Emulate the ROM to be thumbnailed

Now all that's left is actually rendering that!

Makefile

@@ -338,7 +338,7 @@ endif
 
 cocoa: $(BIN)/SameBoy.app
 quicklook: $(BIN)/SameBoy.qlgenerator
-xdg-thumbnailer: $(BIN)/XdgThumbnailer/sameboy-thumbnailer $(BIN)/SDL/cgb_boot_fast.bin
+xdg-thumbnailer: $(BIN)/XdgThumbnailer/sameboy-thumbnailer $(BIN)/XdgThumbnailer/cgb_boot_fast.bin $(patsubst QuickLook/%.png,$(BIN)/XdgThumbnailer/%.png,$(wildcard QuickLook/*.png))
 sdl: $(SDL_TARGET) $(BIN)/SDL/dmg_boot.bin $(BIN)/SDL/mgb_boot.bin $(BIN)/SDL/cgb0_boot.bin $(BIN)/SDL/cgb_boot.bin $(BIN)/SDL/agb_boot.bin $(BIN)/SDL/sgb_boot.bin $(BIN)/SDL/sgb2_boot.bin $(BIN)/SDL/LICENSE $(BIN)/SDL/registers.sym $(BIN)/SDL/background.bmp $(BIN)/SDL/Shaders $(BIN)/SDL/Palettes
 bootroms: $(BIN)/BootROMs/agb_boot.bin $(BIN)/BootROMs/cgb_boot.bin $(BIN)/BootROMs/cgb0_boot.bin $(BIN)/BootROMs/dmg_boot.bin $(BIN)/BootROMs/mgb_boot.bin $(BIN)/BootROMs/sgb_boot.bin $(BIN)/BootROMs/sgb2_boot.bin
 tester: $(TESTER_TARGET) $(BIN)/tester/dmg_boot.bin $(BIN)/tester/cgb_boot.bin $(BIN)/tester/agb_boot.bin $(BIN)/tester/sgb_boot.bin $(BIN)/tester/sgb2_boot.bin
@@ -615,41 +615,51 @@ $(BIN)/tester/sameboy_tester.exe: $(CORE_OBJECTS) $(SDL_OBJECTS)
 	-@$(MKDIR) -p $(dir $@)
 	$(CC) $^ -o $@ $(LDFLAGS) -Wl,/subsystem:console
 
-$(BIN)/SDL/%.bin: $(BOOTROMS_DIR)/%.bin
-	-@$(MKDIR) -p $(dir $@)
-	cp -f $^ $@
-
 $(BIN)/tester/%.bin: $(BOOTROMS_DIR)/%.bin
 	-@$(MKDIR) -p $(dir $@)
-	cp -f $^ $@
+	cp -f $< $@
 
 $(BIN)/SameBoy.app/Contents/Resources/%.bin: $(BOOTROMS_DIR)/%.bin
 	-@$(MKDIR) -p $(dir $@)
-	cp -f $^ $@
+	cp -f $< $@
 
 $(BIN)/SameBoy-iOS.app/%.bin: $(BOOTROMS_DIR)/%.bin
 	-@$(MKDIR) -p $(dir $@)
-	cp -f $^ $@
+	cp -f $< $@
+
+$(BIN)/XdgThumbnailer/%.png: QuickLook/%.png
+	-@$(MKDIR) -p $(dir $@)
+	cp -f $< $@
+
+$(BIN)/XdgThumbnailer/%.bin: $(BOOTROMS_DIR)/%.bin
+	-@$(MKDIR) -p $(dir $@)
+	cp -f $< $@
+
+$(BIN)/SDL/%.bin: $(BOOTROMS_DIR)/%.bin
+	-@$(MKDIR) -p $(dir $@)
+	cp -f $< $@
 
 $(BIN)/SDL/LICENSE: LICENSE
 	-@$(MKDIR) -p $(dir $@)
-	grep -v "^  " $^ > $@
+	grep -v "^  " $< > $@
 
 $(BIN)/SDL/registers.sym: Misc/registers.sym
 	-@$(MKDIR) -p $(dir $@)
-	cp -f $^ $@
+	cp -f $< $@
 
 $(BIN)/SDL/background.bmp: SDL/background.bmp
 	-@$(MKDIR) -p $(dir $@)
-	cp -f $^ $@
+	cp -f $< $@
 
-$(BIN)/SDL/Shaders: Shaders
+$(BIN)/SDL/Shaders: $(wildcard Shaders/*.fsh)
 	-@$(MKDIR) -p $@
-	cp -rf Shaders/*.fsh $@
+	cp -rf $^ $@
+	touch $@
 
-$(BIN)/SDL/Palettes: Misc/Palettes
+$(BIN)/SDL/Palettes: $(wildcard Misc/Palettes/*.sbp)
 	-@$(MKDIR) -p $@
-	cp -rf Misc/Palettes/*.sbp $@
+	cp -rf $^ $@
+	touch $@
 
