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/*
* Copyright (c) 2011 Mikant
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
using System.IO;
using GS.Geometry.Files;
namespace GS.Geometry.Files.Tests {
internal class Program {
static void Main(string[] args) {
// open *.slg file
SLG slg = new SLG(@"C:\Users\Mikant\Desktop\LSUD\Sims\Logs\Sonar\sonar.slg");
// get first data record
SLG.Chunk chunk = slg[0];
// define if Depth data exists in the first data record
// (unnecessary: if data doesn't exist depth would be returned as zero)
bool depthExists = chunk.DataExists(SLG.DataField.Depth);
// get the depth
float depth = chunk.Depth;
}
}
}
namespace GS.Geometry.Files {
public class SLG {
private readonly int _format;
private readonly int _bytesPerChunk;
private readonly Chunk[] _chunks;
public SLG(string fileName) {
// note: this wouldn't work for a corruped file
// no exception handling or data validation mechanisms used
using (BinaryReader reader = new BinaryReader(File.OpenRead(fileName))) {
_format = reader.ReadInt32();
_bytesPerChunk = reader.ReadInt32();
var terminal = reader.ReadInt16();
int headerLength = (int)(reader.BaseStream.Position);
_chunks = new Chunk[(int)((reader.BaseStream.Length - headerLength) / _bytesPerChunk)];
for (int i = 0; i < _chunks.Length; i++)
_chunks[i] = new Chunk(reader, _bytesPerChunk);
}
}
public Chunk this[int index] {
get { return _chunks[index]; }
}
public class Chunk {
private readonly DataField _mask;
private readonly float _waterTemp;
private readonly float _waterSpeed;
private readonly float _lowerLimit;
private readonly float _depth;
private readonly float _surfaceDepth;
private readonly float _topOfBottomDepth;
private readonly int _timeOffset;
private readonly int _positionX;
private readonly int _positionY;
private readonly float _speed;
private readonly float _track;
private readonly float _altitude;
private readonly byte[] _data;
private readonly short _sampleRate;
public bool DataExists(DataField field) {
return (_mask & field) != 0;
}
public Chunk(BinaryReader reader, int length) {
long start = reader.BaseStream.Position;
// this mask defines available fields in the chunk
_mask = (DataField)reader.ReadInt16();
_lowerLimit = DataExists(DataField.LowerLimit) ? reader.ReadSingle() : 0;
_depth = DataExists(DataField.Depth) ? reader.ReadSingle() : 0;
_waterTemp = DataExists(DataField.WaterTemp) ? reader.ReadSingle() : 0;
_waterSpeed = DataExists(DataField.WaterSpeed) ? reader.ReadSingle() : 0;
// this data is stored in Mercator Meter format
// see http://www.colby.edu/chemistry/Colby%20Compass/AcqBathometricData.pdf
// for disambiguation. there is a convertion algorithm =)
_positionX = DataExists(DataField.Position) ? reader.ReadInt32() : 0;
_positionY = DataExists(DataField.Position) ? reader.ReadInt32() : 0;
_surfaceDepth = DataExists(DataField.SurfaceDepth) ? reader.ReadSingle() : 0;
_topOfBottomDepth = DataExists(DataField.TopOfBottomDepth) ? reader.ReadSingle() : 0;
_timeOffset = DataExists(DataField.TimeOffset) ? reader.ReadInt32() : 0;
_speed = DataExists(DataField.Speed) ? reader.ReadSingle() : 0;
_track = DataExists(DataField.Track) ? reader.ReadSingle() : 0;
_altitude = DataExists(DataField.Altitude) ? reader.ReadSingle() : 0;
// magic number: its name's a presumption
_sampleRate = reader.ReadInt16();
// in my case _sampleRate was always set to 2400
// at first I thought it is '_data.Length', but it's not:
// in some cases _data.Length was < 2400
//if (_sampleRate != 2400)
// throw new Exception();
int headerLength = (int)(reader.BaseStream.Position - start);
_data = reader.ReadBytes(length - headerLength);
}
#region Properties
public float WaterTemp {
get { return _waterTemp; }
}
public float WaterSpeed {
get { return _waterSpeed; }
}
public float LowerLimit {
get { return _lowerLimit; }
}
public float Depth {
get { return _depth; }
}
public float SurfaceDepth {
get { return _surfaceDepth; }
}
public float TopOfBottomDepth {
get { return _topOfBottomDepth; }
}
public int TimeOffset {
get { return _timeOffset; }
}
public int PositionX {
get { return _positionX; }
}
public int PositionY {
get { return _positionY; }
}
public float Speed {
get { return _speed; }
}
public float Track {
get { return _track; }
}
public float Altitude {
get { return _altitude; }
}
public byte[] Data {
get { return _data; }
}
#endregion
}
// not sure about exact flags,
// because I had only one *.slg file with
// 3 different flag groups
public enum DataField : short {
// it is meant that WaterTemp flag is one of
// 16 or 128, and WaterSpeed flag is another
WaterTemp = 16 | 128,
WaterSpeed = 16 | 128,
// 3 flags and 5 fields (2 groups needed)
LowerLimit = 1024 | 2048 | 8192,
Depth = 1024 | 2048 | 8192,
SurfaceDepth = 1024 | 2048 | 8192,
TopOfBottomDepth = 1024 | 2048 | 8192,
TimeOffset = 1024 | 2048 | 8192,
// 3 flags and 4 fields (1 group more needed)
Position = 4 | 256 | 16384, // grouped: PositionX & PositionY
Speed = 4 | 256 | 16384,
Track = 4 | 256 | 16384,
Altitude = 4 | 256 | 16384,
Unused = 1 | 2 | 8 | 32 | 64 | 512 | 4096 | 16384
}
}
}
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