added reviewed changes

mesa/visualization/mpl_space_drawing.py

@@ -10,6 +10,7 @@
 import itertools
 import warnings
 from collections.abc import Callable
+from itertools import pairwise
 from typing import Any
 
 import networkx as nx
@@ -346,7 +347,7 @@ def draw_hex_grid(
 
     def setup_hexmesh(width, height):
         """Helper function for creating the hexmesh with unique edges."""
-        edges = set()
+        edges = []
         size = 1.0
         x_spacing = np.sqrt(3) * size
         y_spacing = 1.5 * size
@@ -374,18 +375,15 @@ def get_hex_vertices(
             vertices = get_hex_vertices(x, y)
 
             # Edge logic, connecting each vertex to the next
-            for i in range(len(vertices)):
-                v1 = vertices[i]
-                v2 = vertices[(i + 1) % len(vertices)]
-
-                # Sort vertices to ensure consistent edge representation
+            for v1, v2 in pairwise(vertices + [vertices[0]]):
+                # Sort vertices to ensure consistent edge representation and avoid duplicates.
                 edge = tuple(sorted([tuple(np.round(v1, 6)), tuple(np.round(v2, 6))]))
-                edges.add(edge)
+                if edge not in edges:
+                    edges.append(edge)
 
-        # Convert to LineCollection format
-        edges_list = [np.array(edge) for edge in edges]
+        # Return LineCollection for hexmesh
         return LineCollection(
-            edges_list, linestyle=":", color="black", linewidth=1, alpha=1
+            edges, linestyle=":", color="black", linewidth=1, alpha=1
         )
 
     if draw_grid: