SkIRect holds four 32 bit integer coordinates describing the upper and lower bounds of a rectangle. SkIRect may be created from outer bounds or from position, width, and height. SkIRect describes an area; if its right is less than or equal to its left, or if its bottom is less than or equal to its top, it is considered empty.
| topics | description |
|---|
| description | function |
|---|---|
| bool operator!=(const SkIRect& a, const SkIRect& b) | Returns true if members are unequal. |
| bool operator==(const SkIRect& a, const SkIRect& b) | Returns true if members are equal. |
| description | function |
|---|---|
| EmptyIRect | Returns immutable bounds of (0, 0, 0, 0). |
| Intersects | Returns true if areas overlap. |
| IntersectsNoEmptyCheck | Returns true if areas overlap. Skips empty check. |
| MakeEmpty | Returns bounds of (0, 0, 0, 0). |
| MakeLTRB | Constructs from int left, top, right, bottom. |
| MakeSize | Constructs from ISize returning (0, 0, width, height). |
| MakeWH | Constructs from int input returning (0, 0, width, height). |
| MakeXYWH | Constructs from int input returning (x, y, width, height). |
| bottom | Returns larger bounds in y, if sorted. |
| centerX | Returns midpoint in x. |
| centerY | Returns midpoint in y. |
| contains | Returns true if points are equal or inside. |
| containsNoEmptyCheck | Returns true if points are equal or inside. Skips empty check. |
| height | Returns span in y. |
| height64 | Returns span in y as int64_t. |
| inset | Moves the sides symmetrically about the center. |
| intersect | Sets to shared area; returns true if not empty. |
| intersectNoEmptyCheck | Sets to shared area; returns true if not empty. Skips empty check. |
| is16Bit | Returns true if members fit in 16-bit word. |
| isEmpty | Returns true if width or height are zero or negative or they exceed int32_t. |
| isEmpty64 | Returns true if width or height are zero or negative. |
| join | Sets to union of bounds. |
| left | Returns smaller bounds in x, if sorted. |
| makeInset | Constructs from sides moved symmetrically about the center. |
| makeOffset | Constructs from translated sides. |
| makeOutset | Constructs from sides moved symmetrically about the center. |
| makeSorted | Constructs, ordering sides from smaller to larger. |
| offset | Translates sides without changing width and height. |
| offsetTo | Translates to (x, y) without changing width and height. |
| outset | Moves the sides symmetrically about the center. |
| quickReject | Returns true if rectangles do not intersect. |
| right | Returns larger bounds in x, if sorted. |
| set | Sets to (left, top, right, bottom). |
| setEmpty | Sets to (0, 0, 0, 0). |
| setLTRB | Sets to SkScalar input (left, top, right, bottom). |
| setXYWH | Sets to (x, y, width, height). |
| size | Returns ISize (width, height). |
| sort | Orders sides from smaller to larger. |
| top | Returns smaller bounds in y, if sorted. |
| width | Returns span in x. |
| width64 | Returns span in y as int64_t. |
| x | Returns bounds left. |
| y | Returns bounds top. |
int32_t fLeft
May contain any value. The smaller of the horizontal values when sorted. When equal to or greater than fRight, IRect is empty.
int32_t fTop
May contain any value. The smaller of the horizontal values when sorted. When equal to or greater than fBottom, IRect is empty.
int32_t fRight
May contain any value. The larger of the vertical values when sorted. When equal to or less than fLeft, IRect is empty.
int32_t fBottom
May contain any value. The larger of the vertical values when sorted. When equal to or less than fTop, IRect is empty.
Returns constructed IRect set to (0, 0, 0, 0). Many other rectangles are empty; if left is equal to or greater than right, or if top is equal to or greater than bottom. Setting all members to zero is a convenience, but does not designate a special empty rectangle.
bounds (0, 0, 0, 0)
MakeEmpty isEmpty: true offset rect isEmpty: true inset rect isEmpty: true outset rect isEmpty: false
EmptyIRect isEmpty setEmpty SkRect::MakeEmpty
Returns constructed IRect set to (0, 0, w, h). Does not validate input; w or h may be negative.
bounds (0, 0, w, h)
all equal
MakeSize MakeXYWH SkRect::MakeWH SkRect::MakeIWH
Returns constructed IRect set to (0, 0, size.width, size.height). Does not validate input; size.width or size.height may be negative.
