/** @param recBuf */
public SHPPolyLine3D(byte[] recBuf) {
super(recBuf);
int pointsStart = 0;
int sumPoints = 0;
envelope = ShapeUtils.readBox(recBuf, 4);
numParts = ByteUtils.readLEInt(recBuffer, 36);
numPoints = ByteUtils.readLEInt(recBuffer, 40);
pointsStart = ShapeConst.PARTS_START + (numParts * 4);
points = new SHPPoint[numParts][];
for (int j = 0; j < numParts; j++) {
int firstPointNo = 0;
int nextFirstPointNo = 0;
int offset = 0;
int lnumPoints = 0;
// get number of first point of current part out of ESRI shape Record:
firstPointNo = ByteUtils.readLEInt(recBuffer, ShapeConst.PARTS_START + (j * 4));
// calculate offset of part in bytes, count from the beginning of recordbuffer
offset = pointsStart + (firstPointNo * 16);
// get number of first point of next part ...
if (j < numParts - 1) {
// ... usually out of ESRI shape Record
nextFirstPointNo = ByteUtils.readLEInt(recBuffer, ShapeConst.PARTS_START + ((j + 1) * 4));
}
// ... for the last part as total number of points
else if (j == numParts - 1) {
nextFirstPointNo = numPoints;
}
// calculate number of points per part due to distance and
// calculate some checksum for the total number of points to be worked
lnumPoints = nextFirstPointNo - firstPointNo;
sumPoints += lnumPoints;
// allocate memory for the j-th part
points[j] = new SHPPoint[lnumPoints];
int zPos = pointsStart + 16 * numPoints + 16;
// create the points of the j-th part from the buffer
for (int i = 0; i < lnumPoints; i++) {
double z = ByteUtils.readLEDouble(recBuffer, zPos);
zPos += 8;
SHPPoint dummyPoint = new SHPPoint(recBuf, offset + (i * 16));
points[j][i] = new SHPPoint3D(dummyPoint.x, dummyPoint.y, z);
}
}
}
/**
* Reads and parses the header of the file. Values from the header<br>
* are stored in the fields of this class.<br>
*/
private void readHeader() throws IOException {
header = new byte[ShapeConst.SHAPE_FILE_HEADER_LENGTH];
/*
* Make sure we're at the beginning of the file
*/
rafShp.seek(0);
rafShp.read(header, 0, ShapeConst.SHAPE_FILE_HEADER_LENGTH);
int fileCode = ByteUtils.readBEInt(header, 0);
if (fileCode != ShapeConst.SHAPE_FILE_CODE) {
throw new IOException("Invalid file code, " + "probably not a shape file");
}
fileVersion = ByteUtils.readLEInt(header, 28);
if (fileVersion != ShapeConst.SHAPE_FILE_VERSION) {
throw new IOException("Unable to read shape files with version " + fileVersion);
}
fileLength = ByteUtils.readBEInt(header, 24);
/*
* convert from 16-bit words to 8-bit bytes
*/
fileLength *= 2;
fileShapeType = ByteUtils.readLEInt(header, 32);
/*
* read ESRIBoundingBox and convert to SHPEnvelope
*/
fileMBR = new SHPEnvelope(ShapeUtils.readBox(header, 36));
}
