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 SkRect_DEFINED
9 #define SkRect_DEFINED
10 
11 #include "SkPoint.h"
12 #include "SkSize.h"
13 
14 struct SkRect;
15 
16 /** \struct SkIRect
17 
18     SkIRect holds four 32 bit integer coordinates for a rectangle
19 */
20 struct SK_API SkIRect {
21     int32_t fLeft, fTop, fRight, fBottom;
22 
MakeEmptySkIRect23     static SkIRect SK_WARN_UNUSED_RESULT MakeEmpty() {
24         SkIRect r;
25         r.setEmpty();
26         return r;
27     }
28 
MakeLargestSkIRect29     static SkIRect SK_WARN_UNUSED_RESULT MakeLargest() {
30         SkIRect r;
31         r.setLargest();
32         return r;
33     }
34 
MakeWHSkIRect35     static SkIRect SK_WARN_UNUSED_RESULT MakeWH(int32_t w, int32_t h) {
36         SkIRect r;
37         r.set(0, 0, w, h);
38         return r;
39     }
40 
MakeSizeSkIRect41     static SkIRect SK_WARN_UNUSED_RESULT MakeSize(const SkISize& size) {
42         SkIRect r;
43         r.set(0, 0, size.width(), size.height());
44         return r;
45     }
46 
MakeLTRBSkIRect47     static SkIRect SK_WARN_UNUSED_RESULT MakeLTRB(int32_t l, int32_t t, int32_t r, int32_t b) {
48         SkIRect rect;
49         rect.set(l, t, r, b);
50         return rect;
51     }
52 
MakeXYWHSkIRect53     static SkIRect SK_WARN_UNUSED_RESULT MakeXYWH(int32_t x, int32_t y, int32_t w, int32_t h) {
54         SkIRect r;
55         r.set(x, y, x + w, y + h);
56         return r;
57     }
58 
leftSkIRect59     int left() const { return fLeft; }
topSkIRect60     int top() const { return fTop; }
rightSkIRect61     int right() const { return fRight; }
bottomSkIRect62     int bottom() const { return fBottom; }
63 
64     /** return the left edge of the rect */
xSkIRect65     int x() const { return fLeft; }
66     /** return the top edge of the rect */
ySkIRect67     int y() const { return fTop; }
68     /**
69      *  Returns the rectangle's width. This does not check for a valid rect
70      *  (i.e. left <= right) so the result may be negative.
71      */
widthSkIRect72     int width() const { return fRight - fLeft; }
73 
74     /**
75      *  Returns the rectangle's height. This does not check for a valid rect
76      *  (i.e. top <= bottom) so the result may be negative.
77      */
heightSkIRect78     int height() const { return fBottom - fTop; }
79 
sizeSkIRect80     SkISize size() const { return SkISize::Make(this->width(), this->height()); }
81 
82     /**
83      *  Since the center of an integer rect may fall on a factional value, this
84      *  method is defined to return (right + left) >> 1.
85      *
86      *  This is a specific "truncation" of the average, which is different than
87      *  (right + left) / 2 when the sum is negative.
88      */
centerXSkIRect89     int centerX() const { return (fRight + fLeft) >> 1; }
90 
91     /**
92      *  Since the center of an integer rect may fall on a factional value, this
93      *  method is defined to return (bottom + top) >> 1
94      *
95      *  This is a specific "truncation" of the average, which is different than
96      *  (bottom + top) / 2 when the sum is negative.
97      */
centerYSkIRect98     int centerY() const { return (fBottom + fTop) >> 1; }
99 
100     /**
101      *  Return true if the rectangle's width or height are <= 0
102      */
isEmptySkIRect103     bool isEmpty() const { return fLeft >= fRight || fTop >= fBottom; }
104 
isLargestSkIRect105     bool isLargest() const { return SK_MinS32 == fLeft &&
106                                     SK_MinS32 == fTop &&
107                                     SK_MaxS32 == fRight &&
108                                     SK_MaxS32 == fBottom; }
109 
110     friend bool operator==(const SkIRect& a, const SkIRect& b) {
111         return !memcmp(&a, &b, sizeof(a));
112     }
113 
114     friend bool operator!=(const SkIRect& a, const SkIRect& b) {
115         return !(a == b);
116     }
117 
is16BitSkIRect118     bool is16Bit() const {
119         return  SkIsS16(fLeft) && SkIsS16(fTop) &&
120                 SkIsS16(fRight) && SkIsS16(fBottom);
121     }
122 
123     /** Set the rectangle to (0,0,0,0)
124     */
setEmptySkIRect125     void setEmpty() { memset(this, 0, sizeof(*this)); }
126 
setSkIRect127     void set(int32_t left, int32_t top, int32_t right, int32_t bottom) {
128         fLeft   = left;
129         fTop    = top;
130         fRight  = right;
131         fBottom = bottom;
132     }
133     // alias for set(l, t, r, b)
setLTRBSkIRect134     void setLTRB(int32_t left, int32_t top, int32_t right, int32_t bottom) {
135         this->set(left, top, right, bottom);
136     }
137 
setXYWHSkIRect138     void setXYWH(int32_t x, int32_t y, int32_t width, int32_t height) {
139         fLeft = x;
140         fTop = y;
141         fRight = x + width;
142         fBottom = y + height;
143     }
144 
145     /**
146      *  Make the largest representable rectangle
147      */
setLargestSkIRect148     void setLargest() {
149         fLeft = fTop = SK_MinS32;
150         fRight = fBottom = SK_MaxS32;
151     }
152 
153     /**
154      *  Make the largest representable rectangle, but inverted (e.g. fLeft will
155      *  be max 32bit and right will be min 32bit).
