |
774 | In all cases appends SkPoint control and end to SkPoint array. |
775 | control is last point plus vector (dx1, dy1). |
776 | end is last point plus vector (dx2, dy2). |
777 | |
778 | Function name stands for "relative conic to". |
779 | |
780 | @param dx1 offset from last point to conic control on x-axis |
781 | @param dy1 offset from last point to conic control on y-axis |
782 | @param dx2 offset from last point to conic end on x-axis |
783 | @param dy2 offset from last point to conic end on y-axis |
784 | @param w weight of added conic |
785 | @return reference to SkPath |
786 | */ |
787 | SkPath& rConicTo(SkScalar dx1, SkScalar dy1, SkScalar dx2, SkScalar dy2, |
788 | SkScalar w); |
789 | |
790 | /** Adds cubic from last point towards (x1, y1), then towards (x2, y2), ending at |
791 | (x3, y3). If SkPath is empty, or last SkPath::Verb is kClose_Verb, last point is set to |
792 | (0, 0) before adding cubic. |
793 | |
794 | Appends kMove_Verb to verb array and (0, 0) to SkPoint array, if needed; |
795 | then appends kCubic_Verb to verb array; and (x1, y1), (x2, y2), (x3, y3) |
796 | to SkPoint array. |
797 | |
798 | @param x1 first control SkPoint of cubic on x-axis |
799 | @param y1 first control SkPoint of cubic on y-axis |
800 | @param x2 second control SkPoint of cubic on x-axis |
801 | @param y2 second control SkPoint of cubic on y-axis |
802 | @param x3 end SkPoint of cubic on x-axis |
803 | @param y3 end SkPoint of cubic on y-axis |
804 | @return reference to SkPath |
805 | */ |
806 | SkPath& cubicTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, |
807 | SkScalar x3, SkScalar y3); |
808 | |
809 | /** Adds cubic from last point towards SkPoint p1, then towards SkPoint p2, ending at |
810 | SkPoint p3. If SkPath is empty, or last SkPath::Verb is kClose_Verb, last point is set to |
811 | (0, 0) before adding cubic. |
812 | |
813 | Appends kMove_Verb to verb array and (0, 0) to SkPoint array, if needed; |
814 | then appends kCubic_Verb to verb array; and SkPoint p1, p2, p3 |
815 | to SkPoint array. |
816 | |
817 | @param p1 first control SkPoint of cubic |
818 | @param p2 second control SkPoint of cubic |
819 | @param p3 end SkPoint of cubic |
820 | @return reference to SkPath |
821 | */ |
822 | SkPath& cubicTo(const SkPoint& p1, const SkPoint& p2, const SkPoint& p3) { |
823 | return this->cubicTo(p1.fX, p1.fY, p2.fX, p2.fY, p3.fX, p3.fY); |
824 | } |
825 | |
826 | /** Adds cubic from last point towards vector (dx1, dy1), then towards |
827 | vector (dx2, dy2), to vector (dx3, dy3). |
828 | If SkPath is empty, or last SkPath::Verb |
829 | is kClose_Verb, last point is set to (0, 0) before adding cubic. |
830 | |
831 | Appends kMove_Verb to verb array and (0, 0) to SkPoint array, |
832 | if needed; then appends kCubic_Verb to verb array; and appends cubic |
833 | control and cubic end to SkPoint array. |
834 | Cubic control is last point plus vector (dx1, dy1). |
835 | Cubic end is last point plus vector (dx2, dy2). |
836 | Function name stands for "relative cubic to". |
837 | |
838 | @param dx1 offset from last point to first cubic control on x-axis |
839 | @param dy1 offset from last point to first cubic control on y-axis |
840 | @param dx2 offset from last point to second cubic control on x-axis |
841 | @param dy2 offset from last point to second cubic control on y-axis |
842 | @param dx3 offset from last point to cubic end on x-axis |
843 | @param dy3 offset from last point to cubic end on y-axis |
844 | @return reference to SkPath |
845 | */ |
846 | SkPath& rCubicTo(SkScalar dx1, SkScalar dy1, SkScalar dx2, SkScalar dy2, |
847 | SkScalar dx3, SkScalar dy3); |
848 | |
849 | /** Appends arc to SkPath. Arc added is part of ellipse |
850 | bounded by oval, from startAngle through sweepAngle. Both startAngle and |
851 | sweepAngle are measured in degrees, where zero degrees is aligned with the |
852 | positive x-axis, and positive sweeps extends arc clockwise. |
853 | |
854 | arcTo() adds line connecting SkPath last SkPoint to initial arc SkPoint if forceMoveTo |
855 | is false and SkPath is not empty. Otherwise, added contour begins with first point |
856 | of arc. Angles greater than -360 and less than 360 are treated modulo 360. |
857 | |
858 | @param oval bounds of ellipse containing arc |
859 | @param startAngle starting angle of arc in degrees |
860 | @param sweepAngle sweep, in degrees. Positive is clockwise; treated modulo 360 |
861 | @param forceMoveTo true to start a new contour with arc |
862 | @return reference to SkPath |
863 | |
864 | example: https://fiddle.skia.org/c/@Path_arcTo |
865 | */ |
866 | SkPath& arcTo(const SkRect& oval, SkScalar startAngle, SkScalar sweepAngle, bool forceMoveTo); |
867 | |
868 | /** Appends arc to SkPath, after appending line if needed. Arc is implemented by conic |
869 | weighted to describe part of circle. Arc is contained by tangent from |
870 | last SkPath point to (x1, y1), and tangent from (x1, y1) to (x2, y2). Arc |
871 | is part of circle sized to radius, positioned so it touches both tangent lines. |
872 | |
873 | If last Path Point does not start Arc, arcTo appends connecting Line to Path. |
874 | The length of Vector from (x1, y1) to (x2, y2) does not affect Arc. |
875 | |
876 | Arc sweep is always less than 180 degrees. If radius is zero, or if |
877 | tangents are nearly parallel, arcTo appends Line from last Path Point to (x1, y1). |
878 | |
879 | arcTo appends at most one Line and one conic. |
880 | arcTo implements the functionality of PostScript arct and HTML Canvas arcTo. |
881 | |
882 | @param x1 x-axis value common to pair of tangents |
883 | @param y1 y-axis value common to pair of tangents |
884 | @param x2 x-axis value end of second tangent |
885 | @param y2 y-axis value end of second tangent |
886 | @param radius distance from arc to circle center |
887 | @return reference to SkPath |
888 | |
889 | example: https://fiddle.skia.org/c/@Path_arcTo_2_a |
890 | example: https://fiddle.skia.org/c/@Path_arcTo_2_b |
891 | example: https://fiddle.skia.org/c/@Path_arcTo_2_c |
892 | */ |
893 | SkPath& arcTo(SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2, SkScalar radius); |
894 | |
895 | /** Appends arc to SkPath, after appending line if needed. Arc is implemented by conic |
896 | weighted to describe part of circle. Arc is contained by tangent from |
897 | last SkPath point to p1, and tangent from p1 to p2. Arc |
898 | is part of circle sized to radius, positioned so it touches both tangent lines. |
