Example for weighted image-map

.gitignore

@@ -65,5 +65,5 @@ target/
 # python virtual env
 venv/
 
-examples/out.png
-examples/*.perf
+examples/*/out.png
+examples/*/*.perf

examples/README.md

@@ -1,10 +1,30 @@
 # Example implementations using python-pathfinding
 
-## *image_pathfinding.py*
-Create a map from and image and run a path finding algorithm on it (requires PIL/Pillow).
+## Image Simple
 
-You can all it with an input and output file like this:
+Create a map from an image and run a path finding algorithm on it. Requires: `pip install pillow`.
+
+You can run it with an input and output file like this:
 ```
-cd examples/
+cd examples/image-simple/
 python3 image_pathfinding.py -i map.png -o foo.png
-```
+```
+
+----
+
+## Image Weighted
+
+Create a map from and image and run a path finding algorithm on it. Requires: `pip install pillow`.
+
+It maps specific colors to their weights. Make sure to update the value-mapping for your custom input-maps!
+
+You can run it with an input and output file like this:
+
+```
+cd examples/image-weighted/
+python3 image_pathfinding.py -i map.png -o foo.png
+```
+
+To add some randomization to the weights - you can use the `-r` flag: `python3 image_pathfinding.py -i map.png -o foo.png -r 0.5`
+
+Note: The terrain-map was generated with OpenSimplex-noise via [this Python script](https://github.com/O-X-L/opensimplex).

examples/image_pathfinding.py → examples/image-simple/image_pathfinding.py

@@ -35,11 +35,13 @@ def pixel_walkable(pixel, x, y):
     return any([p > 50 for p in pixel])  # darker pixel are not walkable
 
 
-def main(filename_map: str = MAP_FILE, filename_out: str = OUT_FILE):
+def main(filename_map: str = MAP_FILE, filename_out: str = OUT_FILE, diagonal_movement: bool = False):
     nodes = []
     if not Path(filename_map).exists():
         print(f'File {filename_map} does not exist.')
         return
+
+    print('Parsing map..')
     with Image.open(filename_map) as im:
         width, height = im.size
         for y in range(height):
@@ -56,11 +58,14 @@ def main(filename_map: str = MAP_FILE, filename_out: str = OUT_FILE):
         end = grid.node(*_goal)
         start = grid.node(*_start)
 
-        finder = AStarFinder(diagonal_movement=DiagonalMovement.never)
+        print('Finding optimal path..')
+        finder = AStarFinder(diagonal_movement=DiagonalMovement.always if diagonal_movement else DiagonalMovement.never)
         path, runs = finder.find_path(start, end, grid)
 
         # print(grid.grid_str(path=path, end=end, start=start))
-        print('iterations:', runs, 'path length:', len(path))
+        print(f'iterations: {runs:_} path length: {len(path):_}')
+
+        print('Saving image..')
         out = im.copy()
         for p in path[1:-1]:
             out.putpixel((p.x, p.y), (255, 165, 0))
@@ -79,5 +84,9 @@ def main(filename_map: str = MAP_FILE, filename_out: str = OUT_FILE):
         '-o', '--filename_out',
         help='output file',
         default=OUT_FILE)
+    parser.add_argument(
+        '-d', '--diagonal-movement',
+        help='allow for diagonal movement',
+        action='store_true')
 
     main(**vars(parser.parse_args()))

examples/image-weighted/image_pathfinding.py

@@ -0,0 +1,108 @@
+# Create a Map from an image
+import os
+from pathlib import Path
+import argparse
+from random import uniform as random_float
+
+# Pillow
+from PIL import Image
+
+# pathfinding
+from pathfinding.core.diagonal_movement import DiagonalMovement
+from pathfinding.core.grid import Grid
+from pathfinding.finder.a_star import AStarFinder
+
+
+# image file with the map
+BASE_PATH = Path(os.path.dirname(__file__))
+MAP_FILE = BASE_PATH / "map.png"
+OUT_FILE = BASE_PATH / "out.png"
+
+# this script searches for specific colors in RGB-format
+COLOR_START = (255, 255, 0)  # yellow
+COLOR_END = (255, 0, 0)  # red
+COLOR_PATH = (255, 165, 0)  # orange
+COLOR_WEIGHT_MAPPING = {
+    (0, 62, 178): 10,  # deep water
+    (9, 82, 198): 3,  # water
+    (254, 224, 179): 1,  # sand
+    (9, 120, 93): 2,  # grass
+    (10, 107, 72): 3,  # bushes
+    (11, 94, 51): 4,  # forest
+    (140, 142, 123): 5,  # hills
+    (160, 162, 143): 10,  # alpine
+    (53, 54, 68): 15,  # steep cliff
+    (255, 255, 255): 10,  # snow
+}
+
+
+def main(
+        filename_map: str = MAP_FILE, filename_out: str = OUT_FILE,
+        weight_randomization: float = 0, diagonal_movement: bool = False,
+):
+    nodes = []
+    if not Path(filename_map).exists():
+        print(f'File {filename_map} does not exist.')
+        return
+
+    print('Parsing map..')
+    with Image.open(filename_map) as im:
+        width, height = im.size
+        for y in range(height):
+            nodes.append([])
+            for x in range(width):
+                pixel = im.getpixel((x, y))
+                weight = COLOR_WEIGHT_MAPPING.get(pixel, 1)
+
+                if weight_randomization != 0:
+                    weight += random_float(0, weight_randomization)
+
+                nodes[y].append(weight)
+
+                if pixel == COLOR_END:
+                    _goal = (x, y)
+                elif pixel == COLOR_START:
+                    _start = (x, y)
+
+        grid = Grid(matrix=nodes)
+        end = grid.node(*_goal)
+        start = grid.node(*_start)
+
+        print('Finding optimal path..')
+        finder = AStarFinder(diagonal_movement=DiagonalMovement.always if diagonal_movement else DiagonalMovement.never)
+        path, runs = finder.find_path(start, end, grid)
+
+        # print(grid.grid_str(path=path, end=end, start=start))
+        print(f'iterations: {runs:_} path length: {len(path):_}')
+
+        print('Saving image..')
+        out = im.copy()
+        for p in path[1:-1]:
+            out.putpixel((p.x, p.y), COLOR_PATH)
+        out.save(filename_out)
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(
+        prog='image_pathfinding',
+        description='find a path in an image from a yellow pixel (rgb: 255,255,0) to a red one (rgb: 255,0,0) '
+                    'with weighted-tiles')
+    parser.add_argument(
+        '-i', '--filename_map',
+        help='input file',
+        default=MAP_FILE)
+    parser.add_argument(
+        '-o', '--filename_out',
+        help='output file',
+        default=OUT_FILE)
+    parser.add_argument(
+        '-r', '--weight-randomization',
+        help='how much randomization should be added to the tile-weights (disabled by default)',
+        type=float,
+        default=0)
+    parser.add_argument(
+        '-d', '--diagonal-movement',
+        help='allow for diagonal movement',
+        action='store_true')
+
+    main(**vars(parser.parse_args()))