feat: add units center mass function

.github/workflows/wheels.yml

@@ -187,11 +187,11 @@ jobs:
 
     steps:
       - name: Check out repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
-      - uses: actions/setup-python@v4
+      - uses: actions/setup-python@v5
         with:
           python-version: "3.12"
 

cython_extensions/__init__.py

@@ -43,6 +43,7 @@
 from cython_extensions.units_utils import (
     cy_center,
     cy_closest_to,
+    cy_find_units_center_mass,
     cy_distance_to_squared,
     cy_in_attack_range,
     cy_sorted_by_distance_to,

cython_extensions/units_utils.pyi

@@ -73,6 +73,44 @@ def cy_closest_to(
     """
     ...
 
+def cy_find_units_center_mass(
+    units: Union[Units, list[Unit]], distance: float
+) -> Unit:
+    """Given some units, find the center mass
+
+    Example:
+    ```py
+    from cython_functions import cy_find_units_center_mass
+    from sc2.position import Point2
+
+    center_mass: Point2
+    num_units: int
+    center_mass, num_units = cy_find_units_center_mass(self.units, 10.0)
+    ```
+
+    ```
+    47.8 ms ± 674 µs per loop (mean ± std. dev. of 7 runs, 10 loops each)
+
+    python alternative:
+    322 ms ± 5.2 ms per loop (mean ± std. dev. of 7 runs, 1 loop each)
+    ```
+
+    Parameters
+    ----------
+    units :
+        Position to measure distance from.
+    distance :
+        Collection of units we want to check.
+
+    Returns
+    -------
+    Tuple[Point2, int] :
+        The center mass, and how many units are within `distance`
+        of the center mass.
+
+    """
+    ...
+
 def cy_in_attack_range(
     unit: Unit, units: Union[Units, list[Unit]], bonus_distance: float = 0.0
 ) -> list[Unit]:

cython_extensions/units_utils.pyx

@@ -58,6 +58,35 @@ cpdef object cy_closest_to((float, float) position, object units):
 
     return closest
 
+@boundscheck(False)
+@wraparound(False)
+cpdef tuple cy_find_units_center_mass(units, double distance):
+    cdef:
+        unsigned int max_units_found = 0
+        (double, double) center_position
+        double distance_check = distance * distance
+        list positions = [u.position for u in units]
+        (double, double) pos_1, pos_2
+        unsigned int units_found
+        unsigned int num_units = len(positions)
+        double dist_sq
+        Py_ssize_t i, j
+
+    for i in range(num_units):
+        units_found = 0
+        pos_1 = positions[i]
+        for j in range(num_units):
+            pos_2 = positions[j]
+            dist_sq = cy_distance_to_squared(pos_1, pos_2)
+            if dist_sq < distance_check:
+                units_found += 1
+
+        if units_found > max_units_found:
+            max_units_found = units_found
+            center_position = pos_1
+
+    return center_position, max_units_found
+
 @boundscheck(False)
 @wraparound(False)
 cpdef list cy_in_attack_range(object unit, object units, double bonus_distance = 0.0):

notebooks/building_formation.ipynb

@@ -27,7 +27,7 @@
    "outputs": [],
    "source": [
     "# Change path as needed\n",
-    "MAP_PATH = \"../tests/pickle_data/HardwireAIE.xz\""
+    "MAP_PATH = \"../tests/pickle_data/GresvanAIE.xz\""
    ]
   },
   {