MultiVolumeRenderWindow - prototypical test of multi volume handling with VTK

MultiVolumeRenderWindow.cpp

// Created by: A. Ophagen
// Created on: 2018-10-25

#define RENDERPIPELINEOUTPUT 0

#include "MultiVolumeRenderWindow.h"

#include <vtkNew.h>
#include <vtkImageData.h>
#include <vtkTrivialProducer.h>
#include <vtkColorTransferFunction.h>
#include <vtkPiecewiseFunction.h>
#include <vtkVolume.h>
#include <vtkVolumeProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkInteractorStyleTrackballCamera.h>
#include <vtkCamera.h>
#include <vtkMultiVolume.h>
#include <vtkOpenGLGPUVolumeRayCastMapper.h>

int main(int , char *[])
{
    // Multi volume instance
    // ---------------------
    vtkNew<vtkMultiVolume> overlappingVol;
    vtkNew<vtkOpenGLGPUVolumeRayCastMapper> mapper;
    mapper->SetUseJittering(0);
    overlappingVol->SetMapper(mapper);

    // Create data
    std::vector< vtkSmartPointer< vtkTrivialProducer > > producers{};
    std::vector< vtkSmartPointer< vtkColorTransferFunction > > ctfs{};
    std::vector< vtkSmartPointer< vtkPiecewiseFunction > > sofs{};
    std::vector< vtkSmartPointer< vtkPiecewiseFunction > > gofs{};
    std::vector< vtkSmartPointer< vtkVolume > > volumes{};

    // Volume 0 (value 0 - -127, size 128 x 128 x 128)
    // ---------------------------

    int index = static_cast< int >( producers.size() );

    producers.emplace_back( vtkSmartPointer< vtkTrivialProducer >::New() );
    producers.back()->SetOutput( createVtkImage( true, 128, 128, 128 ) );
    producers.back()->Update();

    ctfs.emplace_back( vtkSmartPointer<vtkColorTransferFunction>::New() );
    ctfs.back()->AddRGBPoint( -127, 0.0, 0.0, 0.0 );
    ctfs.back()->AddRGBPoint(  -63, 1.0, 0.5, 0.3 );
    ctfs.back()->AddRGBPoint(    0, 1.0, 1.0, 0.9 );
    ctfs.back()->SetColorSpaceToHSV();

    sofs.emplace_back( vtkSmartPointer<vtkPiecewiseFunction>::New() );
    sofs.back()->AddPoint( -127, 0.0 );
    sofs.back()->AddPoint(    0, 1.0 );

//    gofs.emplace_back( vtkSmartPointer<vtkPiecewiseFunction>::New() );
//    gofs.back()->AddPoint(   0, 1.0 );
//    gofs.back()->AddPoint( 100, 1.0 );

    volumes.emplace_back( vtkSmartPointer<vtkVolume>::New() );
    volumes.back()->GetProperty()->SetColor(ctfs.back());
    volumes.back()->GetProperty()->SetScalarOpacity(sofs.back());
//    volumes.back()->GetProperty()->SetGradientOpacity(gofs.back());
    volumes.back()->GetProperty()->SetInterpolationType(VTK_LINEAR_INTERPOLATION);

    // use data for volume 0
    mapper->SetInputConnection( index, producers.back()->GetOutputPort());
    overlappingVol->SetVolume( volumes.back(), index );

    // Volume 1 (value 0 - 63, size 64 x 64 x 64)
    // ---------------------------
    index = static_cast< int >( producers.size() );

    producers.emplace_back( vtkSmartPointer< vtkTrivialProducer >::New() );
    producers.back()->SetOutput( createVtkImage( false, 64, 64, 64 ) );
    producers.back()->Update();

    ctfs.emplace_back( vtkSmartPointer<vtkColorTransferFunction>::New() );
    ctfs.back()->AddRGBPoint(  0, 0.0, 0.0, 0.0 );
    ctfs.back()->AddRGBPoint( 15, 0.5, 1.0, 0.3 );
    ctfs.back()->AddRGBPoint( 47, 0.5, 1.0, 0.3 );
    ctfs.back()->AddRGBPoint( 63, 1.0, 1.0, 0.9 );
    ctfs.back()->SetColorSpaceToHSV();

    sofs.emplace_back( vtkSmartPointer<vtkPiecewiseFunction>::New() );
    sofs.back()->AddPoint(  0, 0.0 );
    sofs.back()->AddPoint( 63, 1.0 );

//    gofs.emplace_back( vtkSmartPointer<vtkPiecewiseFunction>::New() );
//    gofs.back()->AddPoint(   0, 1.0 );
//    gofs.back()->AddPoint( 100, 1.0 );

    volumes.emplace_back( vtkSmartPointer<vtkVolume>::New() );
    volumes.back()->GetProperty()->SetColor(ctfs.back());
    volumes.back()->GetProperty()->SetScalarOpacity(sofs.back());
//    volumes.back()->GetProperty()->SetGradientOpacity(gofs.back());
    volumes.back()->GetProperty()->SetInterpolationType(VTK_LINEAR_INTERPOLATION);

    volumes.back()->RotateX( -55. );
    volumes.back()->SetPosition( 80., 50., 130. );

    // use data for volume 1
    mapper->SetInputConnection( index, producers.back()->GetOutputPort());
    overlappingVol->SetVolume( volumes.back(), index );

