[vtkusers] vtk/Examples/Medical/Medical3.cxx, bug or not?

Mathieu Malaterre mathieu.malaterre at kitware.com
Thu Sep 14 14:45:54 EDT 2006


Hi zl2k,

	Could you submit that as a bug at:

	http://vtk.org/Bug

Thanks
Mathieu

kdsfinger at gmail.com wrote:
> hi, vtk users
> 
> The vtk/Examples/Medical/Medical3.cxx runs good as is. However, if the
> SetDisplayExtent() changes to the other values, it has great chances
> to display pure white plane with no texture written on. This result
> has been reproduced on 2 different linux machines. Is this a bug or
> not?
> 
> Attached is the copy of the Medical3.cxx. If you change
> saggital->SetDisplayExtent(32,32, 0,63, 0,92); to
> saggital->SetDisplayExtent(20,20, 0,63, 0,92);
> 
> or change
> coronal->SetDisplayExtent(0,63, 32,32, 0,92); to
> coronal->SetDisplayExtent(0,63, 20,20, 0,92);
> 
> compile and run the program again, you will see what I am saying. On
> the machine I tested, any position less than 25 will show only pure
> white plane. Please help.
> 
> zl2k
> 
> ---------------------------------------------------
> /*=========================================================================
> 
>  Program:   Visualization Toolkit
>  Module:    $RCSfile: Medical3.cxx,v $
> 
>  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
>  All rights reserved.
>  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.
> 
>     This software is distributed WITHOUT ANY WARRANTY; without even
>     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
>     PURPOSE.  See the above copyright notice for more information.
> 
> =========================================================================*/
> 
> //
> // This example reads a volume dataset, extracts two isosurfaces that
> // represent the skin and bone, creates three orthogonal planes
> // (saggital, axial, coronal), and displays them.
> //
> #include "vtkRenderer.h"
> #include "vtkRenderWindow.h"
> #include "vtkRenderWindowInteractor.h"
> #include "vtkVolume16Reader.h"
> #include "vtkPolyDataMapper.h"
> #include "vtkActor.h"
> #include "vtkOutlineFilter.h"
> #include "vtkCamera.h"
> #include "vtkStripper.h"
> #include "vtkLookupTable.h"
> #include "vtkImageDataGeometryFilter.h"
> #include "vtkProperty.h"
> #include "vtkPolyDataNormals.h"
> #include "vtkContourFilter.h"
> #include "vtkImageData.h"
> #include "vtkImageMapToColors.h"
> #include "vtkImageActor.h"
> 
> int main (int argc, char **argv)
> {
>  if (argc < 2)
>    {
>      cout << "Usage: " << argv[0] << " DATADIR/headsq/quarter" << endl;
>    return 1;
>    }
> 
>  // Create the renderer, the render window, and the interactor. The
>  // renderer draws into the render window, the interactor enables
>  // mouse- and keyboard-based interaction with the data within the
>  // render window.
>  //
>  vtkRenderer *aRenderer = vtkRenderer::New();
>  vtkRenderWindow *renWin = vtkRenderWindow::New();
>    renWin->AddRenderer(aRenderer);
>  vtkRenderWindowInteractor *iren = vtkRenderWindowInteractor::New();
>    iren->SetRenderWindow(renWin);
> 
>  // The following reader is used to read a series of 2D slices (images)
>  // that compose the volume. The slice dimensions are set, and the
>  // pixel spacing. The data Endianness must also be specified. The
>  // reader usese the FilePrefix in combination with the slice number to
>  // construct filenames using the format FilePrefix.%d. (In this case
>  // the FilePrefix is the root name of the file: quarter.)
>  vtkVolume16Reader *v16 = vtkVolume16Reader::New();
>    v16->SetDataDimensions(64,64);
>    v16->SetDataByteOrderToLittleEndian();
>    v16->SetFilePrefix (argv[1]);
>    v16->SetImageRange(1, 93);
>    v16->SetDataSpacing (3.2, 3.2, 1.5);
> 
>  // An isosurface, or contour value of 500 is known to correspond to
>  // the skin of the patient. Once generated, a vtkPolyDataNormals
>  // filter is is used to create normals for smooth surface shading
>  // during rendering.  The triangle stripper is used to create triangle
>  // strips from the isosurface; these render much faster on may
>  // systems.
