CRect:Class Operators

CRect Class Operators

The CRect class supports several math operations between rectangles and other objects or numbers. Operators make it possible for a script to contain expressions like the following:

R2 = 0.5 * R	-- creates a new rectangle R2 half as large as R.
R3 = (R1 - R2) * 2.5	-- subtracts R2 from R1 and multiples the result by 2.5.

Several operators have class method counterparts. For example, the alternative to using the + operator would be CRect:Offset. A primary difference between the operators and methods is that many of the operators create the result as a new CRect object, whereas methods operate on the object that calls them. Operators are provided for the arithmetic operations +-*/% and for comparisons.

Addition

R1 + R2	Adds two rectangles. For example, R3 = R1 + R2 is equivalent to R3 = NewRect( R1 ) R3:Offset( R2 )
R1 + t	Adds 4 Lua array elements to a rectangle. For example, R2 = R + t is equivalent to R2 = NewRect() R2.xmin = R1.xmin + t[0] R2.xmax = R1.xmax + t[1] R2.ymin = R1.ymin + t[2] R2.ymax = R1.ymax + t[3]
R1 + P	Adds a CPoint to a rectangle. This offsets the rectangle by P.x and P.y. For example, R2 = R + P is equivalent to R2 = NewRect() R2.xmin = R.xmin + P.x R2.xmax = R.xmax + P.x R2.ymin = R.ymin + P.y R2.ymax = R.ymax + P.y
R1 + num	Adds a number to a rectangle. For example, R2 = R + 0.5 is equivalent to R2 = NewRect() R2.xmin = R.xmin + 0.5 R2.xmax = R.xmax + 0.5 R2.ymin = R.ymin + 0.5 R2.ymax = R.ymax + 0.5

Subtraction

R1 - R2	Subtracts two rectangles. For example, R3 = R1 - R2 is equivalent to R3 = NewRect() R3.xmin = R2.xmin - R1.xmin R3.xmax = R2.xmax - R1.xmax R3.ymin = R2.ymin - R1.ymin R3.ymax = R2.ymax - R1.ymax
R1 - t	Subtracts 4 Lua array elements from a rectangle. For example, R2 = R - t is equivalent to R2 = NewRect() R2.xmin = R1.xmin - t[0] R2.xmax = R1.xmax - t[1] R2.ymin = R1.ymin - t[2] R2.ymax = R1.ymax - t[3]
R1 - P	Subtracts a CPoint from a rectangle. For example, R2 = R - P is equivalent to R2 = NewRect() R2.xmin = R.xmin - P.x R2.xmax = R.xmax - P.x R2.ymin = R.ymin - P.y R2.ymax = R.ymax - P.y
R1 - num	Subtracts a number from a rectangle. For example, R2 = R - 0.5 is equivalent to R2 = NewRect() R2.xmin = R.xmin - 0.5 R2.xmax = R.xmax - 0.5 R2.ymin = R.ymin - 0.5 R2.ymax = R.ymax - 0.5

Multiplication

R1 * R2	Multiplies two rectangles. For example, R3 = R1 * R2 is equivalent to R3 = NewRect() R3.xmin = R2.xmin * R1.xmin R3.xmax = R2.xmax * R1.xmax R3.ymin = R2.ymin * R1.ymin R3.ymax = R2.ymax * R1.ymax
R1 * t	Multiplies a rectangle by 4 Lua array elements. For example, R2 = R * t is equivalent to R2 = NewRect() R2.xmin = R1.xmin * t[0] R2.xmax = R1.xmax * t[1] R2.ymin = R1.ymin * t[2] R2.ymax = R1.ymax * t[3]
R1 * P	Multiplies a rectangle by a CPoint. For example, R2 = R * P is equivalent to R2 = NewRect() R2.xmin = R.xmin * P.x R2.xmax = R.xmax * P.x R2.ymin = R.ymin * P.y R2.ymax = R.ymax * P.y
R1 * num	Multiples a rectangle by a number. For example, R2 = R * 0.5 is equivalent to R2 = NewRect() R2.xmin = R.xmin * 0.5 R2.xmax = R.xmax * 0.5 R2.ymin = R.ymin * 0.5 R2.ymax = R.ymax * 0.5

