AE中自定义坐标系的参考代码

转载自http://www.blogbus.com/endlessmissing-logs/65641317.html

  在搞AE开发的时候，经常碰到的一个问题就是不同坐标系统之间的转换，AE中IGlobeControl控件中提供了IGlobeViewUtil类实现了大地坐标、屏幕坐标和地理坐标三者之间的转换，IMapControl中则提供了ToMapPoint和FromMapPoint两种方法实现屏幕坐标和地理坐标之间的转换，但在实际开发中，这些转换还不够，比如当我们需要实现地理坐标转换到自定义格式的大地坐标时，上述方法则不能解决这些问题，最好的解决方法是使用IGeometry对象的Project方法，实现不同空间参照系之间的相互转换。以下以地理坐标转为自定义的Albers坐标系统为例予以说明，其主要用到的接口有ISpatialReferenceFactory、IProjectedCoordinateSystem、IProjectedCoordinateSystemEdit、ISpatialReferenceFactory、IGeographicCoordinateSystem 、ISpatialReference 等：
        其C#代码如下：
        //将任意坐标系统转换为自定义Albers大地坐标（米）
        public static IPoint GeoToGra(IPoint point)
        {
            IPoint pt = new PointClass();
            pt.PutCoords(point.X,point.Y);

            ISpatialReferenceFactory2 pFact = new SpatialReferenceEnvironmentClass();

            //定义地理坐标，由输入的对象决定，也可以自己定义，参考： esriSRGeoCSType
            IGeographicCoordinateSystem pGCS = new GeographicCoordinateSystemClass();
            pGCS = pFact.CreateGeographicCoordinateSystem(point.SpatialReference.FactoryCode);
            
            //自定义投影方式
            IProjectedCoordinateSystem pProjectedCS = new ProjectedCoordinateSystemClass();
            IProjectedCoordinateSystemEdit pProjectedCSEdit = pProjectedCS as IProjectedCoordinateSystemEdit;

            //定义投影方式，参考： esriSRProjectionType
            IProjection pProjection = new ProjectionClass();
            pProjection = pFact.CreateProjection((int)esriSRProjectionType.esriSRProjection_Albers);

            //定义投影单位，参考：esriSRUnitType
            ILinearUnit pUnit = new LinearUnitClass();
            pUnit = pFact.CreateUnit((int)esriSRUnitType.esriSRUnit_Meter) as ILinearUnit;

            //定义其他参数，参考：esriSRParameterType
            IParameter[] pParm = new IParameter[6];
            pParm[0] = pFact.CreateParameter((int)esriSRParameterType.esriSRParameter_FalseEasting);
            pParm[0].Value = 0;

            pParm[1] = pFact.CreateParameter((int)esriSRParameterType.esriSRParameter_FalseNorthing);
            pParm[1].Value = 0;

            pParm[2] = pFact.CreateParameter((int)esriSRParameterType.esriSRParameter_CentralMeridian);
            pParm[2].Value = 110;

            pParm[3] = pFact.CreateParameter((int)esriSRParameterType.esriSRParameter_StandardParallel1);
            pParm[3].Value = 25;

            pParm[4] = pFact.CreateParameter((int)esriSRParameterType.esriSRParameter_StandardParallel2);
            pParm[4].Value = 47;

            pParm[5] = pFact.CreateParameter((int)esriSRParameterType.esriSRParameter_LatitudeOfOrigin);
            pParm[5].Value = 0;

            //设置投影相关信息
            object name = "User_Defined_Albers";
            object alias = "Albers";
            object abbreviation = "Albers";
            object remarks = "User_Defined_Albers is the projection";
            object usage = "";
            object gcs = pGCS;
            object projectedUnit = pUnit;
            object projection = pProjection;
            object parameters = pParm;
            pProjectedCSEdit.Define(ref name, ref alias, ref abbreviation, ref remarks, ref usage, ref gcs, ref  projectedUnit, ref projection, ref parameters);

            //获取自定义空间参考
            ISpatialReference pSpatialRef = pProjectedCS as ISpatialReference;
            
            IGeometry pGeometry = (IGeometry)pt;
            pGeometry.SpatialReference = pGCS as ISpatialReference;

            //重投影处理
            pGeometry.Project(pSpatialRef);

            return pt;
        }
        
        //将平面坐标转换为地理坐标WGS1984(经纬度)
        public static IPoint GetGeo(IGeometry pg)
        {
            IPoint pt = new PointClass();
            pt.PutCoords(pg.Envelope.XMax, pg.Envelope.YMax);    //这里IGeometry对象可换成IPoint等对象
            ISpatialReferenceFactory2 spatialReferenceFact = new SpatialReferenceEnvironmentClass();
            IGeometry geo = (IGeometry)pt;
            geo.SpatialReference = spatialReferenceFact.CreateProjectedCoordinateSystem(pg.SpatialReference.FactoryCode);
            ISpatialReference pSR = spatialReferenceFact.CreateGeographicCoordinateSystem((int)esriSRGeoCSType.esriSRGeoCS_WGS1984);
            geo.Project(pSR);               
            return pt;
        }

