#include “vtkMatrix4x4.h”
#include “vtkImageReslice.h”
#include “vtkLookupTable.h”
#include “vtkImageMapToColors.h”
#include “vtkImageActor.h”
#include “vtkRenderer.h”
#include “vtkRenderWindow.h”
#include “vtkRenderWindowInteractor.h”
#include “vtkInteractorStyleImage.h”
#include “vtkCommand.h”
#include “vtkImageData.h”
// The mouse motion callback, to turn “Slicing” on and off
class vtkImageInteractionCallback : public vtkCommand
{
public:
static vtkImageInteractionCallback \*New() {
return new vtkImageInteractionCallback; };
vtkImageInteractionCallback() {
this-\>Slicing = 0;
this-\>ImageReslice = 0;
this-\>Interactor = 0; };
void SetImageReslice(vtkImageReslice \*reslice) {
this-\>ImageReslice = reslice; };
vtkImageReslice \*GetImageReslice() {
return this-\>ImageReslice; };
void SetInteractor(vtkRenderWindowInteractor \*interactor) {
this-\>Interactor = interactor; };
vtkRenderWindowInteractor \*GetInteractor() {
return this-\>Interactor; };
virtual void Execute(vtkObject \*, unsigned long event, void \*)
{
vtkRenderWindowInteractor \*interactor = this-\>GetInteractor();
```
int lastPos[2];
interactor->GetLastEventPosition(lastPos);
int currPos[2];
interactor->GetEventPosition(currPos);
if (event == vtkCommand::LeftButtonPressEvent)
{
std::cout << "left button press event" << "\n";
this->Slicing = 1;
}
else if (event == vtkCommand::LeftButtonReleaseEvent)
{
this->Slicing = 0;
}
else if (event == vtkCommand::MouseMoveEvent)
{
if (this->Slicing)
{
vtkImageReslice *reslice = this->ImageReslice;
// Increment slice position by deltaY of mouse
int deltaY = lastPos[1] - currPos[1];
std::cout << deltaY << "\n";
// reslice->GetOutput()
double sliceSpacing = reslice->GetOutput()->GetSpacing()[2];
vtkMatrix4x4 *matrix = reslice->GetResliceAxes();
// move the center point that we are slicing through
double point[4];
double center[4];
point[0] = 0.0;
point[1] = 0.0;
point[2] = sliceSpacing * deltaY;
point[3] = 1.0;
matrix->MultiplyPoint(point, center);
matrix->SetElement(0, 3, center[0]);
matrix->SetElement(1, 3, center[1]);
matrix->SetElement(2, 3, center[2]);
interactor->Render();
}
else
{
vtkInteractorStyle *style = vtkInteractorStyle::SafeDownCast(
interactor->GetInteractorStyle());
if (style)
{
style->OnMouseMove();
}
}
}
};
```
private:
// Actions (slicing only, for now)
int Slicing;
// Pointer to vtkImageReslice
vtkImageReslice \*ImageReslice;
// Pointer to the interactor
vtkRenderWindowInteractor \*Interactor;
};
// The program entry point
int main (int argc, char \*\*argv)
{
if (argc \< 2)
{
cout \<\< “Usage: " \<\< argv[0] \<\< " DATADIR/headsq/quarter” \<\< endl;
return 1;
}
// Start by loading some data.
std::string inputFilename = argv[1];
vtkSmartPointer reader =
vtkSmartPointer::New();
reader-\>SetFileName(inputFilename.c\_str());
// reader-\>SetFilePrefix(argv[1]);
reader-\>SetDataExtent(0, 256, 0, 256, 1, 94);
reader-\>SetDataSpacing(0.9375, 0.9375, 1.5);
reader-\>SetDataOrigin(0.0, 0.0, 0.0);
//reader-\>SetDataScalarTypeToUnsignedShort();
reader-\>UpdateWholeExtent();
reader-\>UpdateInformation();
// Calculate the center of the volume
// reader-\>GetOutput()-\>UpdateInformation();
int extent[6];
double spacing[3];
double origin[3];
reader-\>GetOutput()-\>GetExtent(extent);
reader-\>GetOutput()-\>GetSpacing(spacing);
reader-\>GetOutput()-\>GetOrigin(origin);
double center[3];
center[0] = origin[0] + spacing[0] \* 0.5 \* (extent[0] + extent[1]);
center[1] = origin[1] + spacing[1] \* 0.5 \* (extent[2] + extent[3]);
center[2] = origin[2] + spacing[2] \* 0.5 \* (extent[4] + extent[5]);
std::cout \<\< “Center:”;
std::cout \<\< center[0] \<\< “,” \<\< center[1] \<\< “,” \<\< center[2] \<\< “\n”;
// Matrices for axial, coronal, sagittal, oblique view orientations
static double axialElements[16] = {
1, 0, 0, 0,
0, 1, 0, 0,
0, 0, 1, 0,
0, 0, 0, 1 };
static double coronalElements[16] = {
1, 0, 0, 0,
0, 0, 1, 0,
0,-1, 0, 0,
0, 0, 0, 1 };
static double sagittalElements[16] = {
0, 0,-1, 0,
1, 0, 0, 0,
0,-1, 0, 0,
0, 0, 0, 1 };
static double obliqueElements[16] = {
1, 0, 0, 0,
0, 0.866025, -0.5, 0,
