welllll when i run this program and when i scroll up it leaves lines that shouldnt be there and stuff..... i was wondering why does it keep doing this? heres the header file : class CMyApp : public CWinApp { public: virtual BOOL InitInstance (); }; class CMainWindow : public CFrameWnd { public: CMainWindow (); protected: int m_nViewWidth; // Workspace width in pixels int m_nViewHeight; // Workspace height in pixels int m_nHScrollPos; // Horizontal scroll position int m_nVScrollPos; // Vertical scroll position int m_nHPageSize; // Horizontal page size int m_nVPageSize; // Vertical page size protected: afx_msg void OnPaint (); afx_msg void OnSize (UINT nType, int cx, int cy); afx_msg void OnVScroll (UINT nCode, UINT nPos, CScrollBar* pScrollBar); afx_msg int OnCreate (LPCREATESTRUCT lpCreateStruct); DECLARE_MESSAGE_MAP () }; and heres the CPP file : #include <afxwin.h> #include "Hello.h" #include <math.h> CMyApp myApp; ///////////////////////////////////////////////////////////////////////// // CMyApp member functions BOOL CMyApp::InitInstance () { m_pMainWnd = new CMainWindow; m_pMainWnd->ShowWindow (m_nCmdShow); m_pMainWnd->UpdateWindow (); return TRUE; } ///////////////////////////////////////////////////////////////////////// // CMainWindow message map and member functions BEGIN_MESSAGE_MAP (CMainWindow, CFrameWnd) ON_WM_PAINT () ON_WM_VSCROLL () ON_WM_CREATE () ON_WM_SIZE () END_MESSAGE_MAP () CMainWindow::CMainWindow () { Create (NULL, _T ("The Hello Application"), WS_OVERLAPPEDWINDOW | WS_VSCROLL); } int CMainWindow::OnCreate (LPCREATESTRUCT lpCreateStruct) { CClientDC dc (this); m_nViewHeight = 101; return 0; } void CMainWindow::OnSize (UINT nType, int cx, int cy) { CFrameWnd::OnSize (nType, cx, cy); // // Set the vertical scrolling parameters. // int nVScrollMax = 0; m_nVPageSize = 0; nVScrollMax = 100; m_nVPageSize = 25; SCROLLINFO si; si.fMask = SIF_PAGE | SIF_RANGE | SIF_POS; si.nMin = 0; si.nMax = nVScrollMax; si.nPos = 0; si.nPage = m_nVPageSize; SetScrollInfo (SB_VERT, &si, TRUE); } void CMainWindow::OnVScroll (UINT nCode, UINT nPos, CScrollBar* pScrollBar) { int SCROLL=0; switch (nCode) { case SB_LINEUP: SCROLL = -5; break; case SB_LINEDOWN: SCROLL = 5; break; case SB_PAGEUP: SCROLL = -m_nVPageSize; break; case SB_THUMBTRACK: SCROLL = (int) nPos - m_nVScrollPos; break; case SB_PAGEDOWN: SCROLL = m_nVPageSize; break; default: // Ignore other scroll bar messages return; } int nScrollPos = m_nVScrollPos + SCROLL; int nMaxPos = m_nViewHeight - m_nVPageSize; if (nScrollPos < 0) SCROLL = -m_nVScrollPos; else if (nScrollPos > nMaxPos) SCROLL = nMaxPos - m_nVScrollPos; if (SCROLL != 0) { m_nVScrollPos += SCROLL; SetScrollPos (SB_VERT, m_nVScrollPos, TRUE); ScrollWindow (0, -SCROLL); } } void CMainWindow::OnPaint () { CPaintDC dc (this); dc.Rectangle(0,0,100,100); } and remember it needs to be run in a Win32 app. and include the MFC dll. :-D (visual c++) GIMPS

Disregard this thread :) I found out what the problem was, i needed to set the windows origin as it moved with the dc.SetWindowOrg (m_nHScrollPos, m_nVScrollPos); function in the OnPaint () message :) Now i just gotta explain what all the code does and post it up at www.planetsourcecode.com :) Also for anyone who learns form example this is a good site to go to, it has over 100,000,000 lines of code in like 14 different languages (programming) :) Thank you anyone who attempted to help me solve this problem. GIMPS