899 | |
900 | If last SkPath SkPoint does not start arc, arcTo() appends connecting line to SkPath. |
901 | The length of vector from p1 to p2 does not affect arc. |
902 | |
903 | Arc sweep is always less than 180 degrees. If radius is zero, or if |
904 | tangents are nearly parallel, arcTo() appends line from last SkPath SkPoint to p1. |
905 | |
906 | arcTo() appends at most one line and one conic. |
907 | arcTo() implements the functionality of PostScript arct and HTML Canvas arcTo. |
908 | |
909 | @param p1 SkPoint common to pair of tangents |
910 | @param p2 end of second tangent |
911 | @param radius distance from arc to circle center |
912 | @return reference to SkPath |
913 | */ |
914 | SkPath& arcTo(const SkPoint p1, const SkPoint p2, SkScalar radius) { |
915 | return this->arcTo(p1.fX, p1.fY, p2.fX, p2.fY, radius); |
916 | } |
917 | |
918 | /** \enum SkPath::ArcSize |
919 | Four oval parts with radii (rx, ry) start at last SkPath SkPoint and ends at (x, y). |
920 | ArcSize and Direction select one of the four oval parts. |
921 | */ |
922 | enum ArcSize { |
923 | kSmall_ArcSize, //!< smaller of arc pair |
924 | kLarge_ArcSize, //!< larger of arc pair |
925 | }; |
926 | |
927 | /** Appends arc to SkPath. Arc is implemented by one or more conics weighted to |
928 | describe part of oval with radii (rx, ry) rotated by xAxisRotate degrees. Arc |
929 | curves from last SkPath SkPoint to (x, y), choosing one of four possible routes: |
930 | clockwise or counterclockwise, and smaller or larger. |
931 | |
932 | Arc sweep is always less than 360 degrees. arcTo() appends line to (x, y) if |
933 | either radii are zero, or if last SkPath SkPoint equals (x, y). arcTo() scales radii |
934 | (rx, ry) to fit last SkPath SkPoint and (x, y) if both are greater than zero but |
935 | too small. |
936 | |
937 | arcTo() appends up to four conic curves. |
938 | arcTo() implements the functionality of SVG arc, although SVG sweep-flag value |
939 | is opposite the integer value of sweep; SVG sweep-flag uses 1 for clockwise, |
940 | while kCW_Direction cast to int is zero. |
941 | |
942 | @param rx radius on x-axis before x-axis rotation |
943 | @param ry radius on y-axis before x-axis rotation |
944 | @param xAxisRotate x-axis rotation in degrees; positive values are clockwise |
945 | @param largeArc chooses smaller or larger arc |
946 | @param sweep chooses clockwise or counterclockwise arc |
947 | @param x end of arc |
948 | @param y end of arc |
949 | @return reference to SkPath |
950 | */ |
951 | SkPath& arcTo(SkScalar rx, SkScalar ry, SkScalar xAxisRotate, ArcSize largeArc, |
952 | SkPathDirection sweep, SkScalar x, SkScalar y); |
953 | |
954 | /** Appends arc to SkPath. Arc is implemented by one or more conic weighted to describe |
955 | part of oval with radii (r.fX, r.fY) rotated by xAxisRotate degrees. Arc curves |
956 | from last SkPath SkPoint to (xy.fX, xy.fY), choosing one of four possible routes: |
957 | clockwise or counterclockwise, |
958 | and smaller or larger. |
959 | |
960 | Arc sweep is always less than 360 degrees. arcTo() appends line to xy if either |
961 | radii are zero, or if last SkPath SkPoint equals (xy.fX, xy.fY). arcTo() scales radii r to |
962 | fit last SkPath SkPoint and xy if both are greater than zero but too small to describe |
963 | an arc. |
964 | |
965 | arcTo() appends up to four conic curves. |
966 | arcTo() implements the functionality of SVG arc, although SVG sweep-flag value is |
967 | opposite the integer value of sweep; SVG sweep-flag uses 1 for clockwise, while |
968 | kCW_Direction cast to int is zero. |
969 | |
970 | @param r radii on axes before x-axis rotation |
971 | @param xAxisRotate x-axis rotation in degrees; positive values are clockwise |
972 | @param largeArc chooses smaller or larger arc |
973 | @param sweep chooses clockwise or counterclockwise arc |
974 | @param xy end of arc |
975 | @return reference to SkPath |
976 | */ |
977 | SkPath& arcTo(const SkPoint r, SkScalar xAxisRotate, ArcSize largeArc, SkPathDirection sweep, |
978 | const SkPoint xy) { |
979 | return this->arcTo(r.fX, r.fY, xAxisRotate, largeArc, sweep, xy.fX, xy.fY); |
980 | } |
981 | |
982 | /** Appends arc to SkPath, relative to last SkPath SkPoint. Arc is implemented by one or |
983 | more conic, weighted to describe part of oval with radii (rx, ry) rotated by |
984 | xAxisRotate degrees. Arc curves from last SkPath SkPoint to relative end SkPoint: |
985 | (dx, dy), choosing one of four possible routes: clockwise or |
986 | counterclockwise, and smaller or larger. If SkPath is empty, the start arc SkPoint |
987 | is (0, 0). |
988 | |
989 | Arc sweep is always less than 360 degrees. arcTo() appends line to end SkPoint |
990 | if either radii are zero, or if last SkPath SkPoint equals end SkPoint. |
991 | arcTo() scales radii (rx, ry) to fit last SkPath SkPoint and end SkPoint if both are |
992 | greater than zero but too small to describe an arc. |
993 | |
994 | arcTo() appends up to four conic curves. |
995 | arcTo() implements the functionality of svg arc, although SVG "sweep-flag" value is |
996 | opposite the integer value of sweep; SVG "sweep-flag" uses 1 for clockwise, while |
997 | kCW_Direction cast to int is zero. |
998 | |
999 | @param rx radius before x-axis rotation |
1000 | @param ry radius before x-axis rotation |
1001 | @param xAxisRotate x-axis rotation in degrees; positive values are clockwise |
1002 | @param largeArc chooses smaller or larger arc |
1003 | @param sweep chooses clockwise or counterclockwise arc |
1004 | @param dx x-axis offset end of arc from last SkPath SkPoint |
1005 | @param dy y-axis offset end of arc from last SkPath SkPoint |
1006 | @return reference to SkPath |
1007 | */ |
1008 | SkPath& rArcTo(SkScalar rx, SkScalar ry, SkScalar xAxisRotate, ArcSize largeArc, |
1009 | SkPathDirection sweep, SkScalar dx, SkScalar dy); |
1010 | |
1011 | /** Appends kClose_Verb to SkPath. A closed contour connects the first and last SkPoint |
1012 | with line, forming a continuous loop. Open and closed contour draw the same |
1013 | with SkPaint::kFill_Style. With SkPaint::kStroke_Style, open contour draws |
1014 | SkPaint::Cap at contour start and end; closed contour draws |
1015 | SkPaint::Join at contour start and end. |
1016 | |
1017 | close() has no effect if SkPath is empty or last SkPath SkPath::Verb is kClose_Verb. |
1018 | |
1019 | @return reference to SkPath |
1020 | |