156      */
setLargestInvertedSkIRect157     void setLargestInverted() {
158         fLeft = fTop = SK_MaxS32;
159         fRight = fBottom = SK_MinS32;
160     }
161 
162     /**
163      *  Return a new IRect, built as an offset of this rect.
164      */
makeOffsetSkIRect165     SkIRect makeOffset(int32_t dx, int32_t dy) const {
166         return MakeLTRB(fLeft + dx, fTop + dy, fRight + dx, fBottom + dy);
167     }
168 
169     /**
170      *  Return a new IRect, built as an inset of this rect.
171      */
makeInsetSkIRect172     SkIRect makeInset(int32_t dx, int32_t dy) const {
173         return MakeLTRB(fLeft + dx, fTop + dy, fRight - dx, fBottom - dy);
174     }
175 
176     /**
177      *  Return a new Rect, built as an outset of this rect.
178      */
makeOutsetSkIRect179     SkIRect makeOutset(int32_t dx, int32_t dy) const {
180         return MakeLTRB(fLeft - dx, fTop - dy, fRight + dx, fBottom + dy);
181     }
182 
183     /** Offset set the rectangle by adding dx to its left and right,
184         and adding dy to its top and bottom.
185     */
offsetSkIRect186     void offset(int32_t dx, int32_t dy) {
187         fLeft   += dx;
188         fTop    += dy;
189         fRight  += dx;
190         fBottom += dy;
191     }
192 
offsetSkIRect193     void offset(const SkIPoint& delta) {
194         this->offset(delta.fX, delta.fY);
195     }
196 
197     /**
198      *  Offset this rect such its new x() and y() will equal newX and newY.
199      */
offsetToSkIRect200     void offsetTo(int32_t newX, int32_t newY) {
201         fRight += newX - fLeft;
202         fBottom += newY - fTop;
203         fLeft = newX;
204         fTop = newY;
205     }
206 
207     /** Inset the rectangle by (dx,dy). If dx is positive, then the sides are moved inwards,
208         making the rectangle narrower. If dx is negative, then the sides are moved outwards,
209         making the rectangle wider. The same holds true for dy and the top and bottom.
210     */
insetSkIRect211     void inset(int32_t dx, int32_t dy) {
212         fLeft   += dx;
213         fTop    += dy;
214         fRight  -= dx;
215         fBottom -= dy;
216     }
217 
218    /** Outset the rectangle by (dx,dy). If dx is positive, then the sides are
219        moved outwards, making the rectangle wider. If dx is negative, then the
220        sides are moved inwards, making the rectangle narrower. The same holds
221        true for dy and the top and bottom.
222     */
outsetSkIRect223     void outset(int32_t dx, int32_t dy)  { this->inset(-dx, -dy); }
224 
quickRejectSkIRect225     bool quickReject(int l, int t, int r, int b) const {
226         return l >= fRight || fLeft >= r || t >= fBottom || fTop >= b;
227     }
228 
229     /** Returns true if (x,y) is inside the rectangle and the rectangle is not
230         empty. The left and top are considered to be inside, while the right
231         and bottom are not. Thus for the rectangle (0, 0, 5, 10), the
232         points (0,0) and (0,9) are inside, while (-1,0) and (5,9) are not.
233     */
containsSkIRect234     bool contains(int32_t x, int32_t y) const {
235         return  (unsigned)(x - fLeft) < (unsigned)(fRight - fLeft) &&
236                 (unsigned)(y - fTop) < (unsigned)(fBottom - fTop);
237     }
238 
239     /** Returns true if the 4 specified sides of a rectangle are inside or equal to this rectangle.
240         If either rectangle is empty, contains() returns false.
241     */
containsSkIRect242     bool contains(int32_t left, int32_t top, int32_t right, int32_t bottom) const {
243         return  left < right && top < bottom && !this->isEmpty() && // check for empties
244                 fLeft <= left && fTop <= top &&
245                 fRight >= right && fBottom >= bottom;
246     }
247 
248     /** Returns true if the specified rectangle r is inside or equal to this rectangle.
