vtkMultivolume : Issue with setUserTransform() for a specific vtkVolume

[Limz90]

@Sandor

Create a dummy volume for port zero if this is the first volume. Necessary because the first transform is ignored

Hi,
Thank you for you suggestion. I created a dummy volume and added at port 0 before adding my 2 volumes.

//set up the dummy volume
		vtkSmartPointer<vtkImageData> dummyImageData = vtkSmartPointer<vtkImageData>::New();
		dummyImageData->SetDimensions(1, 1, 1);
		dummyImageData->AllocateScalars(VTK_UNSIGNED_CHAR, 1);
		dummyImageData->GetPointData()->GetScalars()->FillComponent(0, 0);

		vtkSmartPointer<vtkTrivialProducer> dummyProducer = vtkSmartPointer<vtkTrivialProducer>::New();
		dummyProducer->SetOutput(dummyImageData);

		vtkAlgorithmOutput* dummyOutputPort = dummyProducer->GetOutputPort();
		multivolumicMapper->SetInputConnection(0, dummyOutputPort);
		//multivolumicMapper->SetInputDataObject(0, dummyImageData);

		pAttributes->_multivolumeActor->SetVolume(pAttributes->_dummyVolume, 0);
		pAttributes->_dummyVolume->SetMapper(multivolumicMapper);
		pAttributes->_dummyVolume->SetVisibility(false);
		pAttributes->_multivolumeActor->Update();

And now the transformation is correctly applied.
But i have another problem with the data: the data in the two real volume are completely black, same as the dummy volume data. I dont understand why.