As Andrew rightly points out, in M8 this largely meant either transferring a selection from another component to an image or creating a freehand selection in an image and updating the selected pixels in some way. To me, this was one of those magical functions which I have used innumerable times and which stood Manifold 8 out from the pack. It is something that I have long hoped will be added to 9 and perhaps extended to include both freehand selections and updating pixels using other components and selections within these components (either with a selection flag or with values).
By way of examples, I have used the M8 functions (in conjunction with M8’s ‘Selections’ pane tools) to build proposed coastal marine structures into LiDAR DEM’s using architects CAD drawings. This is typically to create the base data for hydrodynamic modelling software to simulate the effects of proposed structures upon currents and the patterns of sediment erosion/deposition.
I also use it to:
- Insert or remove flood control structures in an ‘as built’ state to LiDAR data.
- As part of process to estimate the floodplain extent of rivers from LiDAR.
- Assess river flood inundation in response to flood control structure breaches.
- In preparation for various hydrological modelling similarly to Andrew’s examples.
I have also used it numerous times as a component of creating cartographic presentations.
I should also mention at this point that the ‘Modify Selection' tools in M8 where often invaluable for working with selections once transferred allowing them to be expanded, shrunk or smoothed.
My current pressing need is to allow me to complete a script which produces layers of marine connected and disconnected flood inundation at incremental intervals. This is to support an NZ wide effort to create public facing indicative flood extent viewers in response to sea level rise or other flooding events, similar to the NOAA sea level rise viewer:
I have labored to create a performant script in ArcMap but in parallel have been replicating the process in M9. I have all of the steps in M9 apart from setting the marine disconnected pixels to a value of 99 (green pixels in NOAA’s viewer) for which I need to be able to update pixels under drawing objects.
In ArcMap the un-optimised process on my test data takes ~20 hours to run on my test data set. In contrast, I estimate that with the ability to update my pixels, in M9 the same will take ~10 minutes and would offer the additional benefit of being able to process all data sets at once.
This is something I obviously want to pursue as we will be assisting other authorities around the country with building their own data sets. It also seems perfectly suited to M9’s grid analytics and in addition to saving countless labor hours will allow me to really showcase the utility of M9 to my employers and others.
and what do you want done in the case of conflicts (pixels covered by more than one object)?
Typically I have used this as per the M8 implementation of transferring a selection and then updating the pixels in some way which avoids this problem. In the case that we can update pixels under multiple (potentially overlapping) drawing objects, could the transfer rules not be called into play to determine how to deal with this?
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