Raster Images belong to the category of entities that support being scaled non-uniformly.
The entities that support non-uniform scaling are:
AcDbLeader, AcDbMLine, AcDbMText, AcDbOle2Frame, AcDbPloyFaceMesh, AcDbPolygonMesh, AcDbRay, AcDbXline, AcDbFcf, AcDbSolid, AcDbEllipse, AcDbSpline, AcDbImage.
The API doesn’t provide a built-in functionality in order to create a non-uniform scaling matrix. You would need to create such a matrix by filling up the coefficient yourself. Building a scaling matrix is quite straightforward as it is a diagonal matrix that contains the scale coefficients corresponding respectively to x, y and z directions.
The C# command below illustrates how to scale non-uniformly a raster image so it will fit a given rectangle (Width x Height):
[CommandMethod("Scale2Fit")]
public void Scale2Fit()
{
Document doc = Application.DocumentManager.MdiActiveDocument;
Database db = doc.Database;
Editor ed = doc.Editor;
PromptEntityOptions peo = new PromptEntityOptions(
"\nSelect image: ");
peo.SetRejectMessage("\nInvalid selection…");
peo.AddAllowedClass(typeof(RasterImage), false);
PromptEntityResult per = ed.GetEntity(peo);
if (p
er.Status != PromptStatus.OK)
return;
double width = 50;
double height = 30;
using (Transaction Tx =
db.TransactionManager.StartTransaction())
{
RasterImage image = Tx.GetObject(
per.ObjectId,
OpenMode.ForWrite)
as RasterImage;
Point3d origin = image.Orientation.Origin;
double scaleX = width / image.Width;
double scaleY = height / image.Height;
double[] coe
ffs = new double[]
{
scaleX, 0, 0, 0,
0, scaleY, 0, 0,
0, 0, 1, 0,
0, 0, 0, 1
};
Matrix3d matrix = new Matrix3d(coeffs);
image.TransformBy(matrix);
//Reset original position
image.Orientation = new CoordinateSystem3d(
origin,
image.Orientation.Xaxis,
image.Orientation.Yaxis);
Tx.Commit();
}
}
<
p style=”line-height: normal;margin: 0in 0in 0pt” class=”MsoNormal”>
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