www.pudn.com > multiMonitor_demo.rar > MultiMonitor.cpp

// Monitor.cpp : implementation file 
// 
////////////////////////////////////////////////// 
// CMonitor - wrapper to Win32 multi-monitor API 
// 
// Author: Donald Kackman 
// Email:  don@itsEngineering.com 
// Copyright 2002, Donald Kackman 
// 
// You may freely use or modify this code provided this 
// Copyright is included in all derived versions. 
// 
/////////////////////////////////////////////////// 
 
 
#include "stdafx.h" 
#include "MultiMonitor.h" 
#include "Monitors.h" 
 
// CMonitor 
 
// constucts a monitor class not attached to any handle 
CMonitor::CMonitor() : m_hMonitor( NULL ) 
{	 
} 
 
// copy constructor 
CMonitor::CMonitor( const CMonitor& monitor  ) 
{ 
	m_hMonitor = (HMONITOR)monitor; 
} 
 
CMonitor::~CMonitor() 
{ 
} 
 
void CMonitor::Attach( const HMONITOR hMonitor ) 
{ 
	ASSERT( CMonitors::IsMonitor( hMonitor ) ); 
 
	m_hMonitor = hMonitor; 
} 
 
HMONITOR CMonitor::Detach()  
{ 
	HMONITOR hMonitor = m_hMonitor; 
	m_hMonitor = NULL; 
	return hMonitor; 
} 
 
// creates an HDC for the monitor 
// it is up to the client to call DeleteDC 
// 
// for normal multimonitor drawing it is not necessary to get a 
// dc for each monitor. Windows takes care of drawing correctly 
// on all monitors 
// 
// Only very exacting applications would need a DC for each monitor 
HDC CMonitor::CreateDC() const 
{ 
	ASSERT( IsMonitor() ); 
 
	CString name; 
	GetName( name ); 
 
	//create a dc for this display 
	HDC hdc = ::CreateDC( name, name, NULL, NULL ); 
	ASSERT( hdc != NULL ); 
 
	//set the viewport based on the monitor rect's relation to the primary monitor 
	CRect rect; 
	GetMonitorRect( &rect ); 
 
	::SetViewportOrgEx( hdc, -rect.left, -rect.top, NULL ); 
	::SetViewportExtEx( hdc, rect.Width(), rect.Height(), NULL ); 
 
	return hdc; 
} 
 
int CMonitor::GetBitsPerPixel() const 
{ 
	HDC hdc = CreateDC(); 
	int ret = ::GetDeviceCaps( hdc, BITSPIXEL ) * ::GetDeviceCaps( hdc, PLANES ); 
	VERIFY( ::DeleteDC( hdc ) ); 
 
	return ret; 
} 
 
void CMonitor::GetName( CString& string ) const 
{ 
	ASSERT( IsMonitor() ); 
 
	MONITORINFOEX mi; 
	mi.cbSize = sizeof( mi ); 
	::GetMonitorInfo( m_hMonitor, &mi ); 
 
	string = mi.szDevice; 
} 
 
// 
// these methods return true if any part of the item intersects the monitor rect 
BOOL CMonitor::IsOnMonitor( const POINT pt ) const 
{ 
	CRect rect; 
	GetMonitorRect( rect ); 
 
	return rect.PtInRect( pt ); 
} 
 
BOOL CMonitor::IsOnMonitor( const CWnd* pWnd ) const 
{ 
	CRect rect; 
	GetMonitorRect( rect ); 
 
	ASSERT( ::IsWindow( pWnd->GetSafeHwnd() ) ); 
	CRect wndRect; 
	pWnd->GetWindowRect( &wndRect ); 
 
	return rect.IntersectRect( rect, wndRect ); 
} 
 
BOOL CMonitor::IsOnMonitor( const LPRECT lprc ) const 
{ 
	CRect rect; 
	GetMonitorRect( rect ); 
 
	return rect.IntersectRect( rect, lprc ); 
} 
 
void CMonitor::GetMonitorRect( LPRECT lprc ) const 
{ 
	ASSERT( IsMonitor() ); 
	 
	MONITORINFO mi; 
    RECT        rc; 
 
	mi.cbSize = sizeof( mi ); 
	::GetMonitorInfo( m_hMonitor, &mi ); 
	rc = mi.rcMonitor; 
 
	::SetRect( lprc, rc.left, rc.top, rc.right, rc.bottom ); 
} 
 
// 
// the work area does not include the start bar 
void CMonitor::GetWorkAreaRect( LPRECT lprc ) const 
{ 
	ASSERT( IsMonitor() ); 
 
	MONITORINFO mi; 
    RECT        rc; 
 
	mi.cbSize = sizeof( mi ); 
	::GetMonitorInfo( m_hMonitor, &mi ); 
	rc = mi.rcWork; 
 
	::SetRect( lprc, rc.left, rc.top, rc.right, rc.bottom ); 
} 
 
//these two center methods are adapted from David Campbell's 
//MSJ article (see comment at the top of the header file) 
void CMonitor::CenterRectToMonitor( LPRECT lprc, const BOOL UseWorkAreaRect ) const 
{ 
    int  w = lprc->right - lprc->left; 
    int  h = lprc->bottom - lprc->top; 
 
    CRect rect; 
    if ( UseWorkAreaRect ) 
        GetWorkAreaRect( &rect ); 
    else 
        GetMonitorRect( &rect ); 
 
    lprc->left = rect.left + ( rect.Width() - w ) / 2; 
    lprc->top = rect.top + ( rect.Height() - h ) / 2; 
    lprc->right	= lprc->left + w; 
    lprc->bottom = lprc->top + h; 
} 
 
void CMonitor::CenterWindowToMonitor( CWnd* const pWnd, const BOOL UseWorkAreaRect ) const 
{ 
	ASSERT( IsMonitor() ); 
	ASSERT( pWnd ); 
	ASSERT( ::IsWindow( pWnd->m_hWnd ) ); 
 
	CRect rect; 
    pWnd->GetWindowRect( &rect ); 
    CenterRectToMonitor( &rect, UseWorkAreaRect ); 
    pWnd->SetWindowPos( NULL, rect.left, rect.top, 0, 0, SWP_NOSIZE | SWP_NOZORDER | SWP_NOACTIVATE ); 
} 
 
void CMonitor::ClipRectToMonitor( LPRECT lprc, const BOOL UseWorkAreaRect ) const 
{ 
    int w = lprc->right - lprc->left; 
    int h = lprc->bottom - lprc->top; 
 
    CRect rect; 
    if ( UseWorkAreaRect ) 
        GetWorkAreaRect( &rect ); 
    else 
        GetMonitorRect( &rect ); 
 
    lprc->left = max( rect.left, min( rect.right - w, lprc->left ) ); 
    lprc->top = max( rect.top, min( rect.bottom - h, lprc->top ) ); 
    lprc->right = lprc->left + w; 
    lprc->bottom = lprc->top  + h; 
} 
 
// 
// is the instance the primary monitor 
BOOL CMonitor::IsPrimaryMonitor() const 
{ 
	ASSERT( IsMonitor() ); 
 
	MONITORINFO mi; 
 
	mi.cbSize = sizeof( mi ); 
	::GetMonitorInfo( m_hMonitor, &mi ); 
	 
	return mi.dwFlags == MONITORINFOF_PRIMARY; 
} 
 
// 
// is the instance currently attached to a valid monitor handle 
BOOL CMonitor::IsMonitor() const  
{ 
	return CMonitors::IsMonitor( m_hMonitor ); 
}