/**
* Get the envelope flag indicator
*
* <p>1 for xy, 2 for xyz, 3 for xym, 4 for xyzm (null would be 0)
*
* @return
*/
public static int getIndicator(GeometryEnvelope envelope) {
int indicator = 1;
if (envelope.hasZ()) {
indicator++;
}
if (envelope.hasM()) {
indicator += 2;
}
return indicator;
}
/**
* Read the envelope based upon the indicator value
*
* @param envelopeIndicator
* @param reader
* @return
*/
private GeometryEnvelope readEnvelope(int envelopeIndicator, ByteReader reader) {
GeometryEnvelope envelope = null;
if (envelopeIndicator > 0) {
// Read x and y values and create envelope
double minX = reader.readDouble();
double maxX = reader.readDouble();
double minY = reader.readDouble();
double maxY = reader.readDouble();
boolean hasZ = false;
Double minZ = null;
Double maxZ = null;
boolean hasM = false;
Double minM = null;
Double maxM = null;
// Read z values
if (envelopeIndicator == 2 || envelopeIndicator == 4) {
hasZ = true;
minZ = reader.readDouble();
maxZ = reader.readDouble();
}
// Read m values
if (envelopeIndicator == 3 || envelopeIndicator == 4) {
hasM = true;
minM = reader.readDouble();
maxM = reader.readDouble();
}
envelope = new GeometryEnvelope(hasZ, hasM);
envelope.setMinX(minX);
envelope.setMaxX(maxX);
envelope.setMinY(minY);
envelope.setMaxY(maxY);
if (hasZ) {
envelope.setMinZ(minZ);
envelope.setMaxZ(maxZ);
}
if (hasM) {
envelope.setMinM(minM);
envelope.setMaxM(maxM);
}
}
return envelope;
}
/**
* Write the envelope bytes
*
* @param writer
* @throws IOException
*/
private void writeEnvelope(ByteWriter writer) throws IOException {
if (envelope != null) {
// Write x and y values
writer.writeDouble(envelope.getMinX());
writer.writeDouble(envelope.getMaxX());
writer.writeDouble(envelope.getMinY());
writer.writeDouble(envelope.getMaxY());
// Write z values
if (envelope.hasZ()) {
writer.writeDouble(envelope.getMinZ());
writer.writeDouble(envelope.getMaxZ());
}
// Write m values
if (envelope.hasM()) {
writer.writeDouble(envelope.getMinM());
writer.writeDouble(envelope.getMaxM());
}
}
}