249     */
containsSkIRect250     bool contains(const SkIRect& r) const {
251         return  !r.isEmpty() && !this->isEmpty() &&     // check for empties
252                 fLeft <= r.fLeft && fTop <= r.fTop &&
253                 fRight >= r.fRight && fBottom >= r.fBottom;
254     }
255 
256     /** Returns true if the specified rectangle r is inside or equal to this rectangle.
257     */
258     bool contains(const SkRect& r) const;
259 
260     /** Return true if this rectangle contains the specified rectangle.
261         For speed, this method does not check if either this or the specified
262         rectangles are empty, and if either is, its return value is undefined.
263         In the debugging build however, we assert that both this and the
264         specified rectangles are non-empty.
265     */
containsNoEmptyCheckSkIRect266     bool containsNoEmptyCheck(int32_t left, int32_t top,
267                               int32_t right, int32_t bottom) const {
268         SkASSERT(fLeft < fRight && fTop < fBottom);
269         SkASSERT(left < right && top < bottom);
270 
271         return fLeft <= left && fTop <= top &&
272                fRight >= right && fBottom >= bottom;
273     }
274 
containsNoEmptyCheckSkIRect275     bool containsNoEmptyCheck(const SkIRect& r) const {
276         return containsNoEmptyCheck(r.fLeft, r.fTop, r.fRight, r.fBottom);
277     }
278 
279     /** If r intersects this rectangle, return true and set this rectangle to that
280         intersection, otherwise return false and do not change this rectangle.
281         If either rectangle is empty, do nothing and return false.
282     */
intersectSkIRect283     bool SK_WARN_UNUSED_RESULT intersect(const SkIRect& r) {
284         return this->intersect(r.fLeft, r.fTop, r.fRight, r.fBottom);
285     }
286 
287     /** If rectangles a and b intersect, return true and set this rectangle to
288         that intersection, otherwise return false and do not change this
289         rectangle. If either rectangle is empty, do nothing and return false.
290     */
intersectSkIRect291     bool SK_WARN_UNUSED_RESULT intersect(const SkIRect& a, const SkIRect& b) {
292 
293         if (!a.isEmpty() && !b.isEmpty() &&
294                 a.fLeft < b.fRight && b.fLeft < a.fRight &&
295                 a.fTop < b.fBottom && b.fTop < a.fBottom) {
296             fLeft   = SkMax32(a.fLeft,   b.fLeft);
297             fTop    = SkMax32(a.fTop,    b.fTop);
298             fRight  = SkMin32(a.fRight,  b.fRight);
299             fBottom = SkMin32(a.fBottom, b.fBottom);
300             return true;
301         }
302         return false;
303     }
304 
305     /** If rectangles a and b intersect, return true and set this rectangle to
306         that intersection, otherwise return false and do not change this
307         rectangle. For speed, no check to see if a or b are empty is performed.
308         If either is, then the return result is undefined. In the debug build,
309         we assert that both rectangles are non-empty.
310     */
intersectNoEmptyCheckSkIRect311     bool SK_WARN_UNUSED_RESULT intersectNoEmptyCheck(const SkIRect& a, const SkIRect& b) {
312         SkASSERT(!a.isEmpty() && !b.isEmpty());
313 
314         if (a.fLeft < b.fRight && b.fLeft < a.fRight &&
315                 a.fTop < b.fBottom && b.fTop < a.fBottom) {
316             fLeft   = SkMax32(a.fLeft,   b.fLeft);
317             fTop    = SkMax32(a.fTop,    b.fTop);
318             fRight  = SkMin32(a.fRight,  b.fRight);
319             fBottom = SkMin32(a.fBottom, b.fBottom);
320             return true;
321         }
322         return false;
323     }
324 
325     /** If the rectangle specified by left,top,right,bottom intersects this rectangle,
326         return true and set this rectangle to that intersection,
327         otherwise return false and do not change this rectangle.
328         If either rectangle is empty, do nothing and return false.
329     */
intersectSkIRect330     bool SK_WARN_UNUSED_RESULT intersect(int32_t left, int32_t top,
331                                          int32_t right, int32_t bottom) {
332         if (left < right && top < bottom && !this->isEmpty() &&
333                 fLeft < right && left < fRight && fTop < bottom && top < fBottom) {
334             if (fLeft < left) fLeft = left;
335             if (fTop < top) fTop = top;
336             if (fRight > right) fRight = right;
337             if (fBottom > bottom) fBottom = bottom;
338             return true;
339         }
340         return false;
341     }
342 
343     /** Returns true if a and b are not empty, and they intersect
344      */
IntersectsSkIRect345     static bool Intersects(const SkIRect& a, const SkIRect& b) {
346         return  !a.isEmpty() && !b.isEmpty() &&              // check for empties
347                 a.fLeft < b.fRight && b.fLeft < a.fRight &&
348                 a.fTop < b.fBottom && b.fTop < a.fBottom;
349     }
350 
351     /**
352      *  Returns true if a and b intersect. debug-asserts that neither are empty.
