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/*
Minetest
Copyright (C) 2010-2017 celeron55, Perttu Ahola <celeron55@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#pragma once

#include "environment.h"
#include <ISceneManager.h>
#include "clientobject.h"
#include "util/numeric.h"

class ClientSimpleObject;
class ClientMap;
class ClientScripting;
class ClientActiveObject;
class GenericCAO;
class LocalPlayer;

/*
	The client-side environment.

	This is not thread-safe.
	Must be called from main (irrlicht) thread (uses the SceneManager)
	Client uses an environment mutex.
*/

enum ClientEnvEventType
{
	CEE_NONE,
	CEE_PLAYER_DAMAGE,
	CEE_PLAYER_BREATH
};

struct ClientEnvEvent
{
	ClientEnvEventType type;
	union {
		//struct{
		//} none;
		struct{
			u8 amount;
			bool send_to_server;
		} player_damage;
		struct{
			u16 amount;
		} player_breath;
	};
};

typedef std::unordered_map<u16, ClientActiveObject*> ClientActiveObjectMap;
class ClientEnvironment : public Environment
{
public:
	ClientEnvironment(ClientMap *map, ITextureSource *texturesource, Client *client);
	~ClientEnvironment();

	Map & getMap();
	ClientMap & getClientMap();

	Client *getGameDef() { return m_client; }
	void setScript(ClientScripting *script) { m_script = script; }

	void step(f32 dtime);

	virtual void setLocalPlayer(LocalPlayer *player);
	LocalPlayer *getLocalPlayer() { return m_local_player; }

	/*
		ClientSimpleObjects
	*/

	void addSimpleObject(ClientSimpleObject *simple);

	/*
		ActiveObjects
	*/

	GenericCAO* getGenericCAO(u16 id);
	ClientActiveObject* getActiveObject(u16 id);

	/*
		Adds an active object to the environment.
		Environment handles deletion of object.
		Object may be deleted by environment immediately.
		If id of object is 0, assigns a free id to it.
		Returns the id of the object.
		Returns 0 if not added and thus deleted.
	*/
	u16 addActiveObject(ClientActiveObject *object);

	void addActiveObject(u16 id, u8 type, const std::string &init_data);
	void removeActiveObject(u16 id);

	void processActiveObjectMessage(u16 id, const std::string &data);

	/*
		Callbacks for activeobjects
	*/

	void damageLocalPlayer(u8 damage, bool handle_hp=true);
	void updateLocalPlayerBreath(u16 breath);

	/*
		Client likes to call these
	*/

	// Get all nearby objects
	void getActiveObjects(v3f origin, f32 max_d,
		std::vector<DistanceSortedActiveObject> &dest);

	bool hasClientEnvEvents() const { return !m_client_event_queue.empty(); }

	// Get event from queue. If queue is empty, it triggers an assertion failure.
	ClientEnvEvent getClientEnvEvent();

	virtual void getSelectedActiveObjects(
		const core::line3d<f32> &shootline_on_map,
		std::vector<PointedThing> &objects
	);

	u16 attachement_parent_ids[USHRT_MAX + 1];

