fix: Fix rendering of alternative representation if there are more components in the alternative representation than in ROI

.github/project_dict.pws

@@ -1,4 +1,4 @@
-personal_ws-1.1 en 14
+personal_ws-1.1 en 15
 napari
 autoupdate
 aspell
@@ -13,3 +13,4 @@ bool
 changelog
 czi
 PartSeg
+ROI

package/PartSeg/common_gui/napari_image_view.py

@@ -483,8 +483,10 @@ def get_roi_view_parameters(self, image_info: ImageInfo) -> ColorInfo:
             or colors.size == 0
         ):
             return {0: [0, 0, 0, 0], None: [0, 0, 0, 0]}
-
-        res = {x: colors[(x - 1) % colors.shape[0]] for x in range(1, image_info.roi_count + 1)}
+        res = {
+            x: colors[(x - 1) % colors.shape[0]]
+            for x in range(1, image_info.roi_info.get_components_num(self.roi_alternative_selection) + 1)
+        }
         res[0] = [0, 0, 0, 0]
         res[None] = [0, 0, 0, 0]
         return res

package/PartSegCore/roi_info.py

@@ -62,6 +62,7 @@ def __init__(
         self.roi = roi
         self.bound_info = self.calc_bounds(roi)
         self.sizes = np.bincount(roi.flat)
+        self._alternative_component_size = {}
 
     def fit_to_image(self, image: Image) -> "ROIInfo":
         if self.roi is None:
@@ -70,6 +71,23 @@ def fit_to_image(self, image: Image) -> "ROIInfo":
         alternatives = {k: image.fit_array_to_image(v) for k, v in self.alternative.items()}
         return ROIInfo(roi, self.annotations, alternatives)
 
+    def get_components_num(self, name):
+        """
+        Get the number of components for a given representation.
+
+        Args:
+            name (str): Name of the representation. Use "ROI" for the main ROI,
+                       or the name of an alternative representation.
+
+        Returns:
+            int: Maximum component number in the specified representation.
+        """
+        if name == "ROI" or name not in self.alternative:
+            return max(self.bound_info)
+        if name not in self._alternative_component_size:
+            self._alternative_component_size[name] = np.max(self.alternative[name])
+        return self._alternative_component_size[name]
+
     def __str__(self):
         return f"ROIInfo; components: {len(self.bound_info)}, sizes: {self.sizes}"
 

package/tests/test_PartSegCore/test_segmentation.py

@@ -761,7 +761,7 @@ def test__convex_fill(self):
         assert _convex_fill(arr) is None
 
 
-class TestSegmentationInfo:
+class TestROIInfo:
     def test_none(self):
         si = ROIInfo(None)
         assert si.roi is None
@@ -817,6 +817,21 @@ def test_multiple_components(self, comp_num):
         assert np.all(si.bound_info[1].lower == 2)
         assert np.all(si.bound_info[1].upper == [10 * comp_num - 1, 8])
 
+    def test_alternative(self):
+        data = np.zeros((10, 10), dtype=np.uint8)
+        data[2:8, 2:4] = 1
+        data[2:8, 4:8] = 2
+        alt1 = np.copy(data)
+        alt1[data == 1] = 4
+        alt1[data == 2] = 1
+        alt2 = np.zeros((10, 10), dtype=np.uint8)
+
+        ri = ROIInfo(data, alternative={"alt1": alt1, "alt2": alt2})
+        assert ri.get_components_num("ROI") == 2
+        assert ri.get_components_num("alt1") == 4
+        assert ri.get_components_num("alt2") == 0
+        assert ri.get_components_num("alt3") == 2
+
 
 def test_bound_info():
     bi = BoundInfo(lower=np.array([1, 1, 1]), upper=np.array([5, 6, 7]))