目录

VTK的编译与环境搭建

VTK一般渲染流程

VTK数据类型-vtkPolyData

使用vtk自带的多边形数据

 使用自己创建的数据

添加顶点颜色

添加面颜色

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VTK的编译与环境搭建

这部分目前已经有了大佬做了成熟的傻瓜式配置，大家可以参考这篇文章：VTK+VS2019(或其他版本均可) 傻瓜式一站式 配置_Nancy_fairy的博客-CSDN博客_vs2019 vtk

VTK一般渲染流程

这部分的介绍也很多，大家可以参考这篇文章：VTK笔记-了解VTK_黑山老妖的博客-CSDN博客_vtk应用领域最近，重新学习了VTK相关内容，网上资料质量参差不齐，自己从多处搜集资料，整理记录之；VTK简介Vtk，（visualization toolkit）是一个开源的免费软件系统，主要用于三维计算机图形学、图像处理和可视化。Vtk是在面向对象原理的基础上设计和实现的，它的内核是用C++构建的，包含有大约250,000行代码，2000多个类，还包含有几个转换界面，因此也可以自由的通过Java，Tcl/Tk和Python各种语言使用vtk。视觉化工具函式库（VTK，Visualization Toolkit）https://blog.csdn.net/liushao1031177/article/details/115503446

VTK数据类型-vtkPolyData

多边形数据集主要由顶点、多顶点、线、折线和三角形地带等单元组成。
顶点、线和多边形构成了用来表达0、1和2维几何图形的基本要素的最小集合。特别是三角形带，表达N个三角形仅需N+2个点，且大多数图形渲染三角形带速度极快。

使用vtk自带的多边形数据

vtk自带很多的成熟的多边形数据，包括圆柱，球体，锥体等。我们仅需设置几个属性就可以使用现成的数据创建模型并显示。以下为创建显示锥体的代码

void SimpleVtk()
{vtkConeSource* source = vtkConeSource::New();source->SetHeight(13);source->SetRadius(5);vtkPolyDataMapper* coneMapper = vtkPolyDataMapper::New();coneMapper->SetInputConnection(source->GetOutputPort());vtkActor* coneActor = vtkActor::New();coneActor->SetMapper(coneMapper);vtkRenderer* render = vtkRenderer::New();vtkRenderWindow* renwin = vtkRenderWindow::New();vtkRenderWindowInteractor* iren = vtkRenderWindowInteractor::New();render->AddActor(coneActor);render->SetBackground(0.8, 0.4, 0.4);renwin->AddRenderer(render);iren->SetRenderWindow(renwin);iren->Initialize();iren->Start();source->Delete();coneMapper->Delete();coneActor->Delete();render->Delete();renwin->Delete();iren->Delete();
}

首先创建锥体资源，并设置其属性，紧接着将其传递给映射器，映射器将结果传递给渲染组件进行渲染显示。以下为运行的结果：

 使用自己创建的数据

当然有时候默认的模型会不够用，我们想要自己创建模型。以下为创建一个四面体的代码：

void makePolyData()
{vtkPoints* points = vtkPoints::New();points->InsertNextPoint(0.0, 0.0, 0.0);points->InsertNextPoint(1.0, 0.0, 0.0);points->InsertNextPoint(0.0, 1.0, 0.0);points->InsertNextPoint(0.0, 0.0, 1.0);vtkTriangle* tran1 = vtkTriangle::New();tran1->GetPointIds()->SetId(0, 0);tran1->GetPointIds()->SetId(1, 1);tran1->GetPointIds()->SetId(2, 2);vtkTriangle* tran2 = vtkTriangle::New();tran2->GetPointIds()->SetId(0, 0);tran2->GetPointIds()->SetId(1, 1);tran2->GetPointIds()->SetId(2, 3);vtkTriangle* tran3 = vtkTriangle::New();tran3->GetPointIds()->SetId(0, 0);tran3->GetPointIds()->SetId(1, 2);tran3->GetPointIds()->SetId(2, 3);vtkTriangle* tran4 = vtkTriangle::New();tran4->GetPointIds()->SetId(0, 1);tran4->GetPointIds()->SetId(1, 2);tran4->GetPointIds()->SetId(2, 3);vtkCellArray* cells = vtkCellArray::New();cells->InsertNextCell(tran1);cells->InsertNextCell(tran2);cells->InsertNextCell(tran3);cells->InsertNextCell(tran4);vtkPolyData* source = vtkPolyData::New();source->SetPoints(points);source->SetPolys(cells);vtkPolyDataMapper* coneMapper = vtkPolyDataMapper::New();coneMapper->SetInputData(source);vtkActor* coneActor = vtkActor::New();coneActor->SetMapper(coneMapper);vtkRenderer* render = vtkRenderer::New();vtkRenderWindow* renwin = vtkRenderWindow::New();vtkRenderWindowInteractor* iren = vtkRenderWindowInteractor::New();render->AddActor(coneActor);render->SetBackground(0.8, 0.4, 0.4);renwin->AddRenderer(render);iren->SetRenderWindow(renwin);iren->Initialize();iren->Start();points->Delete();tran1->Delete();tran2->Delete();tran3->Delete();tran4->Delete();cells->Delete();source->Delete();coneMapper->Delete();coneActor->Delete();render->Delete();renwin->Delete();iren->Delete();
}

