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All functions should have descriptions, examples, cross-references. References and spelling have been checked. More work to do creating and organizing topics. Docs-Preview: https://skia.org/?cl=56140 Tbr: caryclark@google.com Bug: skia:6898 Change-Id: I9d1e55d04ab64874c33cac8b91534aa192c2f545 Reviewed-on: https://skia-review.googlesource.com/56140 Reviewed-by: Cary Clark <caryclark@skia.org> Commit-Queue: Cary Clark <caryclark@skia.org>
102 KiB
SkRect Reference
Rect
Struct SkRect
SkRect holds four SkScalar coordinates describing the upper and lower bounds of a rectangle. SkRect may be created from outer bounds or from position, width, and height. SkRect 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.
SkRect can be constructed from int values to avoid compiler warnings that integer input cannot convert to SkScalar without loss of precision.
Overview
Subtopics
| topics | description |
|---|
Operators
| description | function |
|---|---|
| friend bool operator!=(const SkRect& a, const SkRect& b) | Returns true if member bits are unequal. |
| friend bool operator==(const SkRect& a, const SkRect& b) | Returns true if member bits are equal. |
Member Functions
| description | function |
|---|---|
| Intersects | Returns true if areas overlap. |
| Make | Constructs from ISize returning (0, 0, width, height). |
| MakeEmpty | Constructs from bounds of (0, 0, 0, 0). |
| MakeFromIRect | Deprecated. |
| MakeIWH | Constructs from int input returning (0, 0, width, height). |
| MakeLTRB | Constructs from SkScalar left, top, right, bottom. |
| MakeLargest | Constructs (SK ScalarMin, SK ScalarMin, SK ScalarMax, SK ScalarMax). |
| MakeSize | Constructs from Size returning (0, 0, width, height). |
| MakeWH | Constructs from SkScalar input returning (0, 0, width, height). |
| MakeXYWH | Constructs from SkScalar input returning (x, y, width, height). |
| asScalars | Returns pointer to members as array. |
| 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. |
| dump | Sends text representation using floats to standard output. |
| dumpHex | Sends text representation using hexadecimal to standard output. |
| growToInclude | Sets to union of bounds and one or more Points. |
| height | Returns span in y. |
| inset | Moves the sides symmetrically about the center. |
| intersect | Sets to shared area; returns true if not empty. |
| intersects | Returns true if areas overlap. |
| isEmpty | Returns true if width or height are zero or negative. |
| isFinite | Returns true if no member is infinite or NaN. |
| isLargest | Returns equal to (SK ScalarMin, SK ScalarMin, SK ScalarMax, SK ScalarMax). |
| isSorted | Returns true if width or height are zero or positive. |
| iset | Sets to int input (left, top, right, bottom). |
| isetWH | Sets to int input (0, 0, width, height). |
| join | Sets to union of bounds. |
| joinNonEmptyArg | Sets to union of bounds, asserting that argument is not empty. |
| joinPossiblyEmptyRect | Sets to union of bounds. Skips empty check for both. |
| 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. |
| right | Returns larger bounds in x, if sorted. |
| round | Sets members to nearest integer value. |
| roundIn | Sets members to nearest integer value towards opposite. |
| roundOut | Sets members to nearest integer value away from opposite. |
| set | Sets to SkScalar input (left, top, right, bottom) and others. |
| setBounds | Sets to upper and lower limits of Point array. |
| setBoundsCheck | Sets to upper and lower limits of Point array. |
| setEmpty | Sets to (0, 0, 0, 0). |
| setLTRB | Sets to SkScalar input (left, top, right, bottom). |
| setLargest | Sets to (SK ScalarMin, SK ScalarMin, SK ScalarMax, SK ScalarMax). |
| setLargestInverted | Sets to (SK ScalarMax, SK ScalarMax, SK ScalarMin, SK ScalarMin). |
| setWH | Sets to SkScalar input (0, 0, width, height). |
| setXYWH | Sets to SkScalar input (x, y, width, height). |
| sort | Orders sides from smaller to larger. |
| toQuad | Returns four corners as Point. |
| top | Returns smaller bounds in y, if sorted. |
| width | Returns span in x. |
| x | Returns bounds left. |
| y | Returns bounds top. |
May contain any value, including infinities and NaN. The smaller of the horizontal values when sorted. When equal to or greater than fRight, Rect is empty.
May contain any value, including infinities and NaN. The smaller of the vertical values when sorted. When equal to or greater than fBottom, Rect is empty.
May contain any value, including infinities and NaN. The larger of the horizontal values when sorted. When equal to or less than fLeft, Rect is empty.
