rom/graphics/getgbuffers.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Graphics function GetGBuffers()
   6     Lang: english
   7 */
   8 #include <graphics/gels.h>
   9 #include <graphics/rastport.h>
  10 #include "graphics_intern.h"
  11
  12 /*****************************************************************************
  13
  14     NAME */
  15 #include <proto/graphics.h>
  16
  17         AROS_LH3(BOOL, GetGBuffers,
  18
  19 /*  SYNOPSIS */
  20         AROS_LHA(struct AnimOb *, anOb, A0),
  21         AROS_LHA(struct RastPort *, rp, A1),
  22         AROS_LHA(BOOL , db, D0),
  23
  24 /*  LOCATION */
  25         struct GfxBase *, GfxBase, 28, Graphics)
  26
  27 /*  FUNCTION
  28         Allocate all buffers for a whole AnimOb. In particular this
  29         means getting buffers for
  30         - BorderLine
  31         - SaveBuffer
  32         - CollMask
  33         - ImageShadow (points to the same memory as CollMask does)
  34         - if db is set to TRUE the user wants double-buffering, so we need
  35           - DBufPacket
  36           - BufBuffer
  37
  38     INPUTS
  39         anOb = pointer to AnimOb structure to be added to list of
  40                AnimObs
  41         rp   = pointer to a valid RastPort with initialized GelsInfo
  42                structure
  43         db   = TRUE when double-buffering is wanted
  44
  45     RESULT
  46         TRUE, if all the memory allocations were successful, otherwise
  47         FALSE
  48
  49     NOTES
  50         If an AnimOb is passed to GetGBuffers twice new buffers will
  51         be allocated and therefore old pointers to buffers will be
  52         lost in space.
  53
  54     EXAMPLE
  55
  56     BUGS
  57
  58     SEE ALSO
  59         FreeGBuffers() graphics/gels.h
  60
  61     INTERNALS
  62         Are real VSprites possible as a part of an AnimOb?
  63         If yes, then different sizes of memory would have to be
  64         allocated for BorderLine and CollMask. Currently the
  65         sizes of memory allocated for this are most of the time
  66         too large as they are just allocated for a Bob. If this
  67         code is changed then the code of FreeGBuffers() will
  68         have to be changed, too, and this text can be erased :-))
  69
  70     HISTORY
  71
  72 *****************************************************************************/
  73 {
  74   AROS_LIBFUNC_INIT
  75   AROS_LIBBASE_EXT_DECL(struct GfxBase *,GfxBase)
  76
  77   struct AnimComp * CurAnimComp = anOb -> HeadComp;
  78
  79   /* visit all the components of this AnimOb */
  80   while (NULL != CurAnimComp)
  81   {
  82     /* visit all the sequences of a component
  83        the sequences are connected like a ring!! */
  84     struct AnimComp * CurSeqAnimComp = CurAnimComp;
  85     do
  86     {
  87       struct Bob * CurBob = CurSeqAnimComp -> AnimBob;
  88       struct VSprite * CurVSprite = CurBob -> BobVSprite;
  89       long memsize;
  90
  91       /* Attention: width of a Bob/VSprite is the number of *words* it
  92          uses for it's width */
  93
  94
  95       /* allocate height*(width*2) bytes of Chip-Ram for the ImageShadow */
  96       memsize =  (CurVSprite -> Height) *
  97                  (CurVSprite -> Width) * 2;
  98       if (NULL ==(CurBob -> ImageShadow = AllocMem(memsize, MEMF_CHIP|MEMF_CLEAR)))
  99         return FALSE;
 100
 101       /* CollMask points to the same memory as ImageShadow */
 102       CurVSprite -> CollMask = CurBob -> ImageShadow;
 103
 104       /* allocate height*(width*2)*depth bytes of Chip-Ram for
 105          the SaveBuffer */
 106       memsize *= (CurVSprite -> Depth);
 107       if (NULL ==(CurBob -> SaveBuffer =  AllocMem(memsize, MEMF_CHIP|MEMF_CLEAR)))
 108         return FALSE;
 109
 110
 111       /* allocate width*2 bytes = width words for BorderLine
 112        * !!! this is more than enough for VSprites as for a real VSprite
 113        * its size in pixels is given in CurVSprite->Width
 114        */
 115       if (NULL ==(CurVSprite -> BorderLine = AllocMem(CurVSprite -> Width * 2,
 116                                                       MEMF_CHIP|MEMF_CLEAR)))
 117         return FALSE;
 118
 119       /* are we using double buffering for this AnimOb? */
 120       if (TRUE == db)
 121       {
 122         /* allocate a DBufPacket structure */
 123         if (NULL ==(CurBob -> DBuffer = AllocMem(sizeof(struct DBufPacket),
 124                                                  MEMF_CLEAR)))
 125           return FALSE;
 126
 127         /* BufBuffer needs as much memory as SaveBuffer */
 128         /* memsize still contains the size of memory required for SaveBuffer */
 129         if (NULL ==(CurBob -> DBuffer -> BufBuffer =
 130                     AllocMem(memsize, MEMF_CHIP|MEMF_CLEAR)))
 131           return FALSE;
 132       }
 133
 134       /* go to the next sequence of this component */
 135       CurSeqAnimComp = CurSeqAnimComp -> NextSeq;
 136     }
 137     while (CurAnimComp != CurSeqAnimComp);
 138
 139     /* go to next component */
 140     CurAnimComp = CurAnimComp -> NextComp;
 141   }
 142   /* all allocations went OK */
 143   return TRUE;
 144
 145   AROS_LIBFUNC_EXIT
 146 } /* GetGBuffers */