workbench/libs/cgfx/writepixelarrayalpha.c

   1 /*
   2     Copyright © 1995-2013, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc:
   6     Lang: english
   7 */
   8
   9 #include <hidd/graphics.h>
  10 #include <aros/debug.h>
  11
  12 #include "cybergraphics_intern.h"
  13 #include "gfxfuncsupport.h"
  14
  15 struct render_data
  16 {
  17     UBYTE *array;
  18     ULONG modulo;
  19 };
  20
  21 static ULONG RenderHook(struct render_data *data, LONG srcx, LONG srcy,
  22     OOP_Object *dstbm_obj, OOP_Object *dst_gc, struct Rectangle *rect,
  23     struct GfxBase *GfxBase);
  24
  25 /*****************************************************************************
  26
  27     NAME */
  28 #include <proto/cybergraphics.h>
  29
  30         AROS_LH10(ULONG, WritePixelArrayAlpha,
  31
  32 /*  SYNOPSIS */
  33         AROS_LHA(APTR             , src         , A0),
  34         AROS_LHA(UWORD            , srcx        , D0),
  35         AROS_LHA(UWORD            , srcy        , D1),
  36         AROS_LHA(UWORD            , srcmod      , D2),
  37         AROS_LHA(struct RastPort *, rp          , A1),
  38         AROS_LHA(UWORD            , destx       , D3),
  39         AROS_LHA(UWORD            , desty       , D4),
  40         AROS_LHA(UWORD            , width       , D5),
  41         AROS_LHA(UWORD            , height      , D6),
  42         AROS_LHA(ULONG            , globalalpha , D7),
  43
  44 /*  LOCATION */
  45         struct Library *, CyberGfxBase, 36, Cybergraphics)
  46
  47 /*  FUNCTION
  48         Alpha-blends all or part of a rectangular block of raw pixel values
  49         into a RastPort. The source data must be in 32-bit ARGB format: 1 byte
  50         per component, in the order alpha, red, green, blue.
  51
  52     INPUTS
  53         srcRect - pointer to the pixel values.
  54         srcx, srcy - top-lefthand corner of portion of source rectangle to
  55             use (in pixels).
  56         srcmod - the number of bytes in each row of the source rectangle.
  57         rp - the RastPort to write to.
  58         destx, desty - top-lefthand corner of portion of destination RastPort
  59             to write to (in pixels).
  60         width, height - size of the affected area (in pixels).
  61         globalalpha - an alpha value applied globally to every pixel taken
  62             from the source rectangle (the full 32-bit range of values is
  63             used: 0 to 0xFFFFFFFF).
  64
  65     RESULT
  66         count - the number of pixels written to.
  67
  68     NOTES
  69         Because of the X11 driver you have to set the drawmode
  70         to JAM1 with SetDrMd().
  71
  72     EXAMPLE
  73
  74     BUGS
  75         The globalalpha parameter is currently ignored.
  76
  77     SEE ALSO
  78         WritePixelArray(), graphics.library/SetDrMd()
  79
  80     INTERNALS
  81
  82 *****************************************************************************/
  83 {
  84     AROS_LIBFUNC_INIT
  85
  86     ULONG start_offset;
  87     LONG pixwritten = 0;
  88     struct render_data data;
  89     struct Rectangle rr;
  90
  91     if (width == 0 || height == 0)
  92         return 0;
  93
  94     /* This is cybergraphx. We only work wih HIDD bitmaps */
  95     if (!IS_HIDD_BM(rp->BitMap))
  96     {
  97         D(bug("!!!!! Trying to use CGFX call on non-hidd bitmap "
  98             "in WritePixelArrayAlpha() !!!\n"));
  99         return 0;
 100     }
 101
 102     /* Compute the start of the array */
 103
 104     start_offset = ((ULONG)srcy) * srcmod + srcx * 4;
 105
 106     data.array  = ((UBYTE *)src) + start_offset;
 107     data.modulo = srcmod;
 108
 109     rr.MinX = destx;
 110     rr.MinY = desty;
 111     rr.MaxX = destx + width  - 1;
 112     rr.MaxY = desty + height - 1;
 113
 114     pixwritten = DoRenderFunc(rp, NULL, &rr, RenderHook, &data, TRUE);
 115
 116     return pixwritten;
 117
 118     AROS_LIBFUNC_EXIT
 119 } /* WritePixelArrayAlpha */
 120
 121 static ULONG RenderHook(struct render_data *data, LONG srcx, LONG srcy,
 122     OOP_Object *dstbm_obj, OOP_Object *dst_gc, struct Rectangle *rect,
 123     struct GfxBase *GfxBase)
 124 {
 125     ULONG  width  = rect->MaxX - rect->MinX + 1;
 126     ULONG  height = rect->MaxY - rect->MinY + 1;
 127     UBYTE *array = data->array + data->modulo * srcy + 4 * srcx;
 128
 129     HIDD_BM_PutAlphaImage(dstbm_obj, dst_gc, array, data->modulo,
 130         rect->MinX, rect->MinY, width, height);
 131
 132     return width * height;
 133 }
 134