1021 | example: https://fiddle.skia.org/c/@Path_close |
1022 | */ |
1023 | SkPath& close(); |
1024 | |
1025 | #ifdef SK_HIDE_PATH_EDIT_METHODS |
1026 | public: |
1027 | #endif |
1028 | |
1029 | /** Approximates conic with quad array. Conic is constructed from start SkPoint p0, |
1030 | control SkPoint p1, end SkPoint p2, and weight w. |
1031 | Quad array is stored in pts; this storage is supplied by caller. |
1032 | Maximum quad count is 2 to the pow2. |
1033 | Every third point in array shares last SkPoint of previous quad and first SkPoint of |
1034 | next quad. Maximum pts storage size is given by: |
1035 | (1 + 2 * (1 << pow2)) * sizeof(SkPoint). |
1036 | |
1037 | Returns quad count used the approximation, which may be smaller |
1038 | than the number requested. |
1039 | |
1040 | conic weight determines the amount of influence conic control point has on the curve. |
1041 | w less than one represents an elliptical section. w greater than one represents |
1042 | a hyperbolic section. w equal to one represents a parabolic section. |
1043 | |
1044 | Two quad curves are sufficient to approximate an elliptical conic with a sweep |
1045 | of up to 90 degrees; in this case, set pow2 to one. |
1046 | |
1047 | @param p0 conic start SkPoint |
1048 | @param p1 conic control SkPoint |
1049 | @param p2 conic end SkPoint |
1050 | @param w conic weight |
1051 | @param pts storage for quad array |
1052 | @param pow2 quad count, as power of two, normally 0 to 5 (1 to 32 quad curves) |
1053 | @return number of quad curves written to pts |
1054 | */ |
1055 | static int ConvertConicToQuads(const SkPoint& p0, const SkPoint& p1, const SkPoint& p2, |
1056 | SkScalar w, SkPoint pts[], int pow2); |
1057 | |
1058 | /** Returns true if SkPath is equivalent to SkRect when filled. |
1059 | If false: rect, isClosed, and direction are unchanged. |
1060 | If true: rect, isClosed, and direction are written to if not nullptr. |
1061 | |
1062 | rect may be smaller than the SkPath bounds. SkPath bounds may include kMove_Verb points |
1063 | that do not alter the area drawn by the returned rect. |
1064 | |
1065 | @param rect storage for bounds of SkRect; may be nullptr |
1066 | @param isClosed storage set to true if SkPath is closed; may be nullptr |
1067 | @param direction storage set to SkRect direction; may be nullptr |
1068 | @return true if SkPath contains SkRect |
1069 | |
1070 | example: https://fiddle.skia.org/c/@Path_isRect |
1071 | */ |
1072 | bool isRect(SkRect* rect, bool* isClosed = nullptr, SkPathDirection* direction = nullptr) const; |
1073 | |
1074 | /** Adds SkRect to SkPath, appending kMove_Verb, three kLine_Verb, and kClose_Verb, |
1075 | starting with top-left corner of SkRect; followed by top-right, bottom-right, |
1076 | and bottom-left if dir is kCW_Direction; or followed by bottom-left, |
1077 | bottom-right, and top-right if dir is kCCW_Direction. |
1078 | |
1079 | @param rect SkRect to add as a closed contour |
1080 | @param dir SkPath::Direction to wind added contour |
1081 | @return reference to SkPath |
1082 | |
1083 | example: https://fiddle.skia.org/c/@Path_addRect |
1084 | */ |
1085 | SkPath& addRect(const SkRect& rect, SkPathDirection dir = SkPathDirection::kCW); |
1086 | |
1087 | /** Adds SkRect to SkPath, appending kMove_Verb, three kLine_Verb, and kClose_Verb. |
1088 | If dir is kCW_Direction, SkRect corners are added clockwise; if dir is |
1089 | kCCW_Direction, SkRect corners are added counterclockwise. |
1090 | start determines the first corner added. |
1091 | |
1092 | @param rect SkRect to add as a closed contour |
1093 | @param dir SkPath::Direction to wind added contour |
1094 | @param start initial corner of SkRect to add |
1095 | @return reference to SkPath |
1096 | |
1097 | example: https://fiddle.skia.org/c/@Path_addRect_2 |
1098 | */ |
1099 | SkPath& addRect(const SkRect& rect, SkPathDirection dir, unsigned start); |
1100 | |
1101 | /** Adds SkRect (left, top, right, bottom) to SkPath, |
1102 | appending kMove_Verb, three kLine_Verb, and kClose_Verb, |
1103 | starting with top-left corner of SkRect; followed by top-right, bottom-right, |
1104 | and bottom-left if dir is kCW_Direction; or followed by bottom-left, |
1105 | bottom-right, and top-right if dir is kCCW_Direction. |
1106 | |
1107 | @param left smaller x-axis value of SkRect |
1108 | @param top smaller y-axis value of SkRect |
1109 | @param right larger x-axis value of SkRect |
1110 | @param bottom larger y-axis value of SkRect |
1111 | @param dir SkPath::Direction to wind added contour |
1112 | @return reference to SkPath |
1113 | */ |
1114 | SkPath& addRect(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom, |
1115 | SkPathDirection dir = SkPathDirection::kCW); |
1116 | |
1117 | /** Adds oval to path, appending kMove_Verb, four kConic_Verb, and kClose_Verb. |
1118 | Oval is upright ellipse bounded by SkRect oval with radii equal to half oval width |
1119 | and half oval height. Oval begins at (oval.fRight, oval.centerY()) and continues |
1120 | clockwise if dir is kCW_Direction, counterclockwise if dir is kCCW_Direction. |
1121 | |
1122 | @param oval bounds of ellipse added |
1123 | @param dir SkPath::Direction to wind ellipse |
1124 | @return reference to SkPath |
1125 | |
1126 | example: https://fiddle.skia.org/c/@Path_addOval |
1127 | */ |
1128 | SkPath& addOval(const SkRect& oval, SkPathDirection dir = SkPathDirection::kCW); |
1129 | |
1130 | /** Adds oval to SkPath, appending kMove_Verb, four kConic_Verb, and kClose_Verb. |
1131 | Oval is upright ellipse bounded by SkRect oval with radii equal to half oval width |
1132 | and half oval height. Oval begins at start and continues |
1133 | clockwise if dir is kCW_Direction, counterclockwise if dir is kCCW_Direction. |
1134 | |
1135 | @param oval bounds of ellipse added |
1136 | @param dir SkPath::Direction to wind ellipse |
1137 | @param start index of initial point of ellipse |
1138 | @return reference to SkPath |
1139 | |
1140 | example: https://fiddle.skia.org/c/@Path_addOval_2 |
1141 | */ |
1142 | SkPath& addOval(const SkRect& oval, SkPathDirection dir, unsigned start); |
1143 | |
1144 | /** Adds circle centered at (x, y) of size radius to SkPath, appending kMove_Verb, |
1145 | four kConic_Verb, and kClose_Verb. Circle begins at: (x + radius, y), continuing |
1146 | clockwise if dir is kCW_Direction, and counterclockwise if dir is kCCW_Direction. |
1147 | |
1148 | Has no effect if radius is zero or negative. |
1149 | |
1150 | @param x center of circle |
