Class Rect

GoJS® Diagramming Components
version 3.0.0
by Northwoods Software®

A Rect describes a rectangular two-dimensional area as a top-left point (x and y values) and a size (width and height values).

Use the static functions Rect.parse and Rect.stringify to convert to and from a standard string representation that is independent of the current locale.

When an instance of this class is the value of a property of a GraphObject class or Diagram or CommandHandler or a Tool class, you should treat the object as if it were frozen or read-only -- you cannot modify its properties. This allows the property to return a value without allocating a new instance. If you need to do your own calculations with the value, call copy to make a new instance with the same values that you can modify.

Many methods modify the object's properties and then return a reference to "this" object. The only instance method to allocate a new object is the copy method. The static Rect.parse method also allocates a new object. The center, position, and size properties all allocate and return a new object.

The "Debug" implementation of this class is significantly slower than the "Release" implementation, mostly due to additional error checking.

You cannot inherit from this class.

Constructors

constructor

new Rect(x?: number | Point, y?: number | Point | Size, w?: number, h?: number): Rect
There are four constructors: (), (Point, Point), (Point, Size), and four numbers for (x, y, width, height). The default constructor (no argument) results in a Rect(0,0,0,0).
Parameters
- Optional x: number | Point
  Top-left Point, or x value.
- Optional y: number | Point | Size
  Bottom-right Point or Size or y value.
- Optional w: number
  Width to be used if x,y are specified; must be non-negative.
- Optional h: number
  Height to be used if x,y are specified; must be non-negative.
Returns Rect

Accessors

bottom
: number

Gets or sets the y-axis value of the bottom of the Rect. This is equal to the sum of the y value and the height.

center
: Point

Gets or sets the Point at the center of this Rect. Setting this property just shifts the X and Y values.

centerX
: number

Gets or sets the horizontal center X coordinate of the Rect.

centerY
: number

Gets or sets the vertical center Y coordinate of the Rect.

height
: number

Gets or sets the height of the Rect. The value must not be negative.

left
: number

Gets or sets the leftmost value of the Rect. This is the same as the X value.

position
: Point

Gets or sets the x- and y-axis position of the Rect as a Point.

right
: number

Gets or sets the x-axis value of the right of the Rect. This is equal to the sum of the x value and the width.

size
: Size

Gets or sets the width and height of the Rect as a Size.

top
: number

Gets or sets the topmost value of the Rect. This is the same as the Y value.

width
: number

Gets or sets the width of the Rect. The value must not be negative.

x
: number

Gets or sets the top-left x coordinate of the Rect.

y
: number

Gets or sets the top-left y coordinate of the Rect.

Methods

addMargin

addMargin(m: Margin): Rect
Modify this Rect by adding the given Margin to each side of the Rect.
Parameters
- m: Margin
  The Margin to add to the Rect.
Returns Rect
this bigger Rect.
see

contains

contains(x: number, y: number, w?: number, h?: number): boolean
Indicates whether this Rect contains the given Point/Rect.
Parameters
- x: number
  The X coordinate of the Point or Rect to include in the new bounds.
- y: number
  The Y coordinate of the Point or Rect to include in the new bounds.
- Optional w: number
  The Width of the Rect to include in the new bounds, defaults to zero.
- Optional h: number
  The Height of the Rect to include in the new bounds, defaults to zero.
Returns boolean
True if the Point/Rect is contained within this Rect, false otherwise.
see
- containsRect
- containsPoint

containsPoint

containsPoint(p: Point): boolean
Indicates whether this Rect contains the given Point.
Parameters
- p: Point
  The Point to check.
Returns boolean
True if the Point is contained within this Rect, false otherwise.
see
- containsRect
- contains

containsRect

containsRect(r: Rect): boolean
Indicates whether this Rect contains the given Rect.
Parameters
- r: Rect
  The Rect to check.
Returns boolean
True if the Rect is contained within this Rect, false otherwise.
see
- containsPoint
- contains

`Virtual`copy

copy(): Rect
Create a copy of this Rect, with the same values.

Returns Rect

equalTo

equalTo(x: number, y: number, w: number, h: number): boolean
Indicates whether the given Rect is equal to the current Rect.
Parameters
- x: number
- y: number
- w: number
  the width.
- h: number
  the height.
Returns boolean
True if the Rects are equivalent in x, y, width, and height.

see
equals

equals

equals(r: Rect): boolean
Indicates whether the given Rect is equal to the current Rect.
Parameters
- r: Rect
  The rectangle to compare to the current rectangle.
Returns boolean
True if the Rects are equivalent in x, y, width, and height.

