Move edt as part of track asset

examples/create_edt.py

@@ -0,0 +1,41 @@
+from f110_gym.envs.track import Track
+from scipy.ndimage import distance_transform_edt as edt
+import numpy as np
+
+DEFAULT_MAP_NAMES = [
+    "Austin",
+    "BrandsHatch",
+    "Budapest",
+    "Catalunya",
+    "Hockenheim",
+    "IMS",
+    "Melbourne",
+    "MexicoCity",
+    "Montreal",
+    "Monza",
+    "MoscowRaceway",
+    "Nuerburgring",
+    "Oschersleben",
+    "Sakhir",
+    "SaoPaulo",
+    "Sepang",
+    "Shanghai",
+    "Silverstone",
+    "Sochi",
+    "Spa",
+    "Spielberg",
+    "YasMarina",
+    "Zandvoort",
+]
+
+for track_name in DEFAULT_MAP_NAMES:
+    track = Track.from_track_name(track_name)
+    occupancy_map = track.occupancy_map
+    resolution = track.spec.resolution
+
+    dt = resolution * edt(occupancy_map)
+
+    # saving
+    np.save(track.filepath, dt)
+
+    track_wedt = Track.from_track_name(track_name)

f1tenth_gym/envs/laser_models.py

@@ -488,7 +488,10 @@ def set_map(self, map: str | Track):
         self.orig_c = np.cos(self.origin[2])
 
         # get the distance transform
-        self.dt = get_dt(self.map_img, self.map_resolution)
+        if self.track.edt is not None:
+            self.dt = self.track.edt
+        else:
+            self.dt = get_dt(self.map_img, self.map_resolution)
 
         return True
 

f1tenth_gym/envs/track/track.py

@@ -2,6 +2,7 @@
 import pathlib
 from dataclasses import dataclass
 from typing import Tuple, Optional
+import os
 
 import numpy as np
 import yaml
@@ -31,6 +32,7 @@ class Track:
     filepath: str
     ext: str
     occupancy_map: np.ndarray
+    edt: np.ndarray
     centerline: Raceline
     raceline: Raceline
 
@@ -40,6 +42,7 @@ def __init__(
         filepath: str,
         ext: str,
         occupancy_map: np.ndarray,
+        edt: Optional[np.ndarray] = None,
         centerline: Optional[Raceline] = None,
         raceline: Optional[Raceline] = None,
     ):
@@ -56,6 +59,8 @@ def __init__(
             file extension of the track image file
         occupancy_map : np.ndarray
             occupancy grid map
+        edt : np.ndarray
+            distance transform of the map
         centerline : Raceline, optional
             centerline of the track, by default None
         raceline : Raceline, optional
@@ -65,6 +70,7 @@ def __init__(
         self.filepath = filepath
         self.ext = ext
         self.occupancy_map = occupancy_map
+        self.edt = edt
         self.centerline = centerline
         self.raceline = raceline
 
@@ -125,6 +131,18 @@ def from_track_name(track: str):
             occupancy_map[occupancy_map <= 128] = 0.0
             occupancy_map[occupancy_map > 128] = 255.0
 
+            # if exists and it has been created for the current map image, load edt
+            map_filepath = (track_dir / map_filename).absolute()
+            track_filepath = map_filepath.with_suffix("")
+            edt_filepath = track_dir / f"{track}_map.npy"
+            if edt_filepath.exists() and os.path.getmtime(edt_filepath) >= os.path.getmtime(map_filepath):
+                edt = np.load(track_dir / f"{track}_map.npy")
+            else:
+                from scipy.ndimage import distance_transform_edt as edt
+                resolution = track_spec.resolution
+                edt = resolution * edt(occupancy_map)
+                np.save(track_filepath, edt)
+
             # if exists, load centerline
             if (track_dir / f"{track}_centerline.csv").exists():
                 centerline = Raceline.from_centerline_file(
@@ -146,6 +164,7 @@ def from_track_name(track: str):
                 filepath=str((track_dir / map_filename.stem).absolute()),
                 ext=map_filename.suffix,
                 occupancy_map=occupancy_map,
+                edt=edt,
                 centerline=centerline,
                 raceline=raceline,
             )

f1tenth_gym/envs/track/utils.py

@@ -24,7 +24,7 @@ def find_track_dir(track_name: str) -> pathlib.Path:
     FileNotFoundError
         if no map directory matching the track name is found
     """
-    map_dir = pathlib.Path(__file__).parent.parent.parent.parent / "maps"
+    map_dir = pathlib.Path(__file__).parent.parent.parent.parent.parent / "maps"
 
     if not (map_dir / track_name).exists():
         print("Downloading Files for: " + track_name)

tests/test_track.py

@@ -1,3 +1,5 @@
+import datetime
+import os
 import pathlib
 import time
 import unittest
@@ -138,3 +140,29 @@ def test_download_racetrack(self):
         # rename the backup track dir to its original name
         track_backup_dir = find_track_dir(tmp_dir.stem)
         track_backup_dir.rename(track_dir)
+
+    def test_edt_update(self):
+        """
+        Test the re-creation of the edt if the map modification time is more recent.
+        """
+        track = Track.from_track_name("Spielberg")
+
+        # set the map image modification/access time to now
+        now = datetime.datetime.now()
+        dt_epoch = now.timestamp()
+        map_filepath = pathlib.Path(track.filepath).parent / track.spec.image
+        os.utime(map_filepath, (dt_epoch, dt_epoch))
+
+        # check the edt modification time is now < the map image time
+        edt_filepath = map_filepath.with_suffix(".npy")
+        self.assertTrue(os.path.getmtime(map_filepath) > os.path.getmtime(edt_filepath),
+                         f"expected the map image modification time to be > the edt modification time")
+
+        # this should force the edt to be recomputed
+        # check the edt modification time is not > the map image time
+        track2 = Track.from_track_name("Spielberg")
+        self.assertTrue(os.path.getmtime(map_filepath) < os.path.getmtime(edt_filepath),
+                        f"expected the map image modification time to be > the edt modification time")
+
+        # check consistency in the maps edts
+        self.assertTrue(np.allclose(track.edt, track2.edt), f"expected the same edt transform for {track.spec.name}")