Move blit manager update out of mask highlights

This is so that we can better control it and ensure it is only
called once, when needed.

This fixes an issue where the old view would "flash" on the screen
when you switch to any view except raw.

Signed-off-by: Patrick Avery <[email protected]>

Author: psavery

hexrdgui/image_canvas.py

@@ -1559,10 +1559,12 @@ def mask_highlights_changed(self):
             self.clear_mask_highlights()
             for det_name, ax in self.raw_axes.items():
                 self.highlight_masks(ax, det_name)
+            self.blit_manager.update()
             return
 
         if self.mode in (ViewType.polar, ViewType.stereo):
             self.update_mask_highlights(self.axis)
+            self.blit_manager.update()
 
     def polar_masks_changed(self):
         skip = (
@@ -2280,9 +2282,10 @@ def draw_mask_boundaries(self, axis, det=None):
         )
 
     def highlight_masks(self, axis, det=None):
+        # Don't update the blit manager here, so we can better control
+        # it elsewhere
         all_verts = self.get_mask_verts('highlights', det)
         if not all_verts:
-            self.blit_manager.update()
             return
 
         kwargs = {
@@ -2300,8 +2303,6 @@ def highlight_masks(self, axis, det=None):
             axis.add_patch(polygon)
             highlight_artists.append(polygon)
 
-        self.blit_manager.update()
-
     def remove_all_mask_highlight_artists(self):
         self.blit_manager.remove_artists('mask_highlights')
         self.blit_manager.artists['mask_highlights'] = {}