       以上实现可以参考ESRI提供的相关帮助示例文档：
                IProjectedCoordinateSystemEdit_Define_Example、CreateParameter_Example 、
                ISpatialReferenceFactory_Example、CreateProjection_Example、CreateUnit_Example
                CreateGeographicCoordinateSystem_Example、CreateProjectedCoordinateSystem_Example

      自定义不同的坐标系统，需要设置不同的参数，所有的地图投影都必须有FalseEasting 和 FalseNorthing两个参数，每种不同投影的其他参数的参数如下所示，具体参照：IProjectedCoordinateSystemEdit Interface

Aitoff
CentralMeridian

Albers
CentralMeridian 
StandardParallel1
StandardParallel2
LatitudeOfOrigin

Azimuthal_Equidistant
CentralMeridian 
LatitudeOfOrigin

Behrmann
CentralMeridian

Bonne
CentralMeridian 
StandardParallel1

Cassini
CentralMeridian 
ScaleFactor 
LatitudeOfOrigin

Craster_Parabolic
CentralMeridian

Cylindrical_Equal_Area
CentralMeridian 
StandardParallel1

Double_Stereographic
CentralMeridian 
ScaleFactor 
LatitudeOfOrigin

Eckert_I
CentralMeridian

Eckert_II
CentralMeridian

Eckert_III
CentralMeridian

Eckert_IV
CentralMeridian

Eckert_V
CentralMeridian

Eckert_VI
CentralMeridian

Equidistant_Conic
CentralMeridian 
StandardParallel1
StandardParallel2
LatitudeOfOrigin

Equidistant_Cylindrical
CentralMeridian 
StandardParallel1

Flat_Polar_Quartic
CentralMeridian

Gall_Stereographic
CentralMeridian

Gauss_Kruger
CentralMeridian 
ScaleFactor 
LatitudeOfOrigin

Gnomonic
LongitudeOfCenter 
LatitudeOfCenter

Hammer_Aitoff
CentralMeridian

Hotine_Oblique_Mercator_Azimuth_Center
ScaleFactor 
Azimuth 
LongitudeOfCenter 
LatitudeOfCenter

Hotine_Oblique_Mercator_Azimuth_Natural_Origin
ScaleFactor 
Azimuth 
LongitudeOfCenter 
LatitudeOfCenter

Hotine_Oblique_Mercator_Two_Point_Center
LatitudeOf1st
LatitudeOf2nd
ScaleFactor 
LongitudeOf1st
LongitudeOf2nd
LatitudeOfCenter

Hotine_Oblique_Mercator_Two_Point_Natural_Origin
LatitudeOf1st
LatitudeOf2nd
ScaleFactor 
LongitudeOf1st
LongitudeOf2nd
LatitudeOfCenter

Krovak
PseudoStandardParallel1
ScaleFactor 
Azimuth 
LongitudeOfCenter 
LatitudeOfCenter 
XScaleFactor 
YScaleFactor
Rotation

Lambert_Azimuthal_Equal_Area
CentralMeridian 
LatitudeOfOrigin

Lambert_Conformal_Conic
CentralMeridian 
StandardParallel1
StandardParallel2
ScaleFactor 
LatitudeOfOrigin

Local
ScaleFactor 
Azimuth 
LongitudeOfCenter 
LatitudeOfCenter

Loximuthal
CentralMeridian 
CentralParallel

Mercator
CentralMeridian 
StandardParallel1

Miller_Cylindrical
CentralMeridian

Mollweide
CentralMeridian

New_Zealand_Map_Grid
LongitudeOfOrigin 
LatitudeOfOrigin

Orthographic
LongitudeOfCenter 
LatitudeOfCenter

Plate_Carree
CentralMeridian

Polyconic
CentralMeridian 
LatitudeOfOrigin

Quartic_Authalic
CentralMeridian

Rectified_Skew_Orthomorphic_Center
ScaleFactor 
Azimuth 
LongitudeOfCenter 
LatitudeOfCenter 
Rotation

Rectified_Skew_Orthomorphic_Natural_Origin
ScaleFactor 
Azimuth 
LongitudeOfCenter 
LatitudeOfCenter
Rotation

Robinson
CentralMeridian

Robinson_ARC_INFO
CentralMeridian

Sinusoidal
CentralMeridian

Stereographic
CentralMeridian 
ScaleFactor 
LatitudeOfOrigin

Stereographic_North_Pole
CentralMeridian 
StandardParallel1

Stereographic_South_Pole
CentralMeridian 
StandardParallel1

Times
CentralMeridian

Transverse_Mercator
CentralMeridian 
ScaleFactor 
LatitudeOfOrigin

Transverse_Mercator_Complex
CentralMeridian 
ScaleFactor 
LatitudeOfOrigin

Two_Point_Equidistant
LatitudeOf1st 
LatitudeOf2nd
LongitudeOf1st 
LongitudeOf2nd

Van_der_Grinten_I
CentralMeridian

Vertical_Near_Side_Perspective
LongitudeOfCenter 
LatitudeOfCenter 
Height

Winkel_I
CentralMeridian 
StandardParallel1

Winkel_II
CentralMeridian 
StandardParallel1

Winkel_Tripel
CentralMeridian 
StandardParallel1