	const std::list<std::string> &getPlayerNames() { return m_player_names; }
	void addPlayerName(const std::string &name) { m_player_names.push_back(name); }
	void removePlayerName(const std::string &name) { m_player_names.remove(name); }
	void updateCameraOffset(const v3s16 &camera_offset)
	{ m_camera_offset = camera_offset; }
	v3s16 getCameraOffset() const { return m_camera_offset; }
private:
	ClientMap *m_map;
	LocalPlayer *m_local_player = nullptr;
	ITextureSource *m_texturesource;
	Client *m_client;
	ClientScripting *m_script = nullptr;
	ClientActiveObjectMap m_active_objects;
	std::vector<ClientSimpleObject*> m_simple_objects;
	std::queue<ClientEnvEvent> m_client_event_queue;
	IntervalLimiter m_active_object_light_update_interval;
	IntervalLimiter m_lava_hurt_interval;
	IntervalLimiter m_drowning_interval;
	IntervalLimiter m_breathing_interval;
	std::list<std::string> m_player_names;
	v3s16 m_camera_offset;
};
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/*
Minetest
Copyright (C) 2010-2015 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
Copyright (C) 2010-2015 celeron55, Perttu Ahola <celeron55@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#include "mapgen.h"
#include "voxel.h"
#include "noise.h"
#include "gamedef.h"
#include "mg_biome.h"
#include "mapblock.h"
#include "mapnode.h"
#include "map.h"
#include "content_sao.h"
#include "nodedef.h"
#include "emerge.h"
#include "voxelalgorithms.h"
#include "porting.h"
#include "profiler.h"
#include "settings.h"
#include "treegen.h"
#include "serialization.h"
#include "util/serialize.h"
#include "util/numeric.h"
#include "filesys.h"
#include "log.h"
#include "mapgen_flat.h"
#include "mapgen_fractal.h"
#include "mapgen_v5.h"
#include "mapgen_v6.h"
#include "mapgen_v7.h"
#include "mapgen_valleys.h"
#include "mapgen_singlenode.h"
#include "cavegen.h"
#include "dungeongen.h"

FlagDesc flagdesc_mapgen[] = {
	{"caves",       MG_CAVES},
	{"dungeons",    MG_DUNGEONS},
	{"light",       MG_LIGHT},
	{"decorations", MG_DECORATIONS},
	{NULL,       0}
};

FlagDesc flagdesc_gennotify[] = {
	{"dungeon",          1 << GENNOTIFY_DUNGEON},
	{"temple",           1 << GENNOTIFY_TEMPLE},
	{"cave_begin",       1 << GENNOTIFY_CAVE_BEGIN},
	{"cave_end",         1 << GENNOTIFY_CAVE_END},
	{"large_cave_begin", 1 << GENNOTIFY_LARGECAVE_BEGIN},
	{"large_cave_end",   1 << GENNOTIFY_LARGECAVE_END},
	{"decoration",       1 << GENNOTIFY_DECORATION},
	{NULL,               0}
};

struct MapgenDesc {
	const char *name;
	bool is_user_visible;
};

////
//// Built-in mapgens
////

static MapgenDesc g_reg_mapgens[] = {
	{"v5",         true},
	{"v6",         true},
	{"v7",         true},
	{"flat",       true},
	{"fractal",    true},
	{"valleys",    true},
	{"singlenode", false},
};

STATIC_ASSERT(
	ARRLEN(g_reg_mapgens) == MAPGEN_INVALID,
	registered_mapgens_is_wrong_size);

////
//// Mapgen
////

Mapgen::Mapgen()
{
	generating  = false;
	id          = -1;
	seed        = 0;
	water_level = 0;
	flags       = 0;

	vm        = NULL;
	ndef      = NULL;
	biomegen  = NULL;
	biomemap  = NULL;
	heightmap = NULL;
}


Mapgen::Mapgen(int mapgenid, MapgenParams *params, EmergeManager *emerge) :
	gennotify(emerge->gen_notify_on, &emerge->gen_notify_on_deco_ids)
{
	generating  = false;
	id          = mapgenid;
	water_level = params->water_level;
	flags       = params->flags;
	csize       = v3s16(1, 1, 1) * (params->chunksize * MAP_BLOCKSIZE);

	/*
		We are losing half our entropy by doing this, but it is necessary to
		preserve reverse compatibility.  If the top half of our current 64 bit
		seeds ever starts getting used, existing worlds will break due to a
		different hash outcome and no way to differentiate between versions.

