feat(vectors): Added Vector2 class

Added a basic implementation for a 2D vector class

src/common.ts

@@ -0,0 +1 @@
+export const EPSILON = 0.00001

src/ts-vector-math.ts

@@ -1,4 +1,4 @@
 // Import here Polyfills if needed. Recommended core-js (npm i -D core-js)
 // import "core-js/fn/array.find"
 // ...
-export default class DummyClass {}
+export * from './vec2'

src/vec2.ts

@@ -0,0 +1,32 @@
+import { EPSILON } from './common'
+
+export class Vector2 {
+  public x: number
+  public y: number
+  get xy(): number[] {
+    return [this.x, this.y]
+  }
+  set xy(values: number[]) {
+    this.x = values[0]
+    this.y = values[1]
+  }
+  constructor(values?: number[]) {
+    if (values) {
+      this.xy = values
+    }
+  }
+  copy(dest?: Vector2): Vector2 {
+    if (!dest) dest = new Vector2()
+    dest.xy = this.xy
+    return dest
+  }
+  equals(other: Vector2, threshold = EPSILON): boolean {
+    if (Math.abs(this.x - other.x) > threshold) {
+      return false
+    }
+    if (Math.abs(this.y - other.y) > threshold) {
+      return false
+    }
+    return true
+  }
+}

test/ts-vector-math.test.ts

@@ -1,14 +1,67 @@
-import DummyClass from '../src/ts-vector-math'
+import { Vector2 } from '../src/ts-vector-math'
 
 /**
  * Dummy test
  */
-describe('Dummy test', () => {
-  it('works if true is truthy', () => {
-    expect(true).toBeTruthy()
+describe('Vector2', () => {
+  it('is instantiable', () => {
+    expect(new Vector2()).toBeInstanceOf(Vector2)
   })
 
-  it('DummyClass is instantiable', () => {
-    expect(new DummyClass()).toBeInstanceOf(DummyClass)
+  it('can be set through swizzle', () => {
+    let v1 = new Vector2()
+    v1.xy = [1, 2]
+    let v2 = new Vector2()
+    v2.x = 1
+    v2.y = 2
+    expect(v1).toEqual(v2)
+  })
+
+  it('can be retrieved through swizzle', () => {
+    let v1 = new Vector2()
+    v1.xy = [1, 2]
+    expect(v1.xy).toEqual([1, 2])
+  })
+
+  it('detects non-equality', () => {
+    expect(new Vector2([1, 2])).not.toEqual(new Vector2([1, 1]))
+    expect(new Vector2([1, 2])).not.toEqual(new Vector2([2, 2]))
+  })
+
+  it('copies values', () => {
+    let v1 = new Vector2([1, 1])
+    let v2 = v1.copy()
+    v2.xy = [2, 2]
+    expect(v1).not.toEqual(v2)
+  })
+
+  it('copies values to a provided destination', () => {
+    let v1 = new Vector2([1, 1])
+    let v2 = new Vector2([1, 2])
+    let v3 = v1.copy(v2)
+    expect(v2).toEqual(v2)
+    expect(v1).toEqual(v2)
+    expect(v1).toEqual(v3)
+    v3.y = 3
+    expect(v2).toEqual(v3)
+    expect(v1).not.toEqual(v2)
+    expect(v1).not.toEqual(v3)
+  })
+
+  it('tests equality correctly', () => {
+    let v1 = new Vector2([1, 1])
+    let v2 = new Vector2([1, 2])
+    expect(v1.equals(v2)).toBeFalsy()
+    v2.xy = [2, 1]
+    expect(v1.equals(v2)).toBeFalsy()
+    v2.xy = [1, 1]
+    expect(v1.equals(v2)).toBeTruthy()
+  })
+
+  it('tests equality for a given threshold', () => {
+    let v1 = new Vector2([1, 1])
+    let v2 = new Vector2([2, 2])
+    expect(v1.equals(v2)).toBeFalsy()
+    expect(v1.equals(v2, 2)).toBeTruthy()
   })
 })