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无序点集三角化及可视化。

ParaView Volume MHD离散点P{ (x,y,z,p),… }插值生成体数据Volume，借用ParaView；导入CSV离散点集File->Open，打开*.csv文件，选择分割符（Field Delimter），生成表格数据。TableToPoints表格数据生成几何点数据。PointVolumeInterpolator几何点数据内插生成Volume，即Uniform Rectilinear Grid。插值方法：VoronoiKernel、ShepardKe

PyVista&VTK Data Model在VTK或PyVista中可视化数据，需要两条信息：数据的几何图形（描述数据在空间中的位置及其值）和拓扑结构cells（描述数据集中的点如何相互连接）。在抽象层，有vtkDataObject，它只是没有几何结构或拓扑结构的数据“点(属性数据)”。其中包含vtkFieldData的数组。在具体类层是vtkDataSet，它将几何图形和拓扑添加到vtkDataObject。与数据集中的每个点或单元关联的是一个特定值。由于这些值必须在空间中定位和连接，所以

ParaView & UE4 Volume RenderParaView 数据处理生成Volume，以mhd文件存储，也可借用PVGeo和Pyvista生成Volume。在UE4中渲染Volume使用Raymacher插件渲染，主要涉及UE4的VolumeTexture。Process VolumePVGeo&Pyvistahttps://blog.youkuaiyun.com/mrbaolong/article/details/124363264?spm=1001.2014.3001.550

Volume ProcessLoad the Data# Load the a TensorMesh and some already processed model data mesh = discretize.TensorMesh.readUBC('craig_chile.msh', directory='data/Craig-Chile')models = {'lpout': mesh.readModelUBC(fileName='Lpout.mod', directory='data/Cr

#define ZERO_VALUE 0#define PI 3.14159265358979//点pos绕中心点CenterPos旋转anglefloat2 RotateCenterPoint(float2 CenterPos,float angle,float2 pos){ return float2( (pos.x - Cen...

常用的包围盒轴对齐包围盒(AABB/Axis-aligned bounding box):包围盒按照坐标系的坐标轴进行排列。有向包围盒(OBB/Oriented bounding box)：包围模型的最小盒子，是根据模型的几何形状来决定包围盒的大小和方向，无需和坐标轴垂直，方向是任意的。可视化比较#include <vtkActor.h>#include <vtkOBBTree.h>#include <vtkCallbackCommand.h>#inc

八叉树可用于索引、抽稀等等。随着八叉树的层级越大，越接近于模型。import vtk# 观察者class SliderObserver(object): def __init__(self, Octree, polyData, renderer): self.Octree = Octree self.level = 0 self.polyData = polyData self.renderer = renderer

RequestUpdateExtent测试1import vtkfrom vtk.util.vtkAlgorithm import VTKPythonAlgorithmBasefrom vtk.util import keys# 元数据requestKey = keys.MakeKey(keys.IntegerRequestKey, "a request", "my module")class MySource(VTKPythonAlgorithmBase): def __init_

一个简单的管线：import vtkfrom vtk.util.vtkAlgorithm import VTKPythonAlgorithmBase class MySource(VTKPythonAlgorithmBase): def __init__(self): VTKPythonAlgorithmBase.__init__(self, nInputPorts=0, nOutputPorts=1, outputType=

vtkInformation 和 vtkInformationVectorvtkInformation 和 vtkInformationVector实际是maps存储着vtk管线中的数据。vtkInformationVector相当于vtkInformation数组。import vtkinfo = vtk.vtkInformation()info.Set(vtk.vtkStreamingDemandDrivenPipeline.UPDATE_PIECE_NUMBER(), 1) print

python自定义vtk算法vtkPythonAlgorithm is great使用vtkPythonAlgorithm定义vtkPythonAlgorithm对象通过SetPythonObject()使用自定义算法对象调用Initialize(self, vtkself)把vtkPythonAlgorithm引用传递给自定义算法对象将以下方法委托给自定义算法对象ProcessRequest(self, vtkself, request, inInfo, outInfo)FillInp

import pyvistaimport omfvistapyvista.set_plot_theme('document')project = omfvista.load_project('data/test_file.omf')projectInformationBlocksMultiBlockValuesN Blocks9X Bounds443941.105, 447059.611Y Bounds491941.536, 495059.859Z Bounds2330.000,

import shapefileimport numpy as npimport vtkimport pyvista# sklearn's KDTree is fast: use it if available# Scipy also also a good KDTreefrom sklearn.neighbors import KDTree as Tree# Define conveinance functions for converting shape files to VTK o

