6257ddba78
The big change is that the GeoJSON package has been completely rewritten to fix a few of geometry calculation bugs, increase performance, and to better follow the GeoJSON spec RFC 7946. GeoJSON updates - A LineString now requires at least two points. - All json members, even foreign, now persist with the object. - The bbox member persists too but is no longer used for geometry calculations. This is change in behavior. Previously Tile38 would treat the bbox as the object's physical rectangle. - Corrections to geometry intersects and within calculations. Faster spatial queries - The performance of Point-in-polygon and object intersect operations are greatly improved for complex polygons and line strings. It went from O(n) to roughly O(log n). - The same for all collection types with many children, including FeatureCollection, GeometryCollection, MultiPoint, MultiLineString, and MultiPolygon. Codebase changes - The pkg directory has been renamed to internal - The GeoJSON internal package has been moved to a seperate repo at https://github.com/tidwall/geojson. It's now vendored. Please look out for higher memory usage for datasets using complex shapes. A complex shape is one that has 64 or more points. For these shapes it's expected that there will be increase of least 54 bytes per point.
18 lines
440 B
Go
18 lines
440 B
Go
package clip
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import (
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"github.com/tidwall/geojson"
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"github.com/tidwall/geojson/geometry"
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)
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func clipRect(rect *geojson.Rect, clipper geojson.Object) geojson.Object {
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base := rect.Base()
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points := make([]geometry.Point, base.NumPoints())
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for i := 0; i < len(points); i++ {
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points[i] = base.PointAt(i)
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}
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poly := geometry.NewPoly(points, nil, geometry.DefaultIndex)
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gPoly := geojson.NewPolygon(poly)
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return Clip(gPoly, clipper)
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}
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