Add visual test for scatterregionlayer

glue/viewers/image/tests/test_viewer.py

@@ -4,7 +4,10 @@
 from glue.viewers.image.viewer import SimpleImageViewer
 from glue.core.application_base import Application
 from glue.core.data import Data
+from glue.core.link_helpers import LinkSame
+from glue.core.data_region import RegionData
 
+from shapely.geometry import Polygon, MultiPolygon
 
 @visual_test
 def test_simple_viewer():
@@ -25,3 +28,33 @@ def test_simple_viewer():
     app.data_collection.new_subset_group(label='subset1', subset_state=data1.pixel_component_ids[1] > 1.2)
 
     return viewer.figure
+
+
+@visual_test
+def test_region_layer():
+    poly_1 = Polygon([(20, 20), (60, 20), (60, 40), (20, 40)])
+    poly_2 = Polygon([(60, 50), (60, 70), (80, 70), (80, 50)])
+    poly_3 = Polygon([(10, 10), (15, 10), (15, 15), (10, 15)])
+    poly_4 = Polygon([(10, 20), (15, 20), (15, 30), (10, 30), (12, 25)])
+
+    polygons = MultiPolygon([poly_3, poly_4])
+
+    geoms = np.array([poly_1, poly_2, polygons])
+    values = np.array([1, 2, 3])
+    region_data = RegionData(regions=geoms, values=values)
+
+    image_data = Data(x=np.arange(10000).reshape((100, 100)), label='data1')
+    app = Application()
+    app.data_collection.append(image_data)
+    app.data_collection.append(region_data)
+
+    link1 = LinkSame(region_data.center_x_id, image_data.pixel_component_ids[0])
+    link2 = LinkSame(region_data.center_y_id, image_data.pixel_component_ids[1])
+    app.data_collection.add_link(link1)
+    app.data_collection.add_link(link2)
+
+    viewer = app.new_data_viewer(SimpleImageViewer)
+    viewer.add_data(image_data)
+    viewer.add_data(region_data)
+
+    return viewer.figure