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Drawing bitmap on window - how to clear window/HDC?

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Join Date: Sep 2004

Posts: 55

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apcxpc

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Drawing bitmap on window - how to clear window/HDC?

Feb 27th, 2006

Hi all

My program currently loads a bitmap (given a filename) and draws it to a window (win32 application).

The problem is that once a different bitmap is loaded and drawn to the window... if the new bitmap is smaller than the old bitmap, the edges of the old bitmap are still visible once the new bitmap is drawn.
I need a way to completely clear the window before drawing each new bitmap. ... How do I do this??

Here is where I paint the window...

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Help with Code Tags

C Syntax (Toggle Plain Text)
LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)                
    {
      case WM_PAINT:
        {
              HDC hDC = GetDC(hwnd);
              if (cd->GetFilename() != NULL) cd ->DrawBits(hDC,0,0);
              ReleaseDC(hwnd, hDC);
              break;
         }
        //handle other messages
       }
}
LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) { switch (message) { case WM_PAINT: { HDC hDC = GetDC(hwnd); if (cd->GetFilename() != NULL) cd ->DrawBits(hDC,0,0); ReleaseDC(hwnd, hDC); break; } //handle other messages } }