+5FME Desktop 2022: How to identify gaps between the polygons of same layer?
In the screenshot below, I have a layer that has 6 polygons. It’s easy to identify the overlaps between these polygons with the “AreaOnArea” tool but how gaps can be identified?
Best answer by geomancer
Use a Dissolver instead of an Aggregator.
Take the results of the Outershell port of the DonutHoleExtractor, buffer by your favorite tolerance, perform an AreaOnAreaOverlayer, keep only the features with _overlaps >= 2, clip with the results of the Outershell port of the DonutHoleExtractor, and keep only the results of the Outside port.
+51+5
1) The “AreaOnAreaOverlayer” tool doesn’t catch the gaps
2) The “AreaGapAndOverlapCleaner” tool doesn’t identify the gaps\\overlap but rather resolve
Is there a tool that can identify the gaps\\overlaps?
+63If you're looking for gaps, use the AreaGapAndOverlapCleaner, then use the repaired output as clippees and your original geom as the clipper. The Outside port will have the gap geometries
+5Thank you for the help.
My issue here is to identify the gaps and overlaps BUT not to resolve them
Of course, overlaps can be easily identified, but i couldn't figure out who to do so for gaps.
is this still be possible?
Sample data and workbench are attached
+5I used the "aggregator" tool (based on the autocad_hatch field) then the "DonutHoleExtractor" but fails to identify the gaps
+13Hi @jamal ,
Not sure if you solved this question. I've tried some sort of solution, and here is my output:
In total there are up to 20 gaps between your 6 geometries.
Here is the workflow:
Let me know if you have any doubts,
Keep talking,
Juanma,
+58I used the "aggregator" tool (based on the autocad_hatch field) then the "DonutHoleExtractor" but fails to identify the gaps
Use a Dissolver instead of an Aggregator.
+5Use a Dissolver instead of an Aggregator.
That's great. However, in my case, gaps need to be indentified between all polygons considering a certain tolerance (say 55 meter).
Then how to catch the indicate gab below as the tolerance is less than 55 meter
The data is attached
+58Use a Dissolver instead of an Aggregator.
Take the results of the Outershell port of the DonutHoleExtractor, buffer by your favorite tolerance, perform an AreaOnAreaOverlayer, keep only the features with _overlaps >= 2, clip with the results of the Outershell port of the DonutHoleExtractor, and keep only the results of the Outside port.
+63Thank you for the help.
My issue here is to identify the gaps and overlaps BUT not to resolve them
Of course, overlaps can be easily identified, but i couldn't figure out who to do so for gaps.
is this still be possible?
Sample data and workbench are attached
The solution I posted outputs the gaps on the Outside port on the Clipper
+5Thank you very much geomancer for the help. It works perfectly
My thanks are extended to Juanma for the other approach provided
+5I applied it on the k22.dwg and it works fine
+5The solution I posted outputs the gaps on the Outside port on the Clipper
Many thanks hkingsbury for the useful input