353      */
IntersectsNoEmptyCheckSkIRect354     static bool IntersectsNoEmptyCheck(const SkIRect& a, const SkIRect& b) {
355         SkASSERT(!a.isEmpty());
356         SkASSERT(!b.isEmpty());
357         return  a.fLeft < b.fRight && b.fLeft < a.fRight &&
358                 a.fTop < b.fBottom && b.fTop < a.fBottom;
359     }
360 
361     /** Update this rectangle to enclose itself and the specified rectangle.
362         If this rectangle is empty, just set it to the specified rectangle. If the specified
363         rectangle is empty, do nothing.
364     */
365     void join(int32_t left, int32_t top, int32_t right, int32_t bottom);
366 
367     /** Update this rectangle to enclose itself and the specified rectangle.
368         If this rectangle is empty, just set it to the specified rectangle. If the specified
369         rectangle is empty, do nothing.
370     */
joinSkIRect371     void join(const SkIRect& r) {
372         this->join(r.fLeft, r.fTop, r.fRight, r.fBottom);
373     }
374 
375     /** Swap top/bottom or left/right if there are flipped.
376         This can be called if the edges are computed separately,
377         and may have crossed over each other.
378         When this returns, left <= right && top <= bottom
379     */
380     void sort();
381 
EmptyIRectSkIRect382     static const SkIRect& SK_WARN_UNUSED_RESULT EmptyIRect() {
383         static const SkIRect gEmpty = { 0, 0, 0, 0 };
384         return gEmpty;
385     }
386 };
387 
388 /** \struct SkRect
389 */
390 struct SK_API SkRect {
391     SkScalar    fLeft, fTop, fRight, fBottom;
392 
MakeEmptySkRect393     static SkRect SK_WARN_UNUSED_RESULT MakeEmpty() {
394         SkRect r;
395         r.setEmpty();
396         return r;
397     }
398 
MakeLargestSkRect399     static SkRect SK_WARN_UNUSED_RESULT MakeLargest() {
400         SkRect r;
401         r.setLargest();
402         return r;
403     }
404 
MakeWHSkRect405     static SkRect SK_WARN_UNUSED_RESULT MakeWH(SkScalar w, SkScalar h) {
406         SkRect r;
407         r.set(0, 0, w, h);
408         return r;
409     }
410 
MakeIWHSkRect411     static SkRect SK_WARN_UNUSED_RESULT MakeIWH(int w, int h) {
412         SkRect r;
413         r.set(0, 0, SkIntToScalar(w), SkIntToScalar(h));
414         return r;
415     }
416 
MakeSizeSkRect417     static SkRect SK_WARN_UNUSED_RESULT MakeSize(const SkSize& size) {
418         SkRect r;
419         r.set(0, 0, size.width(), size.height());
420         return r;
421     }
422 
MakeLTRBSkRect423     static SkRect SK_WARN_UNUSED_RESULT MakeLTRB(SkScalar l, SkScalar t, SkScalar r, SkScalar b) {
424         SkRect rect;
425         rect.set(l, t, r, b);
426         return rect;
427     }
428 
MakeXYWHSkRect429     static SkRect SK_WARN_UNUSED_RESULT MakeXYWH(SkScalar x, SkScalar y, SkScalar w, SkScalar h) {
430         SkRect r;
431         r.set(x, y, x + w, y + h);
432         return r;
433     }
434 
435     SK_ATTR_DEPRECATED("use Make()")
MakeFromIRectSkRect436     static SkRect SK_WARN_UNUSED_RESULT MakeFromIRect(const SkIRect& irect) {
437         SkRect r;
438         r.set(SkIntToScalar(irect.fLeft),
439               SkIntToScalar(irect.fTop),
440               SkIntToScalar(irect.fRight),
441               SkIntToScalar(irect.fBottom));
442         return r;
443     }
444 
MakeSkRect445     static SkRect SK_WARN_UNUSED_RESULT Make(const SkIRect& irect) {
446         SkRect r;
447         r.set(SkIntToScalar(irect.fLeft),
448               SkIntToScalar(irect.fTop),
449               SkIntToScalar(irect.fRight),
450               SkIntToScalar(irect.fBottom));
451         return r;
452     }
453 
454     /**
455      *  Return true if the rectangle's width or height are <= 0
456      */
isEmptySkRect457     bool isEmpty() const { return fLeft >= fRight || fTop >= fBottom; }
458 
isLargestSkRect459     bool isLargest() const { return SK_ScalarMin == fLeft &&
460                                     SK_ScalarMin == fTop &&
461                                     SK_ScalarMax == fRight &&
462                                     SK_ScalarMax == fBottom; }
463 
464     /**
465      *  Returns true iff all values in the rect are finite. If any are
466      *  infinite or NaN then this returns false.