		A solution could be to add a new bit to designate that the top half of
		the seed value should be used, essentially a 1-bit version code, but
		this would require increasing the total size of a seed to 9 bytes (yuck)

		It's probably okay if this never gets fixed.  4.2 billion possibilities
		ought to be enough for anyone.
	*/
	seed = (s32)params->seed;

	vm        = NULL;
	ndef      = emerge->ndef;
	biomegen  = NULL;
	biomemap  = NULL;
	heightmap = NULL;
}


Mapgen::~Mapgen()
{
}


MapgenType Mapgen::getMapgenType(const std::string &mgname)
{
	for (size_t i = 0; i != ARRLEN(g_reg_mapgens); i++) {
		if (mgname == g_reg_mapgens[i].name)
			return (MapgenType)i;
	}

	return MAPGEN_INVALID;
}


const char *Mapgen::getMapgenName(MapgenType mgtype)
{
	size_t index = (size_t)mgtype;
	if (index == MAPGEN_INVALID || index >= ARRLEN(g_reg_mapgens))
		return "invalid";

	return g_reg_mapgens[index].name;
}


Mapgen *Mapgen::createMapgen(MapgenType mgtype, int mgid,
	MapgenParams *params, EmergeManager *emerge)
{
	switch (mgtype) {
	case MAPGEN_FLAT:
		return new MapgenFlat(mgid, (MapgenFlatParams *)params, emerge);
	case MAPGEN_FRACTAL:
		return new MapgenFractal(mgid, (MapgenFractalParams *)params, emerge);
	case MAPGEN_SINGLENODE:
		return new MapgenSinglenode(mgid, (MapgenSinglenodeParams *)params, emerge);
	case MAPGEN_V5:
		return new MapgenV5(mgid, (MapgenV5Params *)params, emerge);
	case MAPGEN_V6:
		return new MapgenV6(mgid, (MapgenV6Params *)params, emerge);
	case MAPGEN_V7:
		return new MapgenV7(mgid, (MapgenV7Params *)params, emerge);
	case MAPGEN_VALLEYS:
		return new MapgenValleys(mgid, (MapgenValleysParams *)params, emerge);
	default:
		return NULL;
	}
}


MapgenParams *Mapgen::createMapgenParams(MapgenType mgtype)
{
	switch (mgtype) {
	case MAPGEN_FLAT:
		return new MapgenFlatParams;
	case MAPGEN_FRACTAL:
		return new MapgenFractalParams;
	case MAPGEN_SINGLENODE:
		return new MapgenSinglenodeParams;
	case MAPGEN_V5:
		return new MapgenV5Params;
	case MAPGEN_V6:
		return new MapgenV6Params;
	case MAPGEN_V7:
		return new MapgenV7Params;
	case MAPGEN_VALLEYS:
		return new MapgenValleysParams;
	default:
		return NULL;
	}
}


void Mapgen::getMapgenNames(std::vector<const char *> *mgnames, bool include_hidden)
{
	for (u32 i = 0; i != ARRLEN(g_reg_mapgens); i++) {
		if (include_hidden || g_reg_mapgens[i].is_user_visible)
			mgnames->push_back(g_reg_mapgens[i].name);
	}
}


u32 Mapgen::getBlockSeed(v3s16 p, s32 seed)
{
	return (u32)seed   +
		p.Z * 38134234 +
		p.Y * 42123    +
		p.X * 23;
}


u32 Mapgen::getBlockSeed2(v3s16 p, s32 seed)
{
	u32 n = 1619 * p.X + 31337 * p.Y + 52591 * p.Z + 1013 * seed;
	n = (n >> 13) ^ n;
	return (n * (n * n * 60493 + 19990303) + 1376312589);
}


// Returns Y one under area minimum if not found
s16 Mapgen::findGroundLevelFull(v2s16 p2d)
{
	v3s16 em = vm->m_area.getExtent();
	s16 y_nodes_max = vm->m_area.MaxEdge.Y;
	s16 y_nodes_min = vm->m_area.MinEdge.Y;
	u32 i = vm->m_area.index(p2d.X, y_nodes_max, p2d.Y);
	s16 y;

	for (y = y_nodes_max; y >= y_nodes_min; y--) {
		MapNode &n = vm->m_data[i];
		if (ndef->get(n).walkable)
			break;

		vm->m_area.add_y(em, i, -1);
	}
	return (y >= y_nodes_min) ? y : y_nodes_min - 1;
}


