modularization: main, game, balls, c_index, spaceship, gravity

game.h

@@ -0,0 +1,31 @@
+#ifndef GAME_H_INCLUDED
+#define GAME_H_INCLUDED
+
+#include <gtk/gtk.h>
+
+/* simulation/game framework
+ */
+
+extern double delta;		/* simulation time delta in seconds */
+
+#define DEFAULT_DELTA 0.01
+
+extern unsigned int width;	/* game canvas width */
+extern unsigned int height;	/* game canvas height */
+
+#define DEFAULT_WIDTH 800
+#define DEFAULT_HEIGHT 800
+
+extern GtkWidget * canvas;	/* game canvas object */
+
+#if 0
+extern void game_init (); 	/* implemented by the application */
+
+/* game frame function to be provided by the game application */
+extern gboolean game_draw_frame (GtkWidget * widget, cairo_t * cr, gpointer data);
+
+extern void set_game_resize_callback (gboolean (*game_resize) ());
+extern void set_game_keyboard_input_callback (gint (*keyboard_input)(GtkWidget *, GdkEventKey *));
+extern void set_game_mouse_scroll_callback (gboolean (*mouse_scroll)(GtkWidget *, GdkEvent *, gpointer));
+#endif
+#endif