Few minor tweaks for your tool

.gitignore

@@ -1,4 +1,4 @@
-gpx/*.gpx
+gpx/**/*.gpx
 tiles/
 venv/
 *.png

README.md

@@ -8,6 +8,7 @@ Optimized for cycling activities :bicyclist:
 
 * Minimal Python dependencies (`numpy`+`matplotlib`)
 * Fast (parse 3x faster than `gpxpy.parse`)
+* Supports non Strava GPX tracks
 
 ## Usage
 
@@ -52,7 +53,7 @@ command|output
 ### Requirements
 
 ```
-python>=3.9
+python>=3.8
 numpy>=1.20
 matplotlib>=3.4
 ```

strava_local_heatmap.py

@@ -31,6 +31,8 @@
 from argparse import ArgumentParser, Namespace
 
 # globals
+from typing import Tuple
+
 HEATMAP_MAX_SIZE = (2160, 3840) # maximum heatmap size in pixel
 HEATMAP_MARGIN_SIZE = 32 # margin around heatmap trackpoints in pixel
 
@@ -42,7 +44,7 @@
 OSM_MAX_TILE_COUNT = 100 # maximum number of tiles to download
 
 # functions
-def deg2xy(lat_deg: float, lon_deg: float, zoom: int) -> tuple[float, float]:
+def deg2xy(lat_deg: float, lon_deg: float, zoom: int) -> Tuple[float, float]:
     """Returns OSM coordinates (x,y) from (lat,lon) in degree"""
 
     # from https://wiki.openstreetmap.org/wiki/Slippy_map_tilenames
@@ -53,7 +55,7 @@ def deg2xy(lat_deg: float, lon_deg: float, zoom: int) -> tuple[float, float]:
 
     return x, y
 
-def xy2deg(x: float, y: float, zoom: int) -> tuple[float, float]:
+def xy2deg(x: float, y: float, zoom: int) -> Tuple[float, float]:
     """Returns (lat, lon) in degree from OSM coordinates (x,y)"""
 
     # from https://wiki.openstreetmap.org/wiki/Slippy_map_tilenames
@@ -107,15 +109,25 @@ def download_tile(tile_url: str, tile_file: str) -> bool:
 
 def main(args: Namespace) -> None:
     # read GPX trackpoints
-    gpx_files = glob.glob('{}/{}'.format(args.dir,
-                                         args.filter))
+    gpx_files = glob.glob('{}/**/{}'.format(args.dir,args.filter), recursive=True)
 
     if not gpx_files:
         exit('ERROR no data matching {}/{}'.format(args.dir,
                                                    args.filter))
 
     lat_lon_data = []
 
+    # converting files
+    for gpx_file in gpx_files:
+        print('Converting {}'.format(os.path.basename(gpx_file)))
+        with open(gpx_file, encoding='utf-8') as file:
+            buffer = file.read()
+            buffer = buffer.replace("><", ">\n<")
+            buffer = buffer.replace("\t", "")
+        with open(gpx_file, "w", encoding='utf-8') as file:
+            file.write(buffer)
+
+    # processing files
     for gpx_file in gpx_files:
         print('Reading {}'.format(os.path.basename(gpx_file)))