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①ICP配算法的运用，②运用ICP的配准矩阵
二：代码及注释
import vtkmodules.vtkRenderingOpenGL2 import vtkmodules.vtkInteractionStyle from vtkmodules.vtkCommonCore import vtkPoints from vtkmodules.vtkCommonDataModel import vtkCellArray, vtkPolyData, vtkIterativeClosestPointTransform from vtkmodules.vtkFiltersGeneral import vtkTransformPolyDataFilter # from vtkmodules.vtkFiltersSources import def main(): """ 原文写法 sourcePoints = vtkPoints() sourceVertices = vtkCellArray() sp_id = sourcePoints.InsertNextPoint(1.0, 0.1, 0.0) # 返回为0 sourceVertices.InsertNextCell(1) sourceVertices.InsertCellPoint(sp_id) sp_id = sourcePoints.InsertNextPoint(0.1, 1.1, 0.0) # 返回为1 sourceVertices.InsertNextCell(1) sourceVertices.InsertCellPoint(sp_id) sp_id = sourcePoints.InsertNextPoint(0.0, 0.1, 1.0) # 返回为2 sourceVertices.InsertNextCell(1) sourceVertices.InsertCellPoint(sp_id) source = vtkPolyData() source.SetPoints(sourcePoints) source.SetVerts(sourceVertices) 我觉得这种写法与一般示例的写法出入较大，在这里重写 """ sourcePoints = vtkPoints() sourcePoints.InsertNextPoint(1.0, 0.1, 0.0) sourcePoints.InsertNextPoint(0.1, 1.1, 0.0) sourcePoints.InsertNextPoint(0.0, 0.1, 1.0) sourceCells = vtkCellArray() sourceCells.InsertNextCell(1, [0]) sourceCells.InsertNextCell(1, [1]) sourceCells.InsertNextCell(1, [2]) source = vtkPolyData() source.SetPoints(sourcePoints) source.SetVerts(sourceCells) pointCount = 3 for index in range(pointCount): point = [0, 0, 0] sourcePoints.GetPoint(index, point) print("source point[%s]=%s" % (index, point)) # target_points。目标点位 targetPoints = vtkPoints() targetPoints.InsertNextPoint(1, 0, 0) targetPoints.InsertNextPoint(0, 1, 0) targetPoints.InsertNextPoint(0, 0, 1) targetCells = vtkCellArray() targetCells.InsertNextCell(1, [0]) targetCells.InsertNextCell(1, [1]) targetCells.InsertNextCell(1, [2]) target = vtkPolyData() target.SetPoints(targetPoints) target.SetVerts(targetCells) pointCount = 3 for index in range(pointCount): point = [0, 0, 0] targetPoints.GetPoint(index, point) print("target point[%s]=%s" % (index, point)) # 构建icp icp = vtkIterativeClosestPointTransform() icp.SetSource(source) icp.SetTarget(target) icp.GetLandmarkTransform().SetModeToRigidBody() # 设为刚体，只能旋转和平移，不能缩放 icp.SetMaximumNumberOfIterations(20) # 设置最大迭代次数为20 icp.StartByMatchingCentroidsOn() # 开启ICP算法的质心预匹配步骤，它会在第一次迭代时，先应用一个平移变换，将源点云的质心移动到目标点云的质心位置 icp.Modified() # 通知 VTK 管道，这个对象（icp 变换对象）的参数已被修改 icp.Update() """ vtkTransformPolyDataFilter 将一个 vtkPolyData 数据集应用几何变换，然后生成一个新的、已变换的 vtkPolyData 对象 下面一段代码的含义是指将source乘以ipc得到的4x4配准矩阵 """ icpTransformFilter = vtkTransformPolyDataFilter() icpTransformFilter.SetInputData(source) icpTransformFilter.SetTransform(icp) icpTransformFilter.Update() transformedSource = icpTransformFilter.GetOutput() # ============ display transformed points ============== pointCount = 3 for index in range(pointCount): point = [0, 0, 0] transformedSource.GetPoint(index, point) print("transformed source point[%s]=%s" % (index, point)) if __name__ == '__main__': main()
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