From cbfda384f47ad85ce8725a4e7f77e0135ecc3f3e Mon Sep 17 00:00:00 2001
From: Paul McCarthy <pauld.mccarthy@gmail.com>
Date: Mon, 20 Jul 2015 22:11:31 +0100
Subject: [PATCH] Bugfix to DisplayContext overlayOrder update - should have
noticed this a long time ago. Overlay order was not being preserved when
overlays were removed from the list.
---
fsl/fslview/displaycontext/displaycontext.py | 51 +++++++++++++++++---
1 file changed, 43 insertions(+), 8 deletions(-)
diff --git a/fsl/fslview/displaycontext/displaycontext.py b/fsl/fslview/displaycontext/displaycontext.py
index 623c0286e..1804040ea 100644
--- a/fsl/fslview/displaycontext/displaycontext.py
+++ b/fsl/fslview/displaycontext/displaycontext.py
@@ -290,21 +290,56 @@ class DisplayContext(props.SyncableHasProperties):
# Ensure that the overlayOrder
# property is valid ...
+ #
+ # NOTE: The following logic assumes that operations
+ # which modify the overlay list will only do
+ # one of the following:
+ #
+ # - Adding one or more overlays to the list
+ # - Removing one or more overlays from the list
#
+ # More complex overlay list modifications
+ # will cause this code to break.
+
+ oldList = self.__overlayList.getLastValue('overlays')[:]
+ oldOrder = self.overlayOrder[:]
+
# If overlays have been added to
# the overlay list, add indices
# for them to the overlayOrder list
if len(self.overlayOrder) < len(self.__overlayList):
- self.overlayOrder.extend(range(len(self.overlayOrder),
- len(self.__overlayList)))
- # Otherwise, if overlays have been removed
- # from the overlay list, remove the corresponding
- # indices from the overlayOrder list
+ newOrder = []
+ newOverlayIdx = len(oldList)
+
+ # The order of existing overlays is preserved,
+ # and all new overlays added to the end of the
+ # overlay order.
+ for overlay in self.__overlayList:
+
+ if overlay in oldList:
+ newOrder.append(oldOrder[oldList.index(overlay)])
+ else:
+ newOrder.append(newOverlayIdx)
+ newOverlayIdx += 1
+
+ self.overlayOrder[:] = newOrder
+
+ # Otherwise, if overlays have been
+ # removed from the overlay list ...
elif len(self.overlayOrder) > len(self.__overlayList):
- for idx in range(len(self.__overlayList),
- len(self.overlayOrder)):
- self.overlayOrder.remove(idx)
+
+ # Remove the corresponding indices
+ # from the overlayOrder list
+ for overlay, orderIdx in zip(oldList, self.overlayOrder):
+ if overlay not in self.__overlayList:
+ oldOrder.remove(orderIdx)
+
+ # Re-generate new indices,
+ # preserving the order of
+ # the remaining overlays
+ newOrder = [sorted(oldOrder).index(idx) for idx in oldOrder]
+ self.overlayOrder[:] = newOrder
# Ensure that the bounds property is accurate
self.__updateBounds()
--
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