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IAffineTransformation2D.DefineFromControlPoints Method (ArcObjects .NET 10.6 SDK)
ArcObjects Library Reference (Geometry)  

IAffineTransformation2D.DefineFromControlPoints Method

Defines the best affine transformation between two sets of points. Can be used to register paper maps on a digitizer.

[Visual Basic .NET]
Public Sub DefineFromControlPoints ( _
    ByVal numPoints As Integer, _
    ByRef fromPoints As IPoint, _
    ByRef toPoints As IPoint _
)

[C#]
public void DefineFromControlPoints (
    int numPoints,
    ref IPoint fromPoints,
    ref IPoint toPoints
);

[C++]
HRESULT DefineFromControlPoints(
  long numPoints,
  IPoint** fromPoints,
  IPoint** toPoints
);

[C++]

Parameters
numPoints 

  numPoints is a parameter of type long
fromPoints [in]

  fromPoints is a parameter of type IPoint**
toPoints [in]

  toPoints is a parameter of type IPoint**

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

Description

The DefineFromControlPoints method may be particularly useful if you wish to register a set of control points from a digitizer to existing known control points. This method calculates a �best fit� affine transformation to map one set of control points onto another. Please see the AffineTransformation2D coclass for a description of the mathematical model.

Errors Returned

A minimum of 3 points are needed.  If this condition is not met, the error E_GEOMETRY_INSUFFICIENT_CONTROLPOINTS is returned.

See Also

IAffineTransformation2D Interface