Improve visualizations

examples/01_simple_route.py

@@ -49,7 +49,7 @@ def main() -> None:
         print("Failed to route.")
 
     # 5. Visualize
-    fig, ax = plot_routing_results(results, [obstacle], bounds)
+    fig, ax = plot_routing_results(results, [obstacle], bounds, netlist=netlist)
     fig.savefig("examples/simple_route.png")
     print("Saved plot to examples/simple_route.png")
 

examples/02_congestion_resolution.py

@@ -45,7 +45,7 @@ def main() -> None:
             print(f"  {nid}: valid={res.is_valid}, collisions={res.collisions}")
 
     # 5. Visualize
-    fig, ax = plot_routing_results(results, [], bounds)
+    fig, ax = plot_routing_results(results, [], bounds, netlist=netlist)
     fig.savefig("examples/congestion.png")
     print("Saved plot to examples/congestion.png")
 

examples/03_locked_paths.py

@@ -59,16 +59,18 @@ def main() -> None:
         print("Failed to route secondary net.")
 
     # 5. Visualize
-    # Combine results for plotting
+    # Combine results and netlists for plotting
     all_results = {**results1, **results2}
+    all_netlists = {**netlist_phase1, **netlist_phase2}
 
     # Note: 'critical_net' is now in engine.static_obstacles internally, 
     # but for visualization we plot it from the result object to see it clearly.
     # We pass an empty list for 'static_obstacles' to plot_routing_results 
     # because we want to see the path colored, not grayed out as an obstacle.
 
-    fig, ax = plot_routing_results(all_results, [], bounds)
+    fig, ax = plot_routing_results(all_results, [], bounds, netlist=all_netlists)
     fig.savefig("examples/locked.png")
+
     print("Saved plot to examples/locked.png")
 
 

examples/04_sbends_and_radii.py

@@ -61,7 +61,7 @@ def main() -> None:
         print(f"{nid}: {status}, collisions={res.collisions}")
 
     # 6. Visualize
-    fig, ax = plot_routing_results(results, [], bounds)
+    fig, ax = plot_routing_results(results, [], bounds, netlist=netlist)
     fig.savefig("examples/sbends_radii.png")
     print("Saved plot to examples/sbends_radii.png")
 

inire/utils/visualization.py

@@ -3,12 +3,14 @@ from __future__ import annotations
 from typing import TYPE_CHECKING
 
 import matplotlib.pyplot as plt
+import numpy as np
 
 if TYPE_CHECKING:
     from matplotlib.axes import Axes
     from matplotlib.figure import Figure
     from shapely.geometry import Polygon
 
+    from inire.geometry.primitives import Port
     from inire.router.pathfinder import RoutingResult
 
 
@@ -16,6 +18,7 @@ def plot_routing_results(
     results: dict[str, RoutingResult],
     static_obstacles: list[Polygon],
     bounds: tuple[float, float, float, float],
+    netlist: dict[str, tuple[Port, Port]] | None = None,
 ) -> tuple[Figure, Axes]:
     """Plot obstacles and routed paths using matplotlib."""
     fig, ax = plt.subplots(figsize=(10, 10))
@@ -34,7 +37,8 @@ def plot_routing_results(
             color = "red"  # Highlight failing nets
 
         label_added = False
-        for comp in res.path:
+        for j, comp in enumerate(res.path):
+            # 1. Plot geometry
             for poly in comp.geometry:
                 # Handle both Polygon and MultiPolygon (e.g. from SBend)
                 geoms = [poly] if hasattr(poly, "exterior") else poly.geoms
@@ -43,6 +47,26 @@ def plot_routing_results(
                     ax.fill(x, y, alpha=0.7, fc=color, ec="black", label=net_id if not label_added else "")
                     label_added = True
 
+            # 2. Plot subtle port orientation arrow for internal ports
+            # (Every segment's end_port except possibly the last one if it matches target)
+            p = comp.end_port
+            rad = np.radians(p.orientation)
+            u = np.cos(rad)
+            v = np.sin(rad)
+
+            # Internal ports get smaller, narrower, semi-transparent arrows
+            ax.quiver(p.x, p.y, u, v, color="black", scale=40, width=0.003, alpha=0.3, pivot="tail", zorder=4)
+
+        # 3. Plot main arrows for netlist ports (if provided)
+        if netlist and net_id in netlist:
+            start_p, target_p = netlist[net_id]
+            for p in [start_p, target_p]:
+                rad = np.radians(p.orientation)
+                u = np.cos(rad)
+                v = np.sin(rad)
+                # Netlist ports get prominent arrows
+                ax.quiver(p.x, p.y, u, v, color="black", scale=25, width=0.005, pivot="tail", zorder=6)
+
     ax.set_xlim(bounds[0], bounds[2])
     ax.set_ylim(bounds[1], bounds[3])
     ax.set_aspect("equal")
@@ -51,5 +75,5 @@ def plot_routing_results(
     handles, labels = ax.get_legend_handles_labels()
     if labels:
         ax.legend()
-    plt.grid(True)
+    ax.grid(alpha=0.6)
     return fig, ax