PyAPI: add optional filter argument to KDTree.find

tests/python/bl_pyapi_mathutils.py

@@ -240,17 +240,23 @@ class QuaternionTesting(unittest.TestCase):
 
 
 class KDTreeTesting(unittest.TestCase):
-
     @staticmethod
-    def kdtree_create_grid_3d(tot):
-        k = kdtree.KDTree(tot * tot * tot)
+    def kdtree_create_grid_3d_data(tot):
         index = 0
         mul = 1.0 / (tot - 1)
         for x in range(tot):
             for y in range(tot):
                 for z in range(tot):
-                    k.insert((x * mul, y * mul, z * mul), index)
+                    yield (x * mul, y * mul, z * mul), index
                     index += 1
+
+    @staticmethod
+    def kdtree_create_grid_3d(tot, *, filter_fn=None):
+        k = kdtree.KDTree(tot * tot * tot)
+        for co, index in KDTreeTesting.kdtree_create_grid_3d_data(tot):
+            if (filter_fn is not None) and (not filter_fn(co, index)):
+                continue
+            k.insert(co, index)
         k.balance()
         return k
 
@@ -327,6 +333,49 @@ class KDTreeTesting(unittest.TestCase):
         ret = k.find_n((1.0,) * 3, tot)
         self.assertEqual(len(ret), tot)
 
+    def test_kdtree_grid_filter_simple(self):
+        size = 10
+        k = self.kdtree_create_grid_3d(size)
+
+        # filter exact index
+        ret_regular = k.find((1.0,) * 3)
+        ret_filter = k.find((1.0,) * 3, filter=lambda i: i == ret_regular[1])
+        self.assertEqual(ret_regular, ret_filter)
+        ret_filter = k.find((-1.0,) * 3, filter=lambda i: i == ret_regular[1])
+        self.assertEqual(ret_regular[:2], ret_filter[:2])  # ignore distance
+
+    def test_kdtree_grid_filter_pairs(self):
+        size = 10
+        k_all = self.kdtree_create_grid_3d(size)
+        k_odd = self.kdtree_create_grid_3d(size, filter_fn=lambda co, i: (i % 2) == 1)
+        k_evn = self.kdtree_create_grid_3d(size, filter_fn=lambda co, i: (i % 2) == 0)
+
+        samples = 5
+        mul = 1 / (samples - 1)
+        for x in range(samples):
+            for y in range(samples):
+                for z in range(samples):
+                    co = (x * mul, y * mul, z * mul)
+
+                    ret_regular = k_odd.find(co)
+                    self.assertEqual(ret_regular[1] % 2, 1)
+                    ret_filter = k_all.find(co, lambda i: (i % 2) == 1)
+                    self.assertEqual(ret_regular, ret_filter)
+
+                    ret_regular = k_evn.find(co)
+                    self.assertEqual(ret_regular[1] % 2, 0)
+                    ret_filter = k_all.find(co, lambda i: (i % 2) == 0)
+                    self.assertEqual(ret_regular, ret_filter)
+
+
+        # filter out all values (search odd tree for even values and the reverse)
+        co = (0,) * 3
+        ret_filter = k_odd.find(co, lambda i: (i % 2) == 0)
+        self.assertEqual(ret_filter[1], None)
+
+        ret_filter = k_evn.find(co, lambda i: (i % 2) == 1)
+        self.assertEqual(ret_filter[1], None)
+
     def test_kdtree_invalid_size(self):
         with self.assertRaises(ValueError):
             kdtree.KDTree(-1)
@@ -342,6 +391,21 @@ class KDTreeTesting(unittest.TestCase):
         with self.assertRaises(RuntimeError):
             k.find(co)
 
+    def test_kdtree_invalid_filter(self):
+        k = kdtree.KDTree(1)
+        k.insert((0,) * 3, 0)
+        k.balance()
+        # not callable
+        with self.assertRaises(TypeError):
+            k.find((0,) * 3, filter=None)
+        # no args
+        with self.assertRaises(TypeError):
+            k.find((0,) * 3, filter=lambda: None)
+        # bad return value
+        with self.assertRaises(ValueError):
+            k.find((0,) * 3, filter=lambda i: None)
+
+
 if __name__ == '__main__':
     import sys
     sys.argv = [__file__] + (sys.argv[sys.argv.index("--") + 1:] if "--" in sys.argv else [])