addLineEndCap method

void addLineEndCap(Coordinate p0, Coordinate p1)

Add an end cap around point p1, terminating a line segment coming from p0

Implementation

void addLineEndCap(Coordinate p0, Coordinate p1) {
  LineSegment seg = new LineSegment.fromCoordinates(p0, p1);

  LineSegment offsetL = new LineSegment.empty();
  computeOffsetSegment(seg, Position.LEFT, distance, offsetL);
  LineSegment offsetR = new LineSegment.empty();
  computeOffsetSegment(seg, Position.RIGHT, distance, offsetR);

  double dx = p1.x - p0.x;
  double dy = p1.y - p0.y;
  double angle = math.atan2(dy, dx);

  switch (bufParams.getEndCapStyle()) {
    case BufferParameters.CAP_ROUND:
      // add offset seg points with a fillet between them
      segList.addPt(offsetL.p1);
      addDirectedFillet(p1, angle + math.pi / 2, angle - math.pi / 2,
          Orientation.CLOCKWISE, distance);
      segList.addPt(offsetR.p1);
      break;
    case BufferParameters.CAP_FLAT:
      // only offset segment points are added
      segList.addPt(offsetL.p1);
      segList.addPt(offsetR.p1);
      break;
    case BufferParameters.CAP_SQUARE:
      // add a square defined by extensions of the offset segment endpoints
      Coordinate squareCapSideOffset = new Coordinate.empty2D();
      squareCapSideOffset.x = distance.abs() * math.cos(angle);
      squareCapSideOffset.y = distance.abs() * math.sin(angle);

      Coordinate squareCapLOffset = new Coordinate(
          offsetL.p1.x + squareCapSideOffset.x,
          offsetL.p1.y + squareCapSideOffset.y);
      Coordinate squareCapROffset = new Coordinate(
          offsetR.p1.x + squareCapSideOffset.x,
          offsetR.p1.y + squareCapSideOffset.y);
      segList.addPt(squareCapLOffset);
      segList.addPt(squareCapROffset);
      break;
  }
}