rom/intuition/changescreenbuffer.c

   1 /*
   2     Copyright © 1995-2011, The AROS Development Team. All rights reserved.
   3     Copyright © 2001-2003, The MorphOS Development Team. All Rights Reserved.
   4     $Id$
   5 */
   6
   7 #include <proto/graphics.h>
   8 #include "intuition_intern.h"
   9 #include "inputhandler.h"
  10 #include "menus.h"
  11
  12 /*****************************************************************************
  13
  14     NAME */
  15 #include <intuition/screens.h>
  16 #include <proto/intuition.h>
  17
  18     AROS_LH2(ULONG, ChangeScreenBuffer,
  19
  20 /*  SYNOPSIS */
  21          AROS_LHA(struct Screen *      , screen, A0),
  22          AROS_LHA(struct ScreenBuffer *, screenbuffer, A1),
  23
  24 /*  LOCATION */
  25          struct IntuitionBase *, IntuitionBase, 130, Intuition)
  26
  27 /*  FUNCTION
  28     Do double or multiple buffering on an intuition screen in an
  29     intuition-cooperative way.
  30     The ScreenBuffer's BitMap will be installed on the specifies screen,
  31     if possible.
  32     After a signal from graphics.library, the previously installed
  33     BitMap will be available for re-use.
  34     Consult graphics.library/AllocDBufInfo() and
  35     graphics.library/ChangeVPBitMap() for further information.
  36
  37     INPUTS
  38     screen - The screen this screenbuffer belongs to
  39     screenbuffer - The screenbuffer obtained by AllocScreenBuffer()
  40
  41     RESULT
  42     Non-zero if fuction succeeded, or zero if operation could not be
  43     performed, eg. if user selects menus or gadgets.
  44
  45     NOTES
  46     You need not re-install the original ScreenBuffer before closing
  47     a screen. Just FreeScreenBuffer() all buffers used for that screen.
  48
  49     EXAMPLE
  50
  51     BUGS
  52
  53     SEE ALSO
  54     AllocScreenBuffer(), FreeScreenBuffer(),
  55     graphics.library/ChangeVPBitMap()
  56
  57     INTERNALS
  58
  59     HISTORY
  60
  61 *****************************************************************************/
  62 {
  63     AROS_LIBFUNC_INIT
  64
  65     struct GfxBase *GfxBase = GetPrivIBase(IntuitionBase)->GfxBase;
  66     struct IIHData   *iihdata;
  67     ULONG             lock;
  68
  69     if (!screen) return 0;
  70     if (!screenbuffer) return 0;
  71
  72     if (MENUS_ACTIVE) return 0;
  73     iihdata = (struct IIHData *)((struct IntIntuitionBase *)(IntuitionBase))->InputHandler->is_Data;
  74     if (iihdata->ActiveGadget) return 0;
  75
  76     ChangeVPBitMap(&screen->ViewPort,screenbuffer->sb_BitMap,screenbuffer->sb_DBufInfo);
  77
  78     lock = LockIBase(0);
  79
  80     screen->BitMap = *screenbuffer->sb_BitMap;
  81     screen->RastPort.BitMap = screenbuffer->sb_BitMap;
  82
  83     UnlockIBase(lock);
  84
  85     return TRUE;
  86
  87     AROS_LIBFUNC_EXIT
  88 } /* ChangeScreenBuffer */