Move grid snapping to hook and added math for hex snapping

src/helpers/Vector3.js

@@ -0,0 +1,55 @@
+/**
+ * Vector class with x, y, z and static helper methods
+ */
+class Vector3 {
+  /**
+   * @type {number} x - X component of the vector
+   */
+  x;
+  /**
+   * @type {number} y - Y component of the vector
+   */
+  y;
+  /**
+   * @type {number} z - Z component of the vector
+   */
+  z;
+
+  /**
+   * @param {number} x
+   * @param {number} y
+   * @param {number} z
+   */
+  constructor(x, y, z) {
+    this.x = x;
+    this.y = y;
+    this.z = z;
+  }
+
+  /**
+   * Round a Vector3 to the nearest integer while maintaining x + y + z = 0
+   * @param {Vector3} cube
+   * @returns {Vector3}
+   */
+  static cubeRound(cube) {
+    var rX = Math.round(cube.x);
+    var rY = Math.round(cube.y);
+    var rZ = Math.round(cube.z);
+
+    var xDiff = Math.abs(rX - cube.x);
+    var yDiff = Math.abs(rY - cube.y);
+    var zDiff = Math.abs(rZ - cube.z);
+
+    if (xDiff > yDiff && xDiff > zDiff) {
+      rX = -rY - rZ;
+    } else if (yDiff > zDiff) {
+      rY = -rX - rZ;
+    } else {
+      rZ = -rX - rY;
+    }
+
+    return new Vector3(rX, rY, rZ);
+  }
+}
+
+export default Vector3;