fix(face): Add a method to get Face3D to and from array

ladybug_geometry/geometry2d/polygon.py

@@ -1189,7 +1189,7 @@ def to_dict(self):
                 'vertices': [pt.to_array() for pt in self.vertices]}
 
     def to_array(self):
-        """Get a list of lists where each sub-list represents a Point2D vertex."""
+        """Get a tuple of tuples where each sub-tuple represents a Point2D vertex."""
         return tuple(pt.to_array() for pt in self.vertices)
 
     def _to_bool_poly(self):

ladybug_geometry/geometry3d/face.py

@@ -185,6 +185,22 @@ def from_dict(cls, data):
         return cls(tuple(Point3D.from_array(pt) for pt in data['boundary']),
                    plane, holes)
 
+    @classmethod
+    def from_array(cls, point_array):
+        """Create a Face3D from a nested array of vertex coordinates.
+
+        Args:
+            point_array: A nested array of arrays where each sub-array represents
+                a loop of the Face3D. The first array is the boundary and subsequent
+                arrays represent holes in the Face3D. point arrays. Each sub-array
+                is composed of arrays that each have a length of 3 and denote 3D
+                points that define the face.
+        """
+        boundary = tuple(Point3D(*point) for point in point_array[0])
+        holes = None if len(point_array) == 1 else \
+            tuple(tuple(Point3D(*point) for point in hole) for hole in point_array[1:])
+        return cls(boundary, None, holes)
+
     @classmethod
     def from_extrusion(cls, line_segment, extrusion_vector):
         """Initialize Face3D by extruding a line segment.
@@ -2713,6 +2729,19 @@ def to_dict(self, include_plane=True, enforce_upper_left=False):
                              for hole in self.holes]
         return base
 
+    def to_array(self):
+        """Get Face3D as a nested list of tuples where each sub-tuple represents loop.
+
+        The first loop is always the outer boundary and successive loops represent
+        holes in the face (if they exist). Each sub-tuple is composed of tuples
+        that each have a length of 3 and denote 3D points that define the face.
+        """
+        if self.has_holes:
+            return (tuple(pt.to_array() for pt in self.boundary),) + \
+                tuple(tuple(pt.to_array() for pt in hole) for hole in self.holes)
+        else:
+            return (tuple(pt.to_array() for pt in self.boundary),)
+
     @staticmethod
     def extract_all_from_stl(file_path):
         """Get a list of Face3Ds imported from all of the triangles in an STL file.

tests/face3d_test.py

@@ -112,6 +112,25 @@ def test_face3d_to_from_dict():
     assert new_face.to_dict() == face_dict
 
 
+def test_face3d_to_from_array():
+    """Test the to/from array of Face3D objects."""
+    pts = (Point3D(0, 0, 2), Point3D(0, 2, 2), Point3D(2, 2, 2), Point3D(2, 0, 2))
+    plane = Plane(Vector3D(0, 0, 1), Point3D(0, 0, 2))
+    face = Face3D(pts, plane)
+    face_array = face.to_array()
+    new_face = Face3D.from_array(face_array)
+    assert isinstance(new_face, Face3D)
+    assert new_face.to_array() == face_array
+
+    bound_pts = [Point3D(0, 0), Point3D(4, 0), Point3D(4, 4), Point3D(0, 4)]
+    hole_pts = [Point3D(1, 1), Point3D(3, 1), Point3D(3, 3), Point3D(1, 3)]
+    face = Face3D(bound_pts, None, [hole_pts])
+    face_array = face.to_array()
+    new_face = Face3D.from_array(face_array)
+    assert isinstance(new_face, Face3D)
+    assert new_face.to_array() == face_array
+
+
 def test_face3d_init_from_vertices():
     """Test the initialization of Face3D objects without a plane."""
     pts = (Point3D(0, 0, 2), Point3D(0, 2, 2), Point3D(2, 2, 2), Point3D(2, 0, 2))