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;
  69         gint height;
  70         gint row;
  71         gint col;
  72         gint mrow;
  73         gint pxs;
  74         gint i;
  75         guint8 attr;
  76         guint8 bright;
  77         guint8 ink;
  78         guint8 paper;
  79         guint8 *ptr;
  80
  81         if (count != 6144 && count != 6912)
  82                 {
  83                 log_printf("Error: zxscr reader error\n");
  84                 return FALSE;
  85                 }
  86
  87         width = 256;
  88         height = 192;
  89
  90         pixels = static_cast<guint8 *>(g_try_malloc(width * height * 3));
  91
  92         if (!pixels)
  93                 {
  94                 log_printf("Error: zxscr reader error\n");
  95                 return FALSE;
  96                 }
  97
  98         ld->pixbuf = gdk_pixbuf_new_from_data(pixels, GDK_COLORSPACE_RGB, FALSE, 8, width, height, width * 3, free_buffer, nullptr);
  99
 100         if (!ld->pixbuf)
 101                 {
 102                 g_free(pixels);
 103                 DEBUG_1("Insufficient memory to open ZXSCR file");
 104                 return FALSE;
 105                 }
 106         //let's decode screen
 107         for (row = 0; row < 24; row++)
 108                 for (col = 0; col < 32; col++)
 109                         {
 110                         if (count == 6144)
 111                                 {
 112                                 //if we have pixels only, make default white ink on black paper
 113                                 bright = 0x01;
 114                                 ink = 0x07;
 115                                 paper = 0x00;
 116                                 }
 117                         else
 118                                 {
 119                                 attr = buf[6144 + row * 32 + col];
 120                                 bright = (attr >> 6) & 0x01;
 121                                 ink = attr & 0x07;
 122                                 paper = ((attr >> 3) & 0x07);
 123                                 }
 124                         ptr = pixels + (row * 256 + col) * 8 * 3;
 125
 126                         for (mrow = 0; mrow < 8; mrow ++)
 127                                 {
 128                                 pxs = buf[(row / 8) * 2048 + mrow * 256 + (row % 8) * 32 + col];
 129                                 for (i = 0; i < 8; i++)
 130                                         {
 131                                         if (pxs & 0x80)
 132                                                 {
 133                                                 *ptr++ = palette[bright][ink][0];       //r
 134                                                 *ptr++ = palette[bright][ink][1];       //g
 135                                                 *ptr++ = palette[bright][ink][2];       //b
 136                                                 }
 137                                         else
 138                                                 {
 139                                                 *ptr++ = palette[bright][paper][0];
 140                                                 *ptr++ = palette[bright][paper][1];
 141                                                 *ptr++ = palette[bright][paper][2];
 142                                                 }
 143                                         pxs <<= 1;
 144                                         }
 145                                 ptr += (31 * 8 * 3);
 146                                 }
 147                         }
 148
 149         ld->area_updated_cb(loader, 0, 0, width, height, ld->data);
 150
 151         return TRUE;
 152 }
 153
 154 static gpointer image_loader_zxscr_new(ImageLoaderBackendCbAreaUpdated area_updated_cb, ImageLoaderBackendCbSize size_cb, ImageLoaderBackendCbAreaPrepared area_prepared_cb, gpointer data)
 155 {
 156         auto loader = g_new0(ImageLoaderZXSCR, 1);
 157         loader->area_updated_cb = area_updated_cb;
 158         loader->size_cb = size_cb;
 159         loader->area_prepared_cb = area_prepared_cb;
 160         loader->data = data;
 161         return loader;
 162 }
 163
 164 static void image_loader_zxscr_set_size(gpointer loader, int width, int height)
 165 {
 166         auto ld = static_cast<ImageLoaderZXSCR *>(loader);
 167         ld->requested_width = width;
 168         ld->requested_height = height;
 169 }
 170
 171 static GdkPixbuf *image_loader_zxscr_get_pixbuf(gpointer loader)
 172 {
 173         auto ld = static_cast<ImageLoaderZXSCR *>(loader);
 174         return ld->pixbuf;
 175 }
 176
 177 static gchar *image_loader_zxscr_get_format_name(gpointer)
 178 {
 179         return g_strdup("zxscr");
 180 }
 181
 182 static gchar **image_loader_zxscr_get_format_mime_types(gpointer)
 183 {
 184         static const gchar *mime[] = {"application/octet-stream", nullptr};
 185         return g_strdupv(const_cast<gchar **>(mime));
 186 }
 187
 188 static gboolean image_loader_zxscr_close(gpointer, GError **)
 189 {
 190         return TRUE;
 191 }
 192
 193 static void image_loader_zxscr_abort(gpointer loader)
 194 {
 195         auto ld = static_cast<ImageLoaderZXSCR *>(loader);
 196         ld->abort = TRUE;
 197 }
 198
 199 static void image_loader_zxscr_free(gpointer loader)
 200 {
 201         auto ld = static_cast<ImageLoaderZXSCR *>(loader);
 202         if (ld->pixbuf) g_object_unref(ld->pixbuf);
 203         g_free(ld);
 204 }
 205
 206 void image_loader_backend_set_zxscr(ImageLoaderBackend *funcs)
 207 {
 208         funcs->loader_new = image_loader_zxscr_new;
 209         funcs->set_size = image_loader_zxscr_set_size;
 210         funcs->load = image_loader_zxscr_load;
 211         funcs->write = nullptr;
 212         funcs->get_pixbuf = image_loader_zxscr_get_pixbuf;
 213         funcs->close = image_loader_zxscr_close;
 214         funcs->abort = image_loader_zxscr_abort;
 215         funcs->free = image_loader_zxscr_free;
 216         funcs->get_format_name = image_loader_zxscr_get_format_name;
 217         funcs->get_format_mime_types = image_loader_zxscr_get_format_mime_types;
 218 }
 219 /* vim: set shiftwidth=8 softtabstop=0 cindent cinoptions={1s: */