Merge pull request #27 from Jo-Byr/add-existence-check-to-display-nodes-in-segmentation

enh: add validity checks to display node getters in segmentation

Author: Thibault-Pelletier

tests/test_slice_view.py

@@ -168,6 +168,7 @@ def test_slice_views_can_activate_slab(
     if render_interactive:
         a_slice_view.start_interactor()
 
+
 def test_slice_views_can_set_foregrond_opacity(
     a_slice_view,
     a_background_volume_node,

trame_slicer/segmentation/segmentation.py

@@ -490,14 +490,17 @@ def set_segment_visibility(self, segment_id, visibility: bool) -> None:
             return
 
         display_node = self._segmentation_node.GetDisplayNode()
-        display_node.SetSegmentVisibility(segment_id, visibility)
+        if display_node:
+            display_node.SetSegmentVisibility(segment_id, visibility)
 
     def get_segment_visibility(self, segment_id) -> bool | None:
         if segment_id not in self.get_segment_ids():
             return None
 
         display_node = self._segmentation_node.GetDisplayNode()
-        return display_node.GetSegmentVisibility(segment_id)
+        if display_node:
+            return display_node.GetSegmentVisibility(segment_id)
+        return None
 
     def set_opacity_mode(self, opacity_mode: SegmentationOpacityEnum) -> None:
         if not self._segmentation_node:
@@ -510,6 +513,8 @@ def get_opacity_mode(self) -> SegmentationOpacityEnum | None:
         if not self._segmentation_node:
             return None
         display_node = self._segmentation_node.GetDisplayNode()
+        if display_node is None:
+            return None
         fill_visibility = display_node.GetVisibility2DFill()
         outline_visibility = display_node.GetVisibility2DOutline()
         if outline_visibility and not fill_visibility:
@@ -522,23 +527,29 @@ def get_2d_opacity(self) -> float | None:
         if not self._segmentation_node:
             return None
         display_node = self._segmentation_node.GetDisplayNode()
-        return display_node.GetOpacity2DFill()
+        if display_node:
+            return display_node.GetOpacity2DFill()
+        return None
 
     def set_2d_opacity(self, opacity: float) -> None:
         if not self._segmentation_node:
             return
         display_node = self._segmentation_node.GetDisplayNode()
-        display_node.SetOpacity2DFill(opacity)
-        display_node.SetOpacity2DOutline(opacity)
+        if display_node:
+            display_node.SetOpacity2DFill(opacity)
+            display_node.SetOpacity2DOutline(opacity)
 
     def get_3d_opacity(self) -> float | None:
         if not self._segmentation_node:
             return None
         display_node = self._segmentation_node.GetDisplayNode()
-        return display_node.GetOpacity3D()
+        if display_node:
+            return display_node.GetOpacity3D()
+        return None
 
     def set_3d_opacity(self, opacity: float) -> None:
         if not self._segmentation_node:
             return
         display_node = self._segmentation_node.GetDisplayNode()
-        display_node.SetOpacity3D(opacity)
+        if display_node:
+            display_node.SetOpacity3D(opacity)