467      */
isFiniteSkRect468     bool isFinite() const {
469         float accum = 0;
470         accum *= fLeft;
471         accum *= fTop;
472         accum *= fRight;
473         accum *= fBottom;
474 
475         // accum is either NaN or it is finite (zero).
476         SkASSERT(0 == accum || SkScalarIsNaN(accum));
477 
478         // value==value will be true iff value is not NaN
479         // TODO: is it faster to say !accum or accum==accum?
480         return !SkScalarIsNaN(accum);
481     }
482 
xSkRect483     SkScalar    x() const { return fLeft; }
ySkRect484     SkScalar    y() const { return fTop; }
leftSkRect485     SkScalar    left() const { return fLeft; }
topSkRect486     SkScalar    top() const { return fTop; }
rightSkRect487     SkScalar    right() const { return fRight; }
bottomSkRect488     SkScalar    bottom() const { return fBottom; }
widthSkRect489     SkScalar    width() const { return fRight - fLeft; }
heightSkRect490     SkScalar    height() const { return fBottom - fTop; }
centerXSkRect491     SkScalar    centerX() const { return SkScalarHalf(fLeft + fRight); }
centerYSkRect492     SkScalar    centerY() const { return SkScalarHalf(fTop + fBottom); }
493 
494     friend bool operator==(const SkRect& a, const SkRect& b) {
495         return SkScalarsEqual((SkScalar*)&a, (SkScalar*)&b, 4);
496     }
497 
498     friend bool operator!=(const SkRect& a, const SkRect& b) {
499         return !SkScalarsEqual((SkScalar*)&a, (SkScalar*)&b, 4);
500     }
501 
502     /** return the 4 points that enclose the rectangle (top-left, top-right, bottom-right,
503         bottom-left). TODO: Consider adding param to control whether quad is CW or CCW.
504      */
505     void toQuad(SkPoint quad[4]) const;
506 
507     /** Set this rectangle to the empty rectangle (0,0,0,0)
508     */
setEmptySkRect509     void setEmpty() { memset(this, 0, sizeof(*this)); }
510 
setSkRect511     void set(const SkIRect& src) {
512         fLeft   = SkIntToScalar(src.fLeft);
513         fTop    = SkIntToScalar(src.fTop);
514         fRight  = SkIntToScalar(src.fRight);
515         fBottom = SkIntToScalar(src.fBottom);
516     }
517 
setSkRect518     void set(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom) {
519         fLeft   = left;
520         fTop    = top;
521         fRight  = right;
522         fBottom = bottom;
523     }
524     // alias for set(l, t, r, b)
setLTRBSkRect525     void setLTRB(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom) {
526         this->set(left, top, right, bottom);
527     }
528 
529     /** Initialize the rect with the 4 specified integers. The routine handles
530         converting them to scalars (by calling SkIntToScalar)
531      */
isetSkRect532     void iset(int left, int top, int right, int bottom) {
533         fLeft   = SkIntToScalar(left);
534         fTop    = SkIntToScalar(top);
535         fRight  = SkIntToScalar(right);
536         fBottom = SkIntToScalar(bottom);
537     }
538 
539     /**
540      *  Set this rectangle to be left/top at 0,0, and have the specified width
541      *  and height (automatically converted to SkScalar).
542      */
isetWHSkRect543     void isetWH(int width, int height) {
544         fLeft = fTop = 0;
545         fRight = SkIntToScalar(width);
546         fBottom = SkIntToScalar(height);
547     }
548 
549     /** Set this rectangle to be the bounds of the array of points.
550         If the array is empty (count == 0), then set this rectangle
551         to the empty rectangle (0,0,0,0)
552     */
setSkRect553     void set(const SkPoint pts[], int count) {
554         // set() had been checking for non-finite values, so keep that behavior
555         // for now. Now that we have setBoundsCheck(), we may decide to make
556         // set() be simpler/faster, and not check for those.
557         (void)this->setBoundsCheck(pts, count);
558     }
559 
560     // alias for set(pts, count)
setBoundsSkRect561     void setBounds(const SkPoint pts[], int count) {
562         (void)this->setBoundsCheck(pts, count);
563     }
564 
565     /**
566      *  Compute the bounds of the array of points, and set this rect to that
567      *  bounds and return true... unless a non-finite value is encountered,
568      *  in which case this rect is set to empty and false is returned.