 # Boot ROMs
 
@@ -693,6 +703,7 @@ install: sdl xdg-thumbnailer $(DESTDIR)$(PREFIX)/share/mime/packages/sameboy.xml
 	-@$(MKDIR) -p $(dir $(DESTDIR)$(PREFIX))
 	mkdir -p $(DESTDIR)$(DATA_DIR)/ $(DESTDIR)$(PREFIX)/bin/
 	cp -rf $(BIN)/SDL/* $(DESTDIR)$(DATA_DIR)/
+	cp -rf $(BIN)/XdgThumbnailer/* $(DESTDIR)$(DATA_DIR)/
 	mv $(DESTDIR)$(DATA_DIR)/sameboy $(DESTDIR)$(PREFIX)/bin/sameboy
 ifeq ($(DESTDIR),)
 	-update-mime-database -n $(PREFIX)/share/mime

XdgThumbnailer/emulate.c

@@ -0,0 +1,96 @@
+#include "emulate.h"
+
+#include <glib.h>
+#include <stdint.h>
+
+#include "Core/gb.h"
+#include "Core/memory.h"
+#include "glibconfig.h"
+
+#define NB_FRAMES_TO_EMULATE (60 * 10)
+
+#define BOOT_ROM_SIZE (0x100 + 0x800) // The two "parts" of it, which are stored contiguously.
+static char *boot_rom;
+
+void load_boot_rom(void)
+{
+    static char const *boot_rom_path = DATA_DIR "/cgb_boot_fast.bin";
+
+    size_t length;
+    GError *error = NULL;
+    g_file_get_contents(boot_rom_path, &boot_rom, &length, &error);
+
+    if (error) {
+        g_error("Error loading boot ROM from \"%s\": %s", boot_rom_path, error->message);
+        // NOTREACHED
+    }
+    else if (length != BOOT_ROM_SIZE) {
+        g_error("Error loading boot ROM from \"%s\": expected to read %d bytes, got %zu",
+                boot_rom_path, BOOT_ROM_SIZE, length);
+        // NOTREACHED
+    }
+}
+
+void unload_boot_rom(void) { g_free(boot_rom); }
+
+/* --- */
+
+static char *async_input_callback(GB_gameboy_t *gb)
+{
+    return NULL;
+}
+
+static void log_callback(GB_gameboy_t *gb, const char *string, GB_log_attributes attributes)
+{
+    // Swallow any logs.
+}
+
+static void vblank_callback(GB_gameboy_t *gb, GB_vblank_type_t type)
+{
+    unsigned nb_frames_left = GPOINTER_TO_UINT(GB_get_user_data(gb));
+    nb_frames_left--;
+    GB_set_user_data(gb, GUINT_TO_POINTER(nb_frames_left));
+
+    // *Do* render the very last frame.
+    if (nb_frames_left == 0) {
+        GB_set_rendering_disabled(gb, false);
+    }
+}
+
+static uint32_t rgb_encode(GB_gameboy_t *gb, uint8_t r, uint8_t g, uint8_t b)
+{
+    return r | g << 8 | b << 16 | 0xFF << 24;
+}
+
+unsigned emulate(enum FileKind kind, unsigned char const *rom, size_t rom_size, uint32_t screen[static 160 * 144])
+{
+    GB_gameboy_t gb;
+    GB_init(&gb, GB_MODEL_CGB_E);
+
+    GB_load_boot_rom_from_buffer(&gb, (unsigned char const *)boot_rom, sizeof(boot_rom));
+    if (kind == KIND_ISX) {
+        g_assert_not_reached(); // TODO: implement GB_load_isx_from_buffer
+    }
+    else {
+        GB_load_rom_from_buffer(&gb, rom, rom_size);
+    }
+
+    GB_set_user_data(&gb, GUINT_TO_POINTER(NB_FRAMES_TO_EMULATE));
+
+    GB_set_vblank_callback(&gb, vblank_callback);
+    GB_set_pixels_output(&gb, screen);
+    GB_set_rgb_encode_callback(&gb, rgb_encode);
+    GB_set_async_input_callback(&gb, async_input_callback);
+    GB_set_log_callback(&gb, log_callback);
+    GB_set_color_correction_mode(&gb, GB_COLOR_CORRECTION_MODERN_BALANCED);
+
+    GB_set_rendering_disabled(&gb, true);
+    GB_set_turbo_mode(&gb, true, true);
+    while (GPOINTER_TO_UINT(GB_get_user_data(&gb))) {
+        GB_run(&gb);
+    }
+
+    unsigned cgb_flag = GB_read_memory(&gb, 0x143) & 0xC0;
+    GB_free(&gb);
+    return cgb_flag;
+}

XdgThumbnailer/emulate.h

@@ -0,0 +1,15 @@
+#pragma once
+
+#include <stddef.h>
+#include <stdint.h>
+
+enum FileKind {
+    KIND_GB,
+    KIND_GBC,
+    KIND_ISX,
+};
+
+void load_boot_rom(void);
+void unload_boot_rom(void);
+
+unsigned emulate(enum FileKind kind, unsigned char const *rom, size_t rom_size, uint32_t screen[static 160 * 144]);

