coordinatesystemwktreader.cs

Sharp Map 用于制作GIS系统S harp Map 用于制作GIS系统S harp Map 用于制作GIS系统

// Copyright 2005, 2006 - Morten Nielsen (www.iter.dk)
//
// This file is part of SharpMap.
// SharpMap is free software; you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
// 
// SharpMap is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Lesser General Public License for more details.

// You should have received a copy of the GNU Lesser General Public License
// along with SharpMap; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 

// SOURCECODE IS MODIFIED FROM ANOTHER WORK AND IS ORIGINALLY BASED ON GeoTools.NET:
/*
 *  Copyright (C) 2002 Urban Science Applications, Inc. 
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

using System;
using System.IO;
using System.Collections.Generic;
using SharpMap.CoordinateSystems;

namespace SharpMap.Converters.WellKnownText
{
	/// <summary>
	/// Creates an object based on the supplied Well Known Text (WKT).
	/// </summary>
	public class CoordinateSystemWktReader
	{
		/// <summary>
		/// Reads and parses a WKT-formatted projection string.
		/// </summary>
		/// <param name="wkt">String containing WKT.</param>
		/// <returns>Object representation of the WKT.</returns>
		/// <exception cref="System.ArgumentException">If a token is not recognised.</exception>
		public static IInfo Parse(string wkt)
		{
			IInfo returnObject = null;
			StringReader reader = new StringReader(wkt);
			WktStreamTokenizer tokenizer = new WktStreamTokenizer(reader);
			tokenizer.NextToken();
			string objectName = tokenizer.GetStringValue();
			switch (objectName)
			{
				case "UNIT":
					returnObject = ReadUnit(tokenizer);
					break;
				//case "VERT_DATUM":
				//    IVerticalDatum verticalDatum = ReadVerticalDatum(tokenizer);
				//    returnObject = verticalDatum;
				//    break;
				case "SPHEROID":
					returnObject = ReadEllipsoid(tokenizer);
					break;
				case "DATUM":
					returnObject = ReadHorizontalDatum(tokenizer); ;
					break;
				case "PRIMEM":
					returnObject = ReadPrimeMeridian(tokenizer);
					break;
				case "VERT_CS":
				case "GEOGCS":
				case "PROJCS":
				case "COMPD_CS":
				case "GEOCCS":
				case "FITTED_CS":
				case "LOCAL_CS":
					returnObject = ReadCoordinateSystem(wkt, tokenizer);
					break;
				default:
					throw new ArgumentException(String.Format("'{0'} is not recongnized.", objectName));

