LinePlot
Description¶
This example demonstrates how to plot XY data.
Question
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Code¶
LinePlot.cxx
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderWindow.h>
#include <vtkSmartPointer.h>
#include <vtkChartXY.h>
#include <vtkTable.h>
#include <vtkPlot.h>
#include <vtkFloatArray.h>
#include <vtkContextView.h>
#include <vtkContextScene.h>
#include <vtkPen.h>
int main(int, char *[])
{
// Create a table with some points in it
vtkSmartPointer<vtkTable> table =
vtkSmartPointer<vtkTable>::New();
vtkSmartPointer<vtkFloatArray> arrX =
vtkSmartPointer<vtkFloatArray>::New();
arrX->SetName("X Axis");
table->AddColumn(arrX);
vtkSmartPointer<vtkFloatArray> arrC =
vtkSmartPointer<vtkFloatArray>::New();
arrC->SetName("Cosine");
table->AddColumn(arrC);
vtkSmartPointer<vtkFloatArray> arrS =
vtkSmartPointer<vtkFloatArray>::New();
arrS->SetName("Sine");
table->AddColumn(arrS);
// Fill in the table with some example values
int numPoints = 69;
float inc = 7.5 / (numPoints-1);
table->SetNumberOfRows(numPoints);
for (int i = 0; i < numPoints; ++i)
{
table->SetValue(i, 0, i * inc);
table->SetValue(i, 1, cos(i * inc));
table->SetValue(i, 2, sin(i * inc));
}
// Set up the view
vtkSmartPointer<vtkContextView> view =
vtkSmartPointer<vtkContextView>::New();
view->GetRenderer()->SetBackground(1.0, 1.0, 1.0);
// Add multiple line plots, setting the colors etc
vtkSmartPointer<vtkChartXY> chart =
vtkSmartPointer<vtkChartXY>::New();
view->GetScene()->AddItem(chart);
vtkPlot *line = chart->AddPlot(vtkChart::LINE);
line->SetInputData(table, 0, 1);
line->SetColor(0, 255, 0, 255);
line->SetWidth(1.0);
line = chart->AddPlot(vtkChart::LINE);
line->SetInputData(table, 0, 2);
line->SetColor(255, 0, 0, 255);
line->SetWidth(5.0);
// For dotted line, the line type can be from 2 to 5 for different dash/dot
// patterns (see enum in vtkPen containing DASH_LINE, value 2):
#ifndef WIN32
line->GetPen()->SetLineType(vtkPen::DASH_LINE);
#endif
// (ifdef-ed out on Windows because DASH_LINE does not work on Windows
// machines with built-in Intel HD graphics card...)
//view->GetRenderWindow()->SetMultiSamples(0);
// Start interactor
view->GetRenderWindow()->Render();
view->GetInteractor()->Initialize();
view->GetInteractor()->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR)
project(LinePlot)
find_package(VTK COMPONENTS
vtkvtkChartsCore
vtkvtkCommonCore
vtkvtkCommonDataModel
vtkvtkInteractionStyle
vtkvtkRenderingContext2D
vtkvtkRenderingContextOpenGL2
vtkvtkRenderingCore
vtkvtkRenderingFreeType
vtkvtkRenderingGL2PSOpenGL2
vtkvtkRenderingOpenGL2
vtkvtkViewsContext2D QUIET)
if (NOT VTK_FOUND)
message("Skipping LinePlot: ${VTK_NOT_FOUND_MESSAGE}")
return ()
endif()
message (STATUS "VTK_VERSION: ${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
# old system
include(${VTK_USE_FILE})
add_executable(LinePlot MACOSX_BUNDLE LinePlot.cxx )
target_link_libraries(LinePlot PRIVATE ${VTK_LIBRARIES})
else ()
# include all components
add_executable(LinePlot MACOSX_BUNDLE LinePlot.cxx )
target_link_libraries(LinePlot PRIVATE ${VTK_LIBRARIES})
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS LinePlot
MODULES ${VTK_LIBRARIES}
)
endif ()
Download and Build LinePlot¶
Click here to download LinePlot and its CMakeLists.txt file. Once the tarball LinePlot.tar has been downloaded and extracted,
cd LinePlot/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:
./LinePlot
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.