refactor(render): thread color_spec through _render_points mutation pipeline (#700)

Author: timtreis

src/spatialdata_plot/pl/render.py

@@ -1465,7 +1465,6 @@ def _render_points(
         preloaded_color_data=_preloaded,
     )
     colortype = color_spec.colortype
-    color_source_vector, color_vector = color_spec.source_vector, color_spec.color_vector
 
     if added_color_from_table and col_for_color is not None:
         _reparse_points(
@@ -1477,15 +1476,18 @@ def _render_points(
             col_for_color,
         )
 
-    _warn_groups(groups, colortype, color_source_vector, col_for_color)
+    _warn_groups(groups, colortype, color_spec.source_vector, col_for_color)
 
     # When groups are specified, filter out non-matching elements by default.
     # Only show non-matching elements if the user explicitly sets na_color.
     _na = render_params.cmap_params.na_color
-    if groups is not None and color_source_vector is not None and (_na.default_color_set or _na.is_fully_transparent()):
-        keep, color_source_vector, color_vector = _filter_groups_transparent_na(
-            groups, color_source_vector, color_vector
-        )
+    if (
+        groups is not None
+        and color_spec.source_vector is not None
+        and (_na.default_color_set or _na.is_fully_transparent())
+    ):
+        keep = color_spec.source_vector.isin(groups)
+        color_spec = color_spec.filter(keep)
         n_points = int(keep.sum())
         if n_points == 0:
             return
@@ -1494,7 +1496,9 @@ def _render_points(
         adata = adata[keep]
         _reparse_points(sdata_filt, element, points, transformation_in_cs, coordinate_system, col_for_color)
 
-    color_vector = _maybe_apply_transfunc(colortype, color_vector, render_params.transfunc)
+    # carrier pipeline done; unpack the final vectors for the read/draw phase below
+    color_spec = color_spec.apply_transfunc(render_params.transfunc)
+    color_source_vector, color_vector = color_spec.source_vector, color_spec.color_vector
 
     trans, trans_data = _prepare_transformation(sdata.points[element], coordinate_system, ax)