rom/graphics/initgels.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Graphics function InitGels()
   6     Lang: english
   7 */
   8 #include "graphics_intern.h"
   9 #include <graphics/rastport.h>
  10 #include <graphics/gels.h>
  11 #include <proto/exec.h>
  12
  13 #include "gels_internal.h"
  14
  15 /*****************************************************************************
  16
  17     NAME */
  18 #include <proto/graphics.h>
  19
  20         AROS_LH3(void, InitGels,
  21
  22 /*  SYNOPSIS */
  23         AROS_LHA(struct VSprite *, head, A0),
  24         AROS_LHA(struct VSprite *, tail, A1),
  25         AROS_LHA(struct GelsInfo *, GInfo, A2),
  26
  27 /*  LOCATION */
  28         struct GfxBase *, GfxBase, 20, Graphics)
  29
  30 /*  FUNCTION
  31         Makes the two VSprites head and tail of the gel list that is connected
  32         to the GelsInfo structure. The two VSprites are linked together and
  33         their x and y coordinates are initilized such that the serve as the
  34         keystones of the list.
  35
  36     INPUTS
  37         head  - pointer to the VSprite structure to be used as head of the gel list
  38         tail  - pointer to the VSprite structure to be used as tail of the gel list
  39         GInfo - pointer to the GelsInfo structure to be initilized
  40
  41     RESULT
  42
  43     NOTES
  44
  45     EXAMPLE
  46
  47     BUGS
  48
  49     SEE ALSO
  50         graphics/rastport.h  graphics/gels.h
  51
  52     INTERNALS
  53
  54     HISTORY
  55
  56
  57 *****************************************************************************/
  58 {
  59         AROS_LIBFUNC_INIT
  60         AROS_LIBBASE_EXT_DECL(struct GfxBase *,GfxBase)
  61
  62         /* initilize the head's coordinates with the lowest possible values */
  63         head -> OldY = 0x8000;
  64         head -> OldX = 0x8000;
  65         head -> Y    = 0x8000;
  66         head -> X    = 0x8000;
  67
  68         /* initilize the tail's coordinates with the highest possible values */
  69         tail -> OldY = 0x7FFF;
  70         tail -> OldX = 0x7FFF;
  71         tail -> Y    = 0x7FFF;
  72         tail -> X    = 0x7FFF;
  73
  74         /* now link it to the gelsinfo and interconnect them */
  75         GInfo -> gelHead = head;
  76         GInfo -> gelTail = tail;
  77
  78         head -> NextVSprite = tail;
  79         head -> ClearPath   = tail;
  80         tail -> PrevVSprite = head;
  81
  82         head -> IntVSprite = NULL;
  83         tail -> IntVSprite = NULL;
  84
  85         AROS_LIBFUNC_EXIT
  86 } /* InitGels */