public static LineString removeRepeatedPoints(final LineString points) {
final int axisCount = points.getAxisCount();
final List<Double> coordinates = new ArrayList<>();
double x = points.getX(0);
double y = points.getY(0);
coordinates.add(x);
coordinates.add(y);
for (int axisIndex = 2; axisIndex < axisCount; axisIndex++) {
coordinates.add(points.getCoordinate(0, axisIndex));
}
for (int i = 0; i < points.getVertexCount(); i++) {
final double x1 = points.getX(i);
final double y1 = points.getY(i);
if (x != x1 || y != y1) {
coordinates.add(x1);
coordinates.add(y1);
for (int axisIndex = 2; axisIndex < axisCount; axisIndex++) {
coordinates.add(points.getCoordinate(i, axisIndex));
}
x = x1;
y = y1;
}
}
return new LineStringDouble(axisCount, coordinates);
}
public static int orientationIndex(
final LineString ring, final int index1, final int index2, final int index) {
return orientationIndex(
ring.getX(index1),
ring.getY(index1),
ring.getX(index2),
ring.getY(index2),
ring.getX(index),
ring.getY(index));
}
public static double angleToNext(final LineString points, final int i) {
final double x1 = points.getX(i);
final double y1 = points.getY(i);
double x2;
double y2;
int j = i + 1;
do {
x2 = points.getX(j);
y2 = points.getY(j);
j++;
} while (x1 == x2 && y1 == y2 && j < points.getVertexCount());
final double angle = Angle.angle2d(x1, y1, x2, y2);
return angle;
}
public static double angleToPrevious(final LineString points, final int i) {
if (i > 0) {
final double x1 = points.getX(i);
final double y1 = points.getY(i);
double x2;
double y2;
int j = i - 1;
do {
x2 = points.getX(j);
y2 = points.getY(j);
j--;
} while (x1 == x2 && y1 == y2 && j > -1);
final double angle = Angle.angle2d(x1, y1, x2, y2);
return angle;
} else {
throw new IllegalArgumentException("Index must be > 0 to calculate previous angle");
}
}
public static int appendReverse(
final int axisCount,
final LineString source,
final int sourceStartIndex,
final double[] targetCoordinates,
final int targetStartIndex,
final int vertexCount) {
int coordIndex = targetStartIndex;
final int sourceVertexCount = source.getVertexCount();
double previousX;
double previousY;
if (targetStartIndex == 0) {
previousX = Double.NaN;
previousY = Double.NaN;
} else {
previousX = targetCoordinates[(targetStartIndex - 1) * axisCount];
previousY = targetCoordinates[(targetStartIndex - 1) * axisCount + 1];
}
int coordinateIndex = coordIndex * axisCount;
int sourceIndex = sourceVertexCount - 1 - sourceStartIndex;
for (int i = 0; i < vertexCount; i++) {
final double x = source.getX(sourceIndex);
final double y = source.getY(sourceIndex);
if (x != previousX || y != previousY) {
targetCoordinates[coordinateIndex++] = x;
targetCoordinates[coordinateIndex++] = y;
for (int axisIndex = 2; axisIndex < axisCount; axisIndex++) {
final double coordinate = source.getCoordinate(sourceIndex, axisIndex);
targetCoordinates[coordinateIndex++] = coordinate;
}
coordIndex++;
}
sourceIndex--;
previousX = x;
previousY = y;
}
return coordIndex;
}