intersection

Computes the intersection of geometry a with geometry b. The result is a geometry that contains all points that are both in geometry a and geometry b.

Parameters

Name	Type	Description
a	Geometry	First geometry
b	Geometry	Second geometry
options?	object	Optional options object
options.gridSize?	number	Precision grid cell size for snapping vertices. If 0 or when not defined, the highest precision is used (IEE754 double), which provides almost 16 decimal digits of precision. If nonzero, input as well as resulting coordinates will be snapped to a precision grid of that size.

Returns

Geometry

A new geometry representing the intersection

Examples

intersection of two polygons

const a = polygon([ [ [ 0, 4 ], [ 5, 5 ], [ 4, 0 ], [ 0, 4 ] ] ]);
const b = polygon([ [ [ 0, 0 ], [ 5, 6 ], [ 9, 5 ], [ 0, 0 ] ] ]);
const ab_int = intersection(a, b);
const ab_int_pg = intersection(a, b, { gridSize: 0.1 });
const ba_int = intersection(b, a);

const a = polygon([ [ [ 0, 4 ], [ 5, 5 ], [ 4, 0 ], [ 0, 4 ] ] ]); const b = polygon([ [ [ 0, 0 ], [ 5, 6 ], [ 9, 5 ], [ 0, 0 ] ] ]); const ab_int = intersection(a, b); const ab_int_pg = intersection(a, b, { gridSize: 0.1 }); const ba_int = intersection(b, a);

intersection of two lines

const a = fromWKT('LINESTRING (0 0, 10 10)');
const b = fromWKT('LINESTRING (0 1, 10 4)');
const ab_int = intersection(a, b); // 'POINT (1.4285714285714286 1.4285714285714286)'
const ab_int_pg = intersection(a, b, { gridSize: 1e-6 }); // 'POINT (1.428571 1.428571)'

const a = fromWKT('LINESTRING (0 0, 10 10)'); const b = fromWKT('LINESTRING (0 1, 10 4)'); const ab_int = intersection(a, b); // 'POINT (1.4285714285714286 1.4285714285714286)' const ab_int_pg = intersection(a, b, { gridSize: 1e-6 }); // 'POINT (1.428571 1.428571)'