memdc.h

多机器人合作中的动态角色分配仿真算法是多机器人合作领域的一个比较著名的仿真软件

#ifndef _MEMDC_H_
#define _MEMDC_H_

//////////////////////////////////////////////////
// CMemDC - memory DC
//
// Author: Keith Rule
// Email:  [e-mail]
// Copyright 1996-1997, Keith Rule
//
// You may freely use or modify this code provided this
// Copyright is included in all derived versions.
//
// History - 10/3/97 Fixed scrolling bug.
//                   Added print support.
//
// This class implements a memory Device Context

class CMemDC : public CDC {
private:
	CBitmap* m_oldBitmap; // bitmap originally found in CMemDC
	CDC* m_pDC; // Saves CDC passed in constructor
	CRect m_rect; // Rectangle of drawing area.
	BOOL m_bMemDC; // TRUE if CDC really is a Memory DC.
public:
	CBitmap m_bitmap; // Offscreen bitmap
	CMemDC(CDC* pDC, const CRect& rcBounds) : CDC(), m_oldBitmap(NULL), m_pDC(pDC)
	{
		ASSERT(m_pDC != NULL); // If you asserted here, you passed in a NULL CDC.
		
		m_bMemDC = !pDC->IsPrinting();
		

		if (m_bMemDC){
			// Create a Memory DC
			CreateCompatibleDC(pDC);
			pDC->GetClipBox(&m_rect);
			m_bitmap.CreateCompatibleBitmap(pDC, m_rect.Width(), m_rect.Height());
			m_oldBitmap = SelectObject(&m_bitmap);
			SetWindowOrg(m_rect.left, m_rect.top);

			//CBrush *bkg = new CBrush(RGB(255,255,255));
			//FillRect(m_rect, bkg);
			PatBlt(m_rect.left, m_rect.top, m_rect.Width(), m_rect.Height(), WHITENESS);

			//delete(bkg);
		} else {
			// Make a copy of the relevent parts of the current DC for printing
			m_bPrinting = pDC->m_bPrinting;
			m_hDC = pDC->m_hDC;
			m_hAttribDC = pDC->m_hAttribDC;
		}
	}
	
	~CMemDC()
	{
		if (m_bMemDC) {
			// Copy the offscreen bitmap onto the screen.
			m_pDC->BitBlt(m_rect.left, m_rect.top, m_rect.Width(), m_rect.Height(),
				this, m_rect.left, m_rect.top, SRCCOPY);
			//Swap back the original bitmap.
			SelectObject(m_oldBitmap);
		} else {
			// All we need to do is replace the DC with an illegal value,
			// this keeps us from accidently deleting the handles associated with
			// the CDC that was passed to the constructor.
			m_hDC = m_hAttribDC = NULL;
		}
	}


	CMemDC(CDC* pDC, CBitmap* pBmp)
	{
		// This	is the device context constructor, used	for	normal device contexts
		// crFill =	color to fill background with
		// pBmp	- bitmap to	be drawn to

		ASSERT_VALID(pDC);
		m_pDC =	pDC;
		m_oldBitmap =	NULL;

		// Memory DC is	we're not printing
		m_bMemDC = !pDC->IsPrinting();

		if (m_bMemDC)
		{
			// Step	1 -	Create a Memory	DC
			CreateCompatibleDC(pDC);

			// Step	2 -	Get	the	clip area 
			pDC->GetClipBox(&m_rect);
			pDC->LPtoDP(&m_rect);

			// BITMAP CASE 1: User passed bitmap, use it
			if (pBmp !=	NULL)
				m_oldBitmap =	SelectObject(pBmp);
			// BITMAP CASE 2: Create our own bitmap
			else
			{
				m_bitmap.CreateCompatibleBitmap(pDC, m_rect.Width(),	m_rect.Height());
				m_oldBitmap =	SelectObject(&m_bitmap);
			}

			SetMapMode(pDC->GetMapMode());
			pDC->DPtoLP(&m_rect);

			SetWindowOrg(m_rect.left,	m_rect.top);

			// Step	3 -	"Erase"	the	background using passed	color

			PatBlt(m_rect.left, m_rect.top,	m_rect.Width(), m_rect.Height(), WHITENESS);
		}
		else
		{
			// Make	a copy of the relevent parts of	the	current	DC for printing
			m_bPrinting	= pDC->m_bPrinting;
			m_hDC =	pDC->m_hDC;
			m_hAttribDC	= pDC->m_hAttribDC;
		}
	}
	
	// Allow usage as a pointer
	CMemDC* operator->() {return this;}
	
	// Allow usage as a pointer
	operator CMemDC*() {return this;}
};

#endif