✨ hexes now only have q and r in the instance

The s coordinate is moved to the prototype (because it's redundant).

src/grid/grid.test.ts

@@ -323,7 +323,7 @@ describe('toJSON()', () => {
 
     expect(result).toStrictEqual({ hexSettings, coordinates })
     expect(JSON.stringify(grid)).toBe(
-      '{"hexSettings":{"dimensions":{"xRadius":10,"yRadius":10},"orientation":"FLAT","origin":{"x":0,"y":0},"offset":1},"coordinates":[{"q":0,"r":0,"s":0},{"q":1,"r":0,"s":-1}]}',
+      '{"hexSettings":{"dimensions":{"xRadius":10,"yRadius":10},"orientation":"FLAT","origin":{"x":0,"y":0},"offset":1},"coordinates":[{"q":0,"r":0},{"q":1,"r":0}]}',
     )
   })
 })

src/hex/hex.test.ts

@@ -11,6 +11,8 @@ describe('creation', () => {
     expect(new Hex([1, 2])).toContain<CubeCoordinates>({ q: 1, r: 2, s: -3 })
     expect(new Hex({ col: 1, row: 2 })).toContain<CubeCoordinates>({ q: 0, r: 2, s: -2 })
     expect(new Hex({ q: 1, r: 2 })).toContain<CubeCoordinates>({ q: 1, r: 2, s: -3 })
+    expect(new Hex({ r: 3, s: 0 })).toContain<CubeCoordinates>({ q: -3, r: 3, s: 0 })
+    expect(new Hex({ q: -3, r: 4, s: -1 })).toContain<CubeCoordinates>({ q: -3, r: 4, s: -1 })
   })
 })
 
@@ -119,15 +121,15 @@ test('implements a point in the prototype', () => {
   expect(Object.hasOwn(hex, 'y')).toBe(false)
 })
 
-test('implements cube coordinates in the instance', () => {
+test('implements axial coordinates in the instance and the s coordinate in the prototype', () => {
   const hex = new Hex([3, -1])
 
   expect(hex.q).toBe(3)
   expect(hex.r).toBe(-1)
   expect(hex.s).toBe(-2)
-  ;['q', 'r', 's'].forEach((coordinate) => {
-    expect(Object.hasOwn(hex, coordinate)).toBe(true)
-  })
+  expect(Object.hasOwn(hex, 'q')).toBe(true)
+  expect(Object.hasOwn(hex, 'r')).toBe(true)
+  expect(Object.hasOwn(hex, 's')).toBe(false)
 })
 
 describe('clone()', () => {

src/hex/hex.ts

@@ -87,16 +87,18 @@ export class Hex
     return hexToPoint(this).y
   }
 
+  get s(): number {
+    return -this.q - this.r
+  }
+
   readonly q: number
   readonly r: number
-  readonly s: number
 
   // todo: also accept q, r and optional s as arguments?
   constructor(coordinates: HexCoordinates = [0, 0]) {
-    const { q, r, s } = toCube(this, coordinates)
+    const { q, r } = toCube(this, coordinates)
     this.q = q
     this.r = r
-    this.s = s
   }
 
   clone<T extends Hex>(newProps: HexCoordinates = this): T {