[vtkusers] Setting vtkCamera to custom modelview & volume rendering
Aashish Chaudhary
aashish.chaudhary at kitware.com
Tue Aug 30 12:58:15 EDT 2016
Seems like a bug. Is it possible for you to send us a sample / test code?
- Aashish
On Tue, Aug 30, 2016 at 11:25 AM Bud Bundy <budric at gmail.com> wrote:
> Hi Aashish,
>
> I compiled VTK revision dbae27c5ee61cb7507d893001ae8d93a580f9e72 of the
> master branch and still the same problem with volume rendering. Rectangles
> render fine.
>
> The worldToCamera transform applied through SetModelTransformMatrix()
> seems to deform the volume for volume rendering - yet it does not deform
> the rectangle geometry. Does this behavior seem right or should I file a
> bug report? I'm a new user so it's entirely possible this is intended
> behavior, but to me at a glance and reading API documentaiton it doesn't
> seem right. Yet another screenshot attached.
>
> Thanks.
>
>
>
> On 08/29/2016 03:43 PM, Aashish Chaudhary wrote:
>
> Hi Bud,
>
> There was a bug that was fixed recently. Can you try the latest master and
> see if it is fixed? If it is, you can always cherry-pick that commit to 6.3
> branch.
>
> - Aashish
>
> On Mon, Aug 29, 2016 at 1:46 PM Bud Bundy <budric at gmail.com> wrote:
>
>> Sorry to bump my own thread but I still can't get this to work. For 2
>> identical cameras in terms of position and projection transform, after
>> adjusting the lights (or not) I get 2 different renderings.
>>
>> The only difference is I apply worldToCamera transform by setting
>> camera1->SetModelTransformMatrix(worldToCamera); whereas for camera2 I
>> transform the vtkVolume. In my understanding these should be identical in
>> terms of positioning something in camera coordinate system. But the
>> rendering is different (sample attached as volume_vtk_7.0.0.jpg).
>>
>> Weirdly enough if I render a cube instead of the volume, it works with
>> VTK 7.0.0 (attached actor_vtk_7.0.0.jpg). Same transform, both cameras
>> work. However, then same code rendering the cube doesn't work with 6.3.0
>> (attached actor_vtk_6.3.0.jpg). Not that I need to use 6.3.0. But I'm
>> just at my wits end on what to try.
>>
>> Can someone please have a look at my code and tell me how to get camera1
>> to render properly? Thank you
>>
>>
>> #include <vtkActor.h>
>> #include <vtkSmartPointer.h>
>> #include <vtkCubeSource.h>
>> #include <vtkPolyDataMapper.h>
>> #include <vtkRenderWindow.h>
>> #include <vtkRenderer.h>
>> #include <vtkRenderWindowInteractor.h>
>> #include <vtkCamera.h>
>> #include <vtkSphere.h>
>> #include <vtkSampleFunction.h>
>> #include <vtkImageShiftScale.h>
>> #include <vtkImageData.h>
>> #include <vtkPointData.h>
>> #include <vtkSmartVolumeMapper.h>
>> #include <vtkPiecewiseFunction.h>
>> #include <vtkVolumeProperty.h>
>> #include <vtkColorTransferFunction.h>
>> #include <vtkCommand.h>
>> #include <vtkMatrix4x4.h>
>>
>> #include <vtkLightCollection.h>
>> #include <vtkLight.h>
>> #include <vtkTransform.h>
>> #include <iostream>
>>
>> const double objectToWorld[16] = {
>> 0.976, 0, 0, -249.511,
>> 0, -0.976, 0, 249.224,
>> 0, 0, -2, -1251.5,
>> 0, 0, 0, 1 };
>>
>> const double worldToCamera[16] = {
>> -0.965924, 0.00168586, 0.258819, 372.757,
>> 0.258819, -0.000451724, 0.965926, 1382.12,
>> 0.00174533, 0.999998, 0, 16.3087,
>> 0, 0, 0, 1};
>>
>> vtkSmartPointer<vtkActor> generateRectangle()
>> {
>> vtkSmartPointer<vtkCubeSource> cubeSource =
>> vtkSmartPointer<vtkCubeSource>::New();
>>
>> vtkSmartPointer<vtkPolyDataMapper> mapper =
>> vtkSmartPointer<vtkPolyDataMapper>::New();
>> mapper->SetInputConnection(cubeSource->GetOutputPort());
>>
>> vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();
>> actor->SetMapper(mapper);
>> actor->SetScale(512, 512, 160);
>> actor->SetPosition(256, 256, 80);
>> vtkSmartPointer<vtkTransform> userTransform =
>> vtkSmartPointer<vtkTransform>::New();
>> userTransform->SetMatrix(objectToWorld);
>> actor->SetUserTransform(userTransform);
>> return actor;
>>
>>
>> }
>>
>> vtkSmartPointer<vtkVolume> generateVolume()
>> {
>> // Create a spherical implicit function.