bounds (0, 0, size.width, size.height)
round width: 26 height: 36 floor width: 25 height: 35
MakeWH MakeXYWH SkRect::Make SkRect::MakeIWH
Returns constructed IRect set to (l, t, r, b). Does not sort input; Rect may result in fLeft greater than fRight, or fTop greater than fBottom.
bounds (l, t, r, b)
rect: 5, 35, 15, 25 isEmpty: true rect: 5, 25, 15, 35 isEmpty: false
MakeXYWH SkRect::MakeLTRB
Returns constructed IRect set to: (x, y, x + w, y + h). Does not validate input; w or h may be negative.
bounds at (x, y) with width w and height h
rect: 5, 35, -10, 60 isEmpty: true rect: -10, 35, 5, 60 isEmpty: false
MakeLTRB SkRect::MakeXYWH
Returns left edge of IRect, if sorted. Call sort to reverse fLeft and fRight if needed.
fLeft
unsorted.fLeft: 15 unsorted.left(): 15 sorted.fLeft: 10 sorted.left(): 10
fLeft x SkRect::left()
Returns top edge of IRect, if sorted. Call isEmpty to see if IRect may be invalid, and sort to reverse fTop and fBottom if needed.
fTop
unsorted.fTop: 25 unsorted.top(): 25 sorted.fTop: 5 sorted.top(): 5
fTop y SkRect::top()
Returns right edge of IRect, if sorted. Call sort to reverse fLeft and fRight if needed.
fRight
unsorted.fRight: 10 unsorted.right(): 10 sorted.fRight: 15 sorted.right(): 15
fRight SkRect::right()
Returns bottom edge of IRect, if sorted. Call isEmpty to see if IRect may be invalid, and sort to reverse fTop and fBottom if needed.
fBottom
unsorted.fBottom: 5 unsorted.bottom(): 5 sorted.fBottom: 25 sorted.bottom(): 25
fBottom SkRect::bottom()
Returns left edge of IRect, if sorted. Call isEmpty to see if IRect may be invalid, and sort to reverse fLeft and fRight if needed.
fLeft
unsorted.fLeft: 15 unsorted.x(): 15 sorted.fLeft: 10 sorted.x(): 10
fLeft left y SkRect::x()
Returns top edge of IRect, if sorted. Call isEmpty to see if IRect may be invalid, and sort to reverse fTop and fBottom if needed.
fTop
unsorted.fTop: 25 unsorted.y(): 25 sorted.fTop: 5 sorted.y(): 5
fTop top x SkRect::y()
Returns span on the x-axis. This does not check if IRect is sorted, or if result fits in 32-bit signed integer; result may be negative.
fRight minus fLeft
unsorted width: -5 large width: -5
height width64 height64 SkRect::width()
Returns span on the x-axis. This does not check if IRect is sorted, so the result may be negative. This is safer than calling width since width might overflow in its calculation.
fRight minus fLeft cast to int64_t
SkIRect large = { -2147483647, 1, 2147483644, 2 };
width: -5 width64: 4294967291
width height height64 SkRect::width()
Returns span on the y-axis. This does not check if IRect is sorted, or if result fits in 32-bit signed integer; result may be negative.
fBottom minus fTop
unsorted height: -5 large height: -5
width SkRect::height()
Returns span on the y-axis. This does not check if IRect is sorted, so the result may be negative. This is safer than calling height since height might overflow in its calculation.
fBottom minus fTop cast to int64_t
SkIRect large = { 1, -2147483647, 2, 2147483644 };
height: -5 height64: 4294967291
width height width64 SkRect::height()
Returns spans on the x-axis and y-axis. This does not check if IRect is sorted, or if result fits in 32-bit signed integer; result may be negative.
ISize (width, height)
original rect: 20, 30, 40, 50 size: 20, 20 offset rect: 40, 50, 60, 70 size: 20, 20 outset rect: 20, 30, 80, 90 size: 60, 60
height width MakeSize
Returns average of left edge and right edge. Result does not change if Rect is sorted. Result may be incorrect if Rect is far from the origin.
Result is rounded down.
midpoint in x
left: 20 right: 41 centerX: 30 div2: 30 left: -20 right: -41 centerX: -31 div2: -30 left: -10 right: 11 centerX: 0 div2: 0
centerY SkRect::centerX
Returns average of top edge and bottom edge. Result does not change if Rect is sorted. Result may be incorrect if Rect is far from the origin.
