Simplify
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Simplification method

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Simplified lines remain within a given distance of original lines. Good for thinning dense points but tends to form spikes at high simplification.
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Lines are simplified by iteratively removing the point that forms the least-area triangle with two adjacent points.
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Points located at the vertex of more acute angles are preferentially removed. Recommended for mapping.

Other options

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Remove line intersections. Works by rolling back simplification along intersecting segments.
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Automatically fix minor topology errors by snapping together points that are almost identical. Doesn't apply to TopoJSON files.
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Prevent small polygons from disappearing at high simplification. Protects the largest ring of multi- ring features.
coordinate precision
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Round coordinates by a specified precision. Reduces the size of GeoJSON files but can cause intersections and collapsed shapes. Uses same units as the source file, e.g. decimal degrees for most unprojected files.
0 line intersections
Repair