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| |
| # ST_OffsetCurve |
| |
| Introduction: Returns a line at a given offset distance from a linear geometry. If the distance is positive, the offset is on the left side of the input line; if it is negative, it is on the right side. Returns null for empty geometries. |
| |
| The optional third parameter `quadrantSegments` controls the number of line segments used to approximate a quarter circle at round joins. The default value is 8. |
| |
| Format: `ST_OffsetCurve(geometry: Geometry, distance: Double, quadrantSegments: Integer)` |
| |
| Format: `ST_OffsetCurve(geometry: Geometry, distance: Double)` |
| |
| Return type: `Geometry` |
| |
| SQL Example: |
| |
|  |
| |
| ```sql |
| SELECT ST_AsText(ST_OffsetCurve(ST_GeomFromWKT('LINESTRING(0 0, 10 0, 10 10)'), 5.0)) |
| ``` |
| |
| Output: `LINESTRING (0 5, 5 5, 5 10)` |
| |
| SQL Example: |
| |
|  |
| |
| ```sql |
| SELECT ST_NPoints(ST_OffsetCurve(ST_GeomFromWKT('LINESTRING(0 0, 10 0, 10 10)'), -3.0)) |
| ``` |
| |
| Output: `11` |
| |
| SQL Example: |
| |
|  |
| |
| ```sql |
| SELECT ST_NPoints(ST_OffsetCurve(ST_GeomFromWKT('LINESTRING(0 0, 10 0, 10 10)'), -3.0, 16)) |
| ``` |
| |
| Output: `19` |