1151 | @param y center of circle |
1152 | @param radius distance from center to edge |
1153 | @param dir SkPath::Direction to wind circle |
1154 | @return reference to SkPath |
1155 | */ |
1156 | SkPath& addCircle(SkScalar x, SkScalar y, SkScalar radius, |
1157 | SkPathDirection dir = SkPathDirection::kCW); |
1158 | |
1159 | /** Appends arc to SkPath, as the start of new contour. Arc added is part of ellipse |
1160 | bounded by oval, from startAngle through sweepAngle. Both startAngle and |
1161 | sweepAngle are measured in degrees, where zero degrees is aligned with the |
1162 | positive x-axis, and positive sweeps extends arc clockwise. |
1163 | |
1164 | If sweepAngle <= -360, or sweepAngle >= 360; and startAngle modulo 90 is nearly |
1165 | zero, append oval instead of arc. Otherwise, sweepAngle values are treated |
1166 | modulo 360, and arc may or may not draw depending on numeric rounding. |
1167 | |
1168 | @param oval bounds of ellipse containing arc |
1169 | @param startAngle starting angle of arc in degrees |
1170 | @param sweepAngle sweep, in degrees. Positive is clockwise; treated modulo 360 |
1171 | @return reference to SkPath |
1172 | |
1173 | example: https://fiddle.skia.org/c/@Path_addArc |
1174 | */ |
1175 | SkPath& addArc(const SkRect& oval, SkScalar startAngle, SkScalar sweepAngle); |
1176 | |
1177 | /** Appends SkRRect to SkPath, creating a new closed contour. SkRRect has bounds |
1178 | equal to rect; each corner is 90 degrees of an ellipse with radii (rx, ry). If |
1179 | dir is kCW_Direction, SkRRect starts at top-left of the lower-left corner and |
1180 | winds clockwise. If dir is kCCW_Direction, SkRRect starts at the bottom-left |
1181 | of the upper-left corner and winds counterclockwise. |
1182 | |
1183 | If either rx or ry is too large, rx and ry are scaled uniformly until the |
1184 | corners fit. If rx or ry is less than or equal to zero, addRoundRect() appends |
1185 | SkRect rect to SkPath. |
1186 | |
1187 | After appending, SkPath may be empty, or may contain: SkRect, oval, or SkRRect. |
1188 | |
1189 | @param rect bounds of SkRRect |
1190 | @param rx x-axis radius of rounded corners on the SkRRect |
1191 | @param ry y-axis radius of rounded corners on the SkRRect |
1192 | @param dir SkPath::Direction to wind SkRRect |
1193 | @return reference to SkPath |
1194 | */ |
1195 | SkPath& addRoundRect(const SkRect& rect, SkScalar rx, SkScalar ry, |
1196 | SkPathDirection dir = SkPathDirection::kCW); |
1197 | |
1198 | /** Appends SkRRect to SkPath, creating a new closed contour. SkRRect has bounds |
1199 | equal to rect; each corner is 90 degrees of an ellipse with radii from the |
1200 | array. |
1201 | |
1202 | @param rect bounds of SkRRect |
1203 | @param radii array of 8 SkScalar values, a radius pair for each corner |
1204 | @param dir SkPath::Direction to wind SkRRect |
1205 | @return reference to SkPath |
1206 | */ |
1207 | SkPath& addRoundRect(const SkRect& rect, const SkScalar radii[], |
1208 | SkPathDirection dir = SkPathDirection::kCW); |
1209 | |
1210 | /** Adds rrect to SkPath, creating a new closed contour. If |
1211 | dir is kCW_Direction, rrect starts at top-left of the lower-left corner and |
1212 | winds clockwise. If dir is kCCW_Direction, rrect starts at the bottom-left |
1213 | of the upper-left corner and winds counterclockwise. |
1214 | |
1215 | After appending, SkPath may be empty, or may contain: SkRect, oval, or SkRRect. |
1216 | |
1217 | @param rrect bounds and radii of rounded rectangle |
1218 | @param dir SkPath::Direction to wind SkRRect |
1219 | @return reference to SkPath |
1220 | |
1221 | example: https://fiddle.skia.org/c/@Path_addRRect |
1222 | */ |
1223 | SkPath& addRRect(const SkRRect& rrect, SkPathDirection dir = SkPathDirection::kCW); |
1224 | |
1225 | /** Adds rrect to SkPath, creating a new closed contour. If dir is kCW_Direction, rrect |
1226 | winds clockwise; if dir is kCCW_Direction, rrect winds counterclockwise. |
1227 | start determines the first point of rrect to add. |
1228 | |
1229 | @param rrect bounds and radii of rounded rectangle |
1230 | @param dir SkPath::Direction to wind SkRRect |
1231 | @param start index of initial point of SkRRect |
1232 | @return reference to SkPath |
1233 | |
1234 | example: https://fiddle.skia.org/c/@Path_addRRect_2 |
1235 | */ |
1236 | SkPath& addRRect(const SkRRect& rrect, SkPathDirection dir, unsigned start); |
1237 | |
1238 | /** Adds contour created from line array, adding (count - 1) line segments. |
1239 | Contour added starts at pts[0], then adds a line for every additional SkPoint |
1240 | in pts array. If close is true, appends kClose_Verb to SkPath, connecting |
1241 | pts[count - 1] and pts[0]. |
1242 | |
1243 | If count is zero, append kMove_Verb to path. |
1244 | Has no effect if count is less than one. |
1245 | |
1246 | @param pts array of line sharing end and start SkPoint |
1247 | @param count length of SkPoint array |
1248 | @param close true to add line connecting contour end and start |
1249 | @return reference to SkPath |
1250 | |
1251 | example: https://fiddle.skia.org/c/@Path_addPoly |
1252 | */ |
1253 | SkPath& addPoly(const SkPoint pts[], int count, bool close); |
1254 | |
1255 | /** Adds contour created from list. Contour added starts at list[0], then adds a line |
1256 | for every additional SkPoint in list. If close is true, appends kClose_Verb to SkPath, |
1257 | connecting last and first SkPoint in list. |
1258 | |
1259 | If list is empty, append kMove_Verb to path. |
1260 | |
1261 | @param list array of SkPoint |
1262 | @param close true to add line connecting contour end and start |
1263 | @return reference to SkPath |
1264 | */ |
1265 | SkPath& addPoly(const std::initializer_list<SkPoint>& list, bool close) { |
1266 | return this->addPoly(list.begin(), SkToInt(list.size()), close); |
1267 | } |
1268 | |
1269 | /** \enum SkPath::AddPathMode |
1270 | AddPathMode chooses how addPath() appends. Adding one SkPath to another can extend |
1271 | the last contour or start a new contour. |
1272 | */ |
1273 | enum AddPathMode { |
1274 | kAppend_AddPathMode, //!< appended to destination unaltered |
1275 | kExtend_AddPathMode, //!< add line if prior contour is not closed |
1276 | }; |
1277 | |
1278 | /** Appends src to SkPath, offset by (dx, dy). |
1279 | |
1280 | If mode is kAppend_AddPathMode, src verb array, SkPoint array, and conic weights are |
1281 | added unaltered. If mode is kExtend_AddPathMode, add line before appending |
