private bool ReadHeader(byte[] headerBuffer, GridTable table)
{
var ll = new PhiLambda
{
Phi = GetBigEndianDouble(headerBuffer, 4 * 16 + 8),
Lambda = -GetBigEndianDouble(headerBuffer, 7 * 16 + 8)
};
var ur = new PhiLambda
{
Phi = GetBigEndianDouble(headerBuffer, 5 * 16 + 8),
Lambda = -GetBigEndianDouble(headerBuffer, 6 * 16 + 8)
};
var cs = new PhiLambda
{
Phi = GetBigEndianDouble(headerBuffer, 8 * 16 + 8),
Lambda = -GetBigEndianDouble(headerBuffer, 9 * 16 + 8)
};
table.NumLambdas = (int)(Math.Abs(ur.Lambda - ll.Lambda) / cs.Lambda + .5) + 1;
table.NumPhis = (int)(Math.Abs(ur.Phi - ll.Phi) / cs.Phi + .5) + 1;
table.LowerLeft = PhiLambda.DegreesToRadians(ll);
table.UpperRight = PhiLambda.DegreesToRadians(ur);
table.SizeOfGridCell = PhiLambda.DegreesToRadians(cs);
return(true);
}
internal override bool ReadHeader(GridTable table)
{
using (var stream = OpenGridTableStream())
{
var header = new byte[176];
if (stream.Read(header, 0, 176) != 176)
{
return(false);
}
table.LowerLeft = new PhiLambda
{
Phi = GetBigEndianDouble(header, 24),
Lambda = -GetBigEndianDouble(header, 72)
};
table.UpperRight = new PhiLambda
{
Phi = GetBigEndianDouble(header, 40),
Lambda = -GetBigEndianDouble(header, 56)
};
table.SizeOfGridCell = new PhiLambda
{
Phi = GetBigEndianDouble(header, 88),
Lambda = -GetBigEndianDouble(header, 104)
};
var size = table.UpperRight - table.LowerLeft;
table.NumLambdas = (int)(Math.Abs(size.Lambda) / table.SizeOfGridCell.Lambda + 0.5) + 1;
table.NumPhis = (int)(Math.Abs(size.Phi) / table.SizeOfGridCell.Phi + 0.5) + 1;
table.LowerLeft = PhiLambda.DegreesToRadians(table.LowerLeft);
table.UpperRight = PhiLambda.DegreesToRadians(table.UpperRight);
table.SizeOfGridCell = PhiLambda.DegreesToRadians(table.SizeOfGridCell);
return(true);
}
}
/// <summary>
/// Parses the grid table header and returns an appropriate <see cref="GridTable"/>
/// </summary>
/// <param name="table">The grid tabel to initialize</param>
/// <returns>true if the header could be read.</returns>
internal override bool ReadHeader(GridTable table)
{
using (var br = new BinaryReader(OpenGridTableStream()))
{
br.BaseStream.Seek(64, SeekOrigin.Current);
table.NumLambdas = br.ReadInt32();
table.NumPhis = br.ReadInt32();
br.ReadBytes(4);
PhiLambda ll, cs;
ll.Lambda = br.ReadSingle();
cs.Lambda = br.ReadSingle();
ll.Phi = br.ReadSingle();
cs.Phi = br.ReadSingle();
table.LowerLeft = PhiLambda.DegreesToRadians(ll);
table.SizeOfGridCell = PhiLambda.DegreesToRadians(cs);
table.UpperRight = ll + cs.Times(table.NumPhis, table.NumLambdas);
return(true);
}
}
