Application: gvSIG desktop

/*******************************************************************************

LASVariableLengthRecord.java

Copyright (C) 2008 by DIELMO 3D S.L.

This program is free software; you can redistribute it and/or modify

it under the terms of the GNU General Public License as published by

the Free Software Foundation; either version 2 of the License, or

(at your option) any later version.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

GNU General Public License for more details.

You should have received a copy of the GNU General Public License

along with this program; if not, write to the Free Software

Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

*******************************************************************************/

package com.dielmo.gvsig.lidar;

import java.io.*;

import java.nio.ByteBuffer;

import javax.swing.JOptionPane;

import com.iver.andami.PluginServices;

import com.iver.cit.gvsig.fmap.drivers.dgn.ByteUtils;

public class LASVariableLengthRecord_V10 extends LASVariableLengthRecord_1X {        

        /**

         * file Signature, must contain AABB in version LAS1.0, while in version LAS1.1

         * it is a reserved field.

         */

        private int recordSignature;

        /**

         * Default constructor, without arguments.

         * Initializes all components to zero.

         */ 

        public LASVariableLengthRecord_V10() {

                super();

                recordSignature = 0;

        }

        /**

         * Return record signature. This must be always "AABB" in version LAS1.0

         * This field is reserved in LAS1.1

         * 

         * @return record signature

         */

        public int getRecordSignature() {        

                return recordSignature;

        }

        /**

         * Read the variable length record

         * 

         * @param input input file to read

         * @param VarLengthRecord buffer into which the data is read 

         * @return true if success else return false 

         */

        public boolean readVarLegthRecord(InputStream input, byte[] VarLengthRecord) {

                if(RecordLengthAfterHeader <= 0) {

                        return false;

                }

                try {

                        VarLengthRecord = new byte[RecordLengthAfterHeader];

                        int offset=0,numRead=0;

                        while (offset < RecordLengthAfterHeader && (numRead = input.read(VarLengthRecord, offset, RecordLengthAfterHeader-offset) ) >= 0) {

                             offset += numRead;

                        }

                    if (offset < RecordLengthAfterHeader) {

                            JOptionPane.showMessageDialog(null, PluginServices.getText(this, "bad_input_format"));

                            return false;

                        }

                } catch(IOException e) {

                        e.printStackTrace();

                        return false;

                }

                return true;                        

        }

        /**

         * Read the Variable length record header of LAS file

         * 

         * @param input input file to read

         * @return true if success else return false 

         */

        public boolean readVarLegthRecordHeader(InputStream input) {

                int offset=0,numRead=0, j; 

                byte[] VarLengthRecord = new byte[54];

                //read VarLenhRecord

              try {

                        while (offset < 54 && (numRead = input.read(VarLengthRecord, offset, VarLengthRecord.length-offset) ) >= 0) {

                             offset += numRead;

                        }

                    if (offset < VarLengthRecord.length) {

                            JOptionPane.showMessageDialog(null, PluginServices.getText(this, "bad_input_format"));

                            return false;

                        }

                    recordSignature = ByteUtilities.arr2Unsignedshort(VarLengthRecord, 0);

                    if(recordSignature != 43707) {

                            return false;

                    }

                    for(j=0;j<16;j++)

                                userID[j] = (char)(VarLengthRecord[j+2] & 0xFF);

                        recordID = ByteUtilities.arr2Unsignedshort(VarLengthRecord, 18);

                        RecordLengthAfterHeader = ByteUtilities.arr2Unsignedshort(VarLengthRecord, 20);

                        for(j=0;j<32;j++)

                                description[j] = (char)(VarLengthRecord[j+22] & 0xFF);

                } catch (IOException e) {

                        // TODO Auto-generated catch block

                        e.printStackTrace();

                        return false;

                }

                return true;

        }

        public boolean writeVarLegthRecordHeader(ByteBuffer bb) {

                int i;

                int index=0;

                byte[] VL_Buffer = new byte[54];

                byte[] aux = new byte[8];

                int[] begin = new int[1];

            if(recordSignature != 43707) {

                        return false;

                }

            // recordSignature bytes 0-2

            begin[0] = 0;

                i=3;

                ByteUtils.intToBytes(recordSignature, aux, begin);

                for(index=0;index<2;index++) {

                        VL_Buffer[index] = aux[i];

                        i--;

                }

                // userID bytes 2-18

                i = 0;

                for(index=2;index<18;index++) {

                        VL_Buffer[index] = ((byte)(userID[i] & 0XFF));

                        i++;

                }

                // recordID bytes 18-20

                begin[0] = 0;

                i=3;

                ByteUtils.intToBytes(recordID, aux, begin);

                for(index=18;index<20;index++) {

                        VL_Buffer[index] = aux[i];

                        i--;

                }

                // RecordLengthAfterHeader bytes 20-22

                begin[0] = 0;

                i=3;

                ByteUtils.intToBytes(RecordLengthAfterHeader, aux, begin);

                for(index=20;index<22;index++) {

                        VL_Buffer[index] = aux[i];

                        i--;

                }

                // description bytes 22-54

                i = 0;

                for(index=22;index<54;index++) {

                        VL_Buffer[index] = ((byte)(description[i] & 0XFF));

                        i++;

                }

                bb.put(VL_Buffer);

                return true;

        }

}