569      */
570     bool setBoundsCheck(const SkPoint pts[], int count);
571 
setSkRect572     void set(const SkPoint& p0, const SkPoint& p1) {
573         fLeft =   SkMinScalar(p0.fX, p1.fX);
574         fRight =  SkMaxScalar(p0.fX, p1.fX);
575         fTop =    SkMinScalar(p0.fY, p1.fY);
576         fBottom = SkMaxScalar(p0.fY, p1.fY);
577     }
578 
setXYWHSkRect579     void setXYWH(SkScalar x, SkScalar y, SkScalar width, SkScalar height) {
580         fLeft = x;
581         fTop = y;
582         fRight = x + width;
583         fBottom = y + height;
584     }
585 
setWHSkRect586     void setWH(SkScalar width, SkScalar height) {
587         fLeft = 0;
588         fTop = 0;
589         fRight = width;
590         fBottom = height;
591     }
592 
593     /**
594      *  Make the largest representable rectangle
595      */
setLargestSkRect596     void setLargest() {
597         fLeft = fTop = SK_ScalarMin;
598         fRight = fBottom = SK_ScalarMax;
599     }
600 
601     /**
602      *  Make the largest representable rectangle, but inverted (e.g. fLeft will
603      *  be max and right will be min).
604      */
setLargestInvertedSkRect605     void setLargestInverted() {
606         fLeft = fTop = SK_ScalarMax;
607         fRight = fBottom = SK_ScalarMin;
608     }
609 
610     /**
611      *  Return a new Rect, built as an offset of this rect.
612      */
makeOffsetSkRect613     SkRect makeOffset(SkScalar dx, SkScalar dy) const {
614         return MakeLTRB(fLeft + dx, fTop + dy, fRight + dx, fBottom + dy);
615     }
616 
617     /**
618      *  Return a new Rect, built as an inset of this rect.
619      */
makeInsetSkRect620     SkRect makeInset(SkScalar dx, SkScalar dy) const {
621         return MakeLTRB(fLeft + dx, fTop + dy, fRight - dx, fBottom - dy);
622     }
623 
624     /**
625      *  Return a new Rect, built as an outset of this rect.
626      */
makeOutsetSkRect627     SkRect makeOutset(SkScalar dx, SkScalar dy) const {
628         return MakeLTRB(fLeft - dx, fTop - dy, fRight + dx, fBottom + dy);
629     }
630 
631     /** Offset set the rectangle by adding dx to its left and right,
632         and adding dy to its top and bottom.
633     */
offsetSkRect634     void offset(SkScalar dx, SkScalar dy) {
635         fLeft   += dx;
636         fTop    += dy;
637         fRight  += dx;
638         fBottom += dy;
639     }
640 
offsetSkRect641     void offset(const SkPoint& delta) {
642         this->offset(delta.fX, delta.fY);
643     }
644 
645     /**
646      *  Offset this rect such its new x() and y() will equal newX and newY.
647      */
offsetToSkRect648     void offsetTo(SkScalar newX, SkScalar newY) {
649         fRight += newX - fLeft;
650         fBottom += newY - fTop;
651         fLeft = newX;
652         fTop = newY;
653     }
654 
655     /** Inset the rectangle by (dx,dy). If dx is positive, then the sides are
656         moved inwards, making the rectangle narrower. If dx is negative, then
657         the sides are moved outwards, making the rectangle wider. The same holds
658          true for dy and the top and bottom.
659     */
insetSkRect660     void inset(SkScalar dx, SkScalar dy)  {
661         fLeft   += dx;
662         fTop    += dy;
663         fRight  -= dx;
664         fBottom -= dy;
665     }
666 
667    /** Outset the rectangle by (dx,dy). If dx is positive, then the sides are
668        moved outwards, making the rectangle wider. If dx is negative, then the
669        sides are moved inwards, making the rectangle narrower. The same holds
670        true for dy and the top and bottom.
671     */
outsetSkRect672     void outset(SkScalar dx, SkScalar dy)  { this->inset(-dx, -dy); }
673 
674     /** If this rectangle intersects r, return true and set this rectangle to that
675         intersection, otherwise return false and do not change this rectangle.
676         If either rectangle is empty, do nothing and return false.
677     */
678     bool SK_WARN_UNUSED_RESULT intersect(const SkRect& r);
679 
680     /** If this rectangle intersects the rectangle specified by left, top, right, bottom,
681         return true and set this rectangle to that intersection, otherwise return false
682         and do not change this rectangle.
683         If either rectangle is empty, do nothing and return false.
684     */
685     bool SK_WARN_UNUSED_RESULT intersect(SkScalar left, SkScalar top,
686                                          SkScalar right, SkScalar bottom);
687 
688     /**
689      *  If rectangles a and b intersect, return true and set this rectangle to
690      *  that intersection, otherwise return false and do not change this
691      *  rectangle. If either rectangle is empty, do nothing and return false.