1282 | verbs, SkPoint, and conic weights. |
1283 | |
1284 | @param src SkPath verbs, SkPoint, and conic weights to add |
1285 | @param dx offset added to src SkPoint array x-axis coordinates |
1286 | @param dy offset added to src SkPoint array y-axis coordinates |
1287 | @param mode kAppend_AddPathMode or kExtend_AddPathMode |
1288 | @return reference to SkPath |
1289 | */ |
1290 | SkPath& addPath(const SkPath& src, SkScalar dx, SkScalar dy, |
1291 | AddPathMode mode = kAppend_AddPathMode); |
1292 | |
1293 | /** Appends src to SkPath. |
1294 | |
1295 | If mode is kAppend_AddPathMode, src verb array, SkPoint array, and conic weights are |
1296 | added unaltered. If mode is kExtend_AddPathMode, add line before appending |
1297 | verbs, SkPoint, and conic weights. |
1298 | |
1299 | @param src SkPath verbs, SkPoint, and conic weights to add |
1300 | @param mode kAppend_AddPathMode or kExtend_AddPathMode |
1301 | @return reference to SkPath |
1302 | */ |
1303 | SkPath& addPath(const SkPath& src, AddPathMode mode = kAppend_AddPathMode) { |
1304 | SkMatrix m; |
1305 | m.reset(); |
1306 | return this->addPath(src, m, mode); |
1307 | } |
1308 | |
1309 | /** Appends src to SkPath, transformed by matrix. Transformed curves may have different |
1310 | verbs, SkPoint, and conic weights. |
1311 | |
1312 | If mode is kAppend_AddPathMode, src verb array, SkPoint array, and conic weights are |
1313 | added unaltered. If mode is kExtend_AddPathMode, add line before appending |
1314 | verbs, SkPoint, and conic weights. |
1315 | |
1316 | @param src SkPath verbs, SkPoint, and conic weights to add |
1317 | @param matrix transform applied to src |
1318 | @param mode kAppend_AddPathMode or kExtend_AddPathMode |
1319 | @return reference to SkPath |
1320 | */ |
1321 | SkPath& addPath(const SkPath& src, const SkMatrix& matrix, |
1322 | AddPathMode mode = kAppend_AddPathMode); |
1323 | |
1324 | /** Appends src to SkPath, from back to front. |
1325 | Reversed src always appends a new contour to SkPath. |
1326 | |
1327 | @param src SkPath verbs, SkPoint, and conic weights to add |
1328 | @return reference to SkPath |
1329 | |
1330 | example: https://fiddle.skia.org/c/@Path_reverseAddPath |
1331 | */ |
1332 | SkPath& reverseAddPath(const SkPath& src); |
1333 | |
1334 | /** Offsets SkPoint array by (dx, dy). Offset SkPath replaces dst. |
1335 | If dst is nullptr, SkPath is replaced by offset data. |
1336 | |
1337 | @param dx offset added to SkPoint array x-axis coordinates |
1338 | @param dy offset added to SkPoint array y-axis coordinates |
1339 | @param dst overwritten, translated copy of SkPath; may be nullptr |
1340 | |
1341 | example: https://fiddle.skia.org/c/@Path_offset |
1342 | */ |
1343 | void offset(SkScalar dx, SkScalar dy, SkPath* dst) const; |
1344 | |
1345 | /** Offsets SkPoint array by (dx, dy). SkPath is replaced by offset data. |
1346 | |
1347 | @param dx offset added to SkPoint array x-axis coordinates |
1348 | @param dy offset added to SkPoint array y-axis coordinates |
1349 | */ |
1350 | void offset(SkScalar dx, SkScalar dy) { |
1351 | this->offset(dx, dy, this); |
1352 | } |
1353 | |
1354 | /** Transforms verb array, SkPoint array, and weight by matrix. |
1355 | transform may change verbs and increase their number. |
1356 | Transformed SkPath replaces dst; if dst is nullptr, original data |
1357 | is replaced. |
1358 | |
1359 | @param matrix SkMatrix to apply to SkPath |
1360 | @param dst overwritten, transformed copy of SkPath; may be nullptr |
1361 | @param pc whether to apply perspective clipping |
1362 | |
1363 | example: https://fiddle.skia.org/c/@Path_transform |
1364 | */ |
1365 | void transform(const SkMatrix& matrix, SkPath* dst, |
1366 | SkApplyPerspectiveClip pc = SkApplyPerspectiveClip::kYes) const; |
1367 | |
1368 | /** Transforms verb array, SkPoint array, and weight by matrix. |
1369 | transform may change verbs and increase their number. |
1370 | SkPath is replaced by transformed data. |
1371 | |
1372 | @param matrix SkMatrix to apply to SkPath |
1373 | @param pc whether to apply perspective clipping |
1374 | */ |
1375 | void transform(const SkMatrix& matrix, |
1376 | SkApplyPerspectiveClip pc = SkApplyPerspectiveClip::kYes) { |
1377 | this->transform(matrix, this, pc); |
1378 | } |
1379 | |
1380 | SkPath makeTransform(const SkMatrix& m, |
1381 | SkApplyPerspectiveClip pc = SkApplyPerspectiveClip::kYes) const { |
1382 | SkPath dst; |
1383 | this->transform(m, &dst, pc); |
1384 | return dst; |
1385 | } |
1386 | |
1387 | SkPath makeScale(SkScalar sx, SkScalar sy) { |
1388 | return this->makeTransform(SkMatrix::Scale(sx, sy), SkApplyPerspectiveClip::kNo); |
1389 | } |
1390 | |
1391 | /** Returns last point on SkPath in lastPt. Returns false if SkPoint array is empty, |
1392 | storing (0, 0) if lastPt is not nullptr. |
1393 | |
1394 | @param lastPt storage for final SkPoint in SkPoint array; may be nullptr |
1395 | @return true if SkPoint array contains one or more SkPoint |
1396 | |
1397 | example: https://fiddle.skia.org/c/@Path_getLastPt |
1398 | */ |
1399 | bool getLastPt(SkPoint* lastPt) const; |
1400 | |
1401 | /** Sets last point to (x, y). If SkPoint array is empty, append kMove_Verb to |
1402 | verb array and append (x, y) to SkPoint array. |
1403 | |
1404 | @param x set x-axis value of last point |
1405 | @param y set y-axis value of last point |
1406 | |
1407 | example: https://fiddle.skia.org/c/@Path_setLastPt |
1408 | */ |
1409 | void setLastPt(SkScalar x, SkScalar y); |
1410 | |
1411 | /** Sets the last point on the path. If SkPoint array is empty, append kMove_Verb to |
1412 | verb array and append p to SkPoint array. |
1413 | |
1414 | @param p set value of last point |
1415 | */ |
1416 | void setLastPt(const SkPoint& p) { |
1417 | this->setLastPt(p.fX, p.fY); |
1418 | } |
1419 | |
1420 | /** \enum SkPath::SegmentMask |
1421 | SegmentMask constants correspond to each drawing Verb type in SkPath; for |
1422 | instance, if SkPath only contains lines, only the kLine_SegmentMask bit is set. |
1423 | */ |
1424 | enum SegmentMask { |
1425 | kLine_SegmentMask = kLine_SkPathSegmentMask, |
1426 | kQuad_SegmentMask = kQuad_SkPathSegmentMask, |
1427 | kConic_SegmentMask = kConic_SkPathSegmentMask, |
1428 | kCubic_SegmentMask = kCubic_SkPathSegmentMask, |
1429 | }; |
1430 | |
1431 | /** Returns a mask, where each set bit corresponds to a SegmentMask constant |
1432 | if SkPath contains one or more verbs of that type. |
