[*] wrapping for flatXY

src/cartographerFlatXY.js

@@ -1,9 +1,13 @@
 import Cartographer from './cartographer.js';
 
+import * as funky from './funky';
 import {rangeInclusive, invSqrt2} from './utils.js';
 
-import Square from './square.js';
 import Point from './point.js';
+import Square from './square.js';
+
+const makeASquare = ({x, y}) => new Square(x, y);
+const tilePointToSquare = ({tilePoint, pixelPoint}) => ({tilePoint: makeASquare(tilePoint), pixelPoint});
 
 export default class CartographerFlatXY extends Cartographer {
 	constructor(settings) {
@@ -28,7 +32,9 @@ export default class CartographerFlatXY extends Cartographer {
 			'tileToPixel',
 			'pixelToTile',
 
+			'teleport',
 			'inBounds',
+			'enforceBoundries',
 			'boundingBox',
 		].map(method => this[method] = this[method].bind(this));
 	}
@@ -94,7 +100,22 @@ export default class CartographerFlatXY extends Cartographer {
 		return new Square(x, y);
 	}
 
-	inBounds (x, y) {
+	teleport ({x, y}) {
+		if (this.negativeTiles) {
+			x = x % Math.ceil(this.width / 2);
+			y = y % Math.ceil(this.height / 2);
+		}
+		else {
+			x = x % this.width;
+			y = y % this.height;
+			x = x < 0 ? this.width + x : x;
+			y = y < 0 ? this.height + y : y;
+		}
+
+		return new Point(x, y);
+	}
+
+	inBounds ({x, y}) {
 		if (this.negativeTiles) {
 			return (!this.width || Math.abs(x) <= Math.floor(this.width / 2))
 				&& (!this.height || Math.abs(y) <= Math.floor(this.height / 2));
@@ -105,6 +126,12 @@ export default class CartographerFlatXY extends Cartographer {
 		}
 	}
 
+	enforceBoundries ({tilePoint, pixelPoint}) {
+		return this.wrap ? ({tilePoint: this.teleport(tilePoint), pixelPoint}) :
+			this.inBounds(tilePoint) ? ({tilePoint, pixelPoint}) :
+			null;
+	}
+
 	boundingBox(upperLeftPoint, upperRightPoint, lowerLeftPoint, lowerRightPoint) {
 		const upperLeftTile = this.pixelToTile(upperLeftPoint);
 		const lowerRightTile = this.pixelToTile(lowerRightPoint);
@@ -113,9 +140,16 @@ export default class CartographerFlatXY extends Cartographer {
 		const columns = rangeInclusive(upperLeftTile.getX(), upperRightTile.getX());
 		const rows = rangeInclusive(lowerRightTile.getY(), upperLeftTile.getY());
 
-		return columns.map(x => rows.map(y => ({x, y})))
-		.reduce((flat, list) => flat.concat(list), [])
-		.filter(({x, y}) => this.inBounds(x, y))
-		.map(({x, y}) => new Square(x, y));
+		const makeAPoint = x => rows.map(y => ({x, y}));
+		const makeAPointPair = tilePoint => ({tilePoint, pixelPoint: this.tileToPixel(tilePoint)});
+
+		return funky.chain(columns)
+		.map(makeAPoint)
+		.flatten()
+		.map(makeAPointPair)
+		.map(this.enforceBoundries)
+		.compact()
+		.map(tilePointToSquare)
+		.value();
 	}
 }