>> vtkSmartPointer<vtkSphere> sphere = vtkSmartPointer<vtkSphere>::New();
>>
>> sphere->SetRadius(1);
>>
>>
>> sphere->SetCenter(0.0, 0.0, 0.0);
>>
>> vtkSmartPointer<vtkSampleFunction> sampleFunction =
>> vtkSmartPointer<vtkSampleFunction>::New();
>> sampleFunction->SetImplicitFunction(sphere);
>> sampleFunction->SetOutputScalarTypeToFloat();
>> sampleFunction->SetSampleDimensions(64, 64, 20);
>> sampleFunction->SetModelBounds(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0);
>> sampleFunction->SetCapping(false);
>> sampleFunction->SetComputeNormals(false);
>> sampleFunction->SetScalarArrayName("values");
>> sampleFunction->Update();
>>
>> vtkDataArray* a =
>> sampleFunction->GetOutput()->GetPointData()->GetScalars("values");
>> double range[2];
>> a->GetRange(range);
>>
>> vtkSmartPointer<vtkImageShiftScale> t =
>> vtkSmartPointer<vtkImageShiftScale>::New();
>> t->SetInputConnection(sampleFunction->GetOutputPort());
>>
>> t->SetShift(-range[0]);
>> double magnitude = range[1] - range[0];
>> if (magnitude == 0.0)
>> {
>> magnitude = 1.0;
>> }
>> t->SetScale(255.0 / magnitude);
>> t->SetOutputScalarTypeToUnsignedChar();
>> t->Update();
>>
>> vtkSmartPointer<vtkImageData> imageData =
>> vtkSmartPointer<vtkImageData>::New();
>> imageData->ShallowCopy(t->GetOutput());
>>
>> vtkSmartPointer<vtkSmartVolumeMapper> volumeMapper =
>> vtkSmartPointer<vtkSmartVolumeMapper>::New();
>> volumeMapper->SetBlendModeToComposite(); // composite first
>> volumeMapper->SetInputData(imageData);
>>
>> vtkSmartPointer<vtkVolumeProperty> volumeProperty =
>> vtkSmartPointer<vtkVolumeProperty>::New();
>> volumeProperty->ShadeOff();
>> volumeProperty->SetInterpolationType(VTK_LINEAR_INTERPOLATION);
>>
>> vtkSmartPointer<vtkPiecewiseFunction> compositeOpacity =
>> vtkSmartPointer<vtkPiecewiseFunction>::New();
>> compositeOpacity->AddPoint(0.0, 0.0);
>> compositeOpacity->AddPoint(80.0, 1.0);
>> compositeOpacity->AddPoint(80.1, 0.0);
>> compositeOpacity->AddPoint(255.0, 0.0);
>> volumeProperty->SetScalarOpacity(compositeOpacity); // composite
>> first.
