rom/graphics/textlength.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$         $Log
   4
   5     Desc: Graphics function TextLength()
   6     Lang: english
   7 */
   8 #include "graphics_intern.h"
   9
  10 #undef NUMCHARS
  11 #define NUMCHARS(tf) ((tf->tf_HiChar - tf->tf_LoChar) + 2)
  12
  13 /*****************************************************************************
  14
  15     NAME */
  16 #include <graphics/rastport.h>
  17 #include <proto/graphics.h>
  18
  19         AROS_LH3(WORD, TextLength,
  20
  21 /*  SYNOPSIS */
  22         AROS_LHA(struct RastPort *, rp, A1),
  23         AROS_LHA(CONST_STRPTR     , string, A0),
  24         AROS_LHA(ULONG            , count, D0),
  25
  26 /*  LOCATION */
  27         struct GfxBase *, GfxBase, 9, Graphics)
  28
  29 /*  FUNCTION
  30
  31     INPUTS
  32
  33     RESULT
  34
  35     NOTES
  36
  37     EXAMPLE
  38
  39     BUGS
  40
  41     SEE ALSO
  42
  43     INTERNALS
  44
  45     HISTORY
  46         29-10-95    digulla automatically created from
  47                             graphics_lib.fd and clib/graphics_protos.h
  48
  49 *****************************************************************************/
  50 {
  51     AROS_LIBFUNC_INIT
  52     AROS_LIBBASE_EXT_DECL(struct GfxBase *,GfxBase)
  53
  54     struct TextFont *tf = rp->Font;
  55     WORD            strlen;
  56
  57     if ((tf->tf_Flags & FPF_PROPORTIONAL) || tf->tf_CharKern || tf->tf_CharSpace)
  58     {
  59         WORD  idx;
  60         WORD  defaultidx = NUMCHARS(tf) - 1; /* Last glyph is the default glyph */
  61         UBYTE c;
  62
  63         for(strlen = 0; count; count--)
  64         {
  65             c = *string++;
  66
  67             if ( c < tf->tf_LoChar || c > tf->tf_HiChar)
  68             {
  69                 idx = defaultidx;
  70             }
  71             else
  72             {
  73                 idx = c - tf->tf_LoChar;
  74             }
  75
  76             strlen += ((WORD *)tf->tf_CharKern)[idx];
  77             strlen += ((WORD *)tf->tf_CharSpace)[idx];
  78             strlen += rp->TxSpacing;
  79         }
  80     }
  81     else
  82     {
  83         strlen = count * (tf->tf_XSize + rp->TxSpacing);
  84     }
  85
  86     return strlen;
  87
  88     AROS_LIBFUNC_EXIT
  89
  90 } /* TextLength */