vtk下自由绘制着色问题

Question

vtk下自由绘制着色问题
其他软件效果，奇数次着色，偶数次不着色

自己绘制的效果，重复区域颜色会加重

Answer 1

//vtkRender
    m_pClipRender = vtkRenderer::New();
    this->m_pClipRender->SetLayer(1);
    this->m_pClipRender->InteractiveOff();
    pWin->AddRenderer(this->m_pClipRender);

    //Polygon
    m_pClipPolygonPolyData = vtkPolyData::New();
    vtkNew<vtkPoints> point;
    m_pClipPolygonPolyData->SetPoints(point);
    vtkNew<vtkCellArray> polys;
    m_pClipPolygonPolyData->SetPolys(polys);

    //vtkPolyDataMapper2D
    m_pClipPolygonMapper = vtkPolyDataMapper2D::New();
    m_pClipPolygonMapper->SetInputData(m_pClipPolygonPolyData);

    //vtkActor2D
    m_pClipPolygon2DActor = vtkActor2D::New();
//    m_pClipPolygon2DActor->GetPositionCoordinate()->SetCoordinateSystemToDisplay();
    m_pClipPolygon2DActor->SetMapper(m_pClipPolygonMapper);

    this->m_pClipRender->AddActor2D(m_pClipPolygon2DActor);

上面是创建Actor，下面是更新PolyData

    auto pInter = static_cast<vtkInterStyleVR*>(this->GetInteractorObserver());
    std::vector<vtkVector2i> vecDisPts = pInter->GetPolygonPoints();

    vtkPoints* points = m_pClipPolygonPolyData->GetPoints();
    points->Reset();
    for (int i = 0; i < vecDisPts.size(); i++)
    {
        points->InsertNextPoint(vecDisPts[i].GetX(), vecDisPts[i].GetY(), 0.0);
    }

    m_pClipPolygonPolyData->Allocate(1, 1);
        vtkPoints* points = m_pClipPolygonPolyData->GetPoints();

        vtkCellArray* polys = vtkCellArray::New();
        polys->InsertNextCell(points->GetNumberOfPoints());
        for (int i = 0; i < points->GetNumberOfPoints(); i++)
        {
            polys->InsertCellPoint(i);
        }
        m_pClipPolygonPolyData->SetPolys(polys);
        polys->Delete();
    
    m_pClipPolygon2DActor->GetProperty()->SetLineWidth(2);
    m_pClipPolygon2DActor->GetProperty()->SetColor(0.0, 1.0, 0.0);
    m_pClipPolygon2DActor->GetProperty()->SetOpacity(0.4);
    
    m_pClipPolygonPolyData->Modified();