see
equalTo

grow

grow(t: number, r: number, b: number, l: number): Rect
Modifies this Rect by adding some distance to each side of the Rect.
Parameters
- t: number
  the amount to move the top side upwards; may be negative.
- r: number
  the amount to move the right side rightwards; may be negative.
- b: number
  the amount to move the bottom side downwards; may be negative.
- l: number
  the amount to move the left side leftwards; may be negative.
Returns Rect
this modified Rect.
see

inflate

inflate(w: number, h: number): Rect
Modify this Rect so that its width and height are changed on all four sides, equally on the left and right sides, and equally on the top and bottom sides. When the arguments are negative, this operation deflates this Rect, but not beyond zero.
Parameters
- w: number
  The additional width on each side, left and right; may be negative.
- h: number
  The additional height on each side, top and bottom; may be negative.
Returns Rect
this.
since
2.3
see

intersect

intersect(x: number, y: number, w: number, h: number): Rect
Modify this Rect so that it is the intersection of this Rect and the rectangle defined by x, y, w, h.
Parameters
- x: number
- y: number
- w: number
- h: number
Returns Rect
this.
see
- intersectRect
- intersects

intersectRect

intersectRect(r: Rect): Rect
Modify this Rect so that it is the intersection of this Rect and the given Rect.
Parameters
- r: Rect
  Rect to intersect with.
Returns Rect
this.
see
- intersect
- intersects

intersects

intersects(x: number, y: number, w: number, h: number): boolean
Determine if this Rect partly or wholly overlaps the rectangle defined by x, y, w, h.
Parameters
- x: number
- y: number
- w: number
- h: number
Returns boolean
true if there is any overlap.
see
- intersectsRect
- intersect

intersectsRect

intersectsRect(r: Rect): boolean
Determine if a given Rect is partly or wholly inside of this Rect.
Parameters
- r: Rect
  Rect to test intersection with.
Returns boolean
true if there is an intersection.
see
- intersects
- intersectRect

isEmpty

isEmpty(): boolean
True if this Rect has a Width and Height of zero.

Returns boolean

isReal

isReal(): boolean
True if this Rect has X, Y, Width, and Height values that are real numbers and not infinity.

Returns boolean

offset

offset(dx: number, dy: number): Rect
Modify this Rect by shifting its values with the given DX and DY offsets.
Parameters
- dx: number
- dy: number
Returns Rect
this.

set

set(r: Rect): Rect
Modify this Rect so that its X, Y, Width, and Height values are the same as the given Rect.
Parameters
- r: Rect
  the given Rect.
Returns Rect
this.

setPoint

setPoint(p: Point): Rect
Modify this Rect so that its X and Y values are the same as the given Point.
Parameters
- p: Point
  the given Point.
Returns Rect
this.

setSize

setSize(s: Size): Rect
Modify this Rect so that its Width and Height values are the same as the given Size.
Parameters
- s: Size
  the given Size.
Returns Rect
this.

setSpot

setSpot(x: number, y: number, spot: Spot): Rect
Modify this Rect so that a given Spot is at a given (x,y) point using this Rect's size. Return this rectangle for which the spot is at that point, without modifying the size.

The result is meaningless if Spot.isNoSpot is true.
Parameters
- x: number
  the point where the spot should be.
- y: number
  the point where the spot should be.
- spot: Spot
  a Spot; Spot.isSpot must be true.
Returns Rect
this.

setTo

setTo(x: number, y: number, w: number, h: number): Rect
Modify this Rect with new X, Y, Width, and Height values.
Parameters
- x: number
- y: number
- w: number
  the width.
- h: number
  the height.
Returns Rect
this.

subtractMargin

subtractMargin(m: Margin): Rect
Modify this Rect by subtracting the given Margin from each side of the Rect.
Parameters
- m: Margin
  The Margin to subtract from the Rect.
Returns Rect
this smaller Rect.
see
- addMargin
- grow
- inflate

union

union(x: number, y: number, w?: number, h?: number): Rect
Modify this Rect to be exactly big enough to contain both the original Rect and the given rectangular area.
Parameters
- x: number
  The X coordinate of the Point or Rect to include in the new bounds.
- y: number
  The Y coordinate of the Point or Rect to include in the new bounds.
- Optional w: number
  The Width of the Rect to include in the new bounds, defaults to zero.
- Optional h: number
  The Height of the Rect to include in the new bounds, defaults to zero.
Returns Rect
this.
see
- unionRect
- unionPoint

unionPoint

unionPoint(p: Point): Rect
Modify this Rect to be exactly big enough to contain both the original Rect and the given Point.
Parameters
- p: Point
  The Point to include in the new bounds.
Returns Rect
this.
see
- unionRect
- union

unionRect

unionRect(r: Rect): Rect
Modify this Rect to be exactly big enough to contain this Rect and the given Rect.
Parameters
- r: Rect
  The Rect to include in the new bounds.
Returns Rect
this.
see
- unionPoint
- union

`Static` contains

contains(rx: number, ry: number, rw: number, rh: number, x: number, y: number, w?: number, h?: number): boolean
This static function indicates whether a Rect contains the given Point/Rect.
Parameters
- rx: number
  The X coordinate of a Rect.
- ry: number
  The Y coordinate of a Rect.
- rw: number
  The Width of a Rect.
- rh: number
  The Height of a Rect.
- x: number
  The X coordinate of the Point or Rect that might be in the bounds (RX, RY, RW, RH).
- y: number
  The Y coordinate of the Point or Rect that might be in the bounds (RX, RY, RW, RH).
- Optional w: number
  The Width of the Rect to include in the new bounds, defaults to zero.
- Optional h: number
  The Height of the Rect to include in the new bounds, defaults to zero.
Returns boolean
True if the Point/Rect is contained within this Rect, false otherwise.