PVGeo-DiscretizeThis notebook demonstrates how to pair PVGeo and discretize for simple processing routines.This notebook is outlined into four sections:Introduction to PVGeoOverview of new VTK interface in discretizePairing PVGeo and discretizeExamp

WIP: Using the pyvista PackageThis notebook is a work in progress to demo how PVGeo can be used with pyvista for creating integrated visualizations directly in a Python environment. At this time, the 3D rendering is perfromed in a separate window and we h

import PVGeoimport numpy as npimport pandas as pdimport pyvistaprint('NumPy Version: %s' % np.__version__)print('PVGeo Version: %s' % PVGeo.__version__)print('pyvista Version: %s' % pyvista.__version__)NumPy Version: 1.18.5PVGeo Version: 2.1.0py

“圆柱”曲面展开沿轴向展开，展开后横坐标为弧长，纵坐标为轴向坐标，高程为曲面到参考圆柱曲面的距离。定义参考圆柱//！轴enum AXIS { AXIS_X, AXIS_Y, AXIS_Z};//! 投影圆柱struct GEO_CYLINDER{ //!轴向 AXIS Axial; //!径向：横/纵 ，横向弧长，纵向偏差 AXIS RadialTran; AXIS RadialLong; //!径向截面圆心中心 double CenterTran; double Ce

paraview 数据可视化用paraview打开plate.vtk，在属性信息一栏中（Information），可以看到有mode1、mode2、mode3、mode4和mode8五种有限元结果属性数据，它们可以表示几何体在每一个点上的位移，vtkWarpVector类可以用这些矢量数据来变形几何体，在该类中可以设置矢量数据以及缩放的比例，控制几何体的变形。原始几何体添加 Filters->WrapByVector ，并选择属性mode1，设置 Scale Factor 为1。变形后的几何

有时候生成的隧道会有缺失（有洞），需要修复填补这些洞。方式一 ：vtkFillHolesFilter vtkSmartPointer<vtkFillHolesFilter> fillHolesFilter = vtkSmartPointer<vtkFillHolesFilter>::New(); fillHolesFilter->SetInputData(input); fillHolesFilter->SetHoleSize(0.5); fillHoles

三维像素化曲面网格（网格曲面的体元化）创建封闭曲面网格和网格体的体元模型。示例演示了如何从包围盒计算隐式距离。体元化步骤确定体元的大小。生成vtkUnStructuredGrid确定体元是否在封闭曲面内或体中def voxelize(mesh, density=None, check_surface=True): """Voxelize mesh to UnstructuredGrid. Parameters ---------- density : fl

pyvista 读取vtk 文件，旋转之后，并另存。import pyvista as pv# 读取polydatamesh=pv.read("door.vtp")mesh.plot()# 绕z 轴旋转180mesh.rotate_z(180)print(mesh)mesh.plot()# 保存旋转之后的结果mesh.save("door.vtp")旋转之前：旋转之后：pyvista 旋转操作源码def axis_rotation(points, angle, inplac

使用曲面进行切割import pyvista as pvimport numpy as npmesh = pv.ParametricRandomHills()mesh.rotate_y(90)surface= mesh.elevation()# Create a grid around that surface# 根据生成的mesh生成网格grid = pv.create_grid(surface)# Clip the grid using the surfacemodel = g

ExtrudePolyDataAlongLine （沿着线拉伸多变形）Obtain the 2D polydata from a file( or generate a disk).第一步获取截面轮廓线（contours）。Generates random points in 3D space and fits a spline to the points.第二步生成放样线，即轮廓线沿着这条线放样。Computes an orientation frame at each point on th

Geometric Objects 绘制预定义简单几何体对象import pyvista as pvcyl = pv.Cylinder()arrow = pv.Arrow()sphere = pv.Sphere()plane = pv.Plane()line = pv.Line()box = pv.Box()cone = pv.Cone()poly = pv.Polygon()disc = pv.Disc()p = pv.Plotter(shape=(3, 3))# Top ro

