diff --git a/src/tools/visualization.py b/src/tools/visualization.py
index 46079a1..2011a59 100644
--- a/src/tools/visualization.py
+++ b/src/tools/visualization.py
@@ -15,17 +15,16 @@ class Window:
         self.__canvas.bind("<ButtonPress-1>", self._scroll_start)
         self.__canvas.bind("<B1-Motion>", self._scroll_move)
 
-        self.__boundary_box = [0, 0, 0, 0]
+        self.__boundary_box = [None, None, None, None]
 
     def _update_boundaries(self, coord: Coordinate | tuple[int, int]) -> None:
-        if coord[0] < self.__boundary_box[0]:
+        if self.__boundary_box[0] is None or coord[0] < self.__boundary_box[0]:
             self.__boundary_box[0] = coord[0]
-        elif coord[0] > self.__boundary_box[2]:
+        if self.__boundary_box[2] is None or coord[0] > self.__boundary_box[2]:
             self.__boundary_box[2] = coord[0]
-
-        if coord[1] < self.__boundary_box[1]:
+        if self.__boundary_box[1] is None or coord[1] < self.__boundary_box[1]:
             self.__boundary_box[1] = coord[1]
-        elif coord[1] > self.__boundary_box[3]:
+        if self.__boundary_box[3] is None or coord[1] > self.__boundary_box[3]:
             self.__boundary_box[3] = coord[1]
 
     def _zoom(self, event: tk.Event) -> None:
@@ -38,18 +37,20 @@ class Window:
     def _scroll_move(self, event: tk.Event) -> None:
         self.__canvas.scan_dragto(event.x, event.y, gain=1)
 
-    def clear(self) -> None:
+    def clear(self, keep_boundaries: bool = False) -> None:
         self.__canvas.delete(tk.ALL)
+        if not keep_boundaries:
+            self.__boundary_box = [None, None, None, None]
 
     def draw_line(self, line: Line) -> None:
         self.__canvas.create_line(line.start.x, line.start.y, line.end.x, line.end.y, fill=self.fg_color, width=1)
         self._update_boundaries(line.start)
         self._update_boundaries(line.end)
 
-    def realign(self, padding: int = 10) -> None:
-        if self.__boundary_box[0] < 0:
+    def realign(self, padding: int = 1) -> None:
+        if self.__boundary_box[0] is not None and self.__boundary_box[0] < 0:
             self.__canvas.move(tk.ALL, abs(self.__boundary_box[0]) + padding, 0)
-        if self.__boundary_box[1] < 0:
+        if self.__boundary_box[1] is not None and self.__boundary_box[1] < 0:
             self.__canvas.move(tk.ALL, 0, abs(self.__boundary_box[1]) + padding)
         dim_x = self.__boundary_box[2] - self.__boundary_box[0] + 2 * padding
         dim_y = self.__boundary_box[3] - self.__boundary_box[1] + 2 * padding