mapbox / mapbox/tippecanoe

Problems generating a tileset for a large dataset which mix large and small polygons

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Dominant language
C++
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Description

I have large polygon dataset which mix small polygon with very large polygons. When trying to display all in the view at z13 the tiny polygons looks like this:
![image](https://user-images.githubusercontent.com/83005561/175518683-4a9ee1c2-ab7a-4987-812c-5450edd9a4cf.png)
I have tried to drop polygons but then there are many blank spaces or if coalesce it lost data at that zoom level.

By the other side i have this issue when trying to avoid clipping the big features which is the big problem: so when using -pc in the Tippecanoe I receive the errors of (Large unclipped (-pc) feature may be duplicated across 139629 tiles Exiting because this can't be right.) and when avoid using the -pc flag I have the tiles like this:

![image](https://user-images.githubusercontent.com/83005561/175521820-53c32f8f-912f-4fdc-bb8d-0b0cd8160e5d.png)

I have tried several commands but don't find the correct configuration and cannot find

Contributor guide

Open the contributing guide

Research direction

Start by reproducing the large mixed-polygon dataset at zoom 13 with and without the -pc flag, then compare the effects of dropping and coalescing polygons. The issue is complete when the large features avoid unacceptable clipping or duplication while the small polygons remain represented without blank spaces.

Written by the indexing model from the issue text.

Assessment

Tech stack
cpp
Domain
data
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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