Backport PR spacetelescope#3215: imviz matched zoom: use center & rad…

…ius instead of corners (spacetelescope#3226)

Co-authored-by: Kyle Conroy <kyleconroy@gmail.com>

CHANGES.rst

@@ -4,6 +4,8 @@ A.B.1 (unreleased)
 Bug Fixes
 ---------
 
+- Improved performance and removed jittering for the matched box zoom tool. [#3215]
+
 Cubeviz
 ^^^^^^^
 

jdaviz/configs/cubeviz/plugins/tests/test_tools.py

@@ -150,7 +150,9 @@ def test_spectrum_at_spaxel_altkey_true(cubeviz_helper, spectrum1d_cube,
         flux_viewer.state.x_max = 40
         flux_viewer.state.y_max = 35
     v = uncert_viewer
-    assert (v.state.x_min, v.state.x_max, v.state.y_min, v.state.y_max) == (20, 40, 15, 35)
+    assert v.state.zoom_center_x == flux_viewer.state.zoom_center_x
+    assert v.state.zoom_center_y == flux_viewer.state.zoom_center_y
+    assert v.state.zoom_radius == flux_viewer.state.zoom_radius
     t_linkedpan.deactivate()
 
 

jdaviz/configs/cubeviz/plugins/tools.py

@@ -17,8 +17,12 @@
 
 
 class _PixelMatchedZoomMixin(_MatchedZoomMixin):
-    match_keys = ('x_min', 'x_max', 'y_min', 'y_max')
-    disable_matched_zoom_in_other_viewer = False
+    match_axes = []
+    disable_matched_zoom_in_other_viewer = True
+
+    @property
+    def match_keys(self):
+        return ['zoom_center_x', 'zoom_center_y', 'zoom_radius']
 
     def _is_matched_viewer(self, viewer):
         return isinstance(viewer, BqplotImageView)

jdaviz/configs/imviz/plugins/tools.py

@@ -16,9 +16,13 @@
 
 
 class _ImvizMatchedZoomMixin(_MatchedZoomMixin):
-    match_keys = ('x_min', 'x_max', 'y_min', 'y_max')
+    match_axes = []
     disable_matched_zoom_in_other_viewer = True
 
+    @property
+    def match_keys(self):
+        return ['zoom_center_x', 'zoom_center_y', 'zoom_radius']
+
     def _is_matched_viewer(self, viewer):
         return isinstance(viewer, BqplotImageView)
 

jdaviz/configs/imviz/tests/test_tools.py

@@ -15,19 +15,25 @@ def test_panzoom_tools(self):
 
         t = v.toolbar.tools['jdaviz:boxzoommatch']
         # original limits (x_min, x_max, y_min, y_max): -0.5 9.5 -0.5 9.5
+        # original limits (zoom_center_x, zoom_center_y, zoom_radius): 4.5 4.5 5.0
         original_limits = (v.state.x_min, v.state.x_max, v.state.y_min, v.state.y_max)
         assert_allclose(original_limits, (-0.5, 9.5, -0.5, 9.5))
+        original_center_rad = (v.state.zoom_center_x, v.state.zoom_center_y, v.state.zoom_radius)
+        assert_allclose(original_center_rad, (4.5, 4.5, 5.0))
         assert_allclose((v2.state.x_min, v2.state.x_max, v2.state.y_min, v2.state.y_max), original_limits)  # noqa
+        assert_allclose((v2.state.zoom_center_x, v2.state.zoom_center_y, v2.state.zoom_radius), original_center_rad)  # noqa
         t.activate()
         t.save_prev_zoom()
         v.state.x_min, v.state.x_max, v.state.y_min, v.state.y_max = (1, 8, 1, 8)
-        # second viewer should match these changes
-        assert (v2.state.x_min, v2.state.x_max, v2.state.y_min, v2.state.y_max) == (1, 8, 1, 8)
+        # second viewer should match these changes, wrt zoom center and radius
+        assert v2.state.zoom_center_x == v.state.zoom_center_x
+        assert v2.state.zoom_center_y == v.state.zoom_center_y
+        assert v2.state.zoom_radius == v.state.zoom_radius
 
         v.toolbar.tools['jdaviz:prevzoom'].activate()
-        # both should revert since they're still linked
-        assert_allclose((v.state.x_min, v.state.x_max, v.state.y_min, v.state.y_max), original_limits)  # noqa
-        assert_allclose((v2.state.x_min, v2.state.x_max, v2.state.y_min, v2.state.y_max), original_limits)  # noqa
+        # both should revert since they're still linked (boxzoommatch will re-activate)
+        assert_allclose((v.state.zoom_center_x, v.state.zoom_center_y, v.state.zoom_radius), original_center_rad)  # noqa
+        assert_allclose((v2.state.zoom_center_x, v2.state.zoom_center_y, v2.state.zoom_radius), original_center_rad)  # noqa
 
         v.toolbar.tools['jdaviz:prevzoom'].activate()
         # both should revert since they're still linked

jdaviz/core/tools.py

@@ -3,6 +3,7 @@
 
 import numpy as np
 from echo import delay_callback
+from functools import cached_property
 from glue.config import viewer_tool
 from glue.core import HubListener
 from glue.viewers.common.tool import Tool
@@ -67,6 +68,14 @@ def match_keys(self):
             keys += [f'{ax}_min', f'{ax}_max']
         return keys
 
+    @cached_property
+    def delay_callback_keys(self):
+        all_keys = ['x_min', 'x_max', 'y_min', 'y_max',
+                    'zoom_center_x', 'zoom_center_y', 'zoom_radius']
+        return [k for k in all_keys
+                if np.all([hasattr(v.state, k)
+                           for v in self._iter_matched_viewers(include_self=True)])]
+
     def activate(self):
         if self.disable_matched_zoom_in_other_viewer:
             # mapping limits are not guaranteed to roundtrip, so we need to disable
@@ -115,8 +124,8 @@ def on_limits_change(self, *args):
                 viewer.zoom_level = old_level * float(to_fov_sky / orig_fov_sky)
                 viewer.center_on(sky_cen)
 
-            else:
-                with delay_callback(viewer.state, *self.match_keys):
+            elif len(self.match_axes):
+                with delay_callback(viewer.state, *self.delay_callback_keys):
                     for ax in self.match_axes:
                         if None in orig_lims.values():
                             orig_range = np.inf
@@ -134,6 +143,13 @@ def on_limits_change(self, *args):
                             if not np.isnan(value) and (orig_value is None or
                                                         abs(value-orig_lims.get(k, np.inf)) > tol):
                                 setattr(viewer.state, k, value)
+            else:
+                # match keys, but not match axes (e.g., zoom_center and zoom_radius)
+                with delay_callback(viewer.state, *self.delay_callback_keys):
+                    for k in self.match_keys:
+                        value = to_lims.get(k)
+                        if not np.isnan(value):
+                            setattr(viewer.state, k, value)
 
     def is_visible(self):
         return len(self.viewer.jdaviz_app._viewer_store) > 1