image.cpp

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/***********************************************************************************
@author  Chandar
@version 1.0
Development Environment        :  Visual C++ 6.0
Name of the File               :  Image.cpp
Creation/Modification History  :
                                  01-Aug-2001     Created

Overview of file

  This file implements the CImage class to open the image file and store the data
  into LPPICTURE struct variable and to draw or display the image on the dialog 
  box
***********************************************************************************/


#include "stdafx.h"
#include "ADODBHandler.h"
#include "Image.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

#define HIMETRIC_INCH 2540


/**********************
Constructor definition
***********************/
CImage::CImage()
{
	gpPicture = NULL;
}


/**********************
Destructor definition
***********************/
CImage::~CImage()
{
	if(gpPicture != NULL)
		gpPicture->Release();	
}


/*********************************************************************
This function is used to draw the image using the device context object
passed to it in the area passed to it through CRect parameter
*********************************************************************/
BOOL CImage::DrawImage(CDC*pDC, CRect rectImage)
{
	//if device context is not valid or gpPicture is null, return from function
    if (pDC == NULL || gpPicture == NULL)
        return FALSE;
    
	
    long hmWidth  = 0;
    long hmHeight = 0;
    
	//get the height and width of picture
    gpPicture->get_Width (&hmWidth);
    gpPicture->get_Height(&hmHeight);

    
    HRESULT hr = NULL;
    
	//Draw the picture
    hr = gpPicture->Render(pDC->m_hDC,
                      rectImage.left,
                      rectImage.top,
                      rectImage.Width(),
                      rectImage.Height(),
                      0,
                      hmHeight,
                      hmWidth,
                      -hmHeight,
                      &rectImage);

    

    if (SUCCEEDED(hr))
        return TRUE;      //return true if successful

    return FALSE;
}

/**********************************************************************
This function takes the image file name as parameter and loads it in the
LPPICTURE struct variable which is used for drawing the image
***********************************************************************/ 
BOOL CImage::Open(_bstr_t strFile)
{
	
    if (gpPicture)
		(gpPicture)->Release();  //if gpPicture is not null , Release it

	//Load the picture data into the gpPicture 
	HRESULT hr=::OleLoadPicturePath(strFile, 0, 0, 0, IID_IPicture, (LPVOID*)&gpPicture);
	
	if (!(SUCCEEDED(hr)))
    {
        //Show message if failed to load the image
        AfxMessageBox("Could not load image "+strFile);
        return FALSE;
    }
    
    return TRUE;  //Made it ...!
}