    // Volume 2 (value 0 - 127, size 64 x 128 x 64)
    // -----------------------------
    index = static_cast< int >( producers.size() );

    producers.emplace_back( vtkSmartPointer< vtkTrivialProducer >::New() );
    producers.back()->SetOutput( createVtkImage( false, 64, 128, 64 ) );
    producers.back()->Update();

    ctfs.emplace_back( vtkSmartPointer<vtkColorTransferFunction>::New() );
    ctfs.back()->AddRGBPoint(   0, 1.0, 0.3, 0.2 );
    ctfs.back()->AddRGBPoint(  64, 0.3, 0.2, 0.9 );
    ctfs.back()->AddRGBPoint( 127, 0.5, 0.6, 1.0 );

    sofs.emplace_back( vtkSmartPointer<vtkPiecewiseFunction>::New() );
    sofs.back()->AddPoint(   0,  0.3 );
    sofs.back()->AddPoint( 127,  0.8 );

//    gofs.emplace_back( vtkSmartPointer<vtkPiecewiseFunction>::New() );
//    gofs.back()->AddPoint(   0, 1.0 );
//    gofs.back()->AddPoint( 100, 1.0 );

    volumes.emplace_back( vtkSmartPointer<vtkVolume>::New() );
    volumes.back()->GetProperty()->SetColor( ctfs.back() );
    volumes.back()->GetProperty()->SetScalarOpacity( sofs.back() );
//    volumes.back()->GetProperty()->SetGradientOpacity( gofs.back() );
    volumes.back()->GetProperty()->SetInterpolationType( VTK_LINEAR_INTERPOLATION );

    volumes.back()->SetPosition( 210., 200., -90. );
    volumes.back()->RotateX(  90. );
    volumes.back()->RotateY( -95. );
    volumes.back()->RotateZ(  -5. );

    // use data for volume 2
    mapper->SetInputConnection( index, producers.back()->GetOutputPort() );
    overlappingVol->SetVolume( volumes.back(), index );

    // Rendering context
    vtkNew<vtkRenderWindow> renWin;
    renWin->SetSize( 512, 512 );
    renWin->SetMultiSamples( 0 );

    vtkNew<vtkRenderer> ren;
    renWin->AddRenderer( ren );
    ren->SetBackground( 0.0, 0.0, 0.0 );

    vtkNew<vtkRenderWindowInteractor> iren;
    iren->SetRenderWindow( renWin );

#if RENDERPIPELINEOUTPUT
    std::cout << "RENDERER " << std::endl;
    std::cout << "======== " << std::endl;
    ren->PrintSelf( std::cout, vtkIndent() );
    std::cout << "MAPPER " << std::endl;
    std::cout << "====== " << std::endl;
    mapper->PrintSelf( std::cout, vtkIndent() );
    std::cout << "MULTI VOLUME " << std::endl;
    std::cout << "============ " << std::endl;
    overlappingVol->PrintSelf( std::cout, vtkIndent() );
    for( size_t i = 0; i < volumes.size(); ++i )
    {
        std::cout << "VOLUME " << i << std::endl;
        std::cout << "========" << std::endl;
        volumes.at( i )->PrintSelf( std::cout, vtkIndent() );
        vtkImageData* image = vtkImageData::SafeDownCast( producers.at( i )->GetOutputDataObject( 0 ) );
        if(image)
        {
            std::cout << "IMAGE DATA " << i << std::endl;
            std::cout << "============" << std::endl;
            image->PrintSelf( std::cout, vtkIndent(2) );
        }
        std::cout << "VOLUME PROPERTIES " << i << std::endl;
        std::cout << "===================" << std::endl;
        volumes.at( i )->GetProperty()->PrintSelf( std::cout, vtkIndent(2) );
        std::cout << "-> COLOR TRANSFER FUNCTION " << i << std::endl;
        std::cout << "   =========================" << std::endl;
        volumes.at( i )->GetProperty()->GetRGBTransferFunction()->PrintSelf( std::cout, vtkIndent(3) );
        std::cout << "-> SCALAR OPACITY " << i << std::endl;
        std::cout << "   ================" << std::endl;
        volumes.at( i )->GetProperty()->GetScalarOpacity()->PrintSelf( std::cout, vtkIndent(3) );
        std::cout << "-> GRADIENT OPACITY " << i << std::endl;
        std::cout << "   ==================" << std::endl;
        volumes.at( i )->GetProperty()->GetGradientOpacity()->PrintSelf( std::cout, vtkIndent(3) );
    }
#endif

    ren->AddVolume(overlappingVol);
    renWin->Render();

    iren->Start();
}

vtkSmartPointer<vtkImageData> createVtkImage(bool invert , int x, int y, int z)
{
    // Create an image data
    vtkSmartPointer<vtkImageData> imageData = vtkSmartPointer<vtkImageData>::New();

    // Specify the size of the image data
    imageData->SetDimensions( x, y, z);
    imageData->AllocateScalars(VTK_DOUBLE,1);

    int* dims = imageData->GetDimensions();

    // Fill every entry of the image data with "2.0"
    for (int slice = 0; slice < dims[2]; slice++)
    {
        for (int row = 0; row < dims[1]; row++)
        {
            for (int voxel = 0; voxel < dims[0]; voxel++)
            {
                double value = invert ? -slice : slice;
                double* pixel = static_cast<double*>( imageData->GetScalarPointer(
                                                          voxel, row, slice ) );
                pixel[0] = value;
            }
        }
    }
    return imageData;
}

MultiVolumeRenderWindow.h

// Created by: Angelika Ophagen
// Created on: 2018-10-25

#include <vtkSmartPointer.h>
class vtkImageData;

vtkSmartPointer<vtkImageData> createVtkImage(bool invert, int x = 3, int y = 3, int z = 3 );