VectorArithmetic
Overview
Extending CGPoint
, CGSize
and CGVector
with the protocols
VectorOperatable
& VectorArithmetic
Handles some of the Swift bugs related to architecture differences.
Just want to point out that Apple themselves uses CGPoint throughout UIKit for velocity and other vectors. So remember that when you see myPoint + myOtherPoint * 2
Dependency
To get better interoperability between different numerical types use
Usage
Math Functions
let vector = CGVector(20, 5.5)
let point = CGPoint(x: 5, y: 5)
vector.angleInRadians // -1.30243011588899
vector.magnitude // 20.7424685126915
vector.length // synonym to magnitude
vector.lengthSquared // 430.25
vector.dotProduct(point) // 127.5
vector.crossProduct(point) // -72.5
vector.distanceTo(point) // 15.0083310198036
vector.reversed // {dx -20.0, dy -5.5}
vector.normalized // {dx 0.96420539280379, dy 0.265156483021042}
vector.limited(20) // {dx 19.2841078560758, dy 5.30312966042085}
vector.scaled(20) // synonym to limited()
vector.angled(90) // {dx -9.29415287392715, dy 18.5436976451859}
Operators
var point:CGPoint = CGPoint(x: 2.0, y: 2.0)
var vector:CGVector = CGVector(horizontal: 2.0, vertical: 2.0)
point = point + vector
point += vector
point = point - vector
point -= vector
point = point * vector
point *= vector
point = point / vector
point /= vector
vector = vector * 4.5
vector *= 20.5
vector = vector / 2.0
vector /= 2.0
Equatable and Comparable
point == vector
point != vector
point < vector
point <= vector
point > vector
point >= vector
Generic initializer
let point = CGPoint(horizontal:2.0,vertical:2.0)
let vector = CGVector(horizontal:2.0,vertical:2.0)
let yourStruct = YourStruct(horizontal:2.0,vertical:2.0)
Type constraints
class Boid<T:VectorOperatable, U:VectorOperatable> {
var position = T(horizontal: 2.0, vertical: 2.5)
var velocity = U(horizontal: 2.0, vertical: 2.5)
}
let boid = Boid<CGPoint, CGVector>()
boid.position = CGPointZero
boid.velocity = CGVectorMake(20, 20)
boid.velocity > boid.position // True
Extending
Equatable and Comparable
protocol VectorOperatable {
init(horizontal:Double,vertical:Double)
var horizontal:Double { get set }
var vertical:Double { get set }
}
Math Functions
protocol VectorArithmetic : VectorOperatable {
var angleInRadians:Double {get}
var magnitude:Double {get}
var length:Double {get}
var lengthSquared:Double {get}
func dotProduct <T : VectorArithmetic>(vector:T) -> Double
func distanceTo <T : VectorArithmetic>(vector:T) -> Double
var reversed:Self {get}
var normalized:Self {get}
func limited(scalar:Double) -> Self
func scaled(scalar:Double) -> Self
func angled(scalar:Double) -> Self
}
###Contact
If you end up using VectorArithmetic in a project, I'd love to hear about it.
email: seivan.heidari@icloud.com
twitter: @seivanheidari
License
VectorArithmetic is © 2014 Seivan and may be freely
distributed under the MIT license.
See the LICENSE.md
file.