首先创建点资源，并通过InsertNextPoint方法添加坐标点，其次创建四面体的四个三角形，通过GetPointIds()->SetId()方法设置点的索引，然后再将四个三角形通过InsertNextCell方法添加进多边形单元中。再然后将点资源和多边形单元添加到vtkPolyData中，将Data置入渲染流程即可显示这个四面体。以下为输出的结果：

 很显然这种生成方式略显繁琐，vtk可以添加三角形带进入多边形单元中。一般情况下的3D模型都是由三角形带组成的，且三角形带非常节约资源且渲染速度快。以下为三角形带的代码：

void makePolyData2()
{vtkPoints* points = vtkPoints::New();points->InsertNextPoint(0.0, 0.0, 0.0);points->InsertNextPoint(1.0, 0.0, 0.0);points->InsertNextPoint(0.0, 1.0, 0.0);points->InsertNextPoint(0.0, 0.0, 1.0);vtkCellArray* array = vtkCellArray::New();array->InsertNextCell(6);array->InsertCellPoint(1);array->InsertCellPoint(3);array->InsertCellPoint(0);array->InsertCellPoint(2);array->InsertCellPoint(1);array->InsertCellPoint(3);vtkPolyData* source = vtkPolyData::New();source->SetPoints(points);source->SetStrips(array);vtkPolyDataMapper* coneMapper = vtkPolyDataMapper::New();coneMapper->SetInputData(source);vtkActor* coneActor = vtkActor::New();coneActor->SetMapper(coneMapper);vtkRenderer* render = vtkRenderer::New();vtkRenderWindow* renwin = vtkRenderWindow::New();vtkRenderWindowInteractor* iren = vtkRenderWindowInteractor::New();render->AddActor(coneActor);render->SetBackground(0.8, 0.4, 0.4);renwin->AddRenderer(render);iren->SetRenderWindow(renwin);iren->Initialize();iren->Start();points->Delete();array->Delete();source->Delete();coneMapper->Delete();coneActor->Delete();render->Delete();renwin->Delete();iren->Delete();
}

通过InsertCellPoint方法将点的索引添加进三角带中，在资源中使用SetStrips添加三角带。以下为渲染结果：

添加顶点颜色

 既然我们已经成功的生成了四面体，但他是灰色的，显然不是很好看。以下为添加颜色显示的代码，首先是添加顶点颜色：

void makePolyDataAndSetColor()
{unsigned char red[3] = { 255, 0, 0 };unsigned char green[3] = { 0, 255, 0 };unsigned char blue[3] = { 0, 0, 255 };vtkPoints* points = vtkPoints::New();points->InsertNextPoint(0.0, 0.0, 0.0);points->InsertNextPoint(1.0, 0.0, 0.0);points->InsertNextPoint(0.0, 1.0, 0.0);points->InsertNextPoint(0.0, 0.0, 1.0);vtkCellArray* array = vtkCellArray::New();array->InsertNextCell(6);array->InsertCellPoint(1);array->InsertCellPoint(3);array->InsertCellPoint(0);array->InsertCellPoint(2);array->InsertCellPoint(1);array->InsertCellPoint(3);vtkUnsignedCharArray* pointsColors = vtkUnsignedCharArray::New();pointsColors->SetNumberOfComponents(3);pointsColors->InsertNextTypedTuple(red);pointsColors->InsertNextTypedTuple(green);pointsColors->InsertNextTypedTuple(blue);pointsColors->InsertNextTypedTuple(red);vtkPolyData* source = vtkPolyData::New();source->SetPoints(points);source->SetStrips(array);source->GetPointData()->SetScalars(pointsColors);vtkPolyDataMapper* coneMapper = vtkPolyDataMapper::New();coneMapper->SetInputData(source);vtkActor* coneActor = vtkActor::New();coneActor->SetMapper(coneMapper);vtkRenderer* render = vtkRenderer::New();vtkRenderWindow* renwin = vtkRenderWindow::New();vtkRenderWindowInteractor* iren = vtkRenderWindowInteractor::New();render->AddActor(coneActor);render->SetBackground(0.8, 0.4, 0.4);renwin->AddRenderer(render);iren->SetRenderWindow(renwin);iren->Initialize();iren->Start();points->Delete();array->Delete();pointsColors->Delete();source->Delete();coneMapper->Delete();coneActor->Delete();render->Delete();renwin->Delete();iren->Delete();
}

