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Rectangle

If a function receives a rectangle as an argument it could be several things:

  1. You can specify the parameters x, y, width, height directly as arguments of the function. E.g. sprite:crop(0, 16, 64, 32)
  2. You can specify an object with x, y, width, and height properties. E.g. sprite:crop{ x=0, y=16, width=64, height=32 }
  3. You can specify an array with 4 elements: E.g. sprite:crop{ 0, 16, 64, 32 }
  4. You can specify a Rectangle instance: E.g. sprite:crop(Rectangle(0, 16, 64, 32))

Rectangle()

Rectangle()
Rectangle(otherRectangle)
Rectangle(x, y, width, height)
Rectangle{x=number, y=number, width=number, height=number}
Rectangle{number, number, number, number}

Rectangle.x

local x = rectangle.x
rectangle.x = newX

Gets or sets the x-coordinate of the rectangle. 0 means at the left side of the screen/sprite.

Rectangle.y

local y = rectangle.y
rectangle.y = newY

Gets or sets the y-coordinate of the rectangle. 0 means at the top side of the screen/sprite.

Rectangle.width

local width = rectangle.width
rectangle.width = newWidth

Gets or sets the width of the rectangle. If it's 0, the rectangle is empty (so the coordinate doesn't matter).

Rectangle.height

local height = rectangle.height
rectangle.height = newHeight

Gets or sets the height of the rectangle. If it's 0, the rectangle is empty (so the coordinate doesn't matter).

Rectangle.origin

local point = rectangle.origin
rectangle.origin = newPoint

Gets or sets the origin of the rectangle with a Point object, just like changing Rectangle.x and Rectangle.y at the same time.

Rectangle.size

local size = rectangle.size
rectangle.size = newSize

Gets or sets the size of the rectangle with a Size object, just like changing Rectangle.width and Rectangle.height at the same time.

Rectangle.isEmpty

local booleanResult = rectangle.isEmpty

Returns true if the rectangle is empty i.e. width and/or height are 0.

Rectangle:contains()

local booleanResult = rectangle:contains(otherRectangle)

Returns true if otherRectangle is inside rectangle.

Example:

local bounds = Rectangle{ x=0, y=0, width=32, height=32 }
local rectInside = Rectangle{ x=4, y=4, width=8, height=8 }
if bounds:contains(rectInside) then ... end

Rectangle:intersects()

local booleanResult = rectangle:intersects(otherRectangle)

Returns true if rectangle intersects in some way otherRectangle.

Rectangle:intersect()

local newRectangle = rectangle:intersect(otherRectangle)

Returns the new rectangle newRectangle which is the intersection of rectangle and otherRectangle. If both rectangles don't intersect each other, the result will be an empty rectangle

Rectangle:union()

local newRectangle = rectangle:union(otherRectangle)

Returns the new rectangle newRectangle which will be a rectangle big enough to contains both given rectangles rectangle and otherRectangle.