rom/graphics/clearrectregion.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Graphics function ClearRectRegion()
   6     Lang: english
   7 */
   8 #include "graphics_intern.h"
   9 #include <graphics/regions.h>
  10 #include <proto/graphics.h>
  11 #include "intregions.h"
  12
  13 /*****************************************************************************
  14
  15     NAME */
  16 #include <clib/graphics_protos.h>
  17
  18         AROS_LH2(BOOL, ClearRectRegion,
  19
  20 /*  SYNOPSIS */
  21         AROS_LHA(struct Region    *, Reg   , A0),
  22         AROS_LHA(struct Rectangle *, Rect, A1),
  23
  24 /*  LOCATION */
  25         struct GfxBase *, GfxBase, 87, Graphics)
  26
  27 /*  FUNCTION
  28         Clear the given Rectangle from the given Region
  29
  30     INPUTS
  31         region - pointer to a Region structure
  32         rectangle - pointer to a Rectangle structure
  33
  34     RESULT
  35         FALSE if not enough memory was available, else TRUE
  36
  37     NOTES
  38
  39     EXAMPLE
  40
  41     BUGS
  42
  43     SEE ALSO
  44         AndRectRegion(), OrRectRegion(), XorRectRegion()
  45
  46     INTERNALS
  47
  48     HISTORY
  49         27-11-96    digulla automatically created from
  50                             graphics_lib.fd and clib/graphics_protos.h
  51         20-01-96    mreckt  initial version
  52
  53 *****************************************************************************/
  54 {
  55     AROS_LIBFUNC_INIT
  56
  57     struct Region Res;
  58     struct RegionRectangle rr;
  59
  60     /* If the rectangle and the region don't overlap just return */
  61     if (!overlap(*Rect, Reg->bounds))
  62         return TRUE;
  63
  64     /* if the rectangle completely covers the region just clear the region and return */
  65     if
  66     (
  67         Rect->MinX <= MinX(Reg) &&
  68         Rect->MinY <= MinY(Reg) &&
  69         Rect->MaxX >= MaxX(Reg) &&
  70         Rect->MaxY >= MaxY(Reg)
  71     )
  72     {
  73         ClearRegion(Reg);
  74         return TRUE;
  75     }
  76
  77     InitRegion(&Res);
  78
  79     rr.bounds = *Rect;
  80     rr.Next   = NULL;
  81     rr.Prev   = NULL;
  82
  83     if
  84     (
  85         _DoOperationBandBand
  86         (
  87             _ClearBandBand,
  88             0,
  89             MinX(Reg),
  90             0,
  91             MinY(Reg),
  92             &rr,
  93             Reg->RegionRectangle,
  94             &Res.RegionRectangle,
  95             &Res.bounds,
  96             GfxBase
  97         )
  98     )
  99     {
 100         ClearRegion(Reg);
 101
 102         *Reg = Res;
 103
 104         _TranslateRegionRectangles(Res.RegionRectangle, -MinX(&Res), -MinY(&Res));
 105
 106         return TRUE;
 107     }
 108
 109     return FALSE;
 110
 111     AROS_LIBFUNC_EXIT
 112 } /* ClearRectRegion */