rom/graphics/xorregionregion.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Graphics function XorRegionRegion()
   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_LH2(BOOL, XorRegionRegion,
  18
  19 /*  SYNOPSIS */
  20         AROS_LHA(struct Region *, R1, A0),
  21         AROS_LHA(struct Region *, R2, A1),
  22
  23 /*  LOCATION */
  24         struct GfxBase *, GfxBase, 103, Graphics)
  25
  26 /*  FUNCTION
  27         Exclusive-OR of one region with another region,
  28         leaving result in second region.
  29
  30     INPUTS
  31         region1 - pointer to a region structure
  32         region2 - pointer to a region structure
  33
  34     RESULT
  35         TRUE if the operation was successful,
  36         FALSE otherwise (out of memory)
  37
  38     NOTES
  39
  40
  41     EXAMPLE
  42
  43     BUGS
  44
  45     SEE ALSO
  46         AndRegionRegion(), OrRegionRegion()
  47
  48     INTERNALS
  49
  50     HISTORY
  51         27-11-96    digulla  automatically created from
  52                              graphics_lib.fd and clib/graphics_protos.h
  53         19-01-97    mreckt   intital version
  54
  55         22-09-2001  falemagn changed implementation
  56
  57 *****************************************************************************/
  58 {
  59     AROS_LIBFUNC_INIT
  60
  61     struct Region R3;
  62     struct RegionRectangle *Diff1 = NULL, *Diff2 = NULL;
  63
  64     LONG res;
  65
  66     if
  67     (
  68         !R1->RegionRectangle             ||
  69         !R2->RegionRectangle             ||
  70         !overlap(R1->bounds, R2->bounds)
  71     )
  72     {
  73         return OrRegionRegion(R1, R2);
  74     }
  75
  76     InitRegion(&R3);
  77
  78     res = _DoOperationBandBand
  79     (
  80         _ClearBandBand,
  81         MinX(R1),
  82         MinX(R2),
  83         MinY(R1),
  84         MinY(R2),
  85         R1->RegionRectangle,
  86         R2->RegionRectangle,
  87         &Diff1,
  88         &R3.bounds,
  89         GfxBase
  90     ) &&
  91     _DoOperationBandBand
  92     (
  93         _ClearBandBand,
  94         MinX(R2),
  95         MinX(R1),
  96         MinY(R2),
  97         MinY(R1),
  98         R2->RegionRectangle,
  99         R1->RegionRectangle,
 100         &Diff2,
 101         &R3.bounds,
 102         GfxBase
 103     ) &&
 104     _DoOperationBandBand
 105     (
 106         _OrBandBand,
 107         0,
 108         0,
 109         0,
 110         0,
 111         Diff1,
 112         Diff2,
 113         &R3.RegionRectangle,
 114         &R3.bounds,
 115         GfxBase
 116     );
 117
 118     _DisposeRegionRectangleList(Diff1, GfxBase);
 119     _DisposeRegionRectangleList(Diff2, GfxBase);
 120
 121     if (res)
 122     {
 123         ClearRegion(R2);
 124
 125         *R2 = R3;
 126
 127         _TranslateRegionRectangles(R3.RegionRectangle, -MinX(&R3), -MinY(&R3));
 128     }
 129
 130     return res;
 131
 132     AROS_LIBFUNC_EXIT
 133 }