overlaps

Returns true if geometries a and b spatially overlap.

Geometry a overlaps geometry b if both geometries have some, but not all points in common, they have the same dimension and the intersection of their interiors has the same dimension as the geometries themselves.

warning

Do not use this function with invalid geometries. You will get unexpected results.

Parameters

Name	Type	Description
a	Geometry | Prepared<Geometry>	First geometry
b	Geometry	Second geometry

Returns

boolean

true if geometry a overlaps geometry b

Throws

• GEOSError on unsupported geometry types (curved)

See also

• prepare improves performance of repeated calls against a single geometry

Examples

overlaps: true

const a = multiPoint([ [ 2, 6 ], [ 3, 4 ], [ 6, 4 ], [ 1, 0 ] ]);
const b = multiPoint([ [ 0, 3 ], [ 3, 4 ], [ 4, 2 ], [ 5, 5 ] ]);
const ab_overlap = overlaps(a, b); // true

const c = lineString([ [ 10, 5 ], [ 15, 0 ] ]);
const d = lineString([ [ 10, 2 ], [ 12, 3 ], [ 13, 2 ], [ 15, 3 ] ]);
const cd_overlap = overlaps(c, d); // true

const e = polygon([ [ [ 18, 0 ], [ 18, 7 ], [ 22, 7 ], [ 22, 0 ], [ 18, 0 ] ] ]);
const f = polygon([ [ [ 20, 1 ], [ 20, 4 ], [ 26, 4 ], [ 26, 1 ], [ 20, 1 ] ] ]);
const ef_overlap = overlaps(e, f); // true

const a = multiPoint([ [ 2, 6 ], [ 3, 4 ], [ 6, 4 ], [ 1, 0 ] ]); const b = multiPoint([ [ 0, 3 ], [ 3, 4 ], [ 4, 2 ], [ 5, 5 ] ]); const ab_overlap = overlaps(a, b); // true const c = lineString([ [ 10, 5 ], [ 15, 0 ] ]); const d = lineString([ [ 10, 2 ], [ 12, 3 ], [ 13, 2 ], [ 15, 3 ] ]); const cd_overlap = overlaps(c, d); // true const e = polygon([ [ [ 18, 0 ], [ 18, 7 ], [ 22, 7 ], [ 22, 0 ], [ 18, 0 ] ] ]); const f = polygon([ [ [ 20, 1 ], [ 20, 4 ], [ 26, 4 ], [ 26, 1 ], [ 20, 1 ] ] ]); const ef_overlap = overlaps(e, f); // true

overlaps: false

const a = multiPoint([ [ 2, 6 ], [ 3, 4 ], [ 6, 4 ], [ 1, 0 ] ]);
const b = multiPoint([ [ 1, 0 ], [ 3, 4 ] ]);
const ab_overlap = overlaps(a, b); // false - all points from `b` are within `a`

const c = lineString([ [ 13, 5 ], [ 12, 0 ] ]);
const d = lineString([ [ 10, 2 ], [ 12, 3 ], [ 13, 2 ], [ 15, 3 ] ]);
const cd_overlap = overlaps(c, d); // false - intersection has lower dimension (point instead of line)

const e = polygon([ [ [ 18, 0 ], [ 18, 7 ], [ 22, 7 ], [ 22, 0 ], [ 18, 0 ] ] ]);
const f = polygon([ [ [ 22, 1 ], [ 22, 4 ], [ 26, 4 ], [ 26, 1 ], [ 22, 1 ] ] ]);
const ef_overlap = overlaps(e, f); // false - intersection has lower dimension (line instead of polygon)

const g = polygon([ [ [ 30, 0 ], [ 30, 5 ], [ 35, 5 ], [ 35, 0 ], [ 30, 0 ] ] ]);
const h = lineString([ [ 29, 2 ], [ 36, 3 ] ]);
const gh_overlap = overlaps(g, h); // false - different dimensions cannot overlap

const a = multiPoint([ [ 2, 6 ], [ 3, 4 ], [ 6, 4 ], [ 1, 0 ] ]); const b = multiPoint([ [ 1, 0 ], [ 3, 4 ] ]); const ab_overlap = overlaps(a, b); // false - all points from `b` are within `a` const c = lineString([ [ 13, 5 ], [ 12, 0 ] ]); const d = lineString([ [ 10, 2 ], [ 12, 3 ], [ 13, 2 ], [ 15, 3 ] ]); const cd_overlap = overlaps(c, d); // false - intersection has lower dimension (point instead of line) const e = polygon([ [ [ 18, 0 ], [ 18, 7 ], [ 22, 7 ], [ 22, 0 ], [ 18, 0 ] ] ]); const f = polygon([ [ [ 22, 1 ], [ 22, 4 ], [ 26, 4 ], [ 26, 1 ], [ 22, 1 ] ] ]); const ef_overlap = overlaps(e, f); // false - intersection has lower dimension (line instead of polygon) const g = polygon([ [ [ 30, 0 ], [ 30, 5 ], [ 35, 5 ], [ 35, 0 ], [ 30, 0 ] ] ]); const h = lineString([ [ 29, 2 ], [ 36, 3 ] ]); const gh_overlap = overlaps(g, h); // false - different dimensions cannot overlap