			}
			reader.Close();
			return returnObject;
		}

		/// <summary>
		/// Returns a IUnit given a piece of WKT.
		/// </summary>
		/// <param name="tokenizer">WktStreamTokenizer that has the WKT.</param>
		/// <returns>An object that implements the IUnit interface.</returns>
		private static IUnit ReadUnit(WktStreamTokenizer tokenizer)
		{
			tokenizer.ReadToken("[");
			string unitName = tokenizer.ReadDoubleQuotedWord();
			tokenizer.ReadToken(",");
			tokenizer.NextToken();
			double unitsPerUnit = tokenizer.GetNumericValue();
			string authority = String.Empty;
			long authorityCode = -1;
			tokenizer.NextToken();
			if (tokenizer.GetStringValue() == ",")
			{
				tokenizer.ReadAuthority(ref authority, ref authorityCode);
				tokenizer.ReadToken("]");
			}
			return new Unit(unitsPerUnit, unitName, authority, authorityCode, String.Empty, String.Empty, String.Empty);
		}
		/// <summary>
		/// Returns a <see cref="LinearUnit"/> given a piece of WKT.
		/// </summary>
		/// <param name="tokenizer">WktStreamTokenizer that has the WKT.</param>
		/// <returns>An object that implements the IUnit interface.</returns>
		private static ILinearUnit ReadLinearUnit(WktStreamTokenizer tokenizer)
		{
			tokenizer.ReadToken("[");
			string unitName = tokenizer.ReadDoubleQuotedWord();
			tokenizer.ReadToken(",");
			tokenizer.NextToken();
			double unitsPerUnit = tokenizer.GetNumericValue();
			string authority = String.Empty;
			long authorityCode = -1;
			tokenizer.NextToken();
			if (tokenizer.GetStringValue() == ",")
			{
				tokenizer.ReadAuthority(ref authority, ref authorityCode);
				tokenizer.ReadToken("]");
			}
			return new LinearUnit(unitsPerUnit, unitName, authority, authorityCode, String.Empty, String.Empty, String.Empty);
		}
		/// <summary>
		/// Returns a <see cref="AngularUnit"/> given a piece of WKT.
		/// </summary>
		/// <param name="tokenizer">WktStreamTokenizer that has the WKT.</param>
		/// <returns>An object that implements the IUnit interface.</returns>
		private static IAngularUnit ReadAngularUnit(WktStreamTokenizer tokenizer)
		{
			tokenizer.ReadToken("[");
			string unitName = tokenizer.ReadDoubleQuotedWord();
			tokenizer.ReadToken(",");
			tokenizer.NextToken();
			double unitsPerUnit = tokenizer.GetNumericValue();
			string authority = String.Empty;
			long authorityCode = -1;
			tokenizer.NextToken();
			if (tokenizer.GetStringValue() == ",")
			{
				tokenizer.ReadAuthority(ref authority, ref authorityCode);
				tokenizer.ReadToken("]");
			}
			return new AngularUnit(unitsPerUnit, unitName, authority, authorityCode, String.Empty, String.Empty, String.Empty);
		}

		/// <summary>
		/// Returns a <see cref="AxisInfo"/> given a piece of WKT.
		/// </summary>
		/// <param name="tokenizer">WktStreamTokenizer that has the WKT.</param>
		/// <returns>An AxisInfo object.</returns>
		private static AxisInfo ReadAxis(WktStreamTokenizer tokenizer)
		{
			if (tokenizer.GetStringValue() != "AXIS")
				tokenizer.ReadToken("AXIS");
			tokenizer.ReadToken("[");
			string axisName = tokenizer.ReadDoubleQuotedWord();
			tokenizer.ReadToken(",");
			tokenizer.NextToken();
			string unitname = tokenizer.GetStringValue();
			tokenizer.ReadToken("]");
			switch (unitname.ToUpper())
			{
				case "DOWN": return new AxisInfo(axisName, AxisOrientationEnum.Down);
				case "EAST": return new AxisInfo(axisName, AxisOrientationEnum.East);
				case "NORTH": return new AxisInfo(axisName, AxisOrientationEnum.North);
				case "OTHER": return new AxisInfo(axisName, AxisOrientationEnum.Other);
				case "SOUTH": return new AxisInfo(axisName, AxisOrientationEnum.South);
				case "UP": return new AxisInfo(axisName, AxisOrientationEnum.Up);
				case "WEST": return new AxisInfo(axisName, AxisOrientationEnum.West);
				default:
					throw new ArgumentException("Invalid axis name '" + unitname + "' in WKT");
			}
		}


		/// <summary>
		/// 
		/// </summary>
		/// <param name="coordinateSystem"></param>
		/// <param name="tokenizer"></param>
		/// <returns></returns>
		private static ICoordinateSystem ReadCoordinateSystem(string coordinateSystem, WktStreamTokenizer tokenizer)
		{
			switch (tokenizer.GetStringValue())
			{
				case "GEOGCS":
					return ReadGeographicCoordinateSystem(tokenizer);
				case "PROJCS":
					return ReadProjectedCoordinateSystem(tokenizer);
				case "COMPD_CS":
				/*	ICompoundCoordinateSystem compoundCS = ReadCompoundCoordinateSystem(tokenizer);
					returnCS = compoundCS;
					break;*/
				case "VERT_CS":
				/*	IVerticalCoordinateSystem verticalCS = ReadVerticalCoordinateSystem(tokenizer);
					returnCS = verticalCS;
					break;*/
				case "GEOCCS":
				case "FITTED_CS":
				case "LOCAL_CS":
					throw new NotSupportedException(String.Format("{0} coordinate system is not supported.", coordinateSystem));
				default:
					throw new InvalidOperationException(String.Format("{0} coordinate system is not recognized.", coordinateSystem));
			}				
		}