`Static` intersects

intersects(rx: number, ry: number, rw: number, rh: number, x: number, y: number, w: number, h: number): boolean
This static function indicates whether a Rect partly or wholly overlaps the given Rect.
Parameters
- rx: number
  The X coordinate of a Rect.
- ry: number
  The Y coordinate of a Rect.
- rw: number
  The Width of a Rect.
- rh: number
  The Height of a Rect.
- x: number
  The X coordinate of the Point or Rect that might overlap the bounds (RX, RY, RW, RH).
- y: number
  The Y coordinate of the Point or Rect that might overlap the bounds (RX, RY, RW, RH).
- w: number
- h: number
Returns boolean
true if there is any overlap.

`Static` intersectsLineSegment

intersectsLineSegment(x: number, y: number, w: number, h: number, p1x: number, p1y: number, p2x: number, p2y: number): boolean
This static function is true if a rectangular area is intersected by a finite straight line segment.
Parameters
- x: number
  The X coordinate of the rectangle to check for intersection with the line segment.
- y: number
  The Y coordinate of the rectangle to check for intersection with the line segment.
- w: number
  The Width of the rectangle to check for intersection with the line segment.
- h: number
  The Height of the rectangle to check for intersection with the line segment.
- p1x: number
  The X coordinate of one end of the line segment.
- p1y: number
  The Y coordinate of one end of the line segment.
- p2x: number
  The X coordinate of other end of the line segment.
- p2y: number
  The Y coordinate of other end of the line segment.
Returns boolean
True if the given finite line segment intersects with the given rectangular area, false otherwise.

since
2.2

`Static` parse

parse(str: string): Rect
This static function can be used to read in a Rect from a string that was produced by Rect.stringify.

go.Rect.parse("1 2 3 4") produces the Rect new go.Rect(1, 2, 3, 4).
Parameters
- str: string
Returns Rect

`Static` stringify

stringify(val: Rect): string
This static function can be used to write out a Rect as a string that can be read by Rect.parse.

go.Rect.stringify(new go.Rect(1, 2, 3, 4)) produces the string "1 2 3 4".
Parameters
- val: Rect
Returns string

`Static` stringifyFixed

stringifyFixed(digits: number): ((val: Rect) => string)
This static function returns a function that can be used as a back converter for a Binding to write out a Rect's values as numbers with a fixed number of digits after the decimal point.

This is useful for limiting the size of JSON output and making it more legible. It might also be useful for regression testing.
Parameters
- digits: number
  must be a non-negative integer
Returns ((val: Rect) => string)
a function that converts a Rect to a string without so many decimals
- - (val: Rect): string
  - This static function returns a function that can be used as a back converter for a Binding to write out a Rect's values as numbers with a fixed number of digits after the decimal point.
    
    This is useful for limiting the size of JSON output and making it more legible. It might also be useful for regression testing.
    Parameters
    - val: Rect
    Returns string
    a function that converts a Rect to a string without so many decimals
    
    since
    3.0
since
3.0

Class Rect

Index

Constructors

Accessors

Methods

Constructors

constructor

Parameters

Optional x: number | Point

Optional y: number | Point | Size

Optional w: number

Optional h: number

Returns Rect

Accessors

bottom: number

center: Point

centerX: number

centerY: number

height: number

left: number

position: Point

right: number

size: Size

top: number

width: number

x: number

y: number

Methods

addMargin

Parameters

m: Margin

Returns Rect

contains

Parameters

x: number

y: number

Optional w: number

Optional h: number

Returns boolean

containsPoint

Parameters

p: Point

Returns boolean

containsRect

Parameters

r: Rect

Returns boolean

Virtualcopy

Returns Rect

equalTo

Parameters

x: number

y: number

w: number

h: number

Returns boolean

equals

Parameters

r: Rect

Returns boolean

grow

Parameters

t: number

r: number

b: number

l: number

Returns Rect

inflate

Parameters

w: number

h: number

Returns Rect

intersect

Parameters

x: number

y: number

w: number

h: number

Returns Rect

intersectRect

`Optional` x: number | Point

`Optional` y: number | Point | Size

`Optional` w: number

`Optional` h: number

bottom
: number

center
: Point

centerX
: number

centerY
: number

height
: number

left
: number

position
: Point

right
: number

size
: Size

top
: number

width
: number

x
: number

y
: number

`Optional` w: number

`Optional` h: number

`Virtual`copy

`Optional` w: number

`Optional` h: number

`Static` contains