account for rotation when moving the crop region

packages/math/vector.ts

@@ -139,3 +139,10 @@ export const vectorNormalize = (v: Vector): Vector => {
 
   return vector(v[0] / m, v[1] / m);
 };
+
+/**
+ * Project the first vector onto the second vector
+ */
+export const vectorProjection = (a: Vector, b: Vector) => {
+  return vectorScale(b, vectorDot(a, b) / vectorDot(b, b));
+};