rom/graphics/initmasks.c

   1 /*
   2     Copyright © 1995-2007, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Graphics function InitMasks()
   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_LH1(void, InitMasks,
  18
  19 /*  SYNOPSIS */
  20         AROS_LHA(struct VSprite *, vs, A0),
  21
  22 /*  LOCATION */
  23         struct GfxBase *, GfxBase, 21, Graphics)
  24
  25 /*  FUNCTION
  26         Creates the standard BorderLine and CollMask masks of the VSprite.
  27         VSprites and Bobs are treated accordingly.
  28
  29     INPUTS
  30         vs = pointer to VSprite structure
  31
  32     RESULT
  33
  34     NOTES
  35
  36     EXAMPLE
  37
  38     BUGS
  39
  40     SEE ALSO
  41         InitGels(), InitGMasks(), graphics/gels.h
  42
  43     INTERNALS
  44
  45     HISTORY
  46
  47 *****************************************************************************/
  48 {
  49   AROS_LIBFUNC_INIT
  50
  51   LONG depth, WordsPerPlane, WordsPerLine, count;
  52   /* is this a Bob or a VSprite? */
  53   if (0 != (vs -> Flags & VSPRITE))
  54   {
  55     /* assumption: vs -> Widtht = 16 (or 32 on a better chipset??)*/
  56     WordsPerLine = vs -> Width >> 4; /* Width:16 */
  57     depth = 2; /* standard */
  58   }
  59   else
  60   {
  61     WordsPerLine = vs -> Width;
  62     depth = vs -> Depth;
  63   }
  64   WordsPerPlane = (vs -> Height) * WordsPerLine;
  65
  66
  67   /* create the standard collision mask by or'ing all bitplanes */
  68   for (count = 0; count < WordsPerPlane; count++)
  69   {
  70     WORD * PlaneData = vs -> ImageData;
  71     WORD Data = PlaneData[count];
  72     LONG z;
  73     for (z = 1; z < depth; z++)
  74         Data |= PlaneData[count + z*WordsPerPlane];
  75     (vs -> CollMask)[count] = Data;
  76   }
  77
  78   /* create the standard BorderLine from the collision mask by or'ing all
  79      lines */
  80   for (count = 0 ; count < WordsPerLine; count++)
  81   {
  82         WORD * CollMask = vs -> CollMask;
  83         WORD Data = CollMask[count];
  84         LONG z;
  85         for (z = 1; z < vs-> Height; z++)
  86           Data |= CollMask[count + z*WordsPerLine];
  87         (vs -> BorderLine)[count] = Data;
  88   }
  89
  90   AROS_LIBFUNC_EXIT
  91 } /* InitMasks */