godot/scene/multiplayer/scene_rpc_interface.h

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/*  scene_rpc_interface.h                                                */
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/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
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#ifndef SCENE_RPC_INTERFACE_H
#define SCENE_RPC_INTERFACE_H

#include "core/multiplayer/multiplayer.h"
#include "core/multiplayer/multiplayer_api.h"

class SceneRPCInterface : public MultiplayerRPCInterface {
	GDCLASS(SceneRPCInterface, MultiplayerRPCInterface);

private:
	enum NetworkNodeIdCompression {
		NETWORK_NODE_ID_COMPRESSION_8 = 0,
		NETWORK_NODE_ID_COMPRESSION_16,
		NETWORK_NODE_ID_COMPRESSION_32,
	};

	enum NetworkNameIdCompression {
		NETWORK_NAME_ID_COMPRESSION_8 = 0,
		NETWORK_NAME_ID_COMPRESSION_16,
	};

	// The RPC meta is composed by a single byte that contains (starting from the least significant bit):
	// - `NetworkCommands` in the first four bits.
	// - `NetworkNodeIdCompression` in the next 2 bits.
	// - `NetworkNameIdCompression` in the next 1 bit.
	// - `byte_only_or_no_args` in the next 1 bit.
	enum {
		NODE_ID_COMPRESSION_SHIFT = MultiplayerAPI::CMD_FLAG_0_SHIFT, // 2 bits for this.
		NAME_ID_COMPRESSION_SHIFT = MultiplayerAPI::CMD_FLAG_2_SHIFT,
		BYTE_ONLY_OR_NO_ARGS_SHIFT = MultiplayerAPI::CMD_FLAG_3_SHIFT,
	};

	enum {
		NODE_ID_COMPRESSION_FLAG = (1 << NODE_ID_COMPRESSION_SHIFT) | (1 << (NODE_ID_COMPRESSION_SHIFT + 1)), // 2 bits for this.
		NAME_ID_COMPRESSION_FLAG = (1 << NAME_ID_COMPRESSION_SHIFT),
		BYTE_ONLY_OR_NO_ARGS_FLAG = (1 << BYTE_ONLY_OR_NO_ARGS_SHIFT),
	};

	MultiplayerAPI *multiplayer = nullptr;
	Vector<uint8_t> packet_cache;

protected:
	static MultiplayerRPCInterface *_create(MultiplayerAPI *p_multiplayer);

	_FORCE_INLINE_ void _profile_node_data(const String &p_what, ObjectID p_id);
	void _process_rpc(Node *p_node, const uint16_t p_rpc_method_id, int p_from, const uint8_t *p_packet, int p_packet_len, int p_offset);

	void _send_rpc(Node *p_from, int p_to, uint16_t p_rpc_id, const Multiplayer::RPCConfig &p_config, const StringName &p_name, const Variant **p_arg, int p_argcount);
	Node *_process_get_node(int p_from, const uint8_t *p_packet, uint32_t p_node_target, int p_packet_len);

public:
	static void make_default();

	virtual void rpcp(Object *p_obj, int p_peer_id, const StringName &p_method, const Variant **p_arg, int p_argcount) override;
	virtual void process_rpc(int p_from, const uint8_t *p_packet, int p_packet_len) override;
	virtual String get_rpc_md5(const Object *p_obj) const override;

	SceneRPCInterface(MultiplayerAPI *p_multiplayer) { multiplayer = p_multiplayer; }
};

#endif // SCENE_RPC_INTERFACE_H