java - 如何在Java JTS中找到给定线段的平行线(源代码行上方和下方的平行线)？

Question

如何在 Java JTS (JTS Topology Suite) 中找到给定线段的平行线(源代码行上方和下方的平行线)？ 输入:我有源线的点(长和纬度) 坐标 1(经、纬度) ---------------------------- 坐标 2(经、纬度)

坐标[]坐标=新坐标(新坐标(经纬度),新坐标(经纬度));

源代码行->

LineSegment sourceLine =new GeometryFactory().createLineString(coordinate);

现在我必须找到一条与源线平行的线，位于其上方和下方。

Answer 1

LineSegment 上有一个 pointAlongOffset(double segmentLengthFraction, double offsetDistance) 方法用于此目的。示例:

// source line from given start and end coordinate
LineSegment sourceLine = new LineSegment(startCoordinate, endCoordinate);

// left from start- to end-point (note negative offset distance!)
Coordinate startLeft = sourceLine.pointAlongOffset(0, -parallelDistance);
Coordinate endLeft = sourceLine.pointAlongOffset(1, -parallelDistance);
LineString leftLine = new GeometryFactory().createLineString(new Coordinate[]{startLeft, endLeft});
// right from start- to end-point (note positive offset distance!)
Coordinate startRight = sourceLine.pointAlongOffset(0, parallelDistance);
Coordinate endRight = sourceLine.pointAlongOffset(1, parallelDistance);
LineString rightLine = new GeometryFactory().createLineString(new Coordinate[]{startRight, endRight});