May contain any value, including infinities and NaN. The larger of the vertical values when sorted. When equal to or less than fTop, Rect is empty.
MakeEmpty
static constexpr SkRect SK_WARN_UNUSED_RESULT MakeEmpty()
Returns constructed Rect 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.
Return Value
bounds (0, 0, 0, 0)
Example
Example Output
MakeEmpty isEmpty: true
offset rect isEmpty: true
inset rect isEmpty: true
outset rect isEmpty: false
See Also
isEmpty setEmpty setLargestInverted SkIRect::MakeEmpty
MakeLargest
static SkRect SK_WARN_UNUSED_RESULT MakeLargest()
Returns constructed Rect setting left and top to most negative finite value, and setting right and bottom to most positive finite value.
Return Value
bounds (SK ScalarMin, SK ScalarMin, SK ScalarMax, SK ScalarMax)
Example
Example Output
MakeLargest isLargest: true
MakeLargest isFinite: true
outset a little isLargest: true
outset a little isFinite: true
outset a little more isLargest: false
outset a little more isFinite: false
See Also
isLargest setLargest SkIRect::MakeLargest
MakeWH
static SkRect SK_WARN_UNUSED_RESULT MakeWH(SkScalar w, SkScalar h)
Returns constructed Rect set to SkScalar values (0, 0, w, h). Does not validate input; w or h may be negative.
Passing integer values may generate a compiler warning since Rect cannot represent 32-bit integers exactly. Use SkIRect for an exact integer rectangle.
Parameters
w | SkScalar width of constructed Rect |
h | SkScalar height of constructed Rect |
Return Value
Example
Example Output
all equal
See Also
MakeSize MakeXYWH MakeIWH setWH SkIRect::MakeWH
MakeIWH
static SkRect SK_WARN_UNUSED_RESULT MakeIWH(int w, int h)
Returns constructed Rect set to integer values (0, 0, w, h). Does not validate input; w or h may be negative.
Use to avoid a compiler warning that input may lose precision when stored. Use SkIRect for an exact integer rectangle.
Parameters
w | integer width of constructed Rect |
h | integer height of constructed Rect |
Return Value
Example
Example Output
i_rect width: 25 f_rect width:25
i_rect width: 125000111 f_rect width:125000112
See Also
MakeXYWH MakeWH isetWH SkIRect::MakeWH
MakeSize
static SkRect SK_WARN_UNUSED_RESULT MakeSize(const SkSize& size)
Returns constructed Rect set to (0, 0, size.width, size.height). Does not validate input; size.width or size.height may be negative.
Parameters
size | SkScalar values for Rect width and height |
Return Value
bounds (0, 0, size.width, size.height)
Example
Example Output
rect width: 25.5 height: 35.5
floor width: 25 height: 35
See Also
MakeWH MakeXYWH MakeIWH setWH SkIRect::MakeWH
MakeLTRB
static constexpr SkRect SK_WARN_UNUSED_RESULT MakeLTRB(SkScalar l, SkScalar t,
SkScalar r, SkScalar b)
Returns constructed Rect set to (l, t, r, b). Does not sort input; Rect may result in fLeft greater than fRight, or fTop greater than fBottom.
Parameters
l | SkScalar stored in fLeft |
t | SkScalar stored in fTop |
r | SkScalar stored in fRight |
b | SkScalar stored in fBottom |
Return Value
Example
Example Output
rect: 5, 35, 15, 25 isEmpty: true
rect: 5, 25, 15, 35 isEmpty: false
See Also
MakeXYWH
static SkRect SK_WARN_UNUSED_RESULT MakeXYWH(SkScalar x, SkScalar y, SkScalar w,
SkScalar h)
Returns constructed Rect set to(x, y, x + w, y + h). Does not validate input; w or h may be negative.
Parameters
x | stored in fLeft |
y | stored in fTop |
w | added to x and stored in fRight |
h | added to y and stored in fBottom |
Return Value
Example
Example Output
rect: 5, 35, -10, 60 isEmpty: true
rect: -10, 35, 5, 60 isEmpty: false
See Also
MakeFromIRect
static SkRect SK_WARN_UNUSED_RESULT MakeFromIRect(const SkIRect& irect)
Deprecated.
Parameters
irect | integer rect |
Return Value
See Also
Make
static SkRect Make(const SkISize& size)
Returns constructed IRect set to (0, 0, size.width, size.height). Does not validate input; size.width or size.height may be negative.
