rom/graphics/ispointinregion.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Graphics function AndRegionRegion()
   6     Lang: english
   7 */
   8 #include "graphics_intern.h"
   9 #include <graphics/regions.h>
  10 #include "intregions.h"
  11
  12 /*****************************************************************************
  13
  14     NAME */
  15 #include <proto/graphics.h>
  16
  17         AROS_LH3(BOOL, IsPointInRegion,
  18
  19 /*  SYNOPSIS */
  20         AROS_LHA(struct Region *, Reg, A0),
  21         AROS_LHA(WORD,            x,   D0),
  22         AROS_LHA(WORD,            y,   D1),
  23
  24 /*  LOCATION */
  25         struct GfxBase *, GfxBase, 190, Graphics)
  26
  27 /*  FUNCTION
  28         Checks if the point (x, y) is contained in the region Reg
  29
  30     INPUTS
  31         region1 - pointer to a region structure
  32         x       - The point's 'x' coord
  33         y       - The point's 'y' coord
  34
  35     RESULT
  36         TRUE if the point is contained, FALSE otherwise
  37
  38     NOTES
  39
  40     EXAMPLE
  41
  42     BUGS
  43
  44     SEE ALSO
  45         XorRegionRegion(), OrRegionRegion()
  46
  47     INTERNALS
  48
  49     HISTORY
  50
  51 *****************************************************************************/
  52 {
  53     AROS_LIBFUNC_INIT
  54
  55     struct RegionRectangle *rr;
  56
  57     if (!_IsPointInRect(Bounds(Reg), x, y))
  58         return FALSE;
  59
  60     x -= MinX(Reg);
  61     y -= MinY(Reg);
  62
  63     for
  64     (
  65         rr = Reg->RegionRectangle;
  66         rr;
  67         rr = rr->Next
  68     )
  69     {
  70         if (y > MaxY(rr)) continue;
  71         if (y < MinY(rr)) return FALSE;
  72         if (x < MinX(rr)) continue;
  73         if (x > MaxX(rr)) continue;
  74
  75         return TRUE;
  76     }
  77
  78     return FALSE;
  79
  80     AROS_LIBFUNC_EXIT
  81 }