1433 | Returns zero if SkPath contains no lines, or curves: quads, conics, or cubics. |
1434 | |
1435 | getSegmentMasks() returns a cached result; it is very fast. |
1436 | |
1437 | @return SegmentMask bits or zero |
1438 | */ |
1439 | uint32_t getSegmentMasks() const { return fPathRef->getSegmentMasks(); } |
1440 | |
1441 | /** \enum SkPath::Verb |
1442 | Verb instructs SkPath how to interpret one or more SkPoint and optional conic weight; |
1443 | manage contour, and terminate SkPath. |
1444 | */ |
1445 | enum Verb { |
1446 | kMove_Verb = static_cast<int>(SkPathVerb::kMove), |
1447 | kLine_Verb = static_cast<int>(SkPathVerb::kLine), |
1448 | kQuad_Verb = static_cast<int>(SkPathVerb::kQuad), |
1449 | kConic_Verb = static_cast<int>(SkPathVerb::kConic), |
1450 | kCubic_Verb = static_cast<int>(SkPathVerb::kCubic), |
1451 | kClose_Verb = static_cast<int>(SkPathVerb::kClose), |
1452 | kDone_Verb = kClose_Verb + 1 |
1453 | }; |
1454 | |
1455 | /** \class SkPath::Iter |
1456 | Iterates through verb array, and associated SkPoint array and conic weight. |
1457 | Provides options to treat open contours as closed, and to ignore |
1458 | degenerate data. |
1459 | */ |
1460 | class SK_API Iter { |
1461 | public: |
1462 | |
1463 | /** Initializes SkPath::Iter with an empty SkPath. next() on SkPath::Iter returns |
1464 | kDone_Verb. |
1465 | Call setPath to initialize SkPath::Iter at a later time. |
1466 | |
1467 | @return SkPath::Iter of empty SkPath |
1468 | |
1469 | example: https://fiddle.skia.org/c/@Path_Iter_Iter |
1470 | */ |
1471 | Iter(); |
1472 | |
1473 | /** Sets SkPath::Iter to return elements of verb array, SkPoint array, and conic weight in |
1474 | path. If forceClose is true, SkPath::Iter will add kLine_Verb and kClose_Verb after each |
1475 | open contour. path is not altered. |
1476 | |
1477 | @param path SkPath to iterate |
1478 | @param forceClose true if open contours generate kClose_Verb |
1479 | @return SkPath::Iter of path |
1480 | |
1481 | example: https://fiddle.skia.org/c/@Path_Iter_const_SkPath |
1482 | */ |
1483 | Iter(const SkPath& path, bool forceClose); |
1484 | |
1485 | /** Sets SkPath::Iter to return elements of verb array, SkPoint array, and conic weight in |
1486 | path. If forceClose is true, SkPath::Iter will add kLine_Verb and kClose_Verb after each |
1487 | open contour. path is not altered. |
1488 | |
1489 | @param path SkPath to iterate |
1490 | @param forceClose true if open contours generate kClose_Verb |
1491 | |
1492 | example: https://fiddle.skia.org/c/@Path_Iter_setPath |
1493 | */ |
1494 | void setPath(const SkPath& path, bool forceClose); |
1495 | |
1496 | /** Returns next SkPath::Verb in verb array, and advances SkPath::Iter. |
1497 | When verb array is exhausted, returns kDone_Verb. |
1498 | |
1499 | Zero to four SkPoint are stored in pts, depending on the returned SkPath::Verb. |
1500 | |
1501 | @param pts storage for SkPoint data describing returned SkPath::Verb |
1502 | @return next SkPath::Verb from verb array |
1503 | |
1504 | example: https://fiddle.skia.org/c/@Path_RawIter_next |
1505 | */ |
1506 | Verb next(SkPoint pts[4]); |
1507 | |
1508 | /** Returns conic weight if next() returned kConic_Verb. |
1509 | |
1510 | If next() has not been called, or next() did not return kConic_Verb, |
1511 | result is undefined. |
1512 | |
1513 | @return conic weight for conic SkPoint returned by next() |
1514 | */ |
1515 | SkScalar conicWeight() const { return *fConicWeights; } |
1516 | |
1517 | /** Returns true if last kLine_Verb returned by next() was generated |
1518 | by kClose_Verb. When true, the end point returned by next() is |
1519 | also the start point of contour. |
1520 | |
1521 | If next() has not been called, or next() did not return kLine_Verb, |
1522 | result is undefined. |
1523 | |
1524 | @return true if last kLine_Verb was generated by kClose_Verb |
1525 | */ |
1526 | bool isCloseLine() const { return SkToBool(fCloseLine); } |
1527 | |
1528 | /** Returns true if subsequent calls to next() return kClose_Verb before returning |
1529 | kMove_Verb. if true, contour SkPath::Iter is processing may end with kClose_Verb, or |
1530 | SkPath::Iter may have been initialized with force close set to true. |
1531 | |
1532 | @return true if contour is closed |
1533 | |
1534 | example: https://fiddle.skia.org/c/@Path_Iter_isClosedContour |
1535 | */ |
1536 | bool isClosedContour() const; |
1537 | |
1538 | private: |
1539 | const SkPoint* fPts; |
1540 | const uint8_t* fVerbs; |
1541 | const uint8_t* fVerbStop; |
1542 | const SkScalar* fConicWeights; |
1543 | SkPoint fMoveTo; |
1544 | SkPoint fLastPt; |
1545 | bool fForceClose; |
1546 | bool fNeedClose; |
1547 | bool fCloseLine; |
1548 | enum SegmentState : uint8_t { |
1549 | /** The current contour is empty. Starting processing or have just closed a contour. */ |
1550 | kEmptyContour_SegmentState, |
1551 | /** Have seen a move, but nothing else. */ |
1552 | kAfterMove_SegmentState, |
1553 | /** Have seen a primitive but not yet closed the path. Also the initial state. */ |
1554 | kAfterPrimitive_SegmentState |
1555 | }; |
1556 | SegmentState fSegmentState; |
1557 | |
1558 | inline const SkPoint& cons_moveTo(); |
1559 | Verb autoClose(SkPoint pts[2]); |
1560 | }; |
1561 | |
1562 | SkPathView view() const; |
1563 | |
1564 | private: |
1565 | /** \class SkPath::RangeIter |
1566 | Iterates through a raw range of path verbs, points, and conics. All values are returned |
1567 | unaltered. |
1568 | |
1569 | NOTE: This class will be moved into SkPathPriv once RangeIter is removed. |
1570 | */ |
1571 | class RangeIter { |
1572 | public: |
1573 | RangeIter() = default; |
1574 | RangeIter(const uint8_t* verbs, const SkPoint* points, const SkScalar* weights) |
1575 | : fVerb(verbs), fPoints(points), fWeights(weights) { |
1576 | SkDEBUGCODE(fInitialPoints = fPoints;) |
1577 | } |
1578 | bool operator!=(const RangeIter& that) const { |
1579 | return fVerb != that.fVerb; |
1580 | } |
1581 | bool operator==(const RangeIter& that) const { |
1582 | return fVerb == that.fVerb; |
1583 | } |
1584 | RangeIter& operator++() { |
1585 | auto verb = static_cast<SkPathVerb>(*fVerb++); |
1586 | fPoints += pts_advance_after_verb(verb); |
1587 | if (verb == SkPathVerb::kConic) { |
1588 | ++fWeights; |
1589 | } |
1590 | return *this; |
1591 | } |
1592 | RangeIter operator++(int) { |
1593 | RangeIter copy = *this; |
1594 | this->operator++(); |
1595 | return copy; |
1596 | } |
1597 | SkPathVerb peekVerb() const { |
