转换坐标 （.NET）

盐酸

世界坐标系：参考坐标系。所有其他坐标系都是相对于 WCS 定义的，WCS 永远不会更改。相对于 WCS 测量的值在更改其他坐标系时是稳定的。除非另有指定，否则传入和传出 .NET API 中的方法和属性的所有点都在 WCS 中表示。

UCS

用户坐标系 （UCS）：工作坐标系。用户指定 UCS 以使绘图任务更容易。传递给 AutoCAD 命令的所有点（包括从 AutoLISP 例程和外部函数返回的点）都是当前 UCS 中的点（除非用户在命令提示符下在它们前面加上 *）。如果希望应用程序将 WCS、OCS 或 DCS 中的坐标发送到 AutoCAD 命令，则必须首先通过调用转换它们，然后使用表示坐标值的方法转换 Point3d 或点 2d 对象，将它们转换为 UCS。TransformBy

法 团

对象坐标系（也称为实体坐标系或 ECS）：由 Polyline2d 和 Polyline 对象的某些方法和属性指定的点值在此坐标系中相对于对象表示。这些点通常根据对象的预期用途转换为 WCS、当前 UCS 或当前 DCS。相反，WCS、UCS 或 DCS 中的点必须先转换为 OCS，然后才能通过相同的属性写入数据库。

将坐标转换为 OCS 或从 OCS 转换坐标时，必须考虑 OCS 的法线。

DCS

显示坐标系：在显示对象之前对其进行变换的坐标系。DCS 的原点是存储在 AutoCAD 系统变量 TARGET 中的点，其Z轴是查看方向。换句话说，视口始终是其 DCS 的平面视图。这些坐标可用于确定向用户显示某些内容的位置。

私营部门发展中心

图纸空间 DCS：此坐标系只能与模型空间视口的 DCS 进行变换。这本质上是一个 2D 转换，其中X和Y坐标始终缩放。因此，它可用于查找两个坐标系之间的比例因子。PSDC 只能转换为模型空间视口。

VB.NET

Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.Geometry
 
<CommandMethod("TranslateCoordinates")> _
Public Sub TranslateCoordinates()
    '' Get the current document and database, and start a transaction
    Dim acDoc As Document = Application.DocumentManager.MdiActiveDocument
    Dim acCurDb As Database = acDoc.Database

    Using acTrans As Transaction = acCurDb.TransactionManager.StartTransaction()
        '' Open the Block table for read
        Dim acBlkTbl As BlockTable
        acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId, _
                                     OpenMode.ForRead)

        '' Open the Block table record Model space for write
        Dim acBlkTblRec As BlockTableRecord
        acBlkTblRec = acTrans.GetObject(acBlkTbl(BlockTableRecord.ModelSpace), _
                                        OpenMode.ForWrite)

        '' Create a 2D polyline with two segments (3 points)
        Dim acPoly2d As Polyline2d = New Polyline2d()

        '' Add the new object to the block table record and the transaction
        acBlkTblRec.AppendEntity(acPoly2d)
        acTrans.AddNewlyCreatedDBObject(acPoly2d, True)

        '' Before adding vertexes, the polyline must be in the drawing
        Dim acPts2dPoly As Point3dCollection = New Point3dCollection()
        acPts2dPoly.Add(New Point3d(1, 1, 0))
        acPts2dPoly.Add(New Point3d(1, 2, 0))
        acPts2dPoly.Add(New Point3d(2, 2, 0))
        acPts2dPoly.Add(New Point3d(3, 2, 0))
        acPts2dPoly.Add(New Point3d(4, 4, 0))

        For Each acPt3d As Point3d In acPts2dPoly
            Dim acVer2d As Vertex2d = New Vertex2d(acPt3d, 0, 0, 0, 0)
            acPoly2d.AppendVertex(acVer2d)
            acTrans.AddNewlyCreatedDBObject(acVer2d, True)
        Next

        '' Set the normal of the 2D polyline
        acPoly2d.Normal = New Vector3d(0, 1, 2)

        '' Get the first coordinate of the 2D polyline
        Dim acPts3d As Point3dCollection = New Point3dCollection()
        Dim acFirstVer As Vertex2d = Nothing
        For Each acObjIdVert As ObjectId In acPoly2d
            acFirstVer = acTrans.GetObject(acObjIdVert, _
                                           OpenMode.ForRead)

            acPts3d.Add(acFirstVer.Position)

            Exit For
        Next

        '' Get the first point of the polyline and 
        '' use the eleveation for the Z value
        Dim pFirstVer As Point3d = New Point3d(acFirstVer.Position.X, _
                                               acFirstVer.Position.Y, _
                                               acPoly2d.Elevation)

        '' Translate the OCS to WCS
        Dim mWPlane As Matrix3d = Matrix3d.WorldToPlane(acPoly2d.Normal)
        Dim pWCSPt As Point3d = pFirstVer.TransformBy(mWPlane)

        Application.ShowAlertDialog("The first vertex has the following " & _
                                    "coordinates:" & _
                                    vbLf & "OCS: " + pFirstVer.ToString() & _
                                    vbLf & "WCS: " + pWCSPt.ToString())

