Add support for Graphos (Amstrad Plus) files.

src/miscfileformats.c

@@ -4683,6 +4683,154 @@ void Save_SCR(T_IO_Context * context)
   free (output);
 }
 
+/**
+ * Test for GO1/GO2/KIT - Amstrad Plus Graphos
+ *
+ * This format is made of 3 files
+ * .KIT hold the palette in "Kit4096" format. There are 16 colors each stored
+ * as 12 bit RGB in RB0G order.
+ * .GO1 and GO2 hold each half of the picture (top and bottom)
+ * The file always cover the whole display of the Plus (196*272 or so)
+ */
+void Test_GOS(T_IO_Context * context, FILE * file)
+{
+  FILE *file_oddeve;
+  unsigned long file_size;
+  file_size = File_length_file(file);
+  if (file_size != 16512) {
+	  File_error = 1;
+	  return;
+  }
+
+  file_oddeve = Open_file_read_with_alternate_ext(context, "GO2");
+  if (file_oddeve == NULL) {
+	  File_error = 2;
+	  return;
+  }
+  file_size = File_length_file(file_oddeve);
+  fclose(file_oddeve);
+  if (file_size != 16512) {
+	  File_error = 3;
+	  return;
+  }
+
+  file_oddeve = Open_file_read_with_alternate_ext(context, "KIT");
+  if (file_oddeve == NULL) {
+	  File_error = 4;
+	  return;
+  }
+  file_size = File_length_file(file_oddeve);
+  fclose(file_oddeve);
+  if (file_size != 160) {
+	  File_error = 5;
+	  return;
+  }
+
+  File_error = 0;
+}
+
+
+void Load_GOS(T_IO_Context* context)
+{
+  FILE *file;
+  long file_size;
+  int i;
+  int x, y;
+  byte * pixel_data;
+
+  if (!(file = Open_file_read(context)))
+  {
+      File_error = 1;
+      return;
+  }
+
+  file_size=File_length_file(file);
+
+  if (CPC_check_AMSDOS(file, NULL, NULL)) {
+    fseek(file, 128, SEEK_SET); // right after AMSDOS header
+  }
+
+  context->Ratio = PIXEL_WIDE;
+  Pre_load(context, 192, 272, file_size, FORMAT_GOS, context->Ratio, 0);
+  context->Width = 192;
+  context->Height = 272;
+
+  // load pixels
+  pixel_data = GFX2_malloc(16384);
+  memset(pixel_data, 0, 16384);
+  Read_bytes(file, pixel_data, file_size);
+
+  i = 0;
+  for (y = 0; y < 168; y++) {
+	  x = 0;
+	  while (x < 192) {
+		  byte pixels = pixel_data[i];
+          Set_pixel(context, x++, y, (pixels & 0x80) >> 7 | (pixels & 0x08) >> 2 | (pixels & 0x20) >> 3 | (pixels & 0x02) << 2);
+          Set_pixel(context, x++, y, (pixels & 0x40) >> 6 | (pixels & 0x04) >> 1 | (pixels & 0x10) >> 2 | (pixels & 0x01) << 3);
+		  i++;
+	  }
+
+	  i += 0x800;
+	  if (i > 0x3FFF) {
+		i -= 0x4000;
+	  } else {
+		i -= 192 / 2;
+	  }
+  }
+
+  fclose(file);
+
+  // load pixels from GO2
+  file = Open_file_read_with_alternate_ext(context, "GO2");
+  if (CPC_check_AMSDOS(file, NULL, NULL)) {
+    fseek(file, 128, SEEK_SET); // right after AMSDOS header
+  }
+  Read_bytes(file, pixel_data, file_size);
+  i = 0;
+  for (y = 168; y < 272; y++) {
+	  x = 0;
+	  while (x < 192) {
+		  byte pixels = pixel_data[i];
+          Set_pixel(context, x++, y, (pixels & 0x80) >> 7 | (pixels & 0x08) >> 2 | (pixels & 0x20) >> 3 | (pixels & 0x02) << 2);
+          Set_pixel(context, x++, y, (pixels & 0x40) >> 6 | (pixels & 0x04) >> 1 | (pixels & 0x10) >> 2 | (pixels & 0x01) << 3);
+		  i++;
+	  }
+
+	  i += 0x800;
+	  if (i > 0x3FFF) {
+		i -= 0x4000;
+	  } else {
+		i -= 192 / 2;
+	  }
+  }
+
+  fclose(file);
+
+  file = Open_file_read_with_alternate_ext(context, "KIT");
+  if (CPC_check_AMSDOS(file, NULL, NULL)) {
+    fseek(file, 128, SEEK_SET); // right after AMSDOS header
+  }
+
+  if (Config.Clear_palette)
+	  memset(context->Palette,0,sizeof(T_Palette));
+
+  for (i = 0; i < 16; i++) {
+	uint16_t word;
+	if (!Read_word_be(file, &word)) {
+		fclose(file);
+		File_error = 2;
+		return;
+	}
+
+	context->Palette[i].R = ((word >>  8) & 0xF) * 0x11;
+	context->Palette[i].G = ((word >>  0) & 0xF) * 0x11;
+	context->Palette[i].B = ((word >> 12) & 0xF) * 0x11;
+  }
+
+  fclose(file);
+  File_error = 0;
+}
+
 /**
  * Test for CM5 - Amstrad CPC "Mode 5" picture
  *