692      */
693     bool SK_WARN_UNUSED_RESULT intersect(const SkRect& a, const SkRect& b);
694 
695 
696 private:
IntersectsSkRect697     static bool Intersects(SkScalar al, SkScalar at, SkScalar ar, SkScalar ab,
698                            SkScalar bl, SkScalar bt, SkScalar br, SkScalar bb) {
699         SkScalar L = SkMaxScalar(al, bl);
700         SkScalar R = SkMinScalar(ar, br);
701         SkScalar T = SkMaxScalar(at, bt);
702         SkScalar B = SkMinScalar(ab, bb);
703         return L < R && T < B;
704     }
705 
706 public:
707     /**
708      *  Return true if this rectangle is not empty, and the specified sides of
709      *  a rectangle are not empty, and they intersect.
710      */
intersectsSkRect711     bool intersects(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom) const {
712         return Intersects(fLeft, fTop, fRight, fBottom, left, top, right, bottom);
713     }
714 
intersectsSkRect715     bool intersects(const SkRect& r) const {
716         return Intersects(fLeft, fTop, fRight, fBottom,
717                           r.fLeft, r.fTop, r.fRight, r.fBottom);
718     }
719 
720     /**
721      *  Return true if rectangles a and b are not empty and intersect.
722      */
IntersectsSkRect723     static bool Intersects(const SkRect& a, const SkRect& b) {
724         return Intersects(a.fLeft, a.fTop, a.fRight, a.fBottom,
725                           b.fLeft, b.fTop, b.fRight, b.fBottom);
726     }
727 
728     /**
729      *  Update this rectangle to enclose itself and the specified rectangle.
730      *  If this rectangle is empty, just set it to the specified rectangle.
731      *  If the specified rectangle is empty, do nothing.
732      */
733     void join(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom);
734 
735     /** Update this rectangle to enclose itself and the specified rectangle.
736         If this rectangle is empty, just set it to the specified rectangle. If the specified
737         rectangle is empty, do nothing.
738     */
joinSkRect739     void join(const SkRect& r) {
740         this->join(r.fLeft, r.fTop, r.fRight, r.fBottom);
741     }
742 
joinNonEmptyArgSkRect743     void joinNonEmptyArg(const SkRect& r) {
744         SkASSERT(!r.isEmpty());
745         // if we are empty, just assign
746         if (fLeft >= fRight || fTop >= fBottom) {
747             *this = r;
748         } else {
749             this->joinPossiblyEmptyRect(r);
750         }
751     }
752 
753     /**
754      * Joins the rectangle with another without checking if either are empty (may produce unexpected
755      * results if either rect is inverted).
756      */
joinPossiblyEmptyRectSkRect757     void joinPossiblyEmptyRect(const SkRect& r) {
758         fLeft   = SkMinScalar(fLeft, r.left());
759         fTop    = SkMinScalar(fTop, r.top());
760         fRight  = SkMaxScalar(fRight, r.right());
761         fBottom = SkMaxScalar(fBottom, r.bottom());
762     }
763 
764     /**
765      *  Grow the rect to include the specified (x,y). After this call, the
766      *  following will be true: fLeft <= x <= fRight && fTop <= y <= fBottom.
767      *
768      *  This is close, but not quite the same contract as contains(), since
769      *  contains() treats the left and top different from the right and bottom.
770      *  contains(x,y) -> fLeft <= x < fRight && fTop <= y < fBottom. Also note
771      *  that contains(x,y) always returns false if the rect is empty.
772      */
growToIncludeSkRect773     void growToInclude(SkScalar x, SkScalar y) {
774         fLeft  = SkMinScalar(x, fLeft);
775         fRight = SkMaxScalar(x, fRight);
776         fTop    = SkMinScalar(y, fTop);
777         fBottom = SkMaxScalar(y, fBottom);
778     }
779 
780     /** Bulk version of growToInclude */
growToIncludeSkRect781     void growToInclude(const SkPoint pts[], int count) {
782         this->growToInclude(pts, sizeof(SkPoint), count);
783     }
784 
785     /** Bulk version of growToInclude with stride. */
growToIncludeSkRect786     void growToInclude(const SkPoint pts[], size_t stride, int count) {
787         SkASSERT(count >= 0);
788         SkASSERT(stride >= sizeof(SkPoint));
789         const SkPoint* end = (const SkPoint*)((intptr_t)pts + count * stride);
790         for (; pts < end; pts = (const SkPoint*)((intptr_t)pts + stride)) {
791             this->growToInclude(pts->fX, pts->fY);
792         }
793     }
794 
795     /**
796      *  Return true if this rectangle contains r, and if both rectangles are
797      *  not empty.