1598 | return static_cast<SkPathVerb>(*fVerb); |
1599 | } |
1600 | std::tuple<SkPathVerb, const SkPoint*, const SkScalar*> operator*() const { |
1601 | SkPathVerb verb = this->peekVerb(); |
1602 | // We provide the starting point for beziers by peeking backwards from the current |
1603 | // point, which works fine as long as there is always a kMove before any geometry. |
1604 | // (SkPath::injectMoveToIfNeeded should have guaranteed this to be the case.) |
1605 | int backset = pts_backset_for_verb(verb); |
1606 | SkASSERT(fPoints + backset >= fInitialPoints); |
1607 | return {verb, fPoints + backset, fWeights}; |
1608 | } |
1609 | private: |
1610 | constexpr static int pts_advance_after_verb(SkPathVerb verb) { |
1611 | switch (verb) { |
1612 | case SkPathVerb::kMove: return 1; |
1613 | case SkPathVerb::kLine: return 1; |
1614 | case SkPathVerb::kQuad: return 2; |
1615 | case SkPathVerb::kConic: return 2; |
1616 | case SkPathVerb::kCubic: return 3; |
1617 | case SkPathVerb::kClose: return 0; |
1618 | } |
1619 | SkUNREACHABLE; |
1620 | } |
1621 | constexpr static int pts_backset_for_verb(SkPathVerb verb) { |
1622 | switch (verb) { |
1623 | case SkPathVerb::kMove: return 0; |
1624 | case SkPathVerb::kLine: return -1; |
1625 | case SkPathVerb::kQuad: return -1; |
1626 | case SkPathVerb::kConic: return -1; |
1627 | case SkPathVerb::kCubic: return -1; |
1628 | case SkPathVerb::kClose: return 0; |
1629 | } |
1630 | SkUNREACHABLE; |
1631 | } |
1632 | const uint8_t* fVerb = nullptr; |
1633 | const SkPoint* fPoints = nullptr; |
1634 | const SkScalar* fWeights = nullptr; |
1635 | SkDEBUGCODE(const SkPoint* fInitialPoints = nullptr;) |
1636 | }; |
1637 | public: |
1638 | |
1639 | /** \class SkPath::RawIter |
1640 | Use Iter instead. This class will soon be removed and RangeIter will be made private. |
1641 | */ |
1642 | class SK_API RawIter { |
1643 | public: |
1644 | |
1645 | /** Initializes RawIter with an empty SkPath. next() on RawIter returns kDone_Verb. |
1646 | Call setPath to initialize SkPath::Iter at a later time. |
1647 | |
1648 | @return RawIter of empty SkPath |
1649 | */ |
1650 | RawIter() {} |
1651 | |
1652 | /** Sets RawIter to return elements of verb array, SkPoint array, and conic weight in path. |
1653 | |
1654 | @param path SkPath to iterate |
1655 | @return RawIter of path |
1656 | */ |
1657 | RawIter(const SkPath& path) { |
1658 | setPath(path); |
1659 | } |
1660 | |
1661 | /** Sets SkPath::Iter to return elements of verb array, SkPoint array, and conic weight in |
1662 | path. |
1663 | |
1664 | @param path SkPath to iterate |
1665 | */ |
1666 | void setPath(const SkPath&); |
1667 | |
1668 | /** Returns next SkPath::Verb in verb array, and advances RawIter. |
1669 | When verb array is exhausted, returns kDone_Verb. |
1670 | Zero to four SkPoint are stored in pts, depending on the returned SkPath::Verb. |
1671 | |
1672 | @param pts storage for SkPoint data describing returned SkPath::Verb |
1673 | @return next SkPath::Verb from verb array |
1674 | */ |
1675 | Verb next(SkPoint[4]); |
1676 | |
1677 | /** Returns next SkPath::Verb, but does not advance RawIter. |
1678 | |
1679 | @return next SkPath::Verb from verb array |
1680 | */ |
1681 | Verb peek() const { |
1682 | return (fIter != fEnd) ? static_cast<Verb>(std::get<0>(*fIter)) : kDone_Verb; |
1683 | } |
1684 | |
1685 | /** Returns conic weight if next() returned kConic_Verb. |
1686 | |
1687 | If next() has not been called, or next() did not return kConic_Verb, |
1688 | result is undefined. |
1689 | |
1690 | @return conic weight for conic SkPoint returned by next() |
1691 | */ |
1692 | SkScalar conicWeight() const { |
1693 | return fConicWeight; |
1694 | } |
1695 | |
1696 | private: |
1697 | RangeIter fIter; |
1698 | RangeIter fEnd; |
1699 | SkScalar fConicWeight = 0; |
1700 | friend class SkPath; |
1701 | |
1702 | }; |
1703 | |
1704 | /** Returns true if the point (x, y) is contained by SkPath, taking into |
1705 | account FillType. |
1706 | |
1707 | @param x x-axis value of containment test |
1708 | @param y y-axis value of containment test |
1709 | @return true if SkPoint is in SkPath |
1710 | |
1711 | example: https://fiddle.skia.org/c/@Path_contains |
1712 | */ |
1713 | bool contains(SkScalar x, SkScalar y) const; |
1714 | |
1715 | /** Writes text representation of SkPath to stream. If stream is nullptr, writes to |
1716 | standard output. Set forceClose to true to get edges used to fill SkPath. |
1717 | Set dumpAsHex true to generate exact binary representations |
1718 | of floating point numbers used in SkPoint array and conic weights. |
1719 | |
1720 | @param stream writable SkWStream receiving SkPath text representation; may be nullptr |
1721 | @param forceClose true if missing kClose_Verb is output |
1722 | @param dumpAsHex true if SkScalar values are written as hexadecimal |
1723 | |
1724 | example: https://fiddle.skia.org/c/@Path_dump |
1725 | */ |
1726 | void dump(SkWStream* stream, bool forceClose, bool dumpAsHex) const; |
1727 | |
1728 | /** Writes text representation of SkPath to standard output. The representation may be |
1729 | directly compiled as C++ code. Floating point values are written |
1730 | with limited precision; it may not be possible to reconstruct original SkPath |
1731 | from output. |
1732 | |
1733 | example: https://fiddle.skia.org/c/@Path_dump_2 |
1734 | */ |
1735 | void dump() const; |
1736 | |
1737 | /** Writes text representation of SkPath to standard output. The representation may be |
1738 | directly compiled as C++ code. Floating point values are written |
1739 | in hexadecimal to preserve their exact bit pattern. The output reconstructs the |
1740 | original SkPath. |
1741 | |
1742 | Use instead of dump() when submitting |
1743 | |
1744 | example: https://fiddle.skia.org/c/@Path_dumpHex |
1745 | */ |
1746 | void dumpHex() const; |
1747 | |
1748 | /** Writes SkPath to buffer, returning the number of bytes written. |
1749 | Pass nullptr to obtain the storage size. |
1750 | |
1751 | Writes SkPath::FillType, verb array, SkPoint array, conic weight, and |
1752 | additionally writes computed information like SkPath::Convexity and bounds. |
1753 | |
1754 | Use only be used in concert with readFromMemory(); |
1755 | the format used for SkPath in memory is not guaranteed. |
1756 | |
1757 | @param buffer storage for SkPath; may be nullptr |
1758 | @return size of storage required for SkPath; always a multiple of 4 |
1759 | |
1760 | example: https://fiddle.skia.org/c/@Path_writeToMemory |