>  vtkContourFilter *skinExtractor = vtkContourFilter::New();
>    skinExtractor->SetInputConnection( v16->GetOutputPort());
>    skinExtractor->SetValue(0, 500);
>  vtkPolyDataNormals *skinNormals = vtkPolyDataNormals::New();
>    skinNormals->SetInputConnection(skinExtractor->GetOutputPort());
>    skinNormals->SetFeatureAngle(60.0);
>  vtkStripper *skinStripper = vtkStripper::New();
>    skinStripper->SetInputConnection(skinNormals->GetOutputPort());
>  vtkPolyDataMapper *skinMapper = vtkPolyDataMapper::New();
>    skinMapper->SetInputConnection(skinStripper->GetOutputPort());
>    skinMapper->ScalarVisibilityOff();
>  vtkActor *skin = vtkActor::New();
>    skin->SetMapper(skinMapper);
>    skin->GetProperty()->SetDiffuseColor(1, .49, .25);
>    skin->GetProperty()->SetSpecular(.3);
>    skin->GetProperty()->SetSpecularPower(20);
> 
>  // An isosurface, or contour value of 1150 is known to correspond to
>  // the skin of the patient. Once generated, a vtkPolyDataNormals
>  // filter is is used to create normals for smooth surface shading
>  // during rendering.  The triangle stripper is used to create triangle
>  // strips from the isosurface; these render much faster on may
>  // systems.
>  vtkContourFilter *boneExtractor = vtkContourFilter::New();
>    boneExtractor->SetInputConnection(v16->GetOutputPort());
>    boneExtractor->SetValue(0, 1150);
>  vtkPolyDataNormals *boneNormals = vtkPolyDataNormals::New();
>    boneNormals->SetInputConnection(boneExtractor->GetOutputPort());
>    boneNormals->SetFeatureAngle(60.0);
>  vtkStripper *boneStripper = vtkStripper::New();
>    boneStripper->SetInputConnection(boneNormals->GetOutputPort());
>  vtkPolyDataMapper *boneMapper = vtkPolyDataMapper::New();
>    boneMapper->SetInputConnection(boneStripper->GetOutputPort());
>    boneMapper->ScalarVisibilityOff();
>  vtkActor *bone = vtkActor::New();
>    bone->SetMapper(boneMapper);
>    bone->GetProperty()->SetDiffuseColor(1, 1, .9412);
> 
>  // An outline provides context around the data.
>  //
>  vtkOutlineFilter *outlineData = vtkOutlineFilter::New();
>    outlineData->SetInputConnection(v16->GetOutputPort());
>  vtkPolyDataMapper *mapOutline = vtkPolyDataMapper::New();
>    mapOutline->SetInputConnection(outlineData->GetOutputPort());
>  vtkActor *outline = vtkActor::New();
>    outline->SetMapper(mapOutline);
>    outline->GetProperty()->SetColor(0,0,0);
> 
>  // Now we are creating three orthogonal planes passing through the
>  // volume. Each plane uses a different texture map and therefore has
>  // diferent coloration.
> 
>  // Start by creatin a black/white lookup table.
>  vtkLookupTable *bwLut = vtkLookupTable::New();
>    bwLut->SetTableRange (0, 2000);
>    bwLut->SetSaturationRange (0, 0);
>    bwLut->SetHueRange (0, 0);
>    bwLut->SetValueRange (0, 1);
>    bwLut->Build(); //effective built
> 
>  // Now create a lookup table that consists of the full hue circle
>  // (from HSV).
>  vtkLookupTable *hueLut = vtkLookupTable::New();
>    hueLut->SetTableRange (0, 2000);
>    hueLut->SetHueRange (0, 1);
>    hueLut->SetSaturationRange (1, 1);
>    hueLut->SetValueRange (1, 1);
>    hueLut->Build(); //effective built
> 
>  // Finally, create a lookup table with a single hue but having a range
>  // in the saturation of the hue.
>  vtkLookupTable *satLut = vtkLookupTable::New();
>    satLut->SetTableRange (0, 2000);
>    satLut->SetHueRange (.6, .6);
>    satLut->SetSaturationRange (0, 1);
>    satLut->SetValueRange (1, 1);
>    satLut->Build(); //effective built
> 
>  // Create the first of the three planes. The filter vtkImageMapToColors
>  // maps the data through the corresponding lookup table created above.  
> The
>  // vtkImageActor is a type of vtkProp and conveniently displays an 
> image on
>  // a single quadrilateral plane. It does this using texture mapping and as
>  // a result is quite fast. (Note: the input image has to be unsigned char
>  // values, which the vtkImageMapToColors produces.) Note also that by
>  // specifying the DisplayExtent, the pipeline requests data of this extent
