private CoordinateSequence decimate(LiteCoordinateSequence seq) {
double[] coords = seq.getArray();
int numDoubles = coords.length;
int dim = seq.getDimension();
int readDoubles = 0;
double prevx, currx, prevy, curry, diffx, diffy;
for (int currentDoubles = 0; currentDoubles < numDoubles; currentDoubles += dim) {
if (currentDoubles >= dim && currentDoubles < numDoubles - 1) {
prevx = coords[readDoubles - dim];
currx = coords[currentDoubles];
diffx = Math.abs(prevx - currx);
prevy = coords[readDoubles - dim + 1];
curry = coords[currentDoubles + 1];
diffy = Math.abs(prevy - curry);
if (diffx > spanx || diffy > spany) {
readDoubles = copyCoordinate(coords, dim, readDoubles, currentDoubles);
}
} else {
readDoubles = copyCoordinate(coords, dim, readDoubles, currentDoubles);
}
}
double[] newCoords = new double[readDoubles];
System.arraycopy(coords, 0, newCoords, 0, readDoubles);
seq.setArray(newCoords);
return seq;
}
/**
* @param geom
* @param seq
*/
private boolean decimateOnEnvelope(Geometry geom, LiteCoordinateSequence seq) {
Envelope env = geom.getEnvelopeInternal();
if (env.getWidth() <= spanx && env.getHeight() <= spany) {
double[] coords = seq.getArray();
int dim = seq.getDimension();
double[] newcoords = new double[dim * 2];
for (int i = 0; i < dim; i++) {
newcoords[i] = coords[i];
newcoords[dim + i] = coords[coords.length - dim + i];
}
seq.setArray(coords);
return true;
}
return false;
}