Parameters
size | integer values for Rect width and height |
Return Value
bounds (0, 0, size.width, size.height)
Example
Example Output
rect1 == rect2
See Also
MakeWH MakeXYWH SkRect::MakeIWH SkIRect::MakeSize
static SkRect SK_WARN_UNUSED_RESULT Make(const SkIRect& irect)
Returns constructed IRect set to irect, promoting integers to Scalar. Does not validate input; fLeft may be greater than fRight, fTop may be greater than fBottom.
Parameters
irect | integer unsorted bounds |
Return Value
irect members converted to SkScalar
Example
See Also
isEmpty
bool isEmpty() const
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 width or height.
Return Value
true if width or height are zero or negative
Example
Example Output
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
See Also
MakeEmpty sort SkIRect::isEmpty
isSorted
bool isSorted() const
Returns true if fLeft is equal to or less than fRight, or if fTop is equal to or less than fBottom. Call sort to reverse rectangles with negative width or height.
Return Value
true if width or height are zero or positive
Example
Example Output
rect: {20, 40, 10, 50} is not sorted
sorted: {10, 40, 20, 50} is sorted
rect: {20, 40, 20, 50} is sorted
sorted: {20, 40, 20, 50} is sorted
See Also
isLargest
bool isLargest() const
Returns true if Rect encloses largest possible area.
Return Value
true if equal to (SK ScalarMin, SK ScalarMin, SK ScalarMax, SK ScalarMax)
Example
Example Output
large is largest: true
large width inf
large is empty: false
large is sorted: true
large is finite: true
See Also
MakeLargest SkIRect::isLargest
isFinite
bool isFinite() const
Returns true if all values in the rectangle are finite: SK ScalarMin or larger, and SK ScalarMax or smaller.
Return Value
true if no member is infinite or NaN
Example
Example Output
largest is finite: true
large width inf
widest is finite: false
See Also
SkScalarIsFinite SkScalarIsNaN
x
SkScalar x() const
Returns left edge of Rect, if sorted. Call isSorted to see if Rect is valid. Call sort to reverse fLeft and fRight if needed.
Return Value
Example
Example Output
unsorted.fLeft: 15 unsorted.x(): 15
sorted.fLeft: 10 sorted.x(): 10
See Also
y
SkScalar y() const
Returns top edge of Rect, if sorted. Call isEmpty to see if Rect may be invalid, and sort to reverse fTop and fBottom if needed.
Return Value
Example
Example Output
unsorted.fTop: 25 unsorted.y(): 25
sorted.fTop: 5 sorted.y(): 5
See Also
left
SkScalar left() const
Returns left edge of Rect, if sorted. Call isSorted to see if Rect is valid. Call sort to reverse fLeft and fRight if needed.
Return Value
Example
Example Output
unsorted.fLeft: 15 unsorted.left(): 15
sorted.fLeft: 10 sorted.left(): 10
See Also
top
SkScalar top() const
Returns top edge of Rect, if sorted. Call isEmpty to see if Rect may be invalid, and sort to reverse fTop and fBottom if needed.
Return Value
Example
Example Output
unsorted.fTop: 25 unsorted.top(): 25
sorted.fTop: 5 sorted.top(): 5
See Also
right
SkScalar right() const
Returns right edge of Rect, if sorted. Call isSorted to see if Rect is valid. Call sort to reverse fLeft and fRight if needed.
Return Value
Example
Example Output
unsorted.fRight: 10 unsorted.right(): 10
sorted.fRight: 15 sorted.right(): 15
See Also
bottom
SkScalar bottom() const
Returns bottom edge of Rect, if sorted. Call isEmpty to see if Rect may be invalid, and sort to reverse fTop and fBottom if needed.
Return Value
Example
Example Output
unsorted.fBottom: 5 unsorted.bottom(): 5
sorted.fBottom: 25 sorted.bottom(): 25
See Also
width
SkScalar width() const
Returns span on the x-axis. This does not check if Rect is sorted, or if result fits in 32-bit float; result may be negative or infinity.
Return Value
Example
See Also
height
SkScalar height() const
Returns span on the y-axis. This does not check if IRect is sorted, or if result fits in 32-bit float; result may be negative or infinity.
Return Value
Example
See Also
centerX
SkScalar centerX() const
Returns average of left edge and right edge. Result does not change if Rect is sorted. Result may overflow to infinity if Rect is far from the origin.
Return Value
midpoint in x
Example
Example Output
left: 20 right: 41 centerX: 30.5
left: 20 right: 41 centerX: 30.5
left: -20 right: -41 centerX: -30.5
left: -41 right: -20 centerX: -30.5
See Also
centerY
SkScalar centerY() const
Returns average of top edge and bottom edge. Result does not change if Rect is sorted. Result may overflow to infinity if Rect is far from the origin.
