网站推广,广州市地图,wordpress archlinux,个性flash网站判断 一个点 ,判断是否在风格 stl 模型内部#xff0c;或表面#xff1a;
目录
1.方案一#xff1a;使用vtkCellLocator FindClosestPoint 找到模型上距离给定点最近的一点#xff0c;计算两点的距离 #xff0c;小于某一阈值 则认为此点在模型上#xff1b;
2.方案二…判断 一个点 ,判断是否在风格 stl 模型内部或表面
目录
1.方案一使用vtkCellLocator FindClosestPoint 找到模型上距离给定点最近的一点计算两点的距离 小于某一阈值 则认为此点在模型上
2.方案二 使用 vtkKdTreePointLocator
3.方案三 使用 vtkSelectEnclosedPoints 1.方案一使用vtkCellLocator FindClosestPoint 找到模型上距离给定点最近的一点计算两点的距离 小于某一阈值 则认为此点在模型上
vtkCellLocator本身是一个octree。典型的用法就是求最近的单元或者点
bool CheckPointInsidePolyData(vtkPolyData * poly, double* pt)
{bool insidefalse; auto cellLocator vtkSmartPointervtkCellLocator::New();cellLocator-SetDataSet(poly);cellLocator-BuildLocator();auto assistCell vtkSmartPointervtkGenericCell::New();double closestPoint[3];//the coordinates of the closest point will be returned heredouble closestPointDist2; //the squared distance to the closest point will be returned herevtkIdType cellId; //the cell id of the cell containing the closest point will be returned hereint subId-1;cellLocator-FindClosestPoint(point, closestPoint, assistCell, cellId, subId, closestPointDist2);if (-1! subIdclosestPointDist2 0.001){return true;}return inside;
}
2.方案二 使用 vtkKdTreePointLocator
但这个只能找到最新的点还需要自己判断一下距离
官方样例
#include vtkIdList.h
#include vtkKdTreePointLocator.h
#include vtkNew.h
#include vtkPoints.h
#include vtkPolyData.hint main(int, char*[])
{// Setup point coordinatesdouble x[3] {1.0, 0.0, 0.0};double y[3] {0.0, 1.0, 0.0};double z[3] {0.0, 0.0, 1.0};vtkNewvtkPoints points;points-InsertNextPoint(x);points-InsertNextPoint(y);points-InsertNextPoint(z);vtkNewvtkPolyData polydata;polydata-SetPoints(points);// Create the treevtkNewvtkKdTreePointLocator kDTree;kDTree-SetDataSet(polydata);kDTree-BuildLocator();double testPoint[3] {2.0, 0.0, 0.0};// Find the closest points to TestPointvtkIdType iD kDTree-FindClosestPoint(testPoint);std::cout The closest point is point iD std::endl;// Get the coordinates of the closest pointdouble closestPoint[3];kDTree-GetDataSet()-GetPoint(iD, closestPoint);std::cout Coordinates: closestPoint[0] closestPoint[1] closestPoint[2] std::endl;return EXIT_SUCCESS;
}
3.方案三 使用 vtkSelectEnclosedPoints
vtkSelectEnclosedPoints类可以判断标记点是否在封闭表面内。 vtkSelectEnclosedPoints是一个Filter它计算所有输入点以确定它们是否位于封闭曲面中。过滤器生成一个0,1掩码以vtkDataArray的形式指示点是在提供的曲面的外部掩码值0还是内部掩码值1(输出vtkDataArray的名称是“SelectedPoints”。 运行过滤器后可以通过调用IsInsideptId方法来查询点是否在内部/外部。
样例判断三个点是否在立方体内
注意在立方体边上的点不属于在立方体内部 CODE
#include vtkVersion.h
#include vtkPolyData.h
#include vtkPointData.h
#include vtkCubeSource.h
#include vtkSmartPointer.h
#include vtkSelectEnclosedPoints.h
#include vtkIntArray.h
#include vtkDataArray.h
#include vtkProperty.h
#include vtkPolyDataMapper.h
#include vtkActor.h
#include vtkRenderWindow.h
#include vtkRenderer.h
#include vtkRenderWindowInteractor.hint main(int, char*[])
{vtkNewvtkCubeSource cubeSource;cubeSource-Update();vtkPolyData* cube cubeSource-GetOutput();double testInside[3] { 0.0, 0.0, 0.0 };double testOutside[3] { 0.7, 0.0, 0.0 };double testBorderOutside[3] { 0.5, 0.0, 0.0 };vtkNewvtkPoints points;points-InsertNextPoint(testInside);points-InsertNextPoint(testOutside);points-InsertNextPoint(testBorderOutside);vtkNewvtkPolyData pointsPolydata;pointsPolydata-SetPoints(points);//Points inside testvtkNewvtkSelectEnclosedPoints selectEnclosedPoints;selectEnclosedPoints-SetInputData(pointsPolydata);selectEnclosedPoints-SetSurfaceData(cube);selectEnclosedPoints-Update();for (unsigned int i 0; i 3; i) {std::cout Point i : selectEnclosedPoints-IsInside(i) std::endl;}vtkDataArray* insideArray vtkDataArray::SafeDownCast(selectEnclosedPoints-GetOutput()-GetPointData()-GetArray(SelectedPoints));for (vtkIdType i 0; i insideArray-GetNumberOfTuples(); i) {std::cout i : insideArray-GetComponent(i, 0) std::endl;}//Cube mapper, actorvtkNewvtkPolyDataMapper cubeMapper;cubeMapper-SetInputConnection(cubeSource-GetOutputPort());vtkNewvtkActor cubeActor;cubeActor-SetMapper(cubeMapper);cubeActor-GetProperty()-SetOpacity(0.5);//First, apply vtkVertexGlyphFilter to make cells around points, vtk only render cells.vtkNewvtkVertexGlyphFilter vertexGlyphFilter;vertexGlyphFilter-AddInputData(pointsPolydata);vertexGlyphFilter-Update();vtkNewvtkPolyDataMapper pointsMapper;pointsMapper-SetInputConnection(vertexGlyphFilter-GetOutputPort());vtkNewvtkActor pointsActor;pointsActor-SetMapper(pointsMapper);pointsActor-GetProperty()-SetPointSize(5); pointsActor-GetProperty()-SetColor(1.0, 0.0, 0);//Create a renderer, render window, and interactorvtkNewvtkRenderer renderer;vtkNewvtkRenderWindow renderWindow;renderWindow-AddRenderer(renderer);vtkNewvtkRenderWindowInteractor renderWindowInteractor;renderWindowInteractor-SetRenderWindow(renderWindow);// Add the actor to the scenerenderer-AddActor(cubeActor);renderer-AddActor(pointsActor);renderer-SetBackground(.0, 1, .0);renderWindow-Render();renderWindowInteractor-Start();return EXIT_SUCCESS;
}
输出
Point 0: 1
Point 1: 0
Point 2: 0
0 : 1
1 : 0
2 : 0