>>
>> vtkSmartPointer<vtkColorTransferFunction> color =
>> vtkSmartPointer<vtkColorTransferFunction>::New();
>> color->AddRGBPoint(0.0, 0.0, 0.0, 1.0);
>> color->AddRGBPoint(40.0, 1.0, 0.0, 0.0);
>> color->AddRGBPoint(255.0, 1.0, 1.0, 1.0);
>> volumeProperty->SetColor(color);
>>
>> vtkSmartPointer<vtkVolume> volume = vtkSmartPointer<vtkVolume>::New();
>> volume->SetMapper(volumeMapper);
>> volume->SetProperty(volumeProperty);
>>
>> volume->SetScale(512, 512, 160);
>> volume->SetPosition(256, 256, 80);
>>
>> vtkSmartPointer<vtkTransform> userTransform =
>> vtkSmartPointer<vtkTransform>::New();
>> userTransform->SetMatrix(objectToWorld);
>> volume->SetUserTransform(userTransform);
>> return volume;
>>
>>
>> }
>>
>> void assertArrayEquals(const double * a, const double * b, size_t
>> elements)
>> {
>> for (size_t i = 0; i < elements; ++i)
>> {
>> assert(a[i] - b[i] <= std::numeric_limits<double>::epsilon());
>> }
>> }
>>
>> void assertVtkMatrixEquals(const vtkMatrix4x4 * a, const vtkMatrix4x4 * b)
>> {
>> for (size_t i = 0; i < 4; ++i)
>> {
>> for (size_t j = 0; j < 4; ++j)
>> {
>> assert(fabs(a->GetElement(i, j) - b->GetElement(i, j)) <
>> std::numeric_limits<double>::epsilon());
>>
>>
>> }
>> }
>> }
>>
>> int main()
>> {
>> // camera1
>> vtkSmartPointer<vtkCamera> camera1 =
>> vtkSmartPointer<vtkCamera>::New();
>> camera1->SetPosition(0, 0, 1000);
>> camera1->SetFocalPoint(0, 0, 0);
>>
>> camera1->SetViewUp(0, 1, 0);
>>
>>
>> camera1->SetClippingRange(0.1, 5000);
>> camera1->SetViewAngle(60);
>>
>> camera1->SetModelTransformMatrix(worldToCamera);
>>
>>
>>
>> //camera 2
>> vtkSmartPointer<vtkCamera> camera2 =
>> vtkSmartPointer<vtkCamera>::New();
>>
>> camera2->SetPosition(0, 0, 1000);
>> camera2->SetFocalPoint(0, 0, 0);
>> camera2->SetViewUp(0, 1, 0);
>> camera2->SetClippingRange(0.1, 5000);
>> camera2->SetViewAngle(60);
>>
>>
>>
>> // renderer1 using camera1
>> vtkSmartPointer<vtkRenderer> renderer1 =
>> vtkSmartPointer<vtkRenderer>::New();
>> renderer1->SetViewport(0, 0, 0.5, 1);
>>
>> renderer1->SetActiveCamera(camera1);
>> //renderer1->AddVolume(generateVolume());
>> renderer1->AddActor(generateRectangle());
>>
>>
>>
>> // renderer2 using camera2
>> vtkSmartPointer<vtkRenderer> renderer2 =
>> vtkSmartPointer<vtkRenderer>::New();
>> renderer2->SetViewport(0.5, 0, 1, 1);
>>
>> vtkSmartPointer<vtkVolume> volume2 = generateVolume();
>> vtkSmartPointer<vtkActor> rectangle2 = generateRectangle();
>> vtkSmartPointer<vtkTransform> objectToCameraTransform =
>> vtkSmartPointer<vtkTransform>::New();
>> // Generate transform (worldToCamera * objectToWorld) and apply it to
>> the model
>> objectToCameraTransform->SetMatrix(objectToWorld);
>> objectToCameraTransform->PostMultiply();
>> objectToCameraTransform->Concatenate(worldToCamera);
>> objectToCameraTransform->Update();
>> volume2->SetUserTransform(objectToCameraTransform);
>> rectangle2->SetUserTransform(objectToCameraTransform);