1761 | */ |
1762 | size_t writeToMemory(void* buffer) const; |
1763 | |
1764 | /** Writes SkPath to buffer, returning the buffer written to, wrapped in SkData. |
1765 | |
1766 | serialize() writes SkPath::FillType, verb array, SkPoint array, conic weight, and |
1767 | additionally writes computed information like SkPath::Convexity and bounds. |
1768 | |
1769 | serialize() should only be used in concert with readFromMemory(). |
1770 | The format used for SkPath in memory is not guaranteed. |
1771 | |
1772 | @return SkPath data wrapped in SkData buffer |
1773 | |
1774 | example: https://fiddle.skia.org/c/@Path_serialize |
1775 | */ |
1776 | sk_sp<SkData> serialize() const; |
1777 | |
1778 | /** Initializes SkPath from buffer of size length. Returns zero if the buffer is |
1779 | data is inconsistent, or the length is too small. |
1780 | |
1781 | Reads SkPath::FillType, verb array, SkPoint array, conic weight, and |
1782 | additionally reads computed information like SkPath::Convexity and bounds. |
1783 | |
1784 | Used only in concert with writeToMemory(); |
1785 | the format used for SkPath in memory is not guaranteed. |
1786 | |
1787 | @param buffer storage for SkPath |
1788 | @param length buffer size in bytes; must be multiple of 4 |
1789 | @return number of bytes read, or zero on failure |
1790 | |
1791 | example: https://fiddle.skia.org/c/@Path_readFromMemory |
1792 | */ |
1793 | size_t readFromMemory(const void* buffer, size_t length); |
1794 | |
1795 | /** (See Skia bug 1762.) |
1796 | Returns a non-zero, globally unique value. A different value is returned |
1797 | if verb array, SkPoint array, or conic weight changes. |
1798 | |
1799 | Setting SkPath::FillType does not change generation identifier. |
1800 | |
1801 | Each time the path is modified, a different generation identifier will be returned. |
1802 | SkPath::FillType does affect generation identifier on Android framework. |
1803 | |
1804 | @return non-zero, globally unique value |
1805 | |
1806 | example: https://fiddle.skia.org/c/@Path_getGenerationID |
1807 | */ |
1808 | uint32_t getGenerationID() const; |
1809 | |
1810 | /** Returns if SkPath data is consistent. Corrupt SkPath data is detected if |
1811 | internal values are out of range or internal storage does not match |
1812 | array dimensions. |
1813 | |
1814 | @return true if SkPath data is consistent |
1815 | */ |
1816 | bool isValid() const { return this->isValidImpl() && fPathRef->isValid(); } |
1817 | |
1818 | private: |
1819 | SkPath(sk_sp<SkPathRef>, SkPathFillType, bool isVolatile); |
1820 | |
1821 | sk_sp<SkPathRef> fPathRef; |
1822 | int fLastMoveToIndex; |
1823 | mutable std::atomic<uint8_t> fConvexity; // SkPathConvexityType |
1824 | mutable std::atomic<uint8_t> fFirstDirection; // really an SkPathPriv::FirstDirection |
1825 | uint8_t fFillType : 2; |
1826 | uint8_t fIsVolatile : 1; |
1827 | |
1828 | /** Resets all fields other than fPathRef to their initial 'empty' values. |
1829 | * Assumes the caller has already emptied fPathRef. |
1830 | * On Android increments fGenerationID without reseting it. |
1831 | */ |
1832 | void resetFields(); |
1833 | |
1834 | /** Sets all fields other than fPathRef to the values in 'that'. |
1835 | * Assumes the caller has already set fPathRef. |
1836 | * Doesn't change fGenerationID or fSourcePath on Android. |
1837 | */ |
1838 | void copyFields(const SkPath& that); |
1839 | |
1840 | size_t writeToMemoryAsRRect(void* buffer) const; |
1841 | size_t readAsRRect(const void*, size_t); |
1842 | size_t readFromMemory_EQ4Or5(const void*, size_t); |
1843 | |
1844 | friend class Iter; |
1845 | friend class SkPathPriv; |
1846 | friend class SkPathStroker; |
1847 | |
1848 | /* Append, in reverse order, the first contour of path, ignoring path's |
1849 | last point. If no moveTo() call has been made for this contour, the |
1850 | first point is automatically set to (0,0). |
1851 | */ |
1852 | SkPath& reversePathTo(const SkPath&); |
1853 | |
1854 | // called before we add points for lineTo, quadTo, cubicTo, checking to see |
1855 | // if we need to inject a leading moveTo first |
1856 | // |
1857 | // SkPath path; path.lineTo(...); <--- need a leading moveTo(0, 0) |
1858 | // SkPath path; ... path.close(); path.lineTo(...) <-- need a moveTo(previous moveTo) |
1859 | // |
1860 | inline void injectMoveToIfNeeded(); |
1861 | |
1862 | inline bool hasOnlyMoveTos() const; |
1863 | |
1864 | SkPathConvexityType internalGetConvexity() const; |
1865 | |
1866 | /** Asserts if SkPath data is inconsistent. |
1867 | Debugging check intended for internal use only. |
1868 | */ |
1869 | SkDEBUGCODE(void validate() const { SkASSERT(this->isValidImpl()); } ) |
1870 | bool isValidImpl() const; |
1871 | SkDEBUGCODE(void validateRef() const { fPathRef->validate(); } ) |
1872 | |
1873 | // called by stroker to see if all points (in the last contour) are equal and worthy of a cap |
1874 | bool isZeroLengthSincePoint(int startPtIndex) const; |
1875 | |
1876 | /** Returns if the path can return a bound at no cost (true) or will have to |
1877 | perform some computation (false). |
1878 | */ |
1879 | bool hasComputedBounds() const { |
1880 | SkDEBUGCODE(this->validate();) |
1881 | return fPathRef->hasComputedBounds(); |
1882 | } |
1883 | |
1884 | |
1885 | // 'rect' needs to be sorted |
1886 | void setBounds(const SkRect& rect) { |
1887 | SkPathRef::Editor ed(&fPathRef); |
1888 | |
1889 | ed.setBounds(rect); |
1890 | } |
1891 | |
1892 | void setPt(int index, SkScalar x, SkScalar y); |
1893 | |
1894 | SkPath& dirtyAfterEdit(); |
1895 | |
1896 | // Bottlenecks for working with fConvexity and fFirstDirection. |
1897 | // Notice the setters are const... these are mutable atomic fields. |
1898 | void setConvexityType(SkPathConvexityType) const; |
1899 | void setFirstDirection(uint8_t) const; |
1900 | uint8_t getFirstDirection() const; |
1901 | |
1902 | friend class SkAutoPathBoundsUpdate; |
1903 | friend class SkAutoDisableOvalCheck; |
1904 | friend class SkAutoDisableDirectionCheck; |
1905 | friend class SkPathBuilder; |
1906 | friend class SkPathEdgeIter; |
1907 | friend class SkPathWriter; |
1908 | friend class SkOpBuilder; |
1909 | friend class SkBench_AddPathTest; // perf test reversePathTo |
1910 | friend class PathTest_Private; // unit test reversePathTo |
1911 | friend class ForceIsRRect_Private; // unit test isRRect |
1912 | friend class FuzzPath; // for legacy access to validateRef |
1913 | }; |
1914 | |
1915 | #endif |
1916 | |