read EAM native spectral-element grids, and make formats pluggable

src/e3sm_quickview/app.py

@@ -493,6 +493,11 @@ async def data_loading_open(self, simulation, connectivity):
             conn_file=connectivity,
         )
 
+        # A different format means a different pipeline; existing views are
+        # still wired to the old one.
+        if self.source.path_changed:
+            self.view_manager.drop_views()
+
         self.file_browser.loading_completed(self.source.valid)
 
         if self.source.valid:
@@ -687,9 +692,30 @@ def _on_slicing_change(self, var, ind_var, **_):
                 geom_filter.Update()
                 data = geom_filter.GetOutput()
                 self.state.fields_avgs = compute.extract_avgs(
-                    data, self.selected_variable_names
+                    data, self.selected_variable_names, self.source.association
                 )
 
+    @change("longitude_origin")
+    def _on_longitude_origin(self, longitude_origin, **_):
+        """Rotate the map so its left edge sits at the chosen longitude."""
+        if not self.source.valid:
+            return
+
+        origin = float(longitude_origin)
+        with perf.timed("longitude_origin.total"):
+            self.source.SetLongitudeOrigin(origin)
+            # The crop is expressed in the map's own longitudes, so rotating the
+            # map invalidates the previous selection -- a stale one would sit
+            # partly outside the window, or straddle its seam, which the box
+            # crop used for the continents and the graticule cannot represent.
+            with self.state as s:
+                s.crop_longitude = [origin, origin + 360]
+                s.crop_longitude_min = origin
+                s.crop_longitude_max = origin + 360
+            self.view_manager.update_color_range()
+            self.view_manager.reset_camera()
+            self.view_manager.render()
+
     @change(
         "variables_loaded",
         "crop_longitude",
@@ -725,7 +751,7 @@ def _on_downstream_change(
                 geom_filter.Update()
                 data = geom_filter.GetOutput()
                 self.state.fields_avgs = compute.extract_avgs(
-                    data, self.selected_variable_names
+                    data, self.selected_variable_names, self.source.association
                 )
 
     def toggle_toolbar(self, toolbar_name=None):

src/e3sm_quickview/components/toolbars.py

@@ -324,8 +324,8 @@ def __init__(self):
                         )
                     v3.VRangeSlider(
                         v_model=("crop_longitude", [-180, 180]),
-                        min=-180,
-                        max=180,
+                        min=("longitude_origin",),
+                        max=("longitude_origin + 360",),
                         step=1,
                         density="compact",
                         hide_details=True,
@@ -407,11 +407,31 @@ def __init__(self):
                         density="compact",
                         hide_details=True,
                     )
+
+                with v3.VCol():
+                    with v3.VRow(classes="mx-2 my-0"):
+                        v3.VLabel(
+                            "Map origin",
+                            classes="text-subtitle-2",
+                        )
+                        v3.VSpacer()
+                        v3.VLabel(
+                            "{{ longitude_origin }} to {{ longitude_origin + 360 }}",
+                            classes="text-body-2",
+                        )
+                    v3.VSlider(
+                        v_model=("longitude_origin", -180),
+                        min=-180,
+                        max=180,
+                        step=1,
+                        density="compact",
+                        hide_details=True,
+                    )
             with v3.VRow(classes="ma-0 pl-6 pr-2 align-center ga-4", v_else=True):
                 v3.VNumberInput(
                     label="Longitude (min)",
                     v_model=("crop_longitude_min", -180),
-                    min=[-180],
+                    min=("longitude_origin",),
                     max=("crop_longitude_max", 180),
                     step=[1],
                     hide_details=True,
@@ -424,7 +444,7 @@ def __init__(self):
                     label="Longitude (max)",
                     v_model=("crop_longitude_max", 180),
                     min=("crop_longitude_min", -180),
-                    max=[180],
+                    max=("longitude_origin + 360",),
                     step=[1],
                     hide_details=True,
                     density="comfortable",