AstroImpact/network_protocol

message types:
	asteroid_pos (0x00):
		uint64_t microtimestamp;
		for each asteroid:
			uint16_t id;
			vec vel, pos;
			f32 rot, scale;

	player_pos (0x01):
		server to client:
			uint64_t microtimestamp; // only useful with prediction
			for each player:
				uint8_t id;
				vec pos;
				vec vel; // only useful with prediction
				vec front;
				vec up;
		client to server:
			uint64_t microtimestamp; // only useful with prediction
			vec pos;
			vec vel; // only useful with prediction
			vec front;
			vec up;

	sun_pos (0x02):
		uint64_t microtimestamp;
		f32 location;

	asteroid_destroyed (0x03):
		server to client: // reliable
			uint64_t microtimestamp;
			uint16_t id;
			vec newvel, newpos;
			f32 rot, scale;
		client to server: // confirmed by the server echoing the details back
			uint64_t microtimestamp;
			uint16_t id;

	exo_hit (0x04): // reliable
		uint64_t microtimestamp;
		uint16_t hit_id;
		uint16_t asteroid_id;
		vec oldvel, oldpos, newvel, newpos;
		f32 oldrot, oldscale, newrot, newscale;
		f32 damage_ratio; // > 10.f if the game should end

	player_disconnected (0x05): // reliable
		server to client:
			uint8_t id;

	pod_state_changed (0x06): // reliable
		server to client:
			microtimestamp; // detecting reuse of the same id

		uint8_t new_state; // 0x00: destroyed; 0x01: delivered; 0x02: spawned; 0x03: picked up

		uint16_t pod_id;

		if new_state == destroyed:
			f32 population_dead;
		else if new_state == delivered:
			server to client:
				f32 population_saved;
		else if new_state == spawned:
			vec pos;
		else if new_state == picked up:
			server to client:
				uint8_t player_id;

	exo_hit_recvd (0x80):
		uint16_t hid_id;

	asteroid_destroyed_recvd (0x81):
		uint16_t id;

	player_disconnected_recvd (0x82):
		client to server:
			uint8_t id;

	pod_state_changed_recvd (0x83):
		uint16_t id;

	register_accepted (0xC0):
		uint8_t your_id;
		uint16_t num_asteroids; // 0 = 0x10000

	bad_register_value (0xFE):
		<no data>

	register (0xFF):
		uint64_t epoch;
		uint16_t num_asteroids; // 0 = 0x10000

message format:
	uint64_t protocol_id (0x75F6073677E10C44); // don't want random udp packets 
	uint8_t message type;
	<message-specific data>;