picture.cpp

一个简单的vc++开发的城市公交地图编辑器源代码及生成的地图样例

////////////////////////////////////////////////////////////////
// MSDN Magazine -- October 2001
// If this code works, it was written by Paul DiLascia.
// If not, I don't know who wrote it.
// Compiles with Visual C++ 6.0 for Windows 98 and probably Windows 2000 too.
// Set tabsize = 3 in your editor.
//
#include "StdAfx.h"
#include "Picture.h"

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

////////////////////////////////////////////////////////////////
// CPicture implementation
//

CPicture::CPicture()
{
}

CPicture::~CPicture()
{
	if(this->m_spIPicture) Free();
}

//////////////////
// Load from resource. Looks for "IMAGE" type.
//
BOOL CPicture::Load(UINT nIDRes,LPCTSTR resType)
{
	// find resource in resource file
	return Load(MAKEINTRESOURCE(nIDRes),resType); 

}

//////////////////
// Load from path name.
//
BOOL CPicture::Load(LPCTSTR pszPathName)
{
	CFile file;
	if (!file.Open(pszPathName, CFile::modeRead|CFile::shareDenyWrite))
		return FALSE;
	BOOL bRet = Load(file);
	file.Close();
	return bRet;
}

//////////////////
// Load from CFile
//
BOOL CPicture::Load(CFile& file)
{
	DWORD dwSize=file.GetLength();
	HGLOBAL hglobal=GlobalAlloc(GMEM_MOVEABLE | GMEM_NODISCARD,dwSize);
	BYTE *buffer=reinterpret_cast<BYTE*>(GlobalLock(hglobal));;
	file.SeekToBegin();
	file.ReadHuge(buffer,dwSize);
	BOOL hr=Load(hglobal,dwSize);
	GlobalUnlock(hglobal);
	GlobalFree(hglobal);
	return hr;
}

///////////////////
// load from buffer
///////////////////
BOOL CPicture::Load(HGLOBAL hGlobal, DWORD buflen)
{
	IStream *istm=NULL;
	if (CreateStreamOnHGlobal(hGlobal,FALSE,&istm) != S_OK)
			return FALSE;
	BOOL bRet = Load(istm);
	istm->Release();
	return bRet;
}


//////////////////
// Load from stream (IStream). This is the one that really does it: call
// OleLoadPicture to do the work.
//
BOOL CPicture::Load(IStream* pstm)
{
	Free();
	HRESULT hr = OleLoadPicture(pstm, 0, FALSE,
		IID_IPicture, (void**)&m_spIPicture);
	return (SUCCEEDED(hr) && m_spIPicture);	
}

//////////////////
// Render to device context. Covert to HIMETRIC for IPicture.
//
BOOL CPicture::Render(CDC* pDC, CRect rc,int zoomtype) const
{
	ASSERT(pDC);
	CSize sz = GetImageSize(pDC);

	if (rc.IsRectNull()) {
		rc.right = sz.cx;
		rc.bottom = sz.cy;
	}
	long hmWidth,hmHeight; // HIMETRIC units
	GetHIMETRICSize(hmWidth, hmHeight);
	int wid,hei;
	CRect rect=rc;
	switch(zoomtype)
	{
	case 0:
		rect.left=rc.left+(rc.Width()-sz.cx)/2;
		rect.right=rc.right-(rc.Width()-sz.cx)/2;
		rect.top=rc.top+(rc.Height()-sz.cy)/2;
		rect.bottom =rc.bottom -(rc.Height()-sz.cy)/2;
		break;
	case 1:
		wid=rc.Width(),hei=hmHeight*wid/hmWidth;
		if(hei>rc.Height())	hei=rc.Height(),wid=hmWidth*hei/hmHeight;
		if(wid==rc.Width())	rect.SetRect(rc.left,rc.top+(rc.Height()-hei)/2,rc.right,rc.bottom-(rc.Height()-hei)/2);
		else rect.SetRect(rc.left+(rc.Width()-wid)/2,rc.top,rc.right-(rc.Width()-wid)/2,rc.bottom);
		break;
	default:
		break;
	}
	m_spIPicture->Render(*pDC, rect.left, rect.top, rect.Width(), rect.Height(),
		0, hmHeight, hmWidth, -hmHeight, NULL);

	return TRUE;
}

//////////////////
// Get image size in pixels. Converts from HIMETRIC to device coords.
//
CSize CPicture::GetImageSize(CDC* pDC) const
{
	if (!m_spIPicture)
		return CSize(0,0);
	
	LONG hmWidth, hmHeight; // HIMETRIC units
	m_spIPicture->get_Width(&hmWidth);
	m_spIPicture->get_Height(&hmHeight);
	CSize sz(hmWidth,hmHeight);
	if (pDC==NULL) {
		CWindowDC dc(NULL);
		dc.HIMETRICtoDP(&sz); // convert to pixels
	} else {
		pDC->HIMETRICtoDP(&sz);
	}
	return sz;
}




BOOL CPicture::Load(LPCTSTR resstr, LPCTSTR restype)
{
	HINSTANCE hInst = AfxGetResourceHandle();
	HRSRC hRsrc = ::FindResource(hInst,
		resstr,
		restype); // type
	if (!hRsrc)
		return FALSE;

	// load resource into memory
	DWORD len = SizeofResource(hInst, hRsrc);
	BYTE* lpRsrc = (BYTE*)LoadResource(hInst, hRsrc);
	if (!lpRsrc)
		return FALSE;

	// create memory file and load it
	CMemFile file(lpRsrc, len);
	BOOL bRet = Load(file);
	FreeResource(hRsrc);
	GlobalFree(lpRsrc);
	return bRet;
}

BOOL CPicture::Render(CDC *pDC,
					  int x, int y,int nWidth, int nHeight,
					  int xSrc, int ySrc, int nSrcWidth, int nSrcHeight)
{
	CSize lefttop,rightbottom;
	lefttop.cx=xSrc,lefttop.cy=ySrc;
	rightbottom.cx=nSrcWidth,rightbottom.cy=nSrcHeight;
	pDC->DPtoHIMETRIC(&lefttop);
	pDC->DPtoHIMETRIC(&rightbottom);
	LONG hmWidth, hmHeight; // HIMETRIC units
	m_spIPicture->get_Width(&hmWidth);
	m_spIPicture->get_Height(&hmHeight);
	m_spIPicture->Render(*pDC, x,y, nWidth,nHeight,lefttop.cx, hmHeight-lefttop.cy, rightbottom.cx, -rightbottom.cy, NULL);
	return TRUE;
}