High-resolution geometries at max zoom level #384
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This introduces a new
high_resolutionparameter in the global layer config.When set, this uses an extent/resolution of 8192 at the maximum zoom (typically 14), rather than the usual 4096. The effect of this is that geometries continue to look correct when zoomed in up to (say) z18, rather than taking on a wonky appearance from rounding artefacts.
For a building-heavy city extract this results in an .mbtiles filesize increase of around 4%.
Buildings viewed at z18 without this parameter set (look at the nominally straight edges of the terraced buildings):
With it set:
(I did experiment with using
roundrather thanfloorat higher zoom levels but, slightly to my surprise, it doesn't appear to make things any better.)