>> renderer2->SetActiveCamera(camera2);
>> //renderer2->AddVolume(volume2);
>> renderer2->AddActor(rectangle2);
>>
>>
>>
>> // window and interactor
>> vtkSmartPointer<vtkRenderWindow> renderWindow =
>> vtkSmartPointer<vtkRenderWindow>::New();
>> renderWindow->SetSize(1024, 512);
>> renderWindow->AddRenderer(renderer1);
>> renderWindow->AddRenderer(renderer2);
>> vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
>> vtkSmartPointer<vtkRenderWindowInteractor>::New();
>> renderWindowInteractor->SetRenderWindow(renderWindow);
>>
>> // Attempt to Adjust lights
>> renderWindow->Render();
>> vtkLight * modifiedLight = dynamic_cast<vtkLight
>> *>(renderer1->GetLights()->GetItemAsObject(0));
>> modifiedLight->SetLightTypeToHeadlight();
>> modifiedLight->SetPosition(camera1->GetPosition());
>> modifiedLight->SetFocalPoint(camera1->GetFocalPoint());
>> // Above Doesn't work, Ok let's try this as well
>> renderer1->UpdateLightsGeometryToFollowCamera();
>>
>> // Sanity check
>> assertArrayEquals(camera1->GetPosition(),
>> camera2->GetPosition(), 3);
>> assertArrayEquals(camera1->GetFocalPoint(),
>> camera2->GetFocalPoint(), 3);
>>
>> assertVtkMatrixEquals(camera1->GetProjectionTransformMatrix(renderer1),
>> camera2->GetProjectionTransformMatrix(renderer2));
>>
>>
>> vtkSmartPointer<vtkLightCollection> lightCollection1 =
>> renderer1->GetLights();
>> vtkSmartPointer<vtkLightCollection> lightCollection2 =
>> renderer2->GetLights();
>> assert(lightCollection1->GetNumberOfItems() ==
>> lightCollection2->GetNumberOfItems());
>> lightCollection1->InitTraversal();
>> lightCollection2->InitTraversal();
>> vtkSmartPointer<vtkLight> light1 = lightCollection1->GetNextItem();
>> vtkSmartPointer<vtkLight> light2 = lightCollection2->GetNextItem();
>> assertArrayEquals(light1->GetPosition(),
>> light2->GetPosition(), 3);
>> assertArrayEquals(light1->GetTransformedPosition(),
>> light2->GetTransformedPosition(), 3);
>> assertArrayEquals(light1->GetFocalPoint(),
>> light2->GetFocalPoint(), 3);
>> assertArrayEquals(light1->GetTransformedFocalPoint(),
>> light1->GetTransformedFocalPoint(), 3);
>> assertArrayEquals(light1->GetAmbientColor(),
>> light2->GetAmbientColor(), 3);
>> assertArrayEquals(light1->GetSpecularColor(),
>> light2->GetSpecularColor(), 3);
>> assertArrayEquals(light1->GetDiffuseColor(),
>> light2->GetDiffuseColor(), 3);
>>
>> renderWindow->Render();
>> renderWindowInteractor->Start();
>>
>> return EXIT_SUCCESS;
>> }
>>
>> On 08/05/2016 03:10 PM, Bud Bundy wrote:
>>
>> Thanks,
>>
>> The light positions were indeed different, but making them the same
>> didn't fix it for me. Perhaps my fix is wrong?
>>
>> void assertArrayEquals(const double * a, const double * b, size_t
>> elements)
>> {
>> for (size_t i = 0; i < elements; ++i)
>> {
>> assert(a[i] - b[i] <= std::numeric_limits<double>::epsilon());
>> }
>> }
>>
>> //previous int main() code ...