// Returns -MAX_MAP_GENERATION_LIMIT if not found
s16 Mapgen::findGroundLevel(v2s16 p2d, s16 ymin, s16 ymax)
{
	v3s16 em = vm->m_area.getExtent();
	u32 i = vm->m_area.index(p2d.X, ymax, p2d.Y);
	s16 y;

	for (y = ymax; y >= ymin; y--) {
		MapNode &n = vm->m_data[i];
		if (ndef->get(n).walkable)
			break;

		vm->m_area.add_y(em, i, -1);
	}
	return (y >= ymin) ? y : -MAX_MAP_GENERATION_LIMIT;
}


// Returns -MAX_MAP_GENERATION_LIMIT if not found or if ground is found first
s16 Mapgen::findLiquidSurface(v2s16 p2d, s16 ymin, s16 ymax)
{
	v3s16 em = vm->m_area.getExtent();
	u32 i = vm->m_area.index(p2d.X, ymax, p2d.Y);
	s16 y;

	for (y = ymax; y >= ymin; y--) {
		MapNode &n = vm->m_data[i];
		if (ndef->get(n).walkable)
			return -MAX_MAP_GENERATION_LIMIT;
		else if (ndef->get(n).isLiquid())
			break;

		vm->m_area.add_y(em, i, -1);
	}
	return (y >= ymin) ? y : -MAX_MAP_GENERATION_LIMIT;
}


void Mapgen::updateHeightmap(v3s16 nmin, v3s16 nmax)
{
	if (!heightmap)
		return;

	//TimeTaker t("Mapgen::updateHeightmap", NULL, PRECISION_MICRO);
	int index = 0;
	for (s16 z = nmin.Z; z <= nmax.Z; z++) {
		for (s16 x = nmin.X; x <= nmax.X; x++, index++) {
			s16 y = findGroundLevel(v2s16(x, z), nmin.Y, nmax.Y);

			heightmap[index] = y;
		}
	}
	//printf("updateHeightmap: %dus\n", t.stop());
}

inline bool Mapgen::isLiquidHorizontallyFlowable(u32 vi, v3s16 em)
{
	u32 vi_neg_x = vi;
	vm->m_area.add_x(em, vi_neg_x, -1);
	if (vm->m_data[vi_neg_x].getContent() != CONTENT_IGNORE) {
		const ContentFeatures &c_nx = ndef->get(vm->m_data[vi_neg_x]);
		if (c_nx.floodable && !c_nx.isLiquid())
			return true;
	}
	u32 vi_pos_x = vi;
	vm->m_area.add_x(em, vi_pos_x, +1);
	if (vm->m_data[vi_pos_x].getContent() != CONTENT_IGNORE) {
		const ContentFeatures &c_px = ndef->get(vm->m_data[vi_pos_x]);
		if (c_px.floodable && !c_px.isLiquid())
			return true;
	}
	u32 vi_neg_z = vi;
	vm->m_area.add_z(em, vi_neg_z, -1);
	if (vm->m_data[vi_neg_z].getContent() != CONTENT_IGNORE) {
		const ContentFeatures &c_nz = ndef->get(vm->m_data[vi_neg_z]);
		if (c_nz.floodable && !c_nz.isLiquid())
			return true;
	}
	u32 vi_pos_z = vi;
	vm->m_area.add_z(em, vi_pos_z, +1);
	if (vm->m_data[vi_pos_z].getContent() != CONTENT_IGNORE) {
		const ContentFeatures &c_pz = ndef->get(vm->m_data[vi_pos_z]);
		if (c_pz.floodable && !c_pz.isLiquid())
			return true;
	}
	return false;
}

