请问如何用C++画出函数的图像.

请问如何用C++画出函数的图像.
有一个函数y=1/(1+x*x);用C++应该怎样画出

可以直接调用CodeBlocks,MinGW,Win SDK
2.CodeBlocks可以创建 Win32 GUI Project
3.resource.h
#include <windows.h>
// ID of Main Dialog
#define DLG_MAIN 101
4.resource.rc
#include "resource.h"
DLG_MAIN DIALOGEX 6,5,194,106
CAPTION "Code::Blocks Template Dialog App"
FONT 8,"Tahoma"
5.main.cpp
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include<stdlib.h>
#include<string.h>
#include "resource.h"
HINSTANCE hInst;
BOOL CALLBACK DialogProc(HWND hwndDlg,UINT uMsg,WPARAM wParam,LPARAM lParam)
{
  HDC hDC; //定义指向设备描述表的句柄
  HBRUSH hBrush; //定义指向画刷的句柄
  HPEN hPen; //定义指向画笔的句柄
  PAINTSTRUCT PtStr; //定义指向包含绘图信息的结构体变量
  switch(uMsg)
  {
    case WM_PAINT:
     hDC=BeginPaint(hwndDlg,&PtStr);
     SetMapMode(hDC,MM_ANISOTROPIC); //设置映像模式
     //设置画笔.采用系统预定定义的黑色画笔
     hPen=(HPEN)GetStockObject(BLACK_PEN);
     //定义画刷,采用系统预定义的深灰色画刷
     hBrush=(HBRUSH)GetStockObject(DKGRAY_BRUSH);
     SelectObject(hDC,hBrush); //选择画刷
     SelectObject(hDC,hPen); //选择画笔
     RoundRect(hDC,50,120,100,200,15,15); //圆角矩形
     //定义画刷,采用系统预定义的亮灰色画刷
     hBrush=(HBRUSH)GetStockObject(LTGRAY_BRUSH);
     SelectObject(hDC,hBrush); //选择画刷
     Ellipse(hDC,150,50,200,150); //椭圆
     //定义画刷,采用系统预定义的虚画刷
     hBrush=(HBRUSH)GetStockObject(HOLLOW_BRUSH);
     SelectObject(hDC,hBrush); //选择画刷
     Pie(hDC,250,50,300,100,250,50,300,50); //饼形
     EndPaint(hwndDlg,&PtStr); //结束绘图
     return TRUE;
    case WM_INITDIALOG:
      return TRUE;
    case WM_CLOSE:
     EndDialog(hwndDlg,0);
     return TRUE;
  }
  return FALSE;
}
int APIENTRY WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance,LPSTR lpCmdLine,int nShowCmd)
{
  hInst = hInstance;
  // The user interface is a modal dialog box
  return DialogBox(hInstance,MAKEINTRESOURCE(DLG_MAIN),NULL,(DLGPROC)DialogProc);
}