VTK从CSV文件中读取数据

CSV也是一种文本文件，类似于TXT文本文件。但是由于CSV文件的特殊用途，本身可以由Excel办公软件获得，也有广泛的用途。以下示例演示采用C++方式读取CSV文件的点云数据，然后借助VTK可视化管线，渲染读取的点云数据。

#include <vtkSmartPointer.h>
#include <vtkSimplePointsReader.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkProperty.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
#include <vector>
#include <vtkVertexGlyphFilter.h>

using namespace std;
//删除字符串中空格，制表符tab等无效字符
string Trim(string& str)
{
	//str.find_first_not_of(" \t\r\n"),在字符串str中从索引0开始，返回首次不匹配"\t\r\n"的位置
	str.erase(0,str.find_first_not_of(" \t\r\n"));
	str.erase(str.find_last_not_of(" \t\r\n") + 1);
	return str;
}

int main( )
{
	vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New();
	double x,y,z;
	ifstream fin("Points.csv"); //打开文件流操作
	string line; 
	while (getline(fin, line))   //整行读取，换行符“\n”区分，遇到文件尾标志eof终止读取
	{
		//cout <<"原始字符串："<< line << endl; //整行输出
		istringstream sin(line); //将整行字符串line读入到字符串流istringstream中
		vector<string> fields; //声明一个字符串向量
		string field;
		while (getline(sin, field, ',')) //将字符串流sin中的字符读入到field字符串中，以逗号为分隔符
		{
			fields.push_back(field); //将刚刚读取的字符串添加到向量fields中
		}
		string sx = Trim(fields[0]); 
		string sy = Trim(fields[1]); 
		string sz = Trim(fields[2]); 
		//字符串转换成double型数字
		istringstream streamx,streamy,streamz;
		streamx.str(sx),streamy.str(sy),streamz.str(sz);
		streamx>>x,streamy>>y,streamz>>z;
		points->InsertNextPoint(x, y, z); //新读取的数据赋予点的几何结构  
	}
	fin.close();  //关闭文件
	vtkSmartPointer<vtkPolyData> polyData = vtkSmartPointer<vtkPolyData>::New();  
	polyData->SetPoints(points);

	vtkSmartPointer<vtkVertexGlyphFilter> glyphFilter =  vtkSmartPointer<vtkVertexGlyphFilter>::New();  
	#if VTK_MAJOR_VERSION <= 5  
	  glyphFilter->SetInputConnection(polyData->GetProducerPort());  
	#else  
	  glyphFilter->SetInputData(polyData);  
	#endif  
	  glyphFilter->Update(); 

	// Visualize
	vtkSmartPointer<vtkPolyDataMapper> mapper =  vtkSmartPointer<vtkPolyDataMapper>::New();
	mapper->SetInputConnection(glyphFilter->GetOutputPort());

	vtkSmartPointer<vtkActor> actor =  vtkSmartPointer<vtkActor>::New();
	actor->SetMapper(mapper);
	actor->GetProperty()->SetPointSize(4);
	actor->GetProperty()->SetColor(0.0,0.0,0.0);

	vtkSmartPointer<vtkRenderer> renderer =  vtkSmartPointer<vtkRenderer>::New();
	renderer->AddActor(actor);
	renderer->SetBackground(1.3, 1.6, 1.3); // Background color green

	vtkSmartPointer<vtkRenderWindow> renderWindow =  vtkSmartPointer<vtkRenderWindow>::New();
	renderWindow->AddRenderer(renderer);


	vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =  vtkSmartPointer<vtkRenderWindowInteractor>::New();
	renderWindowInteractor->SetRenderWindow(renderWindow);

	renderWindow->Render();
	renderWindowInteractor->Start();

	return EXIT_SUCCESS;
}

Excel文件中的点云数据如下图所示：

生成的CSV文件如下图所示：

读取Point.csv文件中的点云数据，并经由VTK可视化管线渲染之后的点云数据如下图所示，