/// <summary>
/// Read a *.dem file
/// </summary>
/// <param name="filename"></param>
public void Read(string filename)
{
StreamReader reader = new StreamReader(filename);
char[] buffer = new char[1024]; // size of A Record
reader.Read(buffer, 0, 1024);
_mARecord = new ARecord();
_mARecord.file_name = ParseString(buffer, 0, 40).ToCharArray();
_mARecord.free_text_format = ParseString(buffer, 40, 40).ToCharArray();
_mARecord.SE_geographic_corner_S = ParseString(buffer, 109, 13).ToCharArray();
_mARecord.SE_geographic_corner_E = ParseString(buffer, 122, 13).ToCharArray();
_mARecord.process_code = buffer[135];
_mARecord.origin_code = ParseString(buffer, 140, 4).ToCharArray();
_mARecord.dem_level_code = ParseInt(buffer, 144);
_mARecord.elevation_pattern = ParseInt(buffer, 150);
_mARecord.ground_ref_system = ParseInt(buffer, 156);
_mARecord.ground_ref_zone = ParseInt(buffer, 162);
for (int i = 0; i < 15; i++)
{
_mARecord.projection[0] = ParseDouble(buffer, 168 + i * 24);
}
_mARecord.ground_unit = ParseInt(buffer, 528);
_mARecord.elevation_unit = ParseInt(buffer, 534);
_mARecord.side_count = ParseInt(buffer, 540);
_mARecord.sw_coord[0] = (float)ParseDouble(buffer, 546); // UTM grid (measured in meters)
_mARecord.sw_coord[1] = (float)ParseDouble(buffer, 570);
_mARecord.nw_coord[0] = (float)ParseDouble(buffer, 594);
_mARecord.nw_coord[1] = (float)ParseDouble(buffer, 618);
_mARecord.ne_coord[0] = (float)ParseDouble(buffer, 642);
_mARecord.ne_coord[1] = (float)ParseDouble(buffer, 666);
_mARecord.se_coord[0] = (float)ParseDouble(buffer, 690);
_mARecord.se_coord[1] = (float)ParseDouble(buffer, 714);
_mARecord.elevation_min = ParseDouble(buffer, 738);
_mARecord.elevation_max = ParseDouble(buffer, 762);
_mARecord.ccw_angle = ParseDouble(buffer, 786);
_mARecord.elevation_accuracy = ParseInt(buffer, 810);
_mARecord.xyz_resolution[0] = ParseFloat(buffer, 816);
_mARecord.xyz_resolution[1] = ParseFloat(buffer, 828);
_mARecord.xyz_resolution[2] = ParseFloat(buffer, 840);
_mARecord.eastings_cols = ParseInt(buffer, 858);
_mARecord.northings_rows = ParseInt(buffer, 858); // WARNING. SHOULD NOT USE THIS VALUE. BUT WE ASSUME IS THE SAME WITH eastings SINCE IT IS ALWAYS THE CASE.
_mARecord.suspect_void = ParseInt(buffer, 886, 2);
_mARecord.percent_void = ParseInt(buffer, 896);
// read the rest of the DEM
StreamTokenizer tokenizer = new StreamTokenizer(reader, new char[] { ' ' });
_mBRecord = null;
for (int col = 0; col < _mARecord.eastings_cols; col++)
{
tokenizer.Next(); // row id
tokenizer.Next(); // col id
_mARecord.northings_rows = ToInt(tokenizer.Next());
if (_mBRecord == null)
{
_mBRecord = new BRecord(_mARecord.eastings_cols, _mARecord.northings_rows);
}
tokenizer.Next(); // skip next six fields
tokenizer.Next();
tokenizer.Next();
tokenizer.Next();
tokenizer.Next();
tokenizer.Next();
// for (int row = record.northings_rows - 1; row >= 0; row--)
for (int row = 0; row < _mARecord.northings_rows; row++)
{
_mBRecord.elevations[col, row] = ToShort(tokenizer.Next());
}
}
reader.Close();
}
public DemDocument()
{
_mARecord = null;
_mBRecord = null;
}