Result is rounded down.
midpoint in y
left: 1073741824 right: 1073741826 centerX: -1073741823 safe mid x: 1073741825
centerX SkRect::centerY
Returns true if width or height .
true if width or height are zero or negative
rect: {20, 40, 10, 50} is empty
sorted: {10, 40, 20, 50} is not empty
rect: {20, 40, 20, 50} is empty
sorted: {20, 40, 20, 50} is empty
EmptyIRect MakeEmpty sort SkRect::isEmpty
Returns true if fLeft is equal to or greater than fRight, or if fTop is equal to or greater than fBottom. Call sort to reverse rectangles with negative width64 or height64.
true if width64 or height64 are zero or negative
SkIRect tests[] = {{20, 40, 10, 50}, {20, 40, 20, 50}}; for (auto rect : tests) {
rect: {20, 40, 10, 50} is empty
sorted: {10, 40, 20, 50} is not empty
rect: {20, 40, 20, 50} is empty
sorted: {20, 40, 20, 50} is empty
EmptyIRect MakeEmpty sort SkRect::isEmpty
Returns true if all members in a: fLeft, fTop, fRight, and fBottom; are identical to corresponding members in b.
true if members are equal
test == sorted
operator!=(const SkIRect& a, const SkIRect& b)
Returns true if any member in a: fLeft, fTop, fRight, and fBottom; is not identical to the corresponding member in b.
true if members are not equal
test != sorted
operator==(const SkIRect& a, const SkIRect& b)
Returns true if all members: fLeft, fTop, fRight, and fBottom; values are equal to or larger than -32768 and equal to or smaller than 32767.
true if members fit in 16-bit word
{-32768, -32768, 32767, 32767} fits in 16 bits
{-32768, -32768, 32768, 32768} does not fit in 16 bits
SkTFitsIn
Sets IRect to (0, 0, 0, 0).
Many other rectangles are empty; if left is equal to or greater than right, or if top is equal to or greater than bottom. Setting all members to zero is a convenience, but does not designate a special empty rectangle.
rect: {3, 4, 1, 2} is empty
rect: {0, 0, 0, 0} is empty
MakeEmpty SkRect::setEmpty
Sets IRect to (left, top, right, bottom). left and right are not sorted; left is not necessarily less than right. top and bottom are not sorted; top is not necessarily less than bottom.
rect1: {3, 4, 1, 2}
rect2: {3, 4, 1, 2}
setLTRB setXYWH SkRect::set
Sets IRect to (left, top, right, bottom). left and right are not sorted; left is not necessarily less than right. top and bottom are not sorted; top is not necessarily less than bottom.
rect1: {3, 4, 1, 2}
rect2: {3, 4, 1, 2}
set setXYWH SkRect::setLTRB
Sets IRect to: (x, y, x + width, y + height). Does not validate input; width or height may be negative.
rect: 5, 35, -10, 60 isEmpty: true rect: -10, 35, 5, 60 isEmpty: false
MakeXYWH setLTRB set SkRect::setXYWH
Returns IRect offset by (dx, dy).
If dx is negative, IRect returned is moved to the left. If dx is positive, IRect returned is moved to the right. If dy is negative, IRect returned is moved upward. If dy is positive, IRect returned is moved downward.
Rect offset in x or y, with original width and height
rect: 10, 50, 20, 60 isEmpty: false rect: 25, 82, 35, 92 isEmpty: false
offset makeInset makeOutset SkRect::makeOffset
Returns IRect, inset by (dx, dy).
If dx is negative, IRect returned is wider. If dx is positive, IRect returned is narrower. If dy is negative, IRect returned is taller. If dy is positive, IRect returned is shorter.
Rect inset symmetrically left and right, top and bottom
rect: 10, 50, 20, 60 isEmpty: false rect: 25, 82, 5, 28 isEmpty: true
inset makeOffset makeOutset SkRect::makeInset
Returns IRect, outset by (dx, dy).
If dx is negative, IRect returned is narrower. If dx is positive, IRect returned is wider. If dy is negative, IRect returned is shorter. If dy is positive, IRect returned is taller.
