plugins/libwmfun/fade.c

   1 /*
   2  *  libwmfun - WindowMaker texture function library
   3  *  Copyright (C) 1999 Tobias Gloth
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; either version 2 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to the Free Software
  17  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  18  *  USA.
  19  */
  20
  21 #include "getopt.h"
  22 #include <math.h>
  23 #include <stdlib.h>
  24 #include <time.h>
  25
  26 #include "generic.h"
  27
  28 RImage *fade (int argc, char **argv, int width, int height, int relief) {
  29
  30         int from[3] = { 0x00, 0x00, 0x00 };
  31         int to[3] = { 0xff, 0xff, 0xff };
  32         int *this, *last;
  33         RImage *image;
  34         unsigned char *cptr;
  35         int i, j;
  36         double factor, delta;
  37
  38         int c, done, option_index = 0;
  39
  40         optind = 1;
  41         for (done=0; !done; ) {
  42                 static struct option long_options[] = {
  43                         {"from", 1, 0, 'f'},
  44                         {"to", 1, 0, 't'},
  45                         {0, 0, 0, 0}
  46                 };
  47
  48                 c = getopt_long (argc, argv, "f:t:",
  49                         long_options, &option_index);
  50                 if (c == -1) {
  51                         break;
  52                 }
  53
  54                 switch (c) {
  55                 case 'f':
  56                         if (!parse_color (optarg, from)) {
  57                                 error ("invalid color: %s\n", optarg);
  58                                 return 0;
  59                         }
  60                         break;
  61                 case 't':
  62                         if (!parse_color (optarg, to)) {
  63                                 error ("invalid color: %s\n", optarg);
  64                                 return 0;
  65                         }
  66                         break;
  67                 default:
  68                         done = 1;
  69                         break;
  70                 }
  71         }
  72
  73         argc -= optind;
  74         argv += optind;
  75
  76         if (!start_image ("fade", argc, 0, 1, width, height, &image)) {
  77                 return (RImage *)0;
  78         }
  79
  80         this = (int *) malloc (width * sizeof (int));
  81         last = (int *) malloc (width * sizeof (int));
  82         if (!this || !last) {
  83                 RReleaseImage (image);
  84                 free (this);
  85                 free (last);
  86                 return (RImage *)0;
  87         }
  88
  89         for (i=0; i<width; i++) {
  90                 this[i] = 255;
  91         }
  92
  93         factor = pow (0.2, 1.0 / height);
  94         delta = (factor < 0.5) ? 2.0 * factor : 2.0 * (1.0 - factor);
  95
  96         srand (time (0));
  97
  98         cptr = image->data;
  99         for (j=0; j<height; j++) {
 100                 memcpy (last, this, width * sizeof (int));
 101                 for (i=0; i<width; i++) {
 102                         int output[3];
 103                         int k = i + random_int (3) - 1;
 104                         double f = factor + random_double (delta) - delta/2.0;
 105
 106                         if (k < 0) {
 107                                 k = 0;
 108                         }
 109                         if (k >= width) {
 110                                 k = width - 1;
 111                         }
 112
 113                         this[i] = (int) (f * last[k]);
 114                         interpolate_color (output, from, to, this[i]);
 115                         *cptr++ = output[0];
 116                         *cptr++ = output[1];
 117                         *cptr++ = output[2];
 118                         if (RRGBAFormat==image->format)
 119                                 cptr++;
 120                 }
 121         }
 122
 123         free (this);
 124         free (last);
 125
 126         return image;
 127 }
 128