Add test case

Author: aeisenbarth

tests/_images/Labels_can_render_transformed_labels_with_outline.png

@@ -10,6 +10,7 @@
 from spatialdata import SpatialData
 from spatialdata._core.query.relational_query import _get_unique_label_values_as_index
 from spatialdata.models import TableModel
+from spatialdata.transformations import Affine, Scale, Sequence, Translation, set_transformation
 
 from tests.conftest import DPI, PlotTester, PlotTesterMeta
 
@@ -111,6 +112,34 @@ def test_can_plot_with_one_element_color_table(self, sdata_blobs: SpatialData):
     def test_plot_label_categorical_color(self, sdata_blobs: SpatialData, label: str):
         self._make_tablemodel_with_categorical_labels(sdata_blobs, label)
 
+    def test_plot_can_render_transformed_labels_with_outline(self, sdata_blobs: SpatialData):
+        # Blobs have by default an identity transform. Replace it by a rotated, scaled transform:
+        angle = np.deg2rad(15)
+        axes = ("y", "x")
+        rotation = Affine(
+            matrix=np.array(
+                [
+                    [np.cos(angle), -np.sin(angle), 0],
+                    [np.sin(angle), np.cos(angle), 0],
+                    [0, 0, 1],
+                ]
+            ),
+            input_axes=axes,
+            output_axes=axes,
+        )
+        translation = Translation([10, 10], axes=axes)
+        scale = Scale([0.65, 0.65], axes=axes)
+        transform = Sequence([translation, rotation, scale])
+        set_transformation(sdata_blobs["blobs_labels"], transform)
+
+        # Render without fill, but with outline.
+        sdata_blobs.pl.render_labels(
+            "blobs_labels",
+            fill_alpha=0.0,
+            outline=True,
+            outline_alpha=1.0,
+        ).pl.show()
+
     def _make_tablemodel_with_categorical_labels(self, sdata_blobs, label):
         n_obs = max(_get_unique_label_values_as_index(sdata_blobs[label]))
         adata = AnnData(