在VTK中 使用OpenMP并行创建非结构化数据集
时间: 2024-03-07 17:41:41 浏览: 20
VTK是一个用于可视化和图形处理的开源库。它提供了很多用于创建、处理和呈现数据的工具和算法,包括可视化非结构化数据集的功能。在VTK中使用OpenMP并行创建非结构化数据集可以提高效率,加速计算过程。
以下是使用OpenMP并行创建非结构化数据集的步骤:
1. 导入必要的头文件和命名空间。
```c++
#include <vtkUnstructuredGrid.h>
#include <vtkPoints.h>
#include <vtkCellArray.h>
#include <vtkSmartPointer.h>
#include <vtkFloatArray.h>
#include <vtkXMLUnstructuredGridWriter.h>
#include <vtkXMLPUnstructuredGridWriter.h>
#include <omp.h>
using namespace std;
```
2. 定义网格的参数,包括网格大小和网格分辨率。
```c++
int nx = 100;
int ny = 100;
int nz = 100;
int num_points = nx * ny * nz;
```
3. 创建网格点的坐标数组,并使用OpenMP并行计算。
```c++
vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New();
points->SetNumberOfPoints(num_points);
#pragma omp parallel for
for (int k = 0; k < nz; k++) {
for (int j = 0; j < ny; j++) {
for (int i = 0; i < nx; i++) {
double x = i / double(nx - 1);
double y = j / double(ny - 1);
double z = k / double(nz - 1);
int index = k * ny * nx + j * nx + i;
points->SetPoint(index, x, y, z);
}
}
}
```
4. 创建单元格数组,并使用OpenMP并行计算。
```c++
vtkSmartPointer<vtkCellArray> cells = vtkSmartPointer<vtkCellArray>::New();
cells->Allocate(num_points);
#pragma omp parallel for
for (int k = 0; k < nz - 1; k++) {
for (int j = 0; j < ny - 1; j++) {
for (int i = 0; i < nx - 1; i++) {
int id0 = k * ny * nx + j * nx + i;
int id1 = id0 + 1;
int id2 = id0 + nx;
int id3 = id2 + 1;
int id4 = id0 + nx * ny;
int id5 = id4 + 1;
int id6 = id4 + nx;
int id7 = id6 + 1;
vtkSmartPointer<vtkHexahedron> hex = vtkSmartPointer<vtkHexahedron>::New();
hex->GetPointIds()->SetId(0, id0);
hex->GetPointIds()->SetId(1, id1);
hex->GetPointIds()->SetId(2, id3);
hex->GetPointIds()->SetId(3, id2);
hex->GetPointIds()->SetId(4, id4);
hex->GetPointIds()->SetId(5, id5);
hex->GetPointIds()->SetId(6, id7);
hex->GetPointIds()->SetId(7, id6);
cells->InsertNextCell(hex);
}
}
}
```
5. 将网格数据写入文件。
```c++
vtkSmartPointer<vtkUnstructuredGrid> grid = vtkSmartPointer<vtkUnstructuredGrid>::New();
grid->SetPoints(points);
grid->SetCells(VTK_HEXAHEDRON, cells);
vtkSmartPointer<vtkXMLUnstructuredGridWriter> writer = vtkSmartPointer<vtkXMLUnstructuredGridWriter>::New();
writer->SetFileName("grid.vtu");
writer->SetInputData(grid);
writer->Write();
```
以上就是在VTK中使用OpenMP并行创建非结构化数据集的步骤,通过并行计算可以显著提高计算效率。