hyperultra/src/entityimpl.h

#pragma once
#include "game.h"
#include "cfg.h"
#include "lzy.h"
#include "entitytag.h"
#include <string.h>

[[maybe_unused]] static void *_draw;
[[maybe_unused]] static void *_update;

#define IMPL(X) static void X(Entity *this, Game *g); \
__attribute__((constructor)) static void init_##X() { _##X = X; } \
static void X([[maybe_unused]] Entity *this, [[maybe_unused]] Game *g)

#define IMPL_INIT(X) static void init(Entity *this, int x, int y); \
__attribute__((constructor)) static void init_tag() { \
	entitytags[num_entitytags].init = init; \
	entitytags[num_entitytags++].name = #X; \
} \
static void _init(Entity *this); \
static void init(Entity *this, int x, int y) { \
	memset(this, 0, sizeof(*this)); \
	this->update = _update; \
	this->draw = _draw; \
	this->pos[0] = x; \
	this->pos[1] = y; \
	this->type = entity_type(#X); \
	_init(this); \
} \
static void _init([[maybe_unused]] Entity *this)