www.pudn.com > FIRDsgn.rar > DrawMag.cpp

//######################################################################## 
// This program is provided "as is" without any express  
// or implied warranty of any kind with respect to this software.  
// In particular the author shall not be liable for any direct,  
// indirect, special, incidental or consequential damages arising  
// in any way from use of the software. 
// 
// 
// Author   : Jialong He,  
// Date     : July, 1999.  
// 
// Contact  : Jialong_He@bigfoot.com, Jialong_He@homemail.com 
// Web Page : www.bigfoot.com/~Jialong_He 
//######################################################################## 
// DrawMag.cpp : implementation file 
// 
 
#include "stdafx.h" 
#include "FIRDsgn.h" 
#include "DrawMag.h" 
#include  
#define FFTSize 1024 
 
#ifdef _DEBUG 
#define new DEBUG_NEW 
#undef THIS_FILE 
static char THIS_FILE[] = __FILE__; 
#endif 
 
///////////////////////////////////////////////////////////////////////////// 
// CDrawMag 
 
CDrawMag::CDrawMag() 
{ 
 
	m_BrushBlack.lbStyle = BS_SOLID; 
	m_BrushBlack.lbColor = RGB(0, 0, 0); 
	m_BrushBlack.lbHatch = 0; 
 
	m_BrushCross.lbStyle = BS_HATCHED; 
	m_BrushCross.lbColor = RGB(0, 255, 0); 
	m_BrushCross.lbHatch = HS_CROSS; 
 
	MagArr = NULL; 
	MagLen = 0;               
 
} 
 
CDrawMag::~CDrawMag() 
{ 
	delete [] MagArr; 
} 
 
 
BEGIN_MESSAGE_MAP(CDrawMag, CWnd) 
	//{{AFX_MSG_MAP(CDrawMag) 
	ON_WM_PAINT() 
	//}}AFX_MSG_MAP 
END_MESSAGE_MAP() 
 
 
///////////////////////////////////////////////////////////////////////////// 
// CDrawMag message handlers 
 
 
void CDrawMag::OnPaint()  
{ 
	CPaintDC dc(this); // device context for painting 
	 
	CRect rect; 
	 
	dc.SetPolyFillMode(WINDING); 
 
	CBrush brushBlack(m_BrushBlack.lbColor); 
//	CBrush brushCross(HS_CROSS, RGB(0, 0, 0)); 
	GetClientRect(rect); 
 
	dc.FillRect(&rect, &brushBlack); 
	 
//	dc.SelectObject(&brushCross); 
//	dc.Rectangle(rect); 
 
	//------------------------------ 
	// draw grid in green color 
	//------------------------------ 
	int x, y, xstep, ystep; 
	int H = rect.Height(); 
	int W = rect.Width(); 
	CPen GreenPen(PS_DOT, 1, RGB(0, 255, 0)); 
	dc.SelectObject(&GreenPen); 
	 
	xstep = W / 10; 
	for (x=0; xreal = wrecur_real; 
            xj->imag = wrecur_imag; 
            xj++; 
            wtemp_real = wrecur_real*w_real - wrecur_imag*w_imag; 
            wrecur_imag = wrecur_real*w_imag + wrecur_imag*w_real; 
            wrecur_real = wtemp_real; 
        } 
    } 
 
	/* start fft */ 
 
    le = n; 
    windex = 1; 
    for (l = 0 ; l < m ; l++) { 
        le = le/2; 
 
	/* first iteration with no multiplies */ 
 
        for(i = 0 ; i < n ; i = i + 2*le) { 
            xi = x + i; 
            xip = xi + le; 
            temp.real = xi->real + xip->real; 
            temp.imag = xi->imag + xip->imag; 
            xip->real = xi->real - xip->real; 
            xip->imag = xi->imag - xip->imag; 
            *xi = temp; 
        } 
 
	/* remaining iterations use stored w */ 
 
        wptr = w + windex - 1; 
        for (j = 1 ; j < le ; j++) { 
            u = *wptr; 
            for (i = j ; i < n ; i = i + 2*le) { 
                xi = x + i; 
                xip = xi + le; 
                temp.real = xi->real + xip->real; 
                temp.imag = xi->imag + xip->imag; 
                tm.real = xi->real - xip->real; 
                tm.imag = xi->imag - xip->imag;              
                xip->real = tm.real*u.real - tm.imag*u.imag; 
                xip->imag = tm.real*u.imag + tm.imag*u.real; 
                *xi = temp; 
            } 
            wptr = wptr + windex; 
        } 
        windex = 2*windex; 
    }             
 
	/* rearrange data by bit reversing */ 
 
    j = 0; 
    for (i = 1 ; i < (n-1) ; i++) { 
        k = n/2; 
        while(k <= j) { 
            j = j - k; 
            k = k/2; 
        } 
        j = j + k; 
        if (i < j) { 
            xi = x + i; 
            xj = x + j; 
            temp = *xj; 
            *xj = *xi; 
            *xi = temp; 
        } 
    } 
 
    return (0); 
 
} 
 
//==================================================== 
//  calculate impulse response of FIR filter 
//==================================================== 
int CDrawMag::imp_response(double *FCoef, int FNum) { 
 
	COMPLEX *Sig; 
	int Cnt, RtCode; 
 
	if (FNum > FFTSize ) { 
		return(-1); // error 
	} 
 
	Sig    = new COMPLEX[FFTSize]; 
	if (Sig == NULL) { 
		return(-1); // error 
	} 
 
	//--------------------------- 
	// copy coefficients to Sig 
	//--------------------------- 
	for (Cnt=0; Cnt