		/// <summary>
		/// Reads either 3, 6 or 7 parameter Bursa-Wolf values from TOWGS84 token
		/// </summary>
		/// <param name="tokenizer"></param>
		/// <returns></returns>
		private static Wgs84ConversionInfo ReadWGS84ConversionInfo(WktStreamTokenizer tokenizer)
		{
			//TOWGS84[0,0,0,0,0,0,0]
			tokenizer.ReadToken("[");
			Wgs84ConversionInfo info = new Wgs84ConversionInfo();
			tokenizer.NextToken();
			info.Dx = tokenizer.GetNumericValue();
			tokenizer.ReadToken(",");

			tokenizer.NextToken();
			info.Dy = tokenizer.GetNumericValue();
			tokenizer.ReadToken(",");

			tokenizer.NextToken();
			info.Dz = tokenizer.GetNumericValue();
			tokenizer.NextToken();
			if (tokenizer.GetStringValue() == ",")
			{
				tokenizer.NextToken();
				info.Ex = tokenizer.GetNumericValue();

				tokenizer.ReadToken(",");
				tokenizer.NextToken();
				info.Ey = tokenizer.GetNumericValue();

				tokenizer.ReadToken(",");
				tokenizer.NextToken();
				info.Ez = tokenizer.GetNumericValue();

				tokenizer.NextToken();
				if (tokenizer.GetStringValue() == ",")
				{
					tokenizer.NextToken();
					info.Ppm = tokenizer.GetNumericValue();
				}
			}
			if (tokenizer.GetStringValue() != "]")
				tokenizer.ReadToken("]");
			return info;
		}


		/*
		/// <summary>
		/// 
		/// </summary>
		/// <param name="tokenizer"></param>
		/// <returns></returns>
		private static ICompoundCoordinateSystem ReadCompoundCoordinateSystem(WktStreamTokenizer tokenizer)
		{
			
			//COMPD_CS[
			//"OSGB36 / British National Grid + ODN",
			//PROJCS[]
			//VERT_CS[]
			//AUTHORITY["EPSG","7405"]
			//]

			tokenizer.ReadToken("[");
			string name=tokenizer.ReadDoubleQuotedWord();
			tokenizer.ReadToken(",");
			tokenizer.NextToken();
			string headCSCode =  tokenizer.GetStringValue();
			ICoordinateSystem headCS = ReadCoordinateSystem(headCSCode,tokenizer);
			tokenizer.ReadToken(",");
			tokenizer.NextToken();
			string tailCSCode =  tokenizer.GetStringValue();
			ICoordinateSystem tailCS = ReadCoordinateSystem(tailCSCode,tokenizer);
			tokenizer.ReadToken(",");
			string authority=String.Empty;
			string authorityCode=String.Empty; 
			tokenizer.ReadAuthority(ref authority, ref authorityCode);
			tokenizer.ReadToken("]");
			ICompoundCoordinateSystem compoundCS = new CompoundCoordinateSystem(headCS,tailCS,String.Empty,authority,authorityCode,name,String.Empty,String.Empty); 
			return compoundCS;
			
		}*/

		/// <summary>
		/// 
		/// </summary>
		/// <param name="tokenizer"></param>
		/// <returns></returns>
		private static IEllipsoid ReadEllipsoid(WktStreamTokenizer tokenizer)