src/image-load-zxscr.cc

   1 /*
   2  * Copyright (C) 2021 - The Geeqie Team
   3  *
   4  * Author: Dusan Gallo
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #include "main.h"
  22
  23 #include "image-load.h"
  24 #include "image-load-zxscr.h"
  25
  26 struct ImageLoaderZXSCR {
  27         ImageLoaderBackendCbAreaUpdated area_updated_cb;
  28         ImageLoaderBackendCbSize size_cb;
  29         ImageLoaderBackendCbAreaPrepared area_prepared_cb;
  30         gpointer data;
  31         GdkPixbuf *pixbuf;
  32         guint requested_width;
  33         guint requested_height;
  34         gboolean abort;
  35 };
  36
  37 const guchar palette[2][8][3] = {
  38         {
  39                 {0x00, 0x00, 0x00},
  40                 {0x00, 0x00, 0xbf},
  41                 {0xbf, 0x00, 0x00},
  42                 {0xbf, 0x00, 0xbf},
  43                 {0x00, 0xbf, 0x00},
  44                 {0x00, 0xbf, 0xbf},
  45                 {0xbf, 0xbf, 0x00},
  46                 {0xbf, 0xbf, 0xbf}
  47         }, {
  48                 {0x00, 0x00, 0x00},
  49                 {0x00, 0x00, 0xff},
  50                 {0xff, 0x00, 0x00},
  51                 {0xff, 0x00, 0xff},
  52                 {0x00, 0xff, 0x00},
  53                 {0x00, 0xff, 0xff},
  54                 {0xff, 0xff, 0x00},
  55                 {0xff, 0xff, 0xff}
  56         }
  57 };
  58
  59 static void free_buffer(guchar *pixels, gpointer)
  60 {
  61         g_free(pixels);
  62 }
  63
  64 static gboolean image_loader_zxscr_load(gpointer loader, const guchar *buf, gsize count, GError **)
  65 {
  66         auto ld = static_cast<ImageLoaderZXSCR *>(loader);
  67         guint8 *pixels;
  68         gint width, height;
  69         gint row, col, mrow, pxs, i;
  70         guint8 attr, bright, ink, paper;
  71         guint8 *ptr;
  72
  73         if (count != 6144 && count != 6912)
  74                 {
  75                 log_printf("Error: zxscr reader error\n");
  76                 return FALSE;
  77                 }
  78
  79         width = 256;
  80         height = 192;
  81
  82         pixels = static_cast<guint8 *>(g_try_malloc(width * height * 3));
  83
  84         if (!pixels)
  85                 {
  86                 log_printf("Error: zxscr reader error\n");
  87                 return FALSE;
  88                 }
  89
  90         ld->pixbuf = gdk_pixbuf_new_from_data(pixels, GDK_COLORSPACE_RGB, FALSE, 8, width, height, width * 3, free_buffer, nullptr);
  91
  92         if (!ld->pixbuf)
  93                 {
  94                 g_free(pixels);
  95                 DEBUG_1("Insufficient memory to open ZXSCR file");
  96                 return FALSE;
  97                 }
  98         //let's decode screen
  99         for (row = 0; row < 24; row++)
 100                 for (col = 0; col < 32; col++)
 101                         {
 102                         if (count == 6144)
 103                                 {
 104                                 //if we have pixels only, make default white ink on black paper
 105                                 bright = 0x01;
 106                                 ink = 0x07;
 107                                 paper = 0x00;
 108                                 }
 109                         else
 110                                 {
 111                                 attr = buf[6144 + row * 32 + col];
 112                                 bright = (attr >> 6) & 0x01;
 113                                 ink = attr & 0x07;
 114                                 paper = ((attr >> 3) & 0x07);
 115                                 }
 116                         ptr = pixels + (row * 256 + col) * 8 * 3;
 117
 118                         for (mrow = 0; mrow < 8; mrow ++)
 119                                 {
 120                                 pxs = buf[(row / 8) * 2048 + mrow * 256 + (row % 8) * 32 + col];
