[vtkusers] vtkDistanceWidget and Dicom Images

[John Drescher]

On Tue, Oct 19, 2010 at 1:18 PM, Leonardo M. Ramé <l.rame at griensu.com> wrote:
> On 2010-10-19 13:09:51 -0400, John Drescher wrote:
>> On Tue, Oct 19, 2010 at 9:46 AM, Leonardo M. Ramé <l.rame at griensu.com> wrote:
>> > Hi, I use this code to add a vtkDistanceWidget to a scene showing a
>> > Dicom image:
>> >
>> > distanceWidget = vtkDistanceWidget::New();
>> > distanceWidget->SetInteractor(this->GetInteractor());
>> > static_cast<vtkDistanceRepresentation*>(distanceWidget->GetRepresentation())->SetLabelFormat("%-#6.2f mm");
>> > distanceWidget->On();
>> >
>> > The problem here is the measures I'm getting from the distance widget
>> > are not related to the real image. For example, when I measure one image
>> > with another Dicom viewer, it shows that I has 360mm width, and the
>> > vtkDistanceWidget says it has 1748,30mm.
>> >
>> > How can I define the relation between the size of the real image and the
>> > representation I'm showing on screen?
>> >
>>
>> Is the spacing correct in the vtkImageData?
>>
>> John
>
> Thanks, if I apply a spacing of 0.20, got it from dicom tag (0028,0030),
> it measures exactly as the other Dicom Viewer.
>
> ...but, now my image is rendered too small, I have to zoom it with the
> mouse. Is there a way to render it to fill the QVTKWidget regardless of
> its size?
>

I would use vtkChangeInformation filter right after the reader to
change the spacing.

John