>>
>> //setting lights before first call to Render() crashes program, also
>> describedh http://www.vtk.org/Wiki/VTK/Examples/Cxx/Lighting/Light
>>
>> renderWindow->Render();
>>
>> renderer2->RemoveAllLights();
>> vtkSmartPointer<vtkLight> newLight = vtkSmartPointer<vtkLight>::New();
>> newLight->SetPosition(0, 0, 1000);
>> renderer2->AddLight(newLight);
>>
>> //assert lighting is the same
>> vtkSmartPointer<vtkLightCollection> lightCollection1 =
>> renderer1->GetLights();
>> vtkSmartPointer<vtkLightCollection> lightCollection2 =
>> renderer2->GetLights();
>> assert(lightCollection1->GetNumberOfItems() ==
>> lightCollection2->GetNumberOfItems());
>> lightCollection1->InitTraversal();
>> lightCollection2->InitTraversal();
>> vtkSmartPointer<vtkLight> light1 = lightCollection1->GetNextItem();
>> vtkSmartPointer<vtkLight> light2 = lightCollection2->GetNextItem();
>> assertArrayEquals(light1->GetPosition(), light2->GetPosition(), 3);
>> assertArrayEquals(light1->GetTransformedPosition(),
>> light2->GetTransformedPosition(), 3);
>> assertArrayEquals(light1->GetFocalPoint(), light2->GetFocalPoint(),
>> 3);
>> assertArrayEquals(light1->GetTransformedFocalPoint(),
>> light1->GetTransformedFocalPoint(), 3);
>> assertArrayEquals(light1->GetAmbientColor(),
>> light2->GetAmbientColor(), 3);
>> assertArrayEquals(light1->GetSpecularColor(),
>> light2->GetSpecularColor(), 3);
>> assertArrayEquals(light1->GetDiffuseColor(),
>> light2->GetDiffuseColor(), 3);
>>
>> renderWindow->Render();
>>
>> renderWindowInteractor->Start();
>>
>>
>> On 08/05/16 14:10, David E DeMarle wrote:
>>
>> I was just doing a very similar thing and noticed that light positions
>> are only updated with the set origin, focal point and up. I ended up
>> computing those for my intended matrix and lighting then worked as
>> expected.
>>
>> On Aug 5, 2016 1:12 PM, "Bud Bundy" <budric at gmail.com> wrote:
>>
>>> Hi,
>>>
>>> I need to setup the camera to an arbitrary modelview matrix I have in
>>> memory. I managed to get some code working such that
>>> GetModelViewTransformMatrix() returns the modelview I have/want. However
>>> the volume rendering is sometimes blank, and I don't understand why because
>>> the volume is in front of the camera. I managed to boil down the problem
>>> to the following code below. camera1 and camera2 have the same modelview
>>> transform, however the rendering look very different (I've attached a
>>> screen shot) - though not blank it's a lot dimmer.
>>>
>>> The code is loosely based on:
>>> http://www.vtk.org/Wiki/VTK/Examples/Cxx/VolumeRendering/SmartVolumeMapper
>>>
>>> I'm using VTK 7.0
>>>
>>> #include <vtkActor.h>
>>> #include <vtkSmartPointer.h>
>>> #include <vtkCubeSource.h>
>>> #include <vtkPolyDataMapper.h>
>>> #include <vtkRenderWindow.h>
>>> #include <vtkRenderer.h>
>>> #include <vtkRenderWindowInteractor.h>
>>> #include <vtkCamera.h>
>>> #include <vtkSphere.h>
>>> #include <vtkSampleFunction.h>
>>> #include <vtkImageShiftScale.h>
>>> #include <vtkImageData.h>
>>> #include <vtkPointData.h>
>>> #include <vtkSmartVolumeMapper.h>
>>> #include <vtkPiecewiseFunction.h>
>>> #include <vtkVolumeProperty.h>
>>> #include <vtkColorTransferFunction.h>
>>> #include <vtkCommand.h>
>>> #include <vtkMatrix4x4.h>
>>>
>>> vtkSmartPointer<vtkVolume> generateVolume()
>>> {
>>> // Create a spherical implicit function.
