refactor

vec.ts

@@ -0,0 +1,59 @@
+import { Point } from "./common";
+
+function trueMod(v: number, max: number): number {
+  return ((v % max) + max) % max;
+}
+
+export default class Vec2d implements Point {
+  x: number;
+  y: number;
+
+  constructor(x: number, y: number) {
+    this.x = x;
+    this.y = y;
+  }
+
+  static random(maxX: number, maxY: number) {
+    return new Vec2d(Math.random() * maxX, Math.random() * maxY);
+  }
+
+  toString() {
+    return `[${this.x}, ${this.y}]`;
+  }
+
+  scale(scalar: number): Vec2d {
+    return new Vec2d(this.x * scalar, this.y * scalar);
+  }
+
+  add(other: Vec2d): Vec2d {
+    return new Vec2d(this.x + other.x, this.y + other.y);
+  }
+
+  sub(other: Vec2d): Vec2d {
+    return new Vec2d(this.x - other.x, this.y - other.y);
+  }
+
+  length(): number {
+    return Math.sqrt(this.x * this.x + this.y * this.y);
+  }
+
+  distance(other: Vec2d): number {
+    return this.sub(other).length();
+  }
+
+  lerp(other: Vec2d, t: number): Vec2d {
+    // (1-t)*A + B*t
+    return this.scale(1 - t).add(other.scale(t));
+  }
+
+  clamp(min: Vec2d, max: Vec2d): Vec2d {
+    return new Vec2d(
+      Math.min(Math.max(this.x, min.x), max.x),
+      Math.min(Math.max(this.y, min.y), max.y)
+    );
+  }
+
+  wrap(bounds: Vec2d) {
+    return new Vec2d(trueMod(this.x, bounds.x), trueMod(this.y, bounds.y));
+  }
+}