一：主要的知识点
1、说明
本文只是教程内容的一小段，因博客字数限制，故进行拆分。主教程链接：vtk教程——逐行解析官网所有Python示例-CSDN博客
2、知识点纪要
本段代码主要涉及的有①平面着色与高洛德着色的区别
二：代码及注释
import vtkmodules.vtkRenderingOpenGL2 import vtkmodules.vtkInteractionStyle from vtkmodules.vtkCommonColor import vtkNamedColors from vtkmodules.vtkIOGeometry import vtkOBJReader from vtkmodules.vtkFiltersSources import vtkSphereSource, vtkCylinderSource from collections import OrderedDict from vtkmodules.vtkRenderingCore import vtkPolyDataMapper, vtkActor, vtkRenderer, vtkRenderWindow, \ vtkRenderWindowInteractor from vtkmodules.vtkCommonDataModel import vtkQuadric from vtkmodules.vtkImagingHybrid import vtkSampleFunction from vtkmodules.vtkFiltersCore import vtkContourFilter def CreateIsoSurface(flat): quadric = vtkQuadric() quadric.SetCoefficients(1, 2, 3, 0, 1, 0, 0, 0, 0, 0) sample = vtkSampleFunction() sample.SetSampleDimensions(25, 25, 25) sample.SetImplicitFunction(quadric) # Generate the implicit surface. contour = vtkContourFilter() contour.SetInputConnection(sample.GetOutputPort()) range = [1.0, 6.0] contour.GenerateValues(5, range) # Map the contour. contourMapper = vtkPolyDataMapper() contourMapper.SetInputConnection(contour.GetOutputPort()) contourMapper.SetScalarRange(0, 7) actor = vtkActor() actor.SetMapper(contourMapper) if flat: actor.GetProperty().SetInterpolationToFlat() else: actor.GetProperty().SetInterpolationToGouraud() renderer = vtkRenderer() renderer.AddActor(actor) return renderer def CreateModel(flat, fileName): ''' :param flat: The interpolation to use (flat or Gouraud). :param fileName: The file name. :return: the renderer ''' colors = vtkNamedColors() reader = vtkOBJReader() reader.SetFileName(fileName) mapper = vtkPolyDataMapper() mapper.SetInputConnection(reader.GetOutputPort()) actor = vtkActor() actor.SetMapper(mapper) actor.GetProperty().SetColor(colors.GetColor3d('Tan')) if flat: actor.GetProperty().SetInterpolationToFlat() else: actor.GetProperty().SetInterpolationToGouraud() renderer = vtkRenderer() renderer.AddActor(actor) return renderer def CreateCylinder(flat): colors = vtkNamedColors() cylinder = vtkCylinderSource() mapper = vtkPolyDataMapper() mapper.SetInputConnection(cylinder.GetOutputPort()) actor = vtkActor() actor.SetMapper(mapper) actor.GetProperty().SetColor(colors.GetColor3d('MistyRose')) if flat: actor.GetProperty().SetInterpolationToFlat() else: actor.GetProperty().SetInterpolationToGouraud() renderer = vtkRenderer() renderer.AddActor(actor) return renderer def CreateSphere(flat): colors = vtkNamedColors() sphere = vtkSphereSource() mapper = vtkPolyDataMapper() mapper.SetInputConnection(sphere.GetOutputPort()) actor = vtkActor() actor.SetMapper(mapper) actor.GetProperty().SetColor(colors.GetColor3d('MistyRose')) if flat: actor.GetProperty().SetInterpolationToFlat() else: actor.GetProperty().SetInterpolationToGouraud() renderer = vtkRenderer() renderer.AddActor(actor) return renderer def main(): """ 平面着色 SetInterpolationToFlat 原理: 对多边形（三角形或四边形）的整个表面使用一个恒定的颜色和法向量计算亮度 视觉效果: 结果是棱角分明的。可以看到组成曲面的各个多边形的边界，常用于显示模型的实际拓扑结构或模拟低多边形艺术风格 高洛德着色 SetInterpolationToGouraud 原理: 在多边形的顶点处计算颜色和亮度，然后将这些颜色值在多边形内部进行线性插值 视觉效果: 结果是平滑且连续的。它极大地减少了多边形边缘的可见性，使低分辨率的曲面看起来更圆滑，更逼真 """ colors = vtkNamedColors() fileName = "Data/cow.obj" renderers = OrderedDict() renderers['flatSphereRenderer'] = CreateSphere(True) renderers['flatCylinderRenderer'] = CreateCylinder(True) renderers['flatIsoSurfaceRenderer'] = CreateIsoSurface(True) renderers['flatModelRenderer'] = CreateModel(True, fileName) renderers['smoothSphereRenderer'] = CreateSphere(False) renderers['smoothCylinderRenderer'] = CreateCylinder(False) renderers['smoothIsoSurfaceRenderer'] = CreateIsoSurface(False) renderers['smoothModelRenderer'] = CreateModel(False, fileName) keys = list(renderers.keys()) renderWindow = vtkRenderWindow() # Setup the viewports for the renderers. rendererSize = 256 xGridDimensions = 4 yGridDimensions = 2 renderWindow.SetSize(rendererSize * xGridDimensions, rendererSize * yGridDimensions) renderWindow.SetWindowName('FlatVersusGouraud') for row in range(0, yGridDimensions): for col in range(0, xGridDimensions): # (xmin, ymin, xmax, ymax) viewport = [0] * 4 viewport[0] = col / xGridDimensions viewport[1] = (yGridDimensions - (row + 1)) / yGridDimensions viewport[2] = (col + 1) / xGridDimensions viewport[3] = (yGridDimensions - row) / yGridDimensions index = row * xGridDimensions + col renderers[keys[index]].SetViewport(viewport) for r in range(0, len(renderers)): renderers[keys[r]].SetBackground(colors.GetColor3d('SlateGray')) renderers[keys[r]].GetActiveCamera().Azimuth(20) renderers[keys[r]].GetActiveCamera().Elevation(30) renderers[keys[r]].ResetCamera() if r > 3: renderers[keys[r]].SetActiveCamera(renderers[keys[r - 4]].GetActiveCamera()) renderWindow.AddRenderer(renderers[keys[r]]) interactor = vtkRenderWindowInteractor() interactor.SetRenderWindow(renderWindow) renderWindow.Render() interactor.Start() if __name__ == '__main__': main()