Return Value
midpoint in y
Example
Example Output
left: 2e+38 right: 3e+38 centerX: inf safe mid x: 2.5e+38
See Also
operator==
friend bool operator==(const SkRect& a, const SkRect& b)
Returns true if all members in a: fLeft, fTop, fRight, and fBottom; are
equal to the corresponding members in b.
a and b are not equal if either contain NaN. a and b are equal if members contain zeroes width different signs.
Parameters
a | Rect to compare |
b | Rect to compare |
Return Value
true if members are equal
Example
Example Output
tests are equal
{0, 0, 2, 2} == {-0, -0, 2, 2} and are numerically equal
{0, 0, 2, 2} == {-0, -0, 2, 2} and are numerically equal
{0, 0, 2, 2} == {-0, -0, 2, 2} and are numerically equal
See Also
operator!=(const SkRect& a, const SkRect& b)
operator!=
friend bool operator!=(const SkRect& a, const SkRect& b)
Returns true if any in a: fLeft, fTop, fRight, and fBottom; does not
equal the corresponding members in b.
a and b are not equal if either contain NaN. a and b are equal if members contain zeroes width different signs.
Parameters
a | Rect to compare |
b | Rect to compare |
Return Value
true if members are not equal
Example
Example Output
test with NaN is not equal to itself
See Also
operator==(const SkRect& a, const SkRect& b)
toQuad
void toQuad(SkPoint quad[4]) const
Returns four points in quad that enclose Rect ordered as: top-left, top-right, bottom-right, bottom-left.
Parameters
quad | storage for corners of Rect |
Example
Example Output
rect: {1, 2, 3, 4}
corners: {1, 2} {3, 2} {3, 4} {1, 4}
See Also
setEmpty
void setEmpty()
Sets Rect 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.
Example
Example Output
rect: {3, 4, 1, 2} is empty
rect: {0, 0, 0, 0} is empty
See Also
set
void set(const SkIRect& src)
Sets Rect to src, promoting src members from integer to Scalar. Very large values in src may lose precision.
Parameters
src | integer Rect |
Example
Example Output
i_rect: {3, 4, 1, 2}
f_rect: {3, 4, 1, 2}
See Also
void set(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom)
Sets Rect 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.
Parameters
left | stored in fLeft |
top | stored in fTop |
right | stored in fRight |
bottom | stored in fBottom |
Example
Example Output
rect1: {3, 4, 1, 2}
rect2: {3, 4, 1, 2}
See Also
setLTRB
void setLTRB(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom)
Sets Rect 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.
Parameters
left | stored in fLeft |
top | stored in fTop |
right | stored in fRight |
bottom | stored in fBottom |
Example
Example Output
rect1: {3, 4, 1, 2}
rect2: {3, 4, 1, 2}
See Also
iset
void iset(int left, int top, int right, int bottom)
Sets Rect to (left, top, right, bottom). All parameters are promoted from integer to Scalar. 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.
Parameters
left | promoted to SkScalar and stored in fLeft |
top | promoted to SkScalar and stored in fTop |
right | promoted to SkScalar and stored in fRight |
bottom | promoted to SkScalar and stored in fBottom |
Example
Example Output
rect1: {3, 4, 1, 2}
rect2: {3, 4, 1, 2}
See Also
set setLTRB SkIRect::set SkIntToScalar
isetWH
void isetWH(int width, int height)
Sets Rect to (0, 0, width, height). width and height may be zero or negative. width and height are promoted from integer to SkScalar, large values may lose precision.
Parameters
width | promoted to SkScalar and stored in fRight |
height | promoted to SkScalar and stored in fBottom |
Example
Example Output
rect1: {0, 0, 1, 2}
rect2: {0, 0, 1, 2}
See Also
MakeWH MakeXYWH iset SkIRect:MakeWH
void set(const SkPoint pts[], int count)
Sets to bounds of Point array with count entries. If count is zero or smaller, or if Point array contains an infinity or NaN, sets Rect to (0, 0, 0, 0).
Result is either empty or sorted: fLeft is less than or equal to fRight, and fTop is less than or equal to fBottom.