 121                                 for (i = 0; i < 8; i++)
 122                                         {
 123                                         if (pxs & 0x80)
 124                                                 {
 125                                                 *ptr++ = palette[bright][ink][0];       //r
 126                                                 *ptr++ = palette[bright][ink][1];       //g
 127                                                 *ptr++ = palette[bright][ink][2];       //b
 128                                                 }
 129                                         else
 130                                                 {
 131                                                 *ptr++ = palette[bright][paper][0];
 132                                                 *ptr++ = palette[bright][paper][1];
 133                                                 *ptr++ = palette[bright][paper][2];
 134                                                 }
 135                                         pxs <<= 1;
 136                                         }
 137                                 ptr += (31 * 8 * 3);
 138                                 }
 139                         }
 140
 141         ld->area_updated_cb(loader, 0, 0, width, height, ld->data);
 142
 143         return TRUE;
 144 }
 145
 146 static gpointer image_loader_zxscr_new(ImageLoaderBackendCbAreaUpdated area_updated_cb, ImageLoaderBackendCbSize size_cb, ImageLoaderBackendCbAreaPrepared area_prepared_cb, gpointer data)
 147 {
 148         auto loader = g_new0(ImageLoaderZXSCR, 1);
 149         loader->area_updated_cb = area_updated_cb;
 150         loader->size_cb = size_cb;
 151         loader->area_prepared_cb = area_prepared_cb;
 152         loader->data = data;
 153         return loader;
 154 }
 155
 156 static void image_loader_zxscr_set_size(gpointer loader, int width, int height)
 157 {
 158         auto ld = static_cast<ImageLoaderZXSCR *>(loader);
 159         ld->requested_width = width;
 160         ld->requested_height = height;
 161 }
 162
 163 static GdkPixbuf *image_loader_zxscr_get_pixbuf(gpointer loader)
 164 {
 165         auto ld = static_cast<ImageLoaderZXSCR *>(loader);
 166         return ld->pixbuf;
 167 }
 168
 169 static gchar *image_loader_zxscr_get_format_name(gpointer)
 170 {
 171         return g_strdup("zxscr");
 172 }
 173
 174 static gchar **image_loader_zxscr_get_format_mime_types(gpointer)
 175 {
 176         static const gchar *mime[] = {"application/octet-stream", nullptr};
 177         return g_strdupv(const_cast<gchar **>(mime));
 178 }
 179
 180 static gboolean image_loader_zxscr_close(gpointer, GError **)
 181 {
 182         return TRUE;
 183 }
 184
 185 static void image_loader_zxscr_abort(gpointer loader)
 186 {
 187         auto ld = static_cast<ImageLoaderZXSCR *>(loader);
 188         ld->abort = TRUE;
 189 }
 190
 191 static void image_loader_zxscr_free(gpointer loader)
 192 {
 193         auto ld = static_cast<ImageLoaderZXSCR *>(loader);
 194         if (ld->pixbuf) g_object_unref(ld->pixbuf);
 195         g_free(ld);
 196 }
 197
 198 void image_loader_backend_set_zxscr(ImageLoaderBackend *funcs)
 199 {
 200         funcs->loader_new = image_loader_zxscr_new;
 201         funcs->set_size = image_loader_zxscr_set_size;
 202         funcs->load = image_loader_zxscr_load;
 203         funcs->write = nullptr;
 204         funcs->get_pixbuf = image_loader_zxscr_get_pixbuf;
 205         funcs->close = image_loader_zxscr_close;
 206         funcs->abort = image_loader_zxscr_abort;
 207         funcs->free = image_loader_zxscr_free;
 208         funcs->get_format_name = image_loader_zxscr_get_format_name;
 209         funcs->get_format_mime_types = image_loader_zxscr_get_format_mime_types;
 210 }
 211 /* vim: set shiftwidth=8 softtabstop=0 cindent cinoptions={1s: */