Rect outset symmetrically left and right, top and bottom
rect: 10, 50, 20, 60 isEmpty: false rect: -5, 18, 35, 92 isEmpty: false
outset makeOffset makeInset SkRect::makeOutset
Offsets IRect by adding dx to fLeft, fRight; and by adding dy to fTop, fBottom.
If dx is negative, moves IRect returned to the left. If dx is positive, moves IRect returned to the right. If dy is negative, moves IRect returned upward. If dy is positive, moves IRect returned downward.
rect: 15, 27, 55, 86
offsetTo makeOffset SkRect::offset
Offsets IRect by adding delta.fX to fLeft, fRight; and by adding delta.fY to fTop, fBottom.
If delta.fX is negative, moves IRect returned to the left. If delta.fX is positive, moves IRect returned to the right. If delta.fY is negative, moves IRect returned upward. If delta.fY is positive, moves IRect returned downward.
rect: 15, 27, 55, 86
offsetTo makeOffset SkRect::offset
Offsets IRect so that fLeft equals newX, and fTop equals newY. width and height are unchanged.
rect: 15, 27, 55, 86
offset makeOffset setXYWH SkRect::offsetTo
Insets IRect by (dx,dy).
If dx is positive, makes IRect narrower. If dx is negative, makes IRect wider. If dy is positive, makes IRect shorter. If dy is negative, makes IRect taller.
rect: 15, 27, 45, 60
outset makeInset SkRect::inset
Outsets IRect by (dx, dy).
If dx is positive, makes Rect wider. If dx is negative, makes Rect narrower. If dy is positive, makes Rect taller. If dy is negative, makes Rect shorter.
rect: 5, 1, 55, 86
inset makeOutset SkRect::outset
Constructs IRect (l, t, r, b) and returns true if constructed IRect does not intersect IRect. Does not check to see if construction or IRect is empty.
Is implemented with short circuit logic so that true can be returned after a single compare.
true if construction and IRect have no area in common
rect (7, 11, 13, 17) test(13, 11, 15, 17) quickReject true; intersects false rect (7, 11, 13, 17) test(7, 7, 13, 11) quickReject true; intersects false rect (7, 11, 13, 17) test(12, 16, 14, 18) quickReject false; intersects true
Intersects
Returns true if: fLeft <= x < fRight && fTop <= y < fBottom.
Returns false if Rect is empty.
Considers input to describe constructed IRect: (x, y, x + 1, y + 1)and returns true if constructed area is completely enclosed by IRect area.
true if (x, y) is inside IRect
rect: (30, 50, 40, 60) contains (30, 50) rect: (30, 50, 40, 60) does not contain (40, 50) rect: (30, 50, 40, 60) does not contain (30, 60)
containsNoEmptyCheck SkRect::contains
Constructs Rect to intersect from (left, top, right, bottom). Does not sort construction.
Returns true if Rect contains construction. Returns false if Rect is empty or construction is empty.
true if all sides of IRect are outside construction
rect: (30, 50, 40, 60) contains (30, 50, 31, 51) rect: (30, 50, 40, 60) does not contain (39, 49, 40, 50) rect: (30, 50, 40, 60) does not contain (29, 59, 30, 60)
containsNoEmptyCheck SkRect::contains
Returns true if Rect contains r. Returns false if Rect is empty or r is empty.
Rect contains r when Rect area completely includes r area.
true if all sides of IRect are outside r
rect: (30, 50, 40, 60) contains (30, 50, 31, 51) rect: (30, 50, 40, 60) does not contain (39, 49, 40, 50) rect: (30, 50, 40, 60) does not contain (29, 59, 30, 60)
containsNoEmptyCheck SkRect::contains
Returns true if Rect contains r. Returns false if Rect is empty or r is empty.
Rect contains r when Rect area completely includes r area.
true if all sides of IRect are outside r
rect: (30, 50, 40, 60) contains (30, 50, 31, 51) rect: (30, 50, 40, 60) does not contain (39, 49, 40, 50) rect: (30, 50, 40, 60) does not contain (29, 59, 30, 60)
containsNoEmptyCheck SkRect::contains
Constructs IRect from (left, top, right, bottom). Does not sort construction.
Returns true if Rect contains construction. Asserts if IRect is empty or construction is empty, and if SK_DEBUG is defined.