>  // and the vtkImageMapToColors only processes a slice of data.
>  vtkImageMapToColors *saggitalColors = vtkImageMapToColors::New();
>    saggitalColors->SetInputConnection(v16->GetOutputPort());
>    saggitalColors->SetLookupTable(bwLut);
>  vtkImageActor *saggital = vtkImageActor::New();
>    saggital->SetInput(saggitalColors->GetOutput());
>    saggital->SetDisplayExtent(32,32, 0,63, 0,92);
> 
>  // Create the second (axial) plane of the three planes. We use the
>  // same approach as before except that the extent differs.
>  vtkImageMapToColors *axialColors = vtkImageMapToColors::New();
>    axialColors->SetInputConnection(v16->GetOutputPort());
>    axialColors->SetLookupTable(hueLut);
>  vtkImageActor *axial = vtkImageActor::New();
>    axial->SetInput(axialColors->GetOutput());
>    axial->SetDisplayExtent(0,63, 0,63, 46,46);
> 
>  // Create the third (coronal) plane of the three planes. We use
>  // the same approach as before except that the extent differs.
>  vtkImageMapToColors *coronalColors = vtkImageMapToColors::New();
>    coronalColors->SetInputConnection(v16->GetOutputPort());
>    coronalColors->SetLookupTable(satLut);
>  vtkImageActor *coronal = vtkImageActor::New();
>    coronal->SetInput(coronalColors->GetOutput());
>    coronal->SetDisplayExtent(0,63, 32,32, 0,92);
> 
>  // It is convenient to create an initial view of the data. The
>  // FocalPoint and Position form a vector direction. Later on
>  // (ResetCamera() method) this vector is used to position the camera
>  // to look at the data in this direction.
>  vtkCamera *aCamera = vtkCamera::New();
>    aCamera->SetViewUp (0, 0, -1);
>    aCamera->SetPosition (0, 1, 0);
>    aCamera->SetFocalPoint (0, 0, 0);
>    aCamera->ComputeViewPlaneNormal();
> 
>  // Actors are added to the renderer.
>  aRenderer->AddActor(outline);
>  aRenderer->AddActor(saggital);
>  aRenderer->AddActor(axial);
>  aRenderer->AddActor(coronal);
>  aRenderer->AddActor(axial);
>  aRenderer->AddActor(coronal);
>  aRenderer->AddActor(skin);
>  aRenderer->AddActor(bone);
> 
>  // Turn off bone for this example.
>  bone->VisibilityOff();
> 
>  // Set skin to semi-transparent.
>  skin->GetProperty()->SetOpacity(0.5);
> 
>  // An initial camera view is created.  The Dolly() method moves
>  // the camera towards the FocalPoint, thereby enlarging the image.
>  aRenderer->SetActiveCamera(aCamera);
>  aRenderer->Render();
>  aRenderer->ResetCamera ();
>  aCamera->Dolly(1.5);
> 
>  // Set a background color for the renderer and set the size of the
>  // render window (expressed in pixels).
>  aRenderer->SetBackground(1,1,1);
>  renWin->SetSize(640, 480);
> 
>  // Note that when camera movement occurs (as it does in the Dolly()
>  // method), the clipping planes often need adjusting. Clipping planes
>  // consist of two planes: near and far along the view direction. The
>  // near plane clips out objects in front of the plane; the far plane
>  // clips out objects behind the plane. This way only what is drawn
>  // between the planes is actually rendered.
>  aRenderer->ResetCameraClippingRange ();
> 
>  // interact with data
>  iren->Initialize();
>  iren->Start();
> 
>  // It is important to delete all objects created previously to prevent
>  // memory leaks. In this case, since the program is on its way to
>  // exiting, it is not so important. But in applications it is
>  // essential.
>  v16->Delete();
>  skinExtractor->Delete();
>  skinNormals->Delete();
>  skinStripper->Delete();
>  skinMapper->Delete();
>  skin->Delete();
>  boneExtractor->Delete();
>  boneNormals->Delete();
>  boneStripper->Delete();
>  boneMapper->Delete();
>  bone->Delete();
>  outlineData->Delete();
>  mapOutline->Delete();
>  outline->Delete();
>  bwLut->Delete();
>  hueLut->Delete();
>  satLut->Delete();
>  saggitalColors->Delete();
>  saggital->Delete();
>  axialColors->Delete();
>  axial->Delete();
>  coronalColors->Delete();
>  coronal->Delete();
>  aCamera->Delete();
>  aRenderer->Delete();
>  renWin->Delete();
>  iren->Delete();
> 
>  return 0;
> }
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