feat: add raycasts

src/vec.py

@@ -24,6 +24,9 @@ class Vec:
     def __truediv__(self, value: float) -> Vec:
         return Vec(self.x / value, self.y / value)
 
+    def __neg__(self) -> Vec:
+        return Vec(-self.x, -self.y)
+
     def dot(self, other: Vec) -> float:
         return self.x * other.x + self.y * other.y