Parameters
pts | Point array |
count | entries in array |
Example
Example Output
count: 0 rect: 0, 0, 0, 0
added: 3, 4 count: 1 rect: 3, 4, 3, 4
added: 1, 2 count: 2 rect: 1, 2, 3, 4
added: 5, 6 count: 3 rect: 1, 2, 5, 6
added: nan, 8 count: 4 rect: 0, 0, 0, 0
See Also
setBounds setBoundsCheck SkPath::addPoly
setBounds
void setBounds(const SkPoint pts[], int count)
Sets to bounds of Point array with count entries. If count is zero or smaller, or if Point array contains an infinity or NaN, sets to (0, 0, 0, 0).
Result is either empty or sorted: fLeft is less than or equal to fRight, and fTop is less than or equal to fBottom.
Parameters
pts | Point array |
count | entries in array |
Example
Example Output
count: 0 rect: 0, 0, 0, 0
added: 3, 4 count: 1 rect: 3, 4, 3, 4
added: 1, 2 count: 2 rect: 1, 2, 3, 4
added: 5, 6 count: 3 rect: 1, 2, 5, 6
added: nan, 8 count: 4 rect: 0, 0, 0, 0
See Also
set setBoundsCheck SkPath::addPoly
setBoundsCheck
bool setBoundsCheck(const SkPoint pts[], int count)
Sets to bounds of Point array with count entries. Returns false if count is zero or smaller, or if Point array contains an infinity or NaN; in these cases sets Rect to (0, 0, 0, 0).
Result is either empty or sorted: fLeft is less than or equal to fRight, and fTop is less than or equal to fBottom.
Parameters
pts | Point array |
count | entries in array |
Return Value
true if all Point values are finite
Example
Example Output
count: 0 rect: 0, 0, 0, 0 success: true
added: 3, 4 count: 1 rect: 3, 4, 3, 4 success: true
added: 1, 2 count: 2 rect: 1, 2, 3, 4 success: true
added: 5, 6 count: 3 rect: 1, 2, 5, 6 success: true
added: nan, 8 count: 4 rect: 0, 0, 0, 0 success: false
See Also
void set(const SkPoint& p0, const SkPoint& p1)
Sets bounds to the smallest Rect enclosing Points p0 and p1. The result is sorted and may be empty. Does not check to see if values are finite.
Parameters
p0 | corner to include |
p1 | corner to include |
Example
See Also
setXYWH
void setXYWH(SkScalar x, SkScalar y, SkScalar width, SkScalar height)
Sets Rect to(x, y, x + w, y + h). Does not validate input; w or h may be negative.
Parameters
x | stored in fLeft |
y | stored in fTop |
width | added to x and stored in fRight |
height | added to y and stored in fBottom |
Example
Example Output
rect: 5, 35, -10, 60 isEmpty: true
rect: -10, 35, 5, 60 isEmpty: false
See Also
MakeXYWH setLTRB set SkIRect::setXYWH
setWH
void setWH(SkScalar width, SkScalar height)
Sets Rect to (0, 0, w, h). Does not validate input; w or h may be negative.
Parameters
width | stored in fRight |
height | stored in fBottom |
Example
Example Output
rect: 0, 0, -15, 25 isEmpty: true
rect: -15, 0, 0, 25 isEmpty: false
See Also
setLargest
void setLargest()
Sets rectangle left and top to most negative finite value, and sets right and bottom to most positive finite value.
Example
Example Output
MakeLargest isLargest: true
MakeLargest isFinite: true
outset a little isLargest: true
outset a little isFinite: true
outset a little more isLargest: false
outset a little more isFinite: false
See Also
MakeLargest isLargest setLargestInverted SK ScalarMin SK ScalarMax
setLargestInverted
void setLargestInverted()
Sets rectangle left and top to most positive finite value, and sets right and bottom to most negative finite value.
Use to initial Rect before one or more calls to growToInclude.
Example
Example Output
original rect: 3.40282e+38, 3.40282e+38, -3.40282e+38, -3.40282e+38 isEmpty: true
grown rect: 42, 24, 42, 24 isEmpty: true
See Also
growToInclude setEmpty setLargest
makeOffset
SkRect makeOffset(SkScalar dx, SkScalar dy) const
Returns Rect offset by (dx, dy).
If dx is negative, Rect returned is moved to the left. If dx is positive, Rect returned is moved to the right. If dy is negative, Rect returned is moved upward. If dy is positive, Rect returned is moved downward.
Parameters
dx | added to fLeft and fRight |
dy | added to fTop and fBottom |
Return Value
Rect offset in x or y, with original width and height
Example
Example Output
rect: 10, 50, 20, 60 isEmpty: false
rect: 25, 82, 35, 92 isEmpty: false
See Also
offset makeInset makeOutset SkIRect::makeOffset
makeInset
SkRect makeInset(SkScalar dx, SkScalar dy) const
Returns Rect, inset by (dx, dy).
