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cldellow / tilemaker

Make OpenStreetMap vector tiles without the stack
https://tilemaker.org/
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simplification introduces errors for Jasper NP #10

Open cldellow opened 1 month ago

cldellow commented 1 month ago

With simplification:

simplify_below: 12,
simplify_level: 0.00002,

There is an artifact at 6/11/21: http://localhost:8081/map#6.91/52.281/-117.778

Selection_796

If you disable simplification, it looks good: Selection_797

Even with simplification, the artifact is not present at 7/22/42:

Selection_799

cldellow commented 1 month ago

Disabling the clipping that happens in buildWayGeometry also resolves the issue. Change: https://github.com/systemed/tilemaker/blob/e42aaa751608689586d091e7b377141e2211267d/src/tile_data.cpp#L272-L279

To be:

populateMultiPolygon(uncached, objectID);
return uncached;

This will cause a large performance regression, though, so is probably to be avoided.

I wonder if bumping up the margin a lot would avoid the issue and let us still be fast?

cldellow commented 1 month ago

Increasing the margin just moves the error around -- z6/11/21 renders fine, but z7/22/42 doesn't.

Interestingly, eliminating the margin seemed to work. The margin was introduced in the very first commit: https://github.com/systemed/tilemaker/blame/30957369ec8a06a61888b3f8cff104c263afd8f4/src/coordinates.cpp

...maybe it's not needed?

There's also an issue with water:

Selection_798

Going to see if that goes away with this, too.