Don Kackman Multiple Monitors Classes Port to WTL

// Monitor.h : implementation of the CMonitor class
//
/////////////////////////////////////////////////////////////////////////////

// David Campbell's article "How to Exploit Multiple Monitor Support in Memphis and Windows NT 5.0"
// is very helpful for multimonitor api calls
// http://www.microsoft.com/msj/defaultframe.asp?page=/msj/0697/monitor/monitor.htm&nav=/msj/0697/newnav.htm

// 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.
//
// Ported to WTL by Igor Vigdorchik

#include "stdafx.h"
#include "Monitor.h"
#include "Monitors.h"

CMonitor::CMonitor() : m_hMonitor(NULL) {}

CMonitor::CMonitor(const CMonitor& monitor)
{
	m_hMonitor = (HMONITOR)monitor;
}

void CMonitor::Attach(const HMONITOR hMonitor)
{
	ATLASSERT(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
{
	ATLASSERT(IsMonitor());

	CString name;
	GetName(name);

	// Create a dc for this display
	HDC hdc = ::CreateDC(name, name, NULL, NULL);
	ATLASSERT(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;
}

void CMonitor::ClipRectToMonitor(LPRECT lprc, const BOOL bUseWorkAreaRect) const
{
	// The work area is the monitor rect minus the start bar
	int w = lprc->right - lprc->left;
	int h = lprc->bottom - lprc->top;

	CRect rect;
	if (bUseWorkAreaRect)
		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;
}

// 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 bUseWorkAreaRect) const
{
	// The work area is the monitor rect minus the start bar
	int  w = lprc->right - lprc->left;
	int  h = lprc->bottom - lprc->top;

	CRect rect;
	if (bUseWorkAreaRect)
		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(CWindow* const pWnd, const BOOL bUseWorkAreaRect) const
{
	// The work area is the monitor rect minus the start bar
	ATLASSERT(IsMonitor());
	ATLASSERT(pWnd);
	ATLASSERT(::IsWindow(pWnd->m_hWnd));

	CRect rect;
	pWnd->GetWindowRect(&rect);
	CenterRectToMonitor(&rect, bUseWorkAreaRect);
	pWnd->SetWindowPos(NULL, rect.left, rect.top, 0, 0, SWP_NOSIZE | SWP_NOZORDER | SWP_NOACTIVATE);
}

void CMonitor::GetMonitorRect(LPRECT lprc) const
{
	ATLASSERT(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);
}

void CMonitor::GetWorkAreaRect(LPRECT lprc) const
{
	ATLASSERT(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);
}

void CMonitor::GetName(CString& string) const
{
	ATLASSERT(IsMonitor());

	MONITORINFOEX mi;
	mi.cbSize = sizeof(mi);
	::GetMonitorInfo(m_hMonitor, &mi);

	string = mi.szDevice;
}

int CMonitor::GetBitsPerPixel() const
{
	HDC hdc = CreateDC();
	int ret = ::GetDeviceCaps(hdc, BITSPIXEL) * ::GetDeviceCaps(hdc, PLANES);
	::DeleteDC(hdc);

	return ret;
}

// Determines if the specified item on the monitor, 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 CWindow* pWnd) const
{
	CRect rect;
	GetMonitorRect(rect);

	ATLASSERT(::IsWindow(pWnd->m_hWnd));
	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);
}

// Is the instance the primary monitor
BOOL CMonitor::IsPrimaryMonitor() const
{
	ATLASSERT(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);
}