diff --git a/masque/file/gdsii.py b/masque/file/gdsii.py
index 79a8f67..e218545 100644
--- a/masque/file/gdsii.py
+++ b/masque/file/gdsii.py
@@ -13,7 +13,7 @@ import numpy
 from .utils import mangle_name, make_dose_table
 from .. import Pattern, SubPattern, PatternError
 from ..shapes import Polygon
-from ..utils import rotation_matrix_2d, get_bit, vector2
+from ..utils import rotation_matrix_2d, get_bit, set_bit, vector2, is_scalar
 
 
 __author__ = 'Jan Petykiewicz'
@@ -76,15 +76,15 @@ def write(patterns: Pattern or List[Pattern],
             for polygon in shape.to_polygons():
                 xy_open = numpy.round(polygon.vertices + polygon.offset).astype(int)
                 xy_closed = numpy.vstack((xy_open, xy_open[0, :]))
-                if hasattr(polygon.layer, '__len__'):
+                if is_scalar(polygon.layer):
+                    layer = polygon.layer
+                    data_type = 0
+                else:
                     layer = polygon.layer[0]
                     if len(polygon.layer) > 1:
                         data_type = polygon.layer[1]
                     else:
                         data_type = 0
-                else:
-                    layer = polygon.layer
-                    data_type = 0
                 structure.append(gdsii.elements.Boundary(layer=layer,
                                                          data_type=data_type,
                                                          xy=xy_closed))
@@ -184,10 +184,10 @@ def write_dose2dtype(patterns: Pattern or List[Pattern],
                 data_type = dose_vals_list.index(polygon.dose * pat_dose)
                 xy_open = numpy.round(polygon.vertices + polygon.offset).astype(int)
                 xy_closed = numpy.vstack((xy_open, xy_open[0, :]))
-                if hasattr(polygon.layer, '__len__'):
-                    layer = polygon.layer[0]
-                else:
+                if is_scalar(polygon.layer):
                     layer = polygon.layer
+                else:
+                    layer = polygon.layer[0]
                 structure.append(gdsii.elements.Boundary(layer=layer,
                                                          data_type=data_type,
                                                          xy=xy_closed))