>>> vtkSmartPointer<vtkSphere> sphere =
>>> vtkSmartPointer<vtkSphere>::New();
>>> sphere->SetRadius(0.1);
>>> sphere->SetCenter(0.0, 0.0, 0.0);
>>>
>>> vtkSmartPointer<vtkSampleFunction> sampleFunction =
>>> vtkSmartPointer<vtkSampleFunction>::New();
>>> sampleFunction->SetImplicitFunction(sphere);
>>> sampleFunction->SetOutputScalarTypeToFloat();
>>> sampleFunction->SetSampleDimensions(64, 64, 20);
>>> sampleFunction->SetModelBounds(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0);
>>> sampleFunction->SetCapping(false);
>>> sampleFunction->SetComputeNormals(false);
>>> sampleFunction->SetScalarArrayName("values");
>>> sampleFunction->Update();
>>>
>>> vtkDataArray* a =
>>> sampleFunction->GetOutput()->GetPointData()->GetScalars("values");
>>> double range[2];
>>> a->GetRange(range);
>>>
>>> vtkSmartPointer<vtkImageShiftScale> t =
>>> vtkSmartPointer<vtkImageShiftScale>::New();
>>> t->SetInputConnection(sampleFunction->GetOutputPort());
>>>
>>> t->SetShift(-range[0]);
>>> double magnitude = range[1] - range[0];
>>> if (magnitude == 0.0)
>>> {
>>> magnitude = 1.0;
>>> }
>>> t->SetScale(255.0 / magnitude);
>>> t->SetOutputScalarTypeToUnsignedChar();
>>> t->Update();
>>>
>>> vtkSmartPointer<vtkImageData> imageData =
>>> vtkSmartPointer<vtkImageData>::New();
>>> imageData->ShallowCopy(t->GetOutput());
>>>
>>> vtkSmartPointer<vtkSmartVolumeMapper> volumeMapper =
>>> vtkSmartPointer<vtkSmartVolumeMapper>::New();
>>> volumeMapper->SetBlendModeToComposite(); // composite first
>>> volumeMapper->SetInputData(imageData);
>>>
>>> vtkSmartPointer<vtkVolumeProperty> volumeProperty =
>>> vtkSmartPointer<vtkVolumeProperty>::New();
>>> volumeProperty->ShadeOff();
>>> volumeProperty->SetInterpolationType(VTK_LINEAR_INTERPOLATION);
>>>
>>> vtkSmartPointer<vtkPiecewiseFunction> compositeOpacity =
>>> vtkSmartPointer<vtkPiecewiseFunction>::New();
>>> compositeOpacity->AddPoint(0.0, 0.0);
>>> compositeOpacity->AddPoint(80.0, 1.0);
>>> compositeOpacity->AddPoint(80.1, 0.0);
>>> compositeOpacity->AddPoint(255.0, 0.0);
>>> volumeProperty->SetScalarOpacity(compositeOpacity); // composite
>>> first.
>>>
>>> vtkSmartPointer<vtkColorTransferFunction> color =
>>> vtkSmartPointer<vtkColorTransferFunction>::New();
>>> color->AddRGBPoint(0.0, 0.0, 0.0, 1.0);
>>> color->AddRGBPoint(40.0, 1.0, 0.0, 0.0);
>>> color->AddRGBPoint(255.0, 1.0, 1.0, 1.0);
>>> volumeProperty->SetColor(color);
>>>
>>> vtkSmartPointer<vtkVolume> volume =
>>> vtkSmartPointer<vtkVolume>::New();
>>> volume->SetMapper(volumeMapper);
>>> volume->SetProperty(volumeProperty);
>>>
>>> vtkSmartPointer<vtkMatrix4x4> volumeScaleTransform =
>>> vtkSmartPointer<vtkMatrix4x4>::New();
>>> volumeScaleTransform->Identity();
>>> volumeScaleTransform->SetElement(0, 0, 512);
>>> volumeScaleTransform->SetElement(1, 1, 512);
>>> volumeScaleTransform->SetElement(2, 2, 160);
>>> volume->SetUserMatrix(volumeScaleTransform);
>>> return volume;
>>> }
>>>
>>> int main()
>>> {
>>> // camera1
>>> vtkSmartPointer<vtkCamera> camera1 =
>>> vtkSmartPointer<vtkCamera>::New();
>>> camera1->SetPosition(0, 0, 1000);
>>> camera1->SetFocalPoint(0, 0, 0);
>>> camera1->SetClippingRange(0.1, 5000);
>>> camera1->SetViewAngle(60);
>>>
>>> //camera 2
>>> vtkSmartPointer<vtkCamera> camera2 =
>>> vtkSmartPointer<vtkCamera>::New();
>>> camera2->SetPosition(0, 0, 0); //I do not want any
>>> additional translation that comes with default (0,0,1) setting.
