Hi guys,
it seems to me that there is no way to save the objects marked as
"helper object" when the scene is being saved (it is kinda hard-coded in
the scene writer). While I feel that this is absolutely justified (these
are "helper objects" after all), I would like to have some nodes hidden
from the user, but which would be saved with a project. My use case is:
I have the PlanarFigure data node which represents a segmentation of a
vessel path cross section. It could be a simple circle created manually,
but it can also be a result of smoothing the boundary of a 2D
segmentation. The segmentation is performed on a small (say, 50x50mm)
slice extracted from a reference image and I want to save this slice
along with the segmented slice image to the scene. On the other hand I
don't want to clutter the Data Manager with these nodes. After looking
at the QmitkDataStorageTreeModel and QmitkExtFileSaveProjectAction it
seems to me that this behavior is impossible without modifications to
the MITK code.
What do you think would be a good approach to this problem? For now I
have modified the QmitkDataStorageTreeModel to not show the nodes marked
as ("hidden object" || "helper object"). It works fine except that the
layers are not adjusted for helper objects and I have to set them
manually for the scene to load correctly. Overall, I feel that this is
quite a dirty hack and I would like to hear your opinion on this.
There is still one more problem, however. As the nodes are not visible
in the Data Manager, they cannot be directly deleted when the parent
node is. I can obviously handle this in my view which creates these
objects, but what if the view is closed? It would be nice if I could
mark a node as "Requires hierarchical deletion", which would be
processed by the data storage. What would be the best approach to this?
Perhaps having a data storage listener which would be registered when my
plugin is loaded? Or having my own datastorage subclass which would be
set as the active data storage? Or do you think this might be useful for
a wider range of applications and could be implemented in the
StandaloneDataStorage? Perhaps, a ContourModelSet might be just a node
with metainformation about its hidden children - then the separate
mappers, interactors and IO classes /for the set /wouldn't be necessary
anymore and it might rely on the ContourModel subclasses for that. I
feel that this is a topic for a separate discussion though and I will
write another e-mail about that as it is unclear how to implement some
of the necessary functionalities, but I do believe this is a more
flexible approach.
One unrelated thing is the incremental scene saving. What I mean by that
is while a user works on a project it would be nice to save the progress
from time to time. However, the fact that saving an image takes a very
significant amount of time and that it is being repacked evey time the
scene is saved, I'm afraid that the users will be discouraged to do so.
So it would be nice to speed up the saving process - perhaps by
detecting that the image hasn't changed and it doesn't need to be
repacked or by having the save process in a separate thread. I'm pretty
sure such things already came up and perhaps there is already some
solution to this.
Thank you,
Rostislav.
------------------------------------------------------------------------------
_______________________________________________
mitk-users mailing list
mitk-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/mitk-users