If dx is negative, Rect returned is wider. If dx is positive, Rect returned is narrower. If dy is negative, Rect returned is taller. If dy is positive, Rect returned is shorter.
Parameters
dx | added to fLeft and subtracted from fRight |
dy | added to fTop and subtracted from fBottom |
Return Value
Rect inset symetrically left and right, top and bottom
Example
Example Output
rect: 10, 50, 20, 60 isEmpty: false
rect: 25, 82, 5, 28 isEmpty: true
See Also
inset makeOffset makeOutset SkIRect::makeInset
makeOutset
SkRect makeOutset(SkScalar dx, SkScalar dy) const
Returns Rect, outset by (dx, dy).
If dx is negative, Rect returned is narrower. If dx is positive, Rect returned is wider. If dy is negative, Rect returned is shorter. If dy is positive, Rect returned is taller.
Parameters
dx | subtracted to fLeft and added from fRight |
dy | subtracted to fTop and added from fBottom |
Return Value
Rect outset symetrically left and right, top and bottom
Example
Example Output
rect: 10, 50, 20, 60 isEmpty: false
rect: -5, 18, 35, 92 isEmpty: false
See Also
outset makeOffset makeInset SkIRect::makeOutset
offset
void offset(SkScalar dx, SkScalar dy)
Offsets Rect by adding dx to fLeft, fRight; and by adding dy to fTop, fBottom.
If dx is negative, moves Rect to the left. If dx is positive, moves Rect to the right. If dy is negative, moves Rect upward. If dy is positive, moves Rect downward.
Parameters
dx | offset added to fLeft and fRight |
dy | offset added to fTop and fBottom |
Example
Example Output
rect: 15, 27, 55, 86
See Also
offsetTo makeOffset SkIRect::offset
void offset(const SkPoint& delta)
Offsets Rect by adding delta.fX to fLeft, fRight; and by adding delta.fY to fTop, fBottom.
If delta.fX is negative, moves Rect to the left. If delta.fX is positive, moves Rect to the right. If delta.fY is negative, moves Rect upward. If delta.fY is positive, moves Rect downward.
Parameters
delta | added to Rect |
Example
Example Output
rect: 15, 27, 55, 86
See Also
offsetTo makeOffset SkIRect::offset
offsetTo
void offsetTo(SkScalar newX, SkScalar newY)
Offsets Rect so that fLeft equals newX, and fTop equals newY. width and height are unchanged.
Parameters
newX | stored in fLeft, preserving width |
newY | stored in fTop, preserving height |
Example
Example Output
rect: 15, 27, 55, 86
See Also
offset makeOffset setXYWH SkIRect::offsetTo
inset
void inset(SkScalar dx, SkScalar dy)
If dx is positive, makes Rect narrower. If dx is negative, makes Rect wider. If dy is positive, makes Rect shorter. If dy is negative, makes Rect taller.
Parameters
dx | added to fLeft and subtracted from fRight |
dy | added to fTop and subtracted from fBottom |
Example
Example Output
rect: 15, 27, 45, 60
See Also
outset makeInset SkIRect::inset
outset
void outset(SkScalar dx, SkScalar 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.
Parameters
dx | subtracted to fLeft and added from fRight |
dy | subtracted to fTop and added from fBottom |
Example
Example Output
rect: 5, 1, 55, 86
See Also
inset makeOutset SkIRect::outset
Intersection
Rects 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 Rect a and Rect b 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 Rect is not empty and describes an area: fLeft is less than fRight, and fTop is less than fBottom.
intersect
bool intersect(const SkRect& r)
Returns true if Rect intersects r, and sets Rect to intersection. Returns false if Rect does not intersect r, and leaves Rect unchanged.
Returns false if either r or Rect is empty, leaving Rect unchanged.
Parameters
r | limit of result |
Return Value
true if r and Rect have area in common
Example
Example Output
intersection: 30, 60, 50, 80
See Also
intersects Intersects join SkIRect::intersect
bool intersect(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom)
Constructs Rect to intersect from (left, top, right, bottom). Does not sort construction.
Returns true if Rect intersects construction, and sets Rect to intersection. Returns false if Rect does not intersect construction, and leaves Rect unchanged.
Returns false if either construction or Rect is empty, leaving Rect unchanged.