Division

R1 / R2	Divides a rectangle by another rectangle. For example, R3 = R1 / R2 is equivalent to R3 = NewRect() R3.xmin = R2.xmin / R1.xmin R3.xmax = R2.xmax / R1.xmax R3.ymin = R2.ymin / R1.ymin R3.ymax = R2.ymax / R1.ymax
R1 / t	Divides a rectangle by 4 Lua array elements. For example, R2 = R / t is equivalent to R2 = NewRect() R2.xmin = R1.xmin / t[0] R2.xmax = R1.xmax / t[1] R2.ymin = R1.ymin / t[2] R2.ymax = R1.ymax / t[3]
R1 / P	Divides a rectangle by a CPoint. For example, R2 = R / P is equivalent to R2 = NewRect() R2.xmin = R.xmin / P.x R2.xmax = R.xmax / P.x R2.ymin = R.ymin / P.y R2.ymax = R.ymax / P.y
R1 / num	Divides a rectangle by a number. For example, R2 = R / 0.5 is equivalent to R2 = NewRect() R2.xmin = R.xmin / 0.5 R2.xmax = R.xmax / 0.5 R2.ymin = R.ymin / 0.5 R2.ymax = R.ymax / 0.5

Modulus (Remainder)

R1 % R2	Calculates the remainder of dividing a rectangle by another rectangle. For example, R3 = R1 % R2 is equivalent to R3 = NewRect( R1 ) R3.xmin = R2.xmin % R1.xmin R3.xmax = R2.xmax % R1.xmax R3.ymin = R2.ymin % R1.ymin R3.ymax = R2.ymax % R1.ymax
R1 % t	Calculates the remainder of dividing a rectangle by 4 Lua array elements. For example, R2 = R % t is equivalent to R2 = NewRect() R2.xmin = R1.xmin % t[0] R2.xmax = R1.xmax % t[1] R2.ymin = R1.ymin % t[2] R2.ymax = R1.ymax % t[3]
R1 % P	Calculates the remainder of dividing a rectangle by a CPoint. For example, R2 = R % P is equivalent to R2 = NewRect() R2.xmin = R.xmin % P.x R2.xmax = R.xmax % P.x R2.ymin = R.ymin % P.y R2.ymax = R.ymax % P.y
R1 % num	Calculates the remainder of dividing a rectangle by a number. For example, R2 = R % 0.5 is equivalent to R2 = NewRect() R2.xmin = R.xmin % 0.5 R2.xmax = R.xmax % 0.5 R2.ymin = R.ymin % 0.5 R2.ymax = R.ymax % 0.5

Unary Minus (Negation)

–R	Computes the unary minus (or negative) of the rectangle. For example, R2 = -R is equivalent to R2 = NewRect() R2.xmin = -R.xmin R2.xmax = -R.xmax R2.ymin = -R.ymin R2.ymax = -R.ymax and -R is equivalent to R.xmin = -R.xmin R.xmax = -R.xmax R.ymin = -R.ymin R.ymax = -R.ymax

Comparison

For two rectanges, R1 and R2, this operator returns true if each property of R1 is equal to the corresponding property of R2. For example,

if R2 == R1 then Func() end

is equivalent to

if R2.xmin == R1.xmin and R2.xmax == R1.xmax and

R2.ymin == R1.ymin and R2.ymax == R1.ymax then

Func()

end

For two rectanges, R1 and R2, this operator returns true if each property of R1 is less than or equal to the corresponding property of R2. For example,

if R2 <= R1 then Func() end

is equivalent to

if R2.xmin <= R1.xmin and R2.xmax <= R1.xmax and

R2.ymin <= R1.ymin and R2.ymax <= R1.ymax then

Func()

end

For two rectanges, R1 and R2, this operator returns true if each property of R1 is less than the corresponding property of R2. For example,

if R2 < R1 then Func() end

is equivalent to

if R2.xmin < R1.xmin and R2.xmax < R1.xmax and

R2.ymin < R1.ymin and R2.ymax < R1.ymax then

Func()

end