请问导航图如何实现？（玩过红警的更容易解答）

Question

我用DDRAW作过，
代码丢了，
怀念啊

Answer 1

to  jiangsheng(蒋晟.Net):
   有一些道理，就算一样吧！那具体应该如何实现呢，描述一下就行了
我想知道个大概！多谢了哥们

Answer 2

void CEMapView::OnPrepareDC(CDC* pDC, CPrintInfo* pInfo) 
{
// TODO: Add your specialized code here and/or call the base class
CScrollView::OnPrepareDC(pDC, pInfo);
CEMapDoc* pDoc = GetDocument();
CSize sizeDoc = pDoc->GetSize();
CPoint ptOrg;
CRect rectClient;
GetClientRect(&rectClient);
pDC->DPtoLP(&rectClient);
ptOrg.x = min(-sizeDoc.cx / 2,-rectClient.Size().cx/2);
ptOrg.y = max(sizeDoc.cy / 2,-rectClient.Size().cy/2);
// ptOrg is in logical coordinates
pDC->SetWindowOrg(ptOrg);
}
void CEMapThumbnailView::OnPrepareDC(CDC* pDC, CPrintInfo* pInfo) 
{
// TODO: Add your specialized code here and/or call the base class
CEMapDoc* pDoc = GetDocument();
CSize sizeDoc=pDoc->GetSize();
CRect rectClient;
GetClientRect(&rectClient);
pDoc->PixelToLongEngish(&rectClient);
CView::OnPrepareDC(pDC, pInfo);
pDC->SetMapMode(MM_ANISOTROPIC);
CSize sizeView;
LONGLONG x1y2,x2y1;
x1y2=Int32x32To64(sizeDoc.cx,rectClient.Width());
x2y1=Int32x32To64(sizeDoc.cy,rectClient.Height());
if(x1y2>x2y1){//image is too wide,stretch y
sizeView.cx=::MulDiv(sizeDoc.cy,rectClient.Width(),rectClient.Height());
sizeView.cy=sizeDoc.cy;
}
else{//image is too thin,stretch x
sizeView.cx=sizeDoc.cx;
sizeView.cy=::MulDiv(sizeDoc.cx,rectClient.Height(),rectClient.Width());
}
GetClientRect(&rectClient);
pDC->SetWindowExt(sizeView);
pDC->SetViewportExt(rectClient.Width(),-rectClient.Height());
CPoint ptOrg;
ptOrg.x = -sizeView.cx/2;
ptOrg.y = sizeView.cy/2;
// ptOrg is in logical coordinates
pDC->SetWindowOrg(ptOrg.x,ptOrg.y);}
void CEMapThumbnailView::OnDraw(CDC* pDC)
{
CEMapDoc* pDoc = GetDocument();
// TODO: add draw code here
CRect rectMap=pDoc->GetMapRect() ;
pDoc->m_dibMapCurrent.Draw(*pDC,&rectMap);
if(pDoc->m_pEMapView->GetSafeHwnd()){
CRect rectViewPort;
pDoc->m_pEMapView->GetViewPort(&rectViewPort);
CSize sizeTotal=pDoc->m_pEMapView->GetTotalSize();
//rectViewPort.OffsetRect(sizeTotal.cx/2,sizeTotal.cy/2);
m_RectTracker.m_rect.left=MulDiv(rectViewPort.left,rectMap.Width(),sizeTotal.cx);
m_RectTracker.m_rect.right=MulDiv(rectViewPort.right,rectMap.Width(),sizeTotal.cx);
m_RectTracker.m_rect.top=-MulDiv(rectViewPort.bottom,rectMap.Height(),sizeTotal.cy);
m_RectTracker.m_rect.bottom=-MulDiv(rectViewPort.top,rectMap.Height(),sizeTotal.cy);
pDC->LPtoDP(m_RectTracker.m_rect);
m_RectTracker.Draw(pDC);
}
}
void CEMapView::GetViewPort(LPRECT lpRect)
{
GetClientRect(lpRect);
ClientToDoc(lpRect);
}