ImageWarp
Repository source: ImageWarp
Description¶
Combining the imaging and visualization pipelines to deform an image in the z-direction. The vtkMergeFilter is used to combine the warped surface with the original color data.
Info
See Figure 10-17 in Chapter 10 the VTK Textbook.
Other languages
See (Python), (PythonicAPI)
Question
If you have a question about this example, please use the VTK Discourse Forum
Code¶
ImageWarp.cxx
/*
* This example shows how to combine data from both the imaging
* and graphics pipelines. The vtkMergeData filter is used to
* merge the data from each together.
*/
#include <vtkActor.h>
#include <vtkBMPReader.h>
#include <vtkCamera.h>
#include <vtkDataSetMapper.h>
#include <vtkImageDataGeometryFilter.h>
#include <vtkImageLuminance.h>
#include <vtkMergeFilter.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkWarpScalar.h>
#include <array>
#include <iomanip>
#include <iostream>
#include <string>
int main(int argc, char* argv[])
{
vtkNew<vtkNamedColors> colors;
if (argc < 2)
{
std::cout << "Usage: " << argv[0] << " fileName" << std::endl;
std::cout << "where: fileName is the masonry.bmp file." << std::endl;
return EXIT_FAILURE;
}
std::string fileName = argv[1];
// Set the background color.
std::array<unsigned char, 4> bkg{{60, 93, 144, 255}};
colors->SetColor("BkgColor", bkg.data());
// Read in an image and compute a luminance value-> The image is extracted
// as a set of polygons (vtkImageDataGeometryFilter). We then will
// warp the plane using the scalar (luminance) values.
//
vtkNew<vtkBMPReader> reader;
reader->SetFileName(fileName.c_str());
// Convert the image to a grey scale.
vtkNew<vtkImageLuminance> luminance;
luminance->SetInputConnection(reader->GetOutputPort());
// Pass the data to the pipeline as polygons.
vtkNew<vtkImageDataGeometryFilter> geometry;
geometry->SetInputConnection(luminance->GetOutputPort());
// Warp the data in a direction perpendicular to the image plane.
vtkNew<vtkWarpScalar> warp;
warp->SetInputConnection(geometry->GetOutputPort());
warp->SetScaleFactor(-0.1);
// Use vtkMergeFilter to combine the original image with the warped geometry.
vtkNew<vtkMergeFilter> merge;
merge->SetGeometryConnection(warp->GetOutputPort());
merge->SetScalarsConnection(reader->GetOutputPort());
vtkNew<vtkDataSetMapper> mapper;
mapper->SetInputConnection(merge->GetOutputPort());
mapper->SetScalarRange(0, 255);
vtkNew<vtkActor> actor;
actor->SetMapper(mapper);
// Create the rendering window, renderer, and interactive renderer.
//
vtkNew<vtkRenderer> ren;
vtkNew<vtkRenderWindow> renWin;
renWin->AddRenderer(ren);
vtkNew<vtkRenderWindowInteractor> iren;
iren->SetRenderWindow(renWin);
// Add the actors to the renderer, set the background and size.
ren->AddActor(actor);
ren->ResetCamera();
ren->SetBackground(colors->GetColor3d("BkgColor").GetData());
// ren->GetActiveCamera()->Azimuth(20);
// ren->GetActiveCamera()->Elevation(30);
// ren->ResetCameraClippingRange();
// ren->GetActiveCamera()->Zoom(1.3);
ren->GetActiveCamera()->SetPosition(-100, -130, 325);
ren->GetActiveCamera()->SetFocalPoint(105, 114, -29);
ren->GetActiveCamera()->SetViewUp(0.51, 0.54, 0.67);
ren->ResetCameraClippingRange();
renWin->SetSize(512, 512);
renWin->SetWindowName("ImageWarp");
// Render the image.
renWin->Render();
iren->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
project(ImageWarp)
find_package(VTK COMPONENTS
CommonColor
CommonCore
FiltersCore
FiltersGeneral
FiltersGeometry
IOImage
ImagingColor
InteractionStyle
RenderingContextOpenGL2
RenderingCore
RenderingFreeType
RenderingGL2PSOpenGL2
RenderingOpenGL2
)
if (NOT VTK_FOUND)
message(FATAL_ERROR "ImageWarp: Unable to find the VTK build folder.")
endif()
# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
add_executable(ImageWarp MACOSX_BUNDLE ImageWarp.cxx )
target_link_libraries(ImageWarp PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS ImageWarp
MODULES ${VTK_LIBRARIES}
)
Download and Build ImageWarp¶
Click here to download ImageWarp and its CMakeLists.txt file. Once the tarball ImageWarp.tar has been downloaded and extracted,
cd ImageWarp/build
If VTK is installed:
cmake ..
If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:
cmake -DVTK_DIR:PATH=/home/me/vtk_build ..
Build the project:
make
and run it:
./ImageWarp
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.