/// <summary>
/// Load a GAT file
/// </summary>
/// <param name="data">GAT file data</param>
public static GAT Load(BinaryReader data)
{
string header = data.ReadBinaryString(4);
//check for valid gat file
if (!string.Equals(header, GAT.Header))
{
throw new Exception("AltitudeLoader.Load: Header (" + header + ") is not \"GRAT\"");
}
//load parameters
string version = Convert.ToString(data.ReadUByte());
string subversion = Convert.ToString(data.ReadUByte());
version += "." + subversion;
uint width = data.ReadULong();
uint height = data.ReadULong();
GAT.Cell[] cells = new GAT.Cell[width * height];
//load the cells
for (int i = 0; i < width * height; i++)
{
Vector4 heights = new Vector4();
heights[0] = data.ReadFloat() * 0.2f; // height 1
heights[1] = data.ReadFloat() * 0.2f; // height 2
heights[2] = data.ReadFloat() * 0.2f; // height 3
heights[3] = data.ReadFloat() * 0.2f; // height 4
cells[i].Heights = heights;
cells[i].type = GAT.TYPE_TABLE[data.ReadULong()]; // type
}
//exports
return(new GAT(width, height, cells, version));
}
/// <summary>
/// Return cell height
/// </summary>
/// <param name="x">x position</param>
/// <param name="y">y position</param>
/// <returns>cell height</returns>
public double GetCellHeight(double x, double y)
{
if (gat.cells == null)
{
return(0);
}
/* DIFF robrowser adds 0.5 to each coordinate here */
GAT.Cell cell = GetCell(x, y);
// Should be at the middle of the cell
x %= 1.0;
y %= 1.0;
double x1 = cell.Heights[0] + (cell.Heights[1] - cell.Heights[0]) * x;
double x2 = cell.Heights[2] + (cell.Heights[3] - cell.Heights[2]) * x;
return(-(x1 + (x2 - x1) * y));
}
