"Fossies" - the Fresh Open Source Software Archive

Member "xearth-1.1/gif.c" (7 Nov 1999, 3286 Bytes) of package /linux/misc/old/xearth-1.1.tar.gz:

    1 /*
    2  * gif.c
    3  * kirk johnson
    4  * july 1993
    5  *
    6  * Copyright (C) 1989, 1990, 1993-1995, 1999 Kirk Lauritz Johnson
    7  *
    8  * Parts of the source code (as marked) are:
    9  *   Copyright (C) 1989, 1990, 1991 by Jim Frost
   10  *   Copyright (C) 1992 by Jamie Zawinski <jwz@lucid.com>
   11  *
   12  * Permission to use, copy, modify and freely distribute xearth for
   13  * non-commercial and not-for-profit purposes is hereby granted
   14  * without fee, provided that both the above copyright notice and this
   15  * permission notice appear in all copies and in supporting
   16  * documentation.
   17  *
   18  * Unisys Corporation holds worldwide patent rights on the Lempel Zev
   19  * Welch (LZW) compression technique employed in the CompuServe GIF
   20  * image file format as well as in other formats. Unisys has made it
   21  * clear, however, that it does not require licensing or fees to be
   22  * paid for freely distributed, non-commercial applications (such as
   23  * xearth) that employ LZW/GIF technology. Those wishing further
   24  * information about licensing the LZW patent should contact Unisys
   25  * directly at (lzw_info@unisys.com) or by writing to
   26  *
   27  *   Unisys Corporation
   28  *   Welch Licensing Department
   29  *   M/S-C1SW19
   30  *   P.O. Box 500
   31  *   Blue Bell, PA 19424
   32  *
   33  * The author makes no representations about the suitability of this
   34  * software for any purpose. It is provided "as is" without express or
   35  * implied warranty.
   36  *
   37  * THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
   38  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
   39  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, INDIRECT
   40  * OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
   41  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
   42  * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
   43  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   44  */
   45 
   46 #include "xearth.h"
   47 #include "giflib.h"
   48 #include "kljcpyrt.h"
   49 
   50 static void gif_setup _P((FILE *));
   51 static int  gif_row _P((u_char *));
   52 static void gif_cleanup _P((void));
   53 
   54 static u16or32 *dith;
   55 
   56 
   57 void gif_output()
   58 {
   59   compute_positions();
   60   scan_map();
   61   do_dots();
   62   gif_setup(stdout);
   63   render(gif_row);
   64   gif_cleanup();
   65 }
   66 
   67 
   68 static void gif_setup(s)
   69      FILE *s;
   70 {
   71   int  i;
   72   int  rtn;
   73   BYTE cmap[3][256];
   74 
   75   if (num_colors > 256)
   76     fatal("number of colors must be <= 256 with GIF output");
   77 
   78   dither_setup(num_colors);
   79   dith = (u16or32 *) malloc((unsigned) sizeof(u16or32) * wdth);
   80   assert(dith != NULL);
   81 
   82   for (i=0; i<dither_ncolors; i++)
   83   {
   84     cmap[0][i] = dither_colormap[i*3+0];
   85     cmap[1][i] = dither_colormap[i*3+1];
   86     cmap[2][i] = dither_colormap[i*3+2];
   87   }
   88 
   89   rtn = gifout_open_file(s, wdth, hght, dither_ncolors, cmap, 0);
   90   assert(rtn == GIFLIB_SUCCESS);
   91 
   92   rtn = gifout_open_image(0, 0, wdth, hght);
   93   assert(rtn == GIFLIB_SUCCESS);
   94 }
   95 
   96 
   97 static int gif_row(row)
   98      u_char *row;
   99 {
  100   int      i, i_lim;
  101   u16or32 *tmp;
  102 
  103   tmp = dith;
  104   dither_row(row, tmp);
  105 
  106   /* use i_lim to encourage compilers to register loop limit
  107    */
  108   i_lim = wdth;
  109   for (i=0; i<i_lim; i++)
  110     gifout_put_pixel((int) tmp[i]);
  111 
  112   return 0;
  113 }
  114 
  115 
  116 static void gif_cleanup()
  117 {
  118   int rtn;
  119 
  120   rtn = gifout_close_image();
  121   assert(rtn == GIFLIB_SUCCESS);
  122 
  123   rtn = gifout_close_file();
  124   assert(rtn == GIFLIB_SUCCESS);
  125 
  126   dither_cleanup();
  127   free(dith);
  128 }