/// <summary>
/// Gets the axis order for *all* EPSG defined coordinate reference systems with an srid less than 32768
/// </summary>
/// <param name="identifier">The identifier</param>
/// <returns>The axis order</returns>
public int[] this[CrsIdentifier identifier]
{
get
{
switch (identifier.Authority.ToUpper())
{
//case "OGC":
default:
return(Natural);
case "EPSG":
var code = int.Parse(identifier.Identifier);
if (code == 900913)
{
code = 3857;
}
if (code < 0)
{
throw new ArgumentException("Invalid Epsg identifier");
}
var byteIndex = code / 8;
var bitIndex = code % 8;
var flag = 1 << bitIndex;//1 << (7 - bitIndex);
return((EpsgAxisOrderBitField[byteIndex] & flag) == flag ? Geographic : Natural);
}
}
}
public UnitOfMeasure this[CrsIdentifier identifier]
{
get
{
switch (identifier.Authority.ToUpper())
{
case "OGC":
if (identifier.Equals(WellKnownScaleSets.CRS84))
{
return(this[9102]);
}
return(this[9001]);
case "EPSG":
return(this[SeekUom(int.Parse(identifier.Identifier))]);
}
throw new ArgumentException("identifier");
}
}
/// <summary>
/// Gets the axis order for *all* EPSG defined coordinate reference systems with an srid less than 32768
/// </summary>
/// <param name="identifier">The identifier</param>
/// <returns>The axis order</returns>
public int[] this[CrsIdentifier identifier]
{
get
{
const int
maxSrid = 32767; // PDD: I don't know where this number comes from. I based it on the comment below.
switch (identifier.Authority.ToUpper())
{
//case "OGC":
default:
return(Natural);
case "EPSG":
var code = int.Parse(identifier.Identifier);
if (code == 900913)
{
code = 3857;
}
if (code < 0)
{
throw new ArgumentException("Invalid Epsg identifier");
}
if (code > maxSrid)
{
return(Natural); // Default to Natural because this is the most common case.
}
else
{
var byteIndex = code / 8;
var bitIndex = code % 8;
var flag = 1 << bitIndex; //1 << (7 - bitIndex);
return((EpsgAxisOrderBitField[byteIndex] & flag) == flag ? Geographic : Natural);
}
}
}
}
/// <summary>
/// Creates an instance for this class
/// </summary>
/// <param name="name"></param>
/// <param name="crs"></param>
/// <param name="items"></param>
public ScaleSet(string name, CrsIdentifier crs, IEnumerable <ScaleSetItem> items)
{
Name = name;
Crs = crs;
_items = items.ToArray();
}
private static List <ITileSchema> GetTileMatrixSets(IEnumerable <TileMatrixSet> tileMatrixSets,
BoundingBoxAxisOrderInterpretation bbaoi)
{
// Get a set of well known scale sets. For these we don't need to have
var wkss = new WellKnownScaleSets();
// Axis order registry
var crsAxisOrder = new CrsAxisOrderRegistry();
// Unit of measure registry
var crsUnitOfMeasure = new CrsUnitOfMeasureRegistry();
var tileSchemas = new List <ITileSchema>();
foreach (var tileMatrixSet in tileMatrixSets)
{
// Check if a Well-Known scale set is used, either by Identifier or WellKnownScaleSet property
var ss = wkss[tileMatrixSet.Identifier.Value];
if (ss == null && !string.IsNullOrEmpty(tileMatrixSet.WellKnownScaleSet))
{
ss = wkss[tileMatrixSet.WellKnownScaleSet.Split(':').Last()];
}
// Try to parse the Crs
var supportedCrs = tileMatrixSet.SupportedCRS;
// Hack to fix broken crs spec
supportedCrs = supportedCrs.Replace("6.18:3", "6.18.3");
CrsIdentifier crs;
if (!CrsIdentifier.TryParse(supportedCrs, out crs))
{
// If we cannot parse the crs, we cannot compute tile schema, thus ignore.
// ToDo: Log this
continue;
}
// Get the ordinate order for the crs (x, y) or (y, x) aka (lat, long)
var ordinateOrder = crsAxisOrder[crs];
// Get the unit of measure for the crs
var unitOfMeasure = crsUnitOfMeasure[crs];
// Create a new WMTS tile schema
var tileSchema = new WmtsTileSchema();
// Add the resolutions
foreach (var tileMatrix in tileMatrixSet.TileMatrix)
{
tileSchema.Resolutions.Add(ToResolution(tileMatrix, ordinateOrder, unitOfMeasure.ToMeter, ss));
}
tileSchema.Extent = ToExtent(tileMatrixSet, tileSchema, GetOrdinateOrder(bbaoi, ordinateOrder));
// Fill in the remaining properties
tileSchema.Name = tileMatrixSet.Identifier.Value;
tileSchema.YAxis = YAxis.OSM;
tileSchema.Srs = supportedCrs;
tileSchema.SupportedSRS = crs;
// record the tile schema
tileSchemas.Add(tileSchema);
}
return(tileSchemas);
}