新建一个unsignedchar数组作为颜色资源，将颜色通过InsertNextTypedTuple()方法加入到颜色资源中。然后将顶点颜色资源通过GetPointData()->SetScalars()方法加入到polyData中。以下为渲染结果：

添加面颜色

当然我们也可以给每个面添加纯色：

void makePolyDataAndSetColor2()
{unsigned char red[3] = { 255, 0, 0 };unsigned char green[3] = { 0, 255, 0 };unsigned char blue[3] = { 0, 0, 255 };vtkPoints* points = vtkPoints::New();points->InsertNextPoint(0.0, 0.0, 0.0);points->InsertNextPoint(1.0, 0.0, 0.0);points->InsertNextPoint(0.0, 1.0, 0.0);points->InsertNextPoint(0.0, 0.0, 1.0);vtkTriangle* tran1 = vtkTriangle::New();tran1->GetPointIds()->SetId(0, 0);tran1->GetPointIds()->SetId(1, 1);tran1->GetPointIds()->SetId(2, 2);vtkTriangle* tran2 = vtkTriangle::New();tran2->GetPointIds()->SetId(0, 0);tran2->GetPointIds()->SetId(1, 1);tran2->GetPointIds()->SetId(2, 3);vtkTriangle* tran3 = vtkTriangle::New();tran3->GetPointIds()->SetId(0, 0);tran3->GetPointIds()->SetId(1, 2);tran3->GetPointIds()->SetId(2, 3);vtkTriangle* tran4 = vtkTriangle::New();tran4->GetPointIds()->SetId(0, 1);tran4->GetPointIds()->SetId(1, 2);tran4->GetPointIds()->SetId(2, 3);vtkCellArray* cells = vtkCellArray::New();cells->InsertNextCell(tran1);cells->InsertNextCell(tran2);cells->InsertNextCell(tran3);cells->InsertNextCell(tran4);vtkUnsignedCharArray* cellColors = vtkUnsignedCharArray::New();cellColors->SetNumberOfComponents(3);cellColors->InsertNextTypedTuple(red);cellColors->InsertNextTypedTuple(green);cellColors->InsertNextTypedTuple(blue);cellColors->InsertNextTypedTuple(red);vtkPolyData* source = vtkPolyData::New();source->SetPoints(points);source->SetPolys(cells);source->GetCellData()->SetScalars(cellColors);vtkPolyDataMapper* coneMapper = vtkPolyDataMapper::New();coneMapper->SetInputData(source);vtkActor* coneActor = vtkActor::New();coneActor->SetMapper(coneMapper);vtkRenderer* render = vtkRenderer::New();vtkRenderWindow* renwin = vtkRenderWindow::New();vtkRenderWindowInteractor* iren = vtkRenderWindowInteractor::New();render->AddActor(coneActor);render->SetBackground(0.8, 0.4, 0.4);renwin->AddRenderer(render);iren->SetRenderWindow(renwin);iren->Initialize();iren->Start();points->Delete();cellColors->Delete();tran1->Delete();tran2->Delete();tran3->Delete();tran4->Delete();cells->Delete();source->Delete();coneMapper->Delete();coneActor->Delete();render->Delete();renwin->Delete();iren->Delete();
}

 这次用的是GetCellData()->SetScalars()方法将面颜色传递给各个面。渲染结果如下：

 大家也可以试试同时添加顶点颜色和面颜色是什么效果。