XdgThumbnailer/main.c

@@ -8,6 +8,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "emulate.h"
 #include "tasks.h"
 #include "thumbnail.h"
 
@@ -110,7 +111,7 @@ int main(int argc, char const *argv[])
     // unsigned active_worker_threads = 0;
     //  Create the task queue *before* starting to accept tasks from D-Bus.
     init_tasks();
-    load_boot_roms();
+    load_boot_rom();
     // Likewise, create the main loop before then, so it can be aborted even before entering it.
     main_loop = g_main_loop_new(NULL, FALSE);
 
@@ -129,12 +130,12 @@ int main(int argc, char const *argv[])
     g_info("Waiting for outstanding tasks...");
     cleanup_tasks(); // Also waits for any remaining tasks.
     // "Pedantic" cleanup for Valgrind et al.
-    unload_boot_roms();
+    unload_boot_rom();
     g_main_loop_unref(main_loop);
     g_bus_unown_name(owner_id);
     if (thumbnailer_interface) {
         g_dbus_interface_skeleton_unexport(G_DBUS_INTERFACE_SKELETON(thumbnailer_interface));
+        g_object_unref(thumbnailer_interface);
     }
-    g_object_unref(thumbnailer_interface);
     return 0;
 }

XdgThumbnailer/thumbnail.c

@@ -2,44 +2,15 @@
 
 #include <gio/gio.h>
 #include <glib.h>
+#include <stdint.h>
 #include <stdlib.h>
 
-#include "Core/gb.h"
-#include "XdgThumbnailer/tasks.h"
+#include "emulate.h"
 #include "main.h"
+#include "tasks.h"
 
 #define THUMBNAILING_ERROR_DOMAIN (g_quark_from_static_string("thumbnailing"))
 
-enum FileKind {
-    KIND_GB,
-    KIND_GBC,
-    KIND_ISX,
-};
-
-#define BOOT_ROM_SIZE (0x100 + 0x800) // The two "parts" of it, which are stored contiguously.
-static char *boot_rom;
-
-void load_boot_roms(void)
-{
-    static char const *boot_rom_path = DATA_DIR "/cgb_boot_fast.bin";
-
-    size_t length;
-    GError *error = NULL;
-    g_file_get_contents(boot_rom_path, &boot_rom, &length, &error);
-
-    if (error) {
-        g_error("Error loading boot ROM from \"%s\": %s", boot_rom_path, error->message);
-        // NOTREACHED
-    }
-    else if (length != BOOT_ROM_SIZE) {
-        g_error("Error loading boot ROM from \"%s\": expected to read %d bytes, got %zu",
-                boot_rom_path, BOOT_ROM_SIZE, length);
-        // NOTREACHED
-    }
-}
-
-void unload_boot_roms(void) { g_free(boot_rom); }
-
 struct TaskData {
     char *contents;
     size_t length;
@@ -59,19 +30,11 @@ static void generate_thumbnail(GTask *task, void *source_object, void *data,
 {
     struct TaskData *task_data = data;
 
-    GB_gameboy_t gb;
-    GB_init(&gb, GB_MODEL_CGB_E);
-    GB_load_boot_rom_from_buffer(&gb, (unsigned char const *)boot_rom, sizeof(boot_rom));
-
-    if (task_data->kind == KIND_ISX) {
-        g_assert_not_reached(); // TODO: implement GB_load_isx_from_buffer
-    }
-    else {
-        GB_load_rom_from_buffer(&gb, (unsigned char const *)task_data->contents, task_data->length);
-    }
-    // TODO
-
-    GB_free(&gb);
+    uint32_t screen[160 * 144];
+    unsigned cgb_flag = emulate(task_data->kind, (unsigned char const *)task_data->contents,
+                                task_data->length, screen);
+    // TODO: generate the thumbnail from `screen` and `cgb_flag`.
+    (void)cgb_flag;
 
     g_task_return_boolean(task, TRUE);
     g_object_unref(task);
@@ -112,7 +75,7 @@ static void on_thumbnailing_end(GObject *source_object, GAsyncResult *res, void
 
     g_assert_null(source_object); // The object that was passed to `g_task_new`.
     GTask *task = G_TASK(res);
-    g_debug("Ending thumbnailing for \"%s\"", g_task_get_name(task));
+    g_info("Ending thumbnailing for \"%s\"", g_task_get_name(task));
     unsigned handle = GPOINTER_TO_UINT(user_data);
     char const *uri = g_task_get_name(task);
 

XdgThumbnailer/thumbnail.h

@@ -3,8 +3,5 @@
 #include <glib.h>
 #include <gio/gio.h>
 
-void load_boot_roms(void);
-void unload_boot_roms(void);
-
 void start_thumbnailing(unsigned handle, GCancellable *cancellable, gboolean is_urgent,
                         char const *uri, char const *mime_type);