[vtkusers] Display Coordinates Error

[Wenlong Wang]

Dear all,

Here is a function I write, it calculates the display coordinates of a
point set. This function is called after I transform a point set and I pass
the pointer of the point set to this function.

*void Dist_2DLandmarks(vtkPoints* transformed_points)
{
    double p_trans[3];
    vtkPolyData* polydata = vtkPolyData::New();
    vtkPolyDataMapper* mapper = vtkPolyDataMapper::New();
    vtkActor* actor = vtkActor::New();

    polydata->SetPoints(transformed_points);
    polydata->SetPolys(poly);
    polydata->GetPointData()->SetScalars(scalars);
    mapper->SetInput(polydata);
    actor->SetMapper(mapper);
    ren->AddActor(actor);

    for (int index = 0; index<sizeof(landmarks)/sizeof(int); index++)
    {
        transformed_points->GetPoint(landmarks[index], p_trans);
        ren->SetWorldPoint(p_trans);
        ren->WorldToDisplay();
        ren->GetDisplayPoint(p_trans);
    }

    return;
}*

What I do before call this function is Scale (0.72, 0.72, 0.72) and Rotate
(2.5). The result shows the display coordinates has changed a lot, from
(170, 254, 0.4) to (2362, 64, 1.7).

I don't know what is wrong with it. Can anyone give me some advice? Or
write me a demo code would carry out the work?

Thank you very much.

Best wishes
Long
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