makeValid

Repairs an invalid geometry, returns a repaired, valid geometry. Input geometries are always processed, so even valid inputs may have some minor alterations. The output is always a new geometry object.

Parameters

Name	Type	Default	Description
geometry	Geometry		The geometry to repair
options?	object		Optional parameters to control the algorithm
options.method?	'linework' | 'structure'	'linework'	Method used for fixing invalid geometries. linework - builds valid geometries by first extracting all lines, noding that linework together, then building a value output from the linework structure - is an algorithm that distinguishes between interior and exterior rings, building new geometry by unioning exterior rings, and then differencing all interior rings
options.keepCollapsed?	boolean	false	Only valid for the structure method. When set to false, geometry components that collapse to a lower dimensionality, for example, a one-point linestring would be dropped.

Returns

Geometry

A new repaired geometry

Throws

• GEOSError on unsupported geometry types (curved)

See also

• isValid checks whether a geometry is already valid

Examples

const poly = fromWKT('POLYGON ((2.22 2.28, 7.67 2.06, 10.98 7.7, 9.39 5, 7.96 7.12, 6.77 5.16, 7.43 6.24, 3.7 7.22, 5.72 5.77, 4.18 10.74, 2.2 6.83, 2.22 2.28))');
const valid1 = makeValid(poly);
const valid2 = makeValid(poly, { method: 'structure' });

const poly = fromWKT('POLYGON ((2.22 2.28, 7.67 2.06, 10.98 7.7, 9.39 5, 7.96 7.12, 6.77 5.16, 7.43 6.24, 3.7 7.22, 5.72 5.77, 4.18 10.74, 2.2 6.83, 2.22 2.28))'); const valid1 = makeValid(poly); const valid2 = makeValid(poly, { method: 'structure' });

polygon with hole partially outside shell

const poly = polygon([ [ [ 0, 0 ], [ 0, 2 ], [ 2, 0 ], [ 0, 0 ] ], [ [ 0.5, 0.5 ], [ 2, 1 ], [ 2, 0.5 ], [ 0.5, 0.5 ] ] ]);
const valid1 = makeValid(poly);
const valid2 = makeValid(poly, { method: 'structure' });

const poly = polygon([ [ [ 0, 0 ], [ 0, 2 ], [ 2, 0 ], [ 0, 0 ] ], [ [ 0.5, 0.5 ], [ 2, 1 ], [ 2, 0.5 ], [ 0.5, 0.5 ] ] ]); const valid1 = makeValid(poly); const valid2 = makeValid(poly, { method: 'structure' });

const lineInDisguise = polygon([ [ [ 0, 0 ], [ 1, 1 ], [ 1, 2 ], [ 1, 1 ], [ 0, 0 ] ] ]);
const valid1 = makeValid(lineInDisguise);
// MULTILINESTRING ((0 0, 1 1), (1 1, 1 2))
const valid2 = makeValid(lineInDisguise, { method: 'structure', keepCollapsed: true });
// LINESTRING (0 0, 1 1, 1 2, 1 1, 0 0)
const valid3 = makeValid(lineInDisguise, { method: 'structure' });
// POLYGON EMPTY

const lineInDisguise = polygon([ [ [ 0, 0 ], [ 1, 1 ], [ 1, 2 ], [ 1, 1 ], [ 0, 0 ] ] ]); const valid1 = makeValid(lineInDisguise); // MULTILINESTRING ((0 0, 1 1), (1 1, 1 2)) const valid2 = makeValid(lineInDisguise, { method: 'structure', keepCollapsed: true }); // LINESTRING (0 0, 1 1, 1 2, 1 1, 0 0) const valid3 = makeValid(lineInDisguise, { method: 'structure' }); // POLYGON EMPTY