Parameters
left | x minimum of constructed Rect |
top | y minimum of constructed Rect |
right | x maximum of constructed Rect |
bottom | y maximum of constructed Rect |
Return Value
true if construction and Rect have area in common
Example
Example Output
intersection: 30, 60, 50, 80
See Also
intersects Intersects join SkIRect::intersect
bool SK_WARN_UNUSED_RESULT intersect(const SkRect& a, const SkRect& b)
Returns true if a intersects b, and sets Rect to intersection. Returns false if a does not intersect b, and leaves Rect unchanged.
Returns false if either a or b is empty, leaving Rect unchanged.
Parameters
a | Rect to intersect |
b | Rect to intersect |
Return Value
true if a and b have area in common
Example
Example Output
intersection: 30, 60, 50, 80
See Also
intersects Intersects join SkIRect::intersect
intersects
bool intersects(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom) const
Constructs Rect to intersect from (left, top, right, bottom). Does not sort construction.
Returns true if Rect intersects construction. Returns false if either construction or Rect is empty, or do not intersect.
Parameters
left | x minimum of constructed Rect |
top | y minimum of constructed Rect |
right | x maximum of constructed Rect |
bottom | y maximum of constructed Rect |
Return Value
true if construction and Rect have area in common
Example
Example Output
intersection
See Also
intersect Intersects SkIRect::Intersects
bool intersects(const SkRect& r) const
Returns true if Rect intersects r. Returns false if either r or Rect is empty, or do not intersect.
Parameters
r | Rect to intersect |
Return Value
true if r and Rect have area in common
Example
Example Output
intersection
See Also
intersect Intersects SkIRect::Intersects
Intersects
static bool Intersects(const SkRect& a, const SkRect& b)
Returns true if a intersects b. Returns false if either a or b is empty, or do not intersect.
Parameters
a | Rect to intersect |
b | Rect to intersect |
Return Value
true if a and b have area in common
Example
Example Output
intersection
See Also
intersect intersects SkIRect::Intersects
join
void join(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom)
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.
Parameters
left | x minimum of constructed Rect |
top | y minimum of constructed Rect |
right | x maximum of constructed Rect |
bottom | y maximum of constructed Rect |
Example
Example Output
join: 10, 20, 55, 65
See Also
joinNonEmptyArg joinPossiblyEmptyRect SkIRect::join
void join(const SkRect& r)
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.
Parameters
r | expansion Rect |
Example
Example Output
join: 10, 20, 55, 65
See Also
joinNonEmptyArg joinPossiblyEmptyRect SkIRect::join
joinNonEmptyArg
void joinNonEmptyArg(const SkRect& r)
Sets Rect to the union of itself and r.
Asserts if r is empty and SK DEBUG is defined. If Rect is empty, sets rect to r.
May produce incorrect results if r is empty.
Parameters
r | expansion Rect |
Example
Example Output
rect: 50, 60, 55, 65
sorted: 10, 0, 55, 100
See Also
join joinPossiblyEmptyRect SkIRect::join
joinPossiblyEmptyRect
void joinPossiblyEmptyRect(const SkRect& r)
Sets Rect to the union of itself and the construction.
May produce incorrect results if Rect or r is empty.
Parameters
r | expansion Rect |
Example
Example Output
rect: 10, 60, 55, 65
sorted: 10, 0, 55, 100
See Also
joinNonEmptyArg join SkIRect::join
growToInclude
void growToInclude(SkPoint pt)
Grows Rect to include (pt.fX, pt.fY), modifying it so that: fLeft <= pt.fX <= fRight && fTop <= pt.fY <= fBottom.
If Rect is initialized with setLargestInverted, then Rect will contain bounds of Points after one or more calls. In this case, Rect is empty after first call.
Parameters
pt | Point to include |
Example
Example Output
rect: 42, 24, 42, 24 isEmpty: true
See Also
void growToInclude(const SkPoint pts[], int count)
For each of count Point in pts, grows Rect to include (pt.fX, pt.fY), modifying it so that: fLeft <= pt.fX <= fRight && fTop <= pt.fY <= fBottom.
If Rect is initialized with setLargestInverted, then Rect will contain bounds of Points after one or more calls. In this case, Rect is empty after first call.
Parameters
pts | Point array |
count | number of points in array |
Example
Example Output
rect: 30, 50, 40, 60
See Also
void growToInclude(const SkPoint pts[], size_t stride, int count)
For each of count Point in pts, grows Rect to include (pt.fX, pt.fY), modifying it so that: fLeft <= pt.fX <= fRight && fTop <= pt.fY <= fBottom. Point may be followed with other data in each array element. stride is number of bytes in element; the interval to skip to advance from one Point to the next.