>>> camera2->SetFocalPoint(0, 0, -1); //setting this to (0,0,0)
>>> causes whole modelview matrix to be 0, regardless of what
>>> SetModelTransformMatrix() sets
>>> camera2->SetViewAngle(60);
>>> camera2->SetClippingRange(0.1, 5000);
>>> double modelViewTransform[16] = { 1, 0, 0, 0,
>>> 0, 1, 0, 0,
>>> 0, 0, 1, -1000,
>>> 0, 0, 0, 1 };
>>> camera2->SetModelTransformMatrix(modelViewTransform);
>>>
>>> // renderer1 using camera1
>>> vtkSmartPointer<vtkRenderer> renderer1 =
>>> vtkSmartPointer<vtkRenderer>::New();
>>> renderer1->SetViewport(0, 0, 0.5, 1);
>>> renderer1->AddVolume(generateVolume());
>>> renderer1->SetActiveCamera(camera1);
>>>
>>> // renderer2 using camera2
>>> vtkSmartPointer<vtkRenderer> renderer2 =
>>> vtkSmartPointer<vtkRenderer>::New();
>>> renderer2->SetViewport(0.5, 0, 1, 1);
>>> renderer2->AddVolume(generateVolume());
>>> renderer2->SetActiveCamera(camera2);
>>>
>>> // assert model view matrices are the same
>>> vtkSmartPointer<vtkMatrix4x4> vtkModelViewMatrix1 =
>>> renderer1->GetActiveCamera()->GetModelViewTransformMatrix();
>>> vtkSmartPointer<vtkMatrix4x4> vtkModelViewMatrix2 =
>>> renderer2->GetActiveCamera()->GetModelViewTransformMatrix();
>>> for (int i = 0; i < 4; ++i)
>>> for (int j = 0; j < 4; ++j)
>>> assert(vtkModelViewMatrix1->GetElement(i, j) ==
>>> vtkModelViewMatrix2->GetElement(i, j));
>>>
>>> // window and interactor
>>> vtkSmartPointer<vtkRenderWindow> renderWindow =
>>> vtkSmartPointer<vtkRenderWindow>::New();
>>> renderWindow->SetSize(1024, 512);
>>> renderWindow->AddRenderer(renderer1);
>>> renderWindow->AddRenderer(renderer2);
>>> vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
>>> vtkSmartPointer<vtkRenderWindowInteractor>::New();
>>> renderWindowInteractor->SetRenderWindow(renderWindow);
>>>
>>> renderWindow->Render();
>>> renderWindowInteractor->Start();
>>>
>>> return EXIT_SUCCESS;
>>> }
>>>
>>>
>>> Thank you very much.
>>>
>>>
>>> _______________________________________________
>>> Powered by www.kitware.com
>>>
>>> Visit other Kitware open-source projects at
>>> http://www.kitware.com/opensource/opensource.html
>>>
>>> Please keep messages on-topic and check the VTK FAQ at:
>>> http://www.vtk.org/Wiki/VTK_FAQ
>>>
>>> Search the list archives at: http://markmail.org/search/?q=vtkusers
>>>
>>> Follow this link to subscribe/unsubscribe:
>>> http://public.kitware.com/mailman/listinfo/vtkusers
>>>
>>>
>>
>> _______________________________________________
>> Powered by www.kitware.com
>>
>> Visit other Kitware open-source projects at
>> http://www.kitware.com/opensource/opensource.html
>>
>> Please keep messages on-topic and check the VTK FAQ at:
>> http://www.vtk.org/Wiki/VTK_FAQ
>>
>> Search the list archives at: http://markmail.org/search/?q=vtkusers
>>
>> Follow this link to subscribe/unsubscribe:
>> http://public.kitware.com/mailman/listinfo/vtkusers
>>
>
> _______________________________________________
> Powered by www.kitware.com
>
> Visit other Kitware open-source projects at
> http://www.kitware.com/opensource/opensource.html
>
> Please keep messages on-topic and check the VTK FAQ at:
> http://www.vtk.org/Wiki/VTK_FAQ
>
> Search the list archives at: http://markmail.org/search/?q=vtkusers
>
> Follow this link to subscribe/unsubscribe:
> http://public.kitware.com/mailman/listinfo/vtkusers
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/vtkusers/attachments/20160830/e203db1f/attachment.html>
More information about the vtkusers
mailing list