OpenEuphoria

Rather than repainting the image on just part of your window, create a small child window the size of the image you want to display. That small window will receive its own paint events and will "clip" properly.

include Win32Lib.ew
without warning 
 
constant Main   = create( Window, "Test", 0, Default, Default, 640, 480, 0 ) 
constant PicWin = create( Window, "", Main, 10, 10, 64, 64, {WS_CHILD,WS_VISIBLE} ) 
 
procedure PicWin_onPaint( integer pSelf, integer pEvent, sequence pParams ) 
 
    copyBlt( PicWin, 0, 0, YourImage ) 
 
end procedure 
setHandler( PicWin, w32HPaint, routine_id("PicWin_onPaint") ) 
 
WinMain( Main, Normal )

Also, you may need to use transBlt() instead of copyBlt() if you need to preserve the transparent background of your image.

-Greg