影像叠加地形图拉伸地形图elevation = elevation_dataobj.warp_by_scalar() 地形图按照高程属性拉伸成曲面贴纹理topo_map = pv.read_texture(image_filename)# Bounds of the aerial imagery - given to usbounds = (1818000,1824500,5645000,5652500,0,3000)# Clip the elevation dataset to the

pyvista is a high-level API to the VTK创建规则网格曲面# sphinx_gallery_thumbnail_number = 2import pyvista as pvimport numpy as np生成一个二维的正弦曲面# Make datax = np.arange(-10, 10, 0.25)y = np.arange(-10, 10, 0.25)x, y = np.meshgrid(x, y)r = np.sqrt(x ** 2 +

VTK Learning Thirty - vtkPolyData to CGAL Surface_meshDescription将vtkPolyData转换成CGAL::Surface_mesh,并利用CGAL的布尔运算对数据进行处理,然后再将处理后的CGAL::Surface_mesh转换成vtkPolyData进行可视化渲染。定义 CGAL::Surface_meshtypedef CGAL::Exact_predicates_inexact_constructions_kernel EP

VTK Learning Twenty-nine- surface normalDescriptionvtkPolyDataNormals计算多边形网格（ polygonal mesh）的法向量。同时能够重新排序多边形顶点的顺序以确保邻接多边形方向一致。能够整体翻转曲面的法向量，使得曲面的法向量方向一致。三维平面的法向量是指垂直于该平面的三维向量。曲面在某点P处的法向量为垂直于该点切平面的向量。对于一个网格模型，每个点和单元cell都可以计算一个法向量，在三维计算机图形学中法向量一个重要的应用

Description利用paraview 生成Box和tube管线，测试vtkbool bool运算。Code#include <vtkXMLPolyDataReader.h>#include<vtkPolyDataMapper.h>#include<vtkActor.h>#include<vtkRenderer.h>#include<vtkRenderWindow.h>#include<vtkRenderWindowInt

vtkTubeFilter可以用来生成包围一条折线的管道。下面是一个vtkTubeFilter的使用例子。围绕一条线创建一条管道。添加一条线添加tube FilterReferencevtkTubeFilter生成管道

VTK Learning Twenty-seven- vtkboolDescriptionvtkbool复杂多变形网格的布尔操作。示例为从正方体中挖去一个圆柱体。Code#include<vtkCubeSource.h>#include<vtkCylinderSource.h>#include<vtkPolyDataMapper.h>#include<vtkActor.h>#include<vtkRenderer.h>#inclu

PointInterpolator - ImageDataDescription利用PointInterpolator插值生成三维栅格数据。属性值受空间位置（x,y,z)影响。生成插值网格体res = 40# Create a probe volumecenter = output.GetCenter()bounds = output.GetBounds()length = out...

vtkPointInterpolator描述interpolate over point cloud using various kernels使用各种核函数插值点云数据vtkPointInterpolator probes a point cloud Pc (the filter Source) with a set of points P (the filter Input), int...

VTK Learning Twenty-three- PointInterpolator2DDescription对地形数据高程偏移（根据高程属性来确定Z值），并根据模拟的属性值确定地形数据的属性。Code#!/usr/bin/env pythonimport vtkfrom vtk.util.misc import vtkGetDataRootVTK_DATA_ROOT = vtk...

VTK Learning Twenty-three- PointInterpolator2DDescriptionuse terrain dataset. Just for kicks we’ll treat the elevations as a “point cloud” and interpolate the elevation onto a plane.使用DEM数据。在平面上内插高...

网格平滑vtkSmoothPolyDataFilter网格平滑是一种调整数据集中点坐标的技术。网格平滑的目的是提高网格的外观和提高单元数据集的形状。在平滑过程中，不会改变数据集的拓扑结构，只改变几何结构。网格平滑的应用包括提高等值面的外观，或者作为移除表面噪声的模型工具。通过应用网格平滑，模型的外观能够动态地提高。拉普拉斯平滑是一种常用的平滑算法。`VTK`中 的`vtkSmoothPol...

vtk python3环境安装配置安装miniconda下载地址：https://docs.conda.io/en/latest/miniconda.htmlhttps://docs.conda.io/en/latest/miniconda.html#windows-installers创建环境conda create env --name vtk安装vtk包conda instal...

VTK Learning Twenty-two- fault triangulationDescriptionCreate a constrained Delaunay triangulation following fault lines. Thefault lines serve as constraint edges in the Delaunay triangulation.根据断...