        '' Save the new objects to the database
        acTrans.Commit()
    End Using
End Sub

C#

using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.Geometry;
 
[CommandMethod("TranslateCoordinates")]
public static void TranslateCoordinates()
{
    // Get the current document and database, and start a transaction
    Document acDoc = Application.DocumentManager.MdiActiveDocument;
    Database acCurDb = acDoc.Database;

    using (Transaction acTrans = acCurDb.TransactionManager.StartTransaction())
    {
        // Open the Block table record for read
        BlockTable acBlkTbl;
        acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId,
                                     OpenMode.ForRead) as BlockTable;

        // Open the Block table record Model space for write
        BlockTableRecord acBlkTblRec;
        acBlkTblRec = acTrans.GetObject(acBlkTbl[BlockTableRecord.ModelSpace],
                                        OpenMode.ForWrite) as BlockTableRecord;

        // Create a 2D polyline with two segments (3 points)
        using (Polyline2d acPoly2d = new Polyline2d())
        {
            // Add the new object to the block table record and the transaction
            acBlkTblRec.AppendEntity(acPoly2d);
            acTrans.AddNewlyCreatedDBObject(acPoly2d, true);

            // Before adding vertexes, the polyline must be in the drawing
            Point3dCollection acPts2dPoly = new Point3dCollection();
            acPts2dPoly.Add(new Point3d(1, 1, 0));
            acPts2dPoly.Add(new Point3d(1, 2, 0));
            acPts2dPoly.Add(new Point3d(2, 2, 0));
            acPts2dPoly.Add(new Point3d(3, 2, 0));
            acPts2dPoly.Add(new Point3d(4, 4, 0));

            foreach (Point3d acPt3d in acPts2dPoly)
            {
                Vertex2d acVer2d = new Vertex2d(acPt3d, 0, 0, 0, 0);
                acPoly2d.AppendVertex(acVer2d);
                acTrans.AddNewlyCreatedDBObject(acVer2d, true);
            }

            // Set the normal of the 2D polyline
            acPoly2d.Normal = new Vector3d(0, 1, 2);

            // Get the first coordinate of the 2D polyline
            Point3dCollection acPts3d = new Point3dCollection();
            Vertex2d acFirstVer = null;

            foreach (ObjectId acObjIdVert in acPoly2d)
            {
                acFirstVer = acTrans.GetObject(acObjIdVert,
                                               OpenMode.ForRead) as Vertex2d;

                acPts3d.Add(acFirstVer.Position);

                break;
            }

            // Get the first point of the polyline and 
            // use the eleveation for the Z value
            Point3d pFirstVer = new Point3d(acFirstVer.Position.X,
                                            acFirstVer.Position.Y,
                                            acPoly2d.Elevation);

            // Translate the OCS to WCS
            Matrix3d mWPlane = Matrix3d.WorldToPlane(acPoly2d.Normal);
            Point3d pWCSPt = pFirstVer.TransformBy(mWPlane);

            Application.ShowAlertDialog("The first vertex has the following " +
                                        "coordinates:" +
                                        "\nOCS: " + pFirstVer.ToString() +
                                        "\nWCS: " + pWCSPt.ToString());
        }

        // Save the new objects to the database
        acTrans.Commit();
    }
}

VBA/ActiveX Code Reference

Sub TranslateCoordinates()
    ' Create a polyline in model space.
    Dim plineObj As AcadPolyline
    Dim points(0 To 14) As Double
 
    ' Define the 2D polyline points
    points(0) = 1: points(1) = 1: points(2) = 0
    points(3) = 1: points(4) = 2: points(5) = 0
    points(6) = 2: points(7) = 2: points(8) = 0
    points(9) = 3: points(10) = 2: points(11) = 0
    points(12) = 4: points(13) = 4: points(14) = 0
 
    ' Create a light weight Polyline object in model space
    Set plineObj = ThisDrawing.ModelSpace.AddPolyline(points)
 
    ' Find the X and Y coordinates of the
    ' first vertex of the polyline
    Dim firstVertex As Variant
    firstVertex = plineObj.Coordinate(0)
 
    ' Find the Z coordinate for the polyline
    ' using the elevation property
    firstVertex(2) = plineObj.Elevation
 
    ' Change the normal for the pline so that the
    ' difference between the coordinate systems
    ' is obvious.
    Dim plineNormal(0 To 2) As Double
    plineNormal(0) = 0#
    plineNormal(1) = 1#
    plineNormal(2) = 2#
    plineObj.Normal = plineNormal
 
    ' Translate the OCS coordinate into WCS
    Dim coordinateWCS As Variant
    coordinateWCS = ThisDrawing.Utility.TranslateCoordinates _
                        (firstVertex, acOCS, acWorld, False, plineNormal)
 
    ' Display the coordinates of the point
    MsgBox "The first vertex has the following coordinates:" _
           & vbCrLf & "OCS: (" & firstVertex(0) & "," & _
           firstVertex(1) & "," & firstVertex(2) & ")" & vbCrLf & _
           "WCS: (" & coordinateWCS(0) & "," & _
           coordinateWCS(1) & "," & coordinateWCS(2) & ")"
End Sub