798      */
containsSkRect799     bool contains(const SkRect& r) const {
800         // todo: can we eliminate the this->isEmpty check?
801         return  !r.isEmpty() && !this->isEmpty() &&
802                 fLeft <= r.fLeft && fTop <= r.fTop &&
803                 fRight >= r.fRight && fBottom >= r.fBottom;
804     }
805 
806     /**
807      * Returns true if the specified rectangle r is inside or equal to this rectangle.
808      */
containsSkRect809     bool contains(const SkIRect& r) const {
810         // todo: can we eliminate the this->isEmpty check?
811         return  !r.isEmpty() && !this->isEmpty() &&
812                 fLeft <= SkIntToScalar(r.fLeft) && fTop <= SkIntToScalar(r.fTop) &&
813                 fRight >= SkIntToScalar(r.fRight) && fBottom >= SkIntToScalar(r.fBottom);
814     }
815 
816     /**
817      *  Set the dst rectangle by rounding this rectangle's coordinates to their
818      *  nearest integer values using SkScalarRoundToInt.
819      */
roundSkRect820     void round(SkIRect* dst) const {
821         SkASSERT(dst);
822         dst->set(SkScalarRoundToInt(fLeft), SkScalarRoundToInt(fTop),
823                  SkScalarRoundToInt(fRight), SkScalarRoundToInt(fBottom));
824     }
825 
826     /**
827      *  Set the dst rectangle by rounding "out" this rectangle, choosing the
828      *  SkScalarFloor of top and left, and the SkScalarCeil of right and bottom.
829      */
roundOutSkRect830     void roundOut(SkIRect* dst) const {
831         SkASSERT(dst);
832         dst->set(SkScalarFloorToInt(fLeft), SkScalarFloorToInt(fTop),
833                  SkScalarCeilToInt(fRight), SkScalarCeilToInt(fBottom));
834     }
835 
836     /**
837      *  Set the dst rectangle by rounding "out" this rectangle, choosing the
838      *  SkScalarFloorToScalar of top and left, and the SkScalarCeilToScalar of right and bottom.
839      *
840      *  It is safe for this == dst
841      */
roundOutSkRect842     void roundOut(SkRect* dst) const {
843         dst->set(SkScalarFloorToScalar(fLeft),
844                  SkScalarFloorToScalar(fTop),
845                  SkScalarCeilToScalar(fRight),
846                  SkScalarCeilToScalar(fBottom));
847     }
848 
849     /**
850      *  Set the dst rectangle by rounding "in" this rectangle, choosing the
851      *  ceil of top and left, and the floor of right and bottom. This does *not*
852      *  call sort(), so it is possible that the resulting rect is inverted...
853      *  e.g. left >= right or top >= bottom. Call isEmpty() to detect that.
854      */
roundInSkRect855     void roundIn(SkIRect* dst) const {
856         SkASSERT(dst);
857         dst->set(SkScalarCeilToInt(fLeft), SkScalarCeilToInt(fTop),
858                  SkScalarFloorToInt(fRight), SkScalarFloorToInt(fBottom));
859     }
860 
861     //! Returns the result of calling round(&dst)
roundSkRect862     SkIRect round() const {
863         SkIRect ir;
864         this->round(&ir);
865         return ir;
866     }
867 
868     //! Returns the result of calling roundOut(&dst)
roundOutSkRect869     SkIRect roundOut() const {
870         SkIRect ir;
871         this->roundOut(&ir);
872         return ir;
873     }
874 
875     /**
876      *  Swap top/bottom or left/right if there are flipped (i.e. if width()
877      *  or height() would have returned a negative value.) This should be called
878      *  if the edges are computed separately, and may have crossed over each
879      *  other. When this returns, left <= right && top <= bottom
880      */
sortSkRect881     void sort() {
882         if (fLeft > fRight) {
883             SkTSwap<SkScalar>(fLeft, fRight);
884         }
885 
886         if (fTop > fBottom) {
887             SkTSwap<SkScalar>(fTop, fBottom);
888         }
889     }
890 
891     /**
892      *  cast-safe way to treat the rect as an array of (4) SkScalars.
893      */
asScalarsSkRect894     const SkScalar* asScalars() const { return &fLeft; }
895 
896     void dump(bool asHex) const;
dumpSkRect897     void dump() const { this->dump(false); }
dumpHexSkRect898     void dumpHex() const { this->dump(true); }
899 };
900 
contains(const SkRect & r)901 inline bool SkIRect::contains(const SkRect& r) const {
902     return  !r.isEmpty() && !this->isEmpty() &&     // check for empties
903             (SkScalar)fLeft <= r.fLeft && (SkScalar)fTop <= r.fTop &&
904             (SkScalar)fRight >= r.fRight && (SkScalar)fBottom >= r.fBottom;
905 }
906 
907 #endif
908