0, 0.5, 0.866025, 0,
0, 0, 0, 1 };
// Set the slice orientation
vtkMatrix4x4 \*resliceAxes = vtkMatrix4x4::New();
resliceAxes-\>DeepCopy(sagittalElements);
// Set the point through which to slice
resliceAxes-\>SetElement(0, 3, center[0]);
resliceAxes-\>SetElement(1, 3, center[1]);
resliceAxes-\>SetElement(2, 3, center[2]);
// Extract a slice in the desired orientation
vtkImageReslice \*reslice = vtkImageReslice::New();
reslice-\>SetInputConnection(reader-\>GetOutputPort());
reslice-\>SetOutputDimensionality(2);
reslice-\>SetResliceAxes(resliceAxes);
reslice-\>SetInterpolationModeToLinear();
// Create a greyscale lookup table
vtkLookupTable \*table = vtkLookupTable::New();
table-\>SetRange(0, 2000); // image intensity range
table-\>SetValueRange(0.0, 1.0); // from black to white
table-\>SetSaturationRange(0.0, 0.0); // no color saturation
table-\>SetRampToLinear();
table-\>Build();
// Map the image through the lookup table
vtkImageMapToColors \*color = vtkImageMapToColors::New();
color-\>SetLookupTable(table);
color-\>SetInputConnection(reslice-\>GetOutputPort());
// Display the image
vtkImageActor \*actor = vtkImageActor::New();
actor-\>SetInputData(color-\>GetOutput());
vtkRenderer \*renderer = vtkRenderer::New();
renderer-\>AddActor(actor);
vtkRenderWindow \*window = vtkRenderWindow::New();
window-\>AddRenderer(renderer);
// Set up the interaction
vtkInteractorStyleImage \*imageStyle = vtkInteractorStyleImage::New();
vtkRenderWindowInteractor \*interactor = vtkRenderWindowInteractor::New();
interactor-\>SetInteractorStyle(imageStyle);
window-\>SetInteractor(interactor);
window-\>Render();
vtkImageInteractionCallback \*callback = vtkImageInteractionCallback::New();
callback-\>SetImageReslice(reslice);
callback-\>SetInteractor(interactor);
imageStyle-\>AddObserver(vtkCommand::MouseMoveEvent, callback);
imageStyle-\>AddObserver(vtkCommand::LeftButtonPressEvent, callback);
imageStyle-\>AddObserver(vtkCommand::LeftButtonReleaseEvent, callback);
// Start interaction
// The Start() method doesn’t return until the window is closed by the user
interactor-\>Start();
std::cout \<\< “interactor done” \<\< “\n”;
// Clean up
callback-\>Delete();
interactor-\>Delete();
imageStyle-\>Delete();
window-\>Delete();
renderer-\>Delete();
actor-\>Delete();
reslice-\>Delete();
resliceAxes-\>Delete();
color-\>Delete();
table-\>Delete();
reader-\>Delete();
}
This displays an empty window.I am not able to find out the problem. Could someone help me with this please
-swetha
`
---
### Author:  [@dgobbi](https://discourse.vtk.org/u/dgobbi)
#### Post date: [January 23, 2019, 10:48pm UTC](https://discourse.vtk.org/t/scroll-through-2d-slices-of-3d-volume-ultrasound-mhd-file/102/2 "2019-01-23T22:48:06Z")
The official code for that program comes with the VTK source [(click here)](https://gitlab.kitware.com/vtk/vtk/blob/master/Examples/ImageProcessing/Cxx/ImageSlicing.cxx).
Probably the best way to work with the code is to start with the original “headsq” dataset (from the vtkdata package at [https://vtk.org/download/](https://vtk.org/download/)) and after you have it working with that data, you can modify it to work with your own data.
---
### Author:  [@swetha](https://discourse.vtk.org/u/swetha)
#### Post date: [February 1, 2019, 5:57am UTC](https://discourse.vtk.org/t/scroll-through-2d-slices-of-3d-volume-ultrasound-mhd-file/102/3 "2019-02-01T05:57:05Z")
Thankyou very much. it worked
---
### Author:  [@Marco\_Festugato](https://discourse.vtk.org/u/Marco_Festugato)
#### Post date: [March 15, 2019, 6:37pm UTC](https://discourse.vtk.org/t/scroll-through-2d-slices-of-3d-volume-ultrasound-mhd-file/102/4 "2019-03-15T18:37:08Z")
Hi guys, I’ve used that example to ‘cut’ my volume in the axial and sagittal plane…now i have to render both of them in the same window. I’ve managed to do it, only i can ‘scroll’ up/down through the volume just one of these planes and not both! When i scroll up/down one of my plane changes, while the other doesn’t (it’s a static image).
Do u have any suggestion/guide i could use?
Thanks in advance,
Marco