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 /*
  22  * $Id$
  23  *
  24  * $Log$
  25  * Revision 1.1  2000/12/03 18:58:41  id
  26  * initiate plugins branch
  27  *
  28  * Revision 1.1.1.1  1999/02/21 17:16:47  gloth
  29  * initial revision
  30  *
  31  */
  32
  33 #include "getopt.h"
  34 #include <math.h>
  35 #include <stdlib.h>
  36 #include <time.h>
  37
  38 #include "generic.h"
  39
  40 RImage *fade (int argc, char **argv, int width, int height, int relief) {
  41
  42         int from[3] = { 0x00, 0x00, 0x00 };
  43         int to[3] = { 0xff, 0xff, 0xff };
  44         int *this, *last;
  45         RImage *image;
  46         unsigned char *cptr;
  47         int i, j;
  48         double factor, delta;
  49
  50         int c, done, option_index = 0;
  51
  52         optind = 1;
  53         for (done=0; !done; ) {
  54                 static struct option long_options[] = {
  55                         {"from", 1, 0, 'f'},
  56                         {"to", 1, 0, 't'},
  57                         {0, 0, 0, 0}
  58                 };
  59
  60                 c = getopt_long (argc, argv, "f:t:",
  61                         long_options, &option_index);
  62                 if (c == -1) {
  63                         break;
  64                 }
  65
  66                 switch (c) {
  67                 case 'f':
  68                         if (!parse_color (optarg, from)) {
  69                                 error ("invalid color: %s\n", optarg);
  70                                 return 0;
  71                         }
  72                         break;
  73                 case 't':
  74                         if (!parse_color (optarg, to)) {
  75                                 error ("invalid color: %s\n", optarg);
  76                                 return 0;
  77                         }
  78                         break;
  79                 default:
  80                         done = 1;
  81                         break;
  82                 }
  83         }
  84
  85         argc -= optind;
  86         argv += optind;
  87
  88         if (!start_image ("fade", argc, 0, 1, width, height, &image)) {
  89                 return (RImage *)0;
  90         }
  91
  92         this = (int *) malloc (width * sizeof (int));
  93         last = (int *) malloc (width * sizeof (int));
  94         if (!this || !last) {
  95                 RDestroyImage (image);
  96                 free (this);
  97                 free (last);
  98                 return (RImage *)0;
  99         }
 100
 101         for (i=0; i<width; i++) {
 102                 this[i] = 255;
 103         }
 104
 105         factor = pow (0.2, 1.0 / height);
 106         delta = (factor < 0.5) ? 2.0 * factor : 2.0 * (1.0 - factor);
 107
 108         srand (time (0));
 109
 110         cptr = image->data;
 111         for (j=0; j<height; j++) {
 112                 memcpy (last, this, width * sizeof (int));
 113                 for (i=0; i<width; i++) {
 114                         int output[3];
 115                         int k = i + random_int (3) - 1;
 116                         double f = factor + random_double (delta) - delta/2.0;
 117
 118                         if (k < 0) {
 119                                 k = 0;
 120                         }
 121                         if (k >= width) {
 122                                 k = width - 1;
 123                         }
 124
 125                         this[i] = (int) (f * last[k]);
 126                         interpolate_color (output, from, to, this[i]);
 127                         *cptr++ = output[0];
 128                         *cptr++ = output[1];
 129                         *cptr++ = output[2];
 130                         if (RRGBAFormat==image->format)
 131                                 cptr++;
 132                 }
 133         }
 134
 135         free (this);
 136         free (last);
 137
 138         return image;
 139 }
 140