Return is undefined if Rect is empty or construction is empty.
true if all sides of IRect are outside construction
rect: (30, 50, 40, 60) contains (30, 50, 31, 51) rect: (30, 50, 40, 60) does not contain (39, 49, 40, 50) rect: (30, 50, 40, 60) does not contain (29, 59, 30, 60)
contains SkRect::contains
Returns true if Rect contains construction. Asserts if IRect is empty or construction is empty, and if SK_DEBUG is defined.
Return is undefined if Rect is empty or construction is empty.
true if all sides of IRect are outside r
rect: (30, 50, 40, 60) contains (30, 50, 31, 51) rect: (30, 50, 40, 60) does not contain (39, 49, 40, 50) rect: (30, 50, 40, 60) does not contain (29, 59, 30, 60)
contains SkRect::contains
IRects intersect when they enclose a common area. To intersect, each of the pair must describe area; fLeft is less than fRight, and fTop is less than fBottom; empty() returns false. The intersection of IRect pair can be described by: (max(a.fLeft, b.fLeft), max(a.fTop, b.fTop), min(a.fRight, b.fRight), min(a.fBottom, b.fBottom))The intersection is only meaningful if the resulting IRect is not empty and describes an area: fLeft is less than fRight, and fTop is less than fBottom.
Returns true if IRect intersects r, and sets IRect to intersection. Returns false if IRect does not intersect r, and leaves IRect unchanged.
Returns false if either r or IRect is empty, leaving IRect unchanged.
true if r and Rect have area in common
intersection: 30, 60, 50, 80
Intersects intersectNoEmptyCheck join SkRect::intersect
Returns true if a intersects b, and sets IRect to intersection. Returns false if a does not intersect b, and leaves IRect unchanged.
Returns false if either a or b is empty, leaving IRect unchanged.
true if a and b have area in common
intersection: 30, 60, 50, 80
Intersects intersectNoEmptyCheck join SkRect::intersect
Returns true if a intersects b, and sets IRect to intersection. Returns false if a does not intersect b, and leaves IRect unchanged.
Asserts if either a or b is empty, and if SK_DEBUG is defined.
true if a and b have area in common
intersection: 30, 60, 50, 80
Intersects intersect join SkRect::intersect
Constructs IRect to intersect from (left, top, right, bottom). Does not sort construction.
Returns true if IRect intersects construction, and sets IRect to intersection. Returns false if IRect does not intersect construction, and leaves IRect unchanged.
Returns false if either construction or IRect is empty, leaving IRect unchanged.
true if construction and IRect have area in common
intersection: 30, 60, 50, 80
intersectNoEmptyCheck Intersects join SkRect::intersect
Returns true if a intersects b. Returns false if either a or b is empty, or do not intersect.
true if a and b have area in common
intersection
IntersectsNoEmptyCheck intersect SkRect::intersect
Returns true if a intersects b. Asserts if either a or b is empty, and if SK_DEBUG is defined.
true if a and b have area in common
intersection
Intersects intersect SkRect::intersect
Constructs Rect to intersect from (left, top, right, bottom). Does not sort construction.
Sets Rect to the union of itself and the construction.
Has no effect if construction is empty. Otherwise, if Rect is empty, sets Rect to construction.
join: 10, 20, 55, 65
set SkRect::join
Sets Rect to the union of itself and r.
Has no effect if r is empty. Otherwise, if Rect is empty, sets Rect to r.
join: 10, 20, 55, 65
set SkRect::join
Swaps fLeft and fRight if fLeft is greater than fRight; and swaps fTop and fBottom if fTop is greater than fBottom. Result may be empty, and width and height will be zero or positive.
rect: 30, 50, 20, 10 sorted: 20, 10, 30, 50
makeSorted SkRect::sort
Returns Rect with fLeft and fRight swapped if fLeft is greater than fRight; and with fTop and fBottom swapped if fTop is greater than fBottom. Result may be empty; and width and height will be zero or positive.
sorted IRect
rect: 30, 50, 20, 10 sorted: 20, 10, 30, 50
sort SkRect::makeSorted
Returns a reference to immutable empty IRect, set to (0, 0, 0, 0).
global IRect set to all zeroes
rect: 0, 0, 0, 0
MakeEmpty
Returns constructed SkIRect setting left and top to most negative value, and setting right and bottom to most positive value.
bounds (SK MinS32, SK MinS32, SK MaxS32, SK MaxS32)