1.对于在Mac下如何配置VTK，或者是qt下的.pro文件里面的引入包名，请参考我的上一篇博客Mac+CMake3.13.2+Qt5.12.0+VTK8.1.2 配置安装
2.读取stl文件
3.创建相应的顶点对象、立方体对象、单元数组对象
4.通过读取stl模型里面的单元，将单元的坐标索引赋值给一个二维数组
5.将stl模型里面的顶点坐标，存储到第3步定义的顶点对象里
6.将读取到的单元，赋值到第3步定义的单元数组对象里
7.设定每个顶点的标量值，用于颜色的查找
8.定义颜色表
9.数据的映射
。。。后面的就差不多是初始化并显示了
这里附上main.cpp的完整代码

#include "mainwindow.h"
#include <QApplication>
#include <vtkAutoInit.h>
VTK_MODULE_INIT(vtkRenderingOpenGL2);
VTK_MODULE_INIT(vtkInteractionStyle);
VTK_MODULE_INIT(vtkRenderingFreeType);
//#define vtkRenderingCore_AUTOINIT 4(vtkInteractionStyle,vtkRenderingFreeType,vtkRenderingFreeTypeOpenGL2,vtkRenderingOpenGL2)
//#define vtkRenderingVolume_AUTOINIT 1(vtkRenderingVolumeOpenGL2)

#include <QDebug>//调试用的

#include <vtkVersion.h>
#include <vtkPlaneSource.h>
#include <vtkPolyData.h>
#include <vtkSTLReader.h>
#include <vtkSmartPointer.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkCamera.h>
#include <vtkConeSource.h>
#include <vtkCellArray.h>
#include <vtkFloatArray.h>
#include "vtkPointData.h"
#include "vtkPoints.h"
#include "vtkPolyData.h"
#include "vtkPolyDataMapper.h"
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkLookupTable.h>

using namespace std;

int main(int, char *[])
{

    std::string inputFilename="/Users/chentingxuan/Desktop/1.stl";//stl文件路径

    //读取stl文件
    vtkSmartPointer<vtkSTLReader> reader = vtkSmartPointer<vtkSTLReader>::New();
        reader->SetFileName(inputFilename.c_str());
        reader->Update();

        //创建mapper
        vtkSmartPointer<vtkPolyDataMapper> mapper =
               vtkSmartPointer<vtkPolyDataMapper>::New();
           mapper->SetInputConnection(reader->GetOutputPort());


  //创建对象
  vtkPolyData *cube = vtkPolyData::New();//立方体
  vtkPoints *points = vtkPoints::New();//顶点坐标
  vtkCellArray *polys=vtkCellArray::New();//单元数组

  //存储标量值
  vtkFloatArray *scalars = vtkFloatArray::New();

  vtkPolyData *polydata=reader->GetOutput();

  //用于动态创建二维数组,用于存储顶点的索引
  vtkIdType (*y)[3] = new vtkIdType[polydata->GetNumberOfCells()][3];

  //读取细胞单元，并将坐标的索引赋值给二维数组y
  for(int i =0;i<polydata->GetNumberOfCells();i++)
  {
      //l1=polydata->GetCell(i)->GetPointIds();
      y[i][0]=polydata->GetCell(i)->GetPointIds()->GetId(0);

      y[i][1]=polydata->GetCell(i)->GetPointIds()->GetId(1);

      y[i][2]=polydata->GetCell(i)->GetPointIds()->GetId(2);

  }

  //存储顶点
  for(int i=0;i<polydata->GetNumberOfPoints();i++)
  {
      double x[]={0,0,0};
      polydata->GetPoint(i,x);//获取顶点坐标
      points->InsertPoint(i,x);//将顶点坐标插入到vtkPoints定义的points
  }

  //设定单元
  for(int i=0;i<polydata->GetNumberOfCells();i++)
  {
     polys->InsertNextCell(3,y[i]);
  }
  //存储每个顶点的标量值,也就是颜色的索引值，这里暂时是以顶点的先后顺序来设定的
  for(int i=0;i<polydata->GetNumberOfPoints();i++)
  {
      scalars->InsertTuple1(i,i);
  }

  //创建多边形数据
  cube->SetPoints(points);
  //设定单元类型为多边形
  cube->SetPolys(polys);
  //设定每个顶点的标量值
  cube->GetPointData()->SetScalars(scalars);

  points->Delete();
  polys->Delete();
  scalars->Delete();

  //定义颜色映射表
  vtkLookupTable *pColorTable = vtkLookupTable::New();

  //设置颜色表中的颜色，下列两种方式都可以
  /*
  pColorTable->SetNumberOfColors(4);
  pColorTable->SetTableValue(0,1.0,0.0,0.0,1.0);
  pColorTable->SetTableValue(0,1.0,0.0,0.0,1.0);
  pColorTable->SetTableValue(1,0.0,1.0,0.0,1.0);
  pColorTable->SetTableValue(2,1.0,1.0,0.0,1.0);
  pColorTable->SetTableValue(3,0.0,0.0,1.0,1.0);
  */
  //设置颜色表中的颜色
  pColorTable->SetNumberOfColors(256);
  pColorTable->SetHueRange(0.67, 0.0);        //色调范围从红色到蓝色

  pColorTable->Build();

  //数据映射
    vtkPolyDataMapper *cubeMapper = vtkPolyDataMapper::New();
    cubeMapper->SetInputData(cube);
    cubeMapper->SetScalarRange(0,polydata->GetNumberOfPoints()-1);
    cubeMapper->SetLookupTable(pColorTable);
    vtkActor *cubeActor = vtkActor::New();
    cubeActor->SetMapper(cubeMapper);
qDebug()<<"admin"<<polydata->GetNumberOfPoints();

  // Create a renderer(渲染器), render window and interactor(渲染窗口)
  vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
  vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->AddRenderer(renderer);
  renderWindow->SetSize(1300,1300);//设置窗口大小
  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = vtkSmartPointer<vtkRenderWindowInteractor>::New();
  renderWindowInteractor->SetRenderWindow(renderWindow);

  // Add the actors to the scene
  renderer->AddActor(cubeActor);
  renderer->SetBackground(.1,.2,.3); // Background color dark blue

  // Render and interact
  renderWindow->Render();
  renderWindowInteractor->Start();



  return EXIT_SUCCESS;
}

运行结果如下：