If Rect is initialized with setLargestInverted, then Rect will contain bounds of Points after one or more calls. In this case, Rect is empty after first call.
Parameters
pts | array of elements beginning with Point |
stride | size of pts elements in 32-bit words; zero or greater |
count | number of elements in array |
Example
Example Output
#Volatile
rect: 30, 50, 40, 60
See Also
contains
bool contains(const SkRect& r) const {
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.
Parameters
r | Rect contained |
Return Value
true if all sides of Rect are outside r
Example
Example Output
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)
See Also
bool contains(const SkIRect& r) const
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.
Parameters
r | IRect contained |
Return Value
true if all sides of Rect are outside r
Example
Example Output
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)
See Also
Round
round
void round(SkIRect* dst) const
Sets IRect by adding 0.5 and discarding the fractional portion of Rect members, using(.
Parameters
dst | storage for IRect |
Example
Example Output
round: 31, 51, 41, 61
See Also
roundIn roundOut SkScalarRoundToInt
roundOut
void roundOut(SkIRect* dst) const
Sets IRect by discarding the fractional portion of fLeft and fTop; and rounding up fRight and FBottom, using(.
Parameters
dst | storage for IRect |
Example
Example Output
round: 30, 50, 41, 61
See Also
roundIn round SkScalarRoundToInt
void roundOut(SkRect* dst) const
Sets Rect by discarding the fractional portion of fLeft and fTop; and rounding up fRight and FBottom, using(.
Parameters
dst | storage for Rect |
Example
Example Output
round: 30, 50, 41, 61
See Also
roundIn round SkScalarRoundToInt
roundIn
void roundIn(SkIRect* dst) const
Sets Rect by rounding up fLeft and fTop; and discarding the fractional portion of fRight and FBottom, using(.
Parameters
dst | storage for IRect |
Example
Example Output
round: 31, 51, 40, 60
See Also
roundOut round SkScalarRoundToInt
SkIRect round() const
Returns IRect by adding 0.5 and discarding the fractional portion of Rect members, using(.
Return Value
rounded IRect
Example
Example Output
round: 31, 51, 41, 61
See Also
roundOut roundIn SkScalarRoundToInt
SkIRect roundOut() const
Sets IRect by discarding the fractional portion of fLeft and fTop; and rounding up fRight and FBottom, using(.
Return Value
rounded IRect
Example
Example Output
round: 30, 50, 41, 61
See Also
round roundIn SkScalarRoundToInt
sort
void sort()
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.
Example
Example Output
rect: 30.5, 50.5, 20.5, 10.5
sorted: 20.5, 10.5, 30.5, 50.5
See Also
makeSorted
SkRect makeSorted() const
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.
Return Value
sorted Rect
Example
Example Output
rect: 30.5, 50.5, 20.5, 10.5
sorted: 20.5, 10.5, 30.5, 50.5
See Also
asScalars
const SkScalar* asScalars() const
Returns pointer to first Scalar in Rect, to treat it as an array with four entries.
Return Value
pointer to fLeft
Example
Example Output
rect.asScalars() == &rect.fLeft
See Also
dump
void dump(bool asHex) const
Writes text representation of Rect to standard output. Set asHex to true to generate exact binary representations of floating point numbers.
Parameters
asHex | true if SkScalar values are written as hexadecimal |
Example
Example Output
SkRect::MakeLTRB(20, 30, 40, 50);
SkRect::MakeLTRB(SkBits2Float(0x41a00000), /* 20.000000 */
SkBits2Float(0x41f00000), /* 30.000000 */
SkBits2Float(0x42200000), /* 40.000000 */
SkBits2Float(0x42480000) /* 50.000000 */);
See Also
void dump() const
Writes text representation of Rect to standard output. The representation may be directly compiled as C++ code. Floating point values are written with limited precision; it may not be possible to reconstruct original Rect from output.
Example
Example Output
SkRect::MakeLTRB(0.857143f, 0.666667f, 2.6f, 7);
rect is not equal to copy
See Also
dumpHex
void dumpHex() const
Writes text representation of Rect to standard output. The representation may be directly compiled as C++ code. Floating point values are written in hexadecimal to preserve their exact bit pattern. The output reconstructs the original Rect.
Use instead of dump when submittingbug reports against Skia.
Example
Example Output
SkRect::MakeLTRB(SkBits2Float(0x3f5b6db7), /* 0.857143 */
SkBits2Float(0x3f2aaaab), /* 0.666667 */
SkBits2Float(0x40266666), /* 2.600000 */
SkBits2Float(0x40e00000) /* 7.000000 */);
rect is equal to copy