vtk opencascade 绘制矩形C++代码

以下是使用VTK和OpenCASCADE库绘制矩形的C++代码示例：

#include <vtkSmartPointer.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkActor.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkCubeSource.h>
#include <vtkOpenCASCADEImporter.h>
#include <vtkOpenCASCADESurfaceMeshSource.h>

int main()
{
    // Create a renderer and a render window
    vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
    vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New();
    renderWindow->AddRenderer(renderer);

    // Create a cube source to generate a unit cube
    vtkSmartPointer<vtkCubeSource> cubeSource = vtkSmartPointer<vtkCubeSource>::New();
    cubeSource->SetCenter(0, 0, 0);
    cubeSource->SetXLength(1);
    cubeSource->SetYLength(1);
    cubeSource->SetZLength(0);

    // Create a surface mesh source using OpenCASCADE
    vtkSmartPointer<vtkOpenCASCADESurfaceMeshSource> surfaceMeshSource = vtkSmartPointer<vtkOpenCASCADESurfaceMeshSource>::New();
    surfaceMeshSource->SetInputConnection(cubeSource->GetOutputPort());
    surfaceMeshSource->Update();

    // Create a polydata mapper and an actor
    vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
    mapper->SetInputConnection(surfaceMeshSource->GetOutputPort());
    vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();
    actor->SetMapper(mapper);
    actor->GetProperty()->SetColor(0.8, 0.8, 0.8);

    // Add the actor to the renderer and set the background color
    renderer->AddActor(actor);
    renderer->SetBackground(0.1, 0.2, 0.4);

    // Set up the render window and interactor
    renderWindow->SetSize(640, 480);
    vtkSmartPointer<vtkRenderWindowInteractor> interactor = vtkSmartPointer<vtkRenderWindowInteractor>::New();
    interactor->SetRenderWindow(renderWindow);

    // Start the render loop
    renderWindow->Render();
    interactor->Start();

    return 0;
}
``