void Mapgen::updateLiquid(UniqueQueue<v3s16> *trans_liquid, v3s16 nmin, v3s16 nmax)
{
	bool isignored, isliquid, wasignored, wasliquid, waschecked, waspushed;
	v3s16 em  = vm->m_area.getExtent();

	for (s16 z = nmin.Z + 1; z <= nmax.Z - 1; z++)
	for (s16 x = nmin.X + 1; x <= nmax.X - 1; x++) {
		wasignored = true;
		wasliquid = false;
		waschecked = false;
		waspushed = false;

		u32 vi = vm->m_area.index(x, nmax.Y, z);
		for (s16 y = nmax.Y; y >= nmin.Y; y--) {
			isignored = vm->m_data[vi].getContent() == CONTENT_IGNORE;
			isliquid = ndef->get(vm->m_data[vi]).isLiquid();

			if (isignored || wasignored || isliquid == wasliquid) {
				// Neither topmost node of liquid column nor topmost node below column
				waschecked = false;
				waspushed = false;
			} else if (isliquid) {
				// This is the topmost node in the column
				bool ispushed = false;
				if (isLiquidHorizontallyFlowable(vi, em)) {
					trans_liquid->push_back(v3s16(x, y, z));
					ispushed = true;
				}
				// Remember waschecked and waspushed to avoid repeated
				// checks/pushes in case the column consists of only this node
				waschecked = true;
				waspushed = ispushed;
			} else {
				// This is the topmost node below a liquid column
				u32 vi_above = vi;
				vm->m_area.add_y(em, vi_above, 1);
				if (!waspushed && (ndef->get(vm->m_data[vi]).floodable ||
						(!waschecked && isLiquidHorizontallyFlowable(vi_above, em)))) {
					// Push back the lowest node in the column which is one
					// node above this one
					trans_liquid->push_back(v3s16(x, y + 1, z));
				}
			}

			wasliquid = isliquid;
			wasignored = isignored;
			vm->m_area.add_y(em, vi, -1);
		}
	}
}


void Mapgen::setLighting(u8 light, v3s16 nmin, v3s16 nmax)
{
	ScopeProfiler sp(g_profiler, "EmergeThread: mapgen lighting update", SPT_AVG);
	VoxelArea a(nmin, nmax);

	for (int z = a.MinEdge.Z; z <= a.MaxEdge.Z; z++) {
		for (int y = a.MinEdge.Y; y <= a.MaxEdge.Y; y++) {
			u32 i = vm->m_area.index(a.MinEdge.X, y, z);
			for (int x = a.MinEdge.X; x <= a.MaxEdge.X; x++, i++)
				vm->m_data[i].param1 = light;
		}
	}
}


void Mapgen::lightSpread(VoxelArea &a, v3s16 p, u8 light)
{
	if (light <= 1 || !a.contains(p))
		return;

	u32 vi = vm->m_area.index(p);
	MapNode &n = vm->m_data[vi];

	// Decay light in each of the banks separately
	u8 light_day = light & 0x0F;
	if (light_day > 0)
		light_day -= 0x01;

	u8 light_night = light & 0xF0;
	if (light_night > 0)
		light_night -= 0x10;

	// Bail out only if we have no more light from either bank to propogate, or
	// we hit a solid block that light cannot pass through.
	if ((light_day  <= (n.param1 & 0x0F) &&
		light_night <= (n.param1 & 0xF0)) ||
		!ndef->get(n).light_propagates)
		return;

	// Since this recursive function only terminates when there is no light from
	// either bank left, we need to take the max of both banks into account for
	// the case where spreading has stopped for one light bank but not the other.
	light = MYMAX(light_day, n.param1 & 0x0F) |
			MYMAX(light_night, n.param1 & 0xF0);

	n.param1 = light;

	lightSpread(a, p + v3s16(0, 0, 1), light);
	lightSpread(a, p + v3s16(0, 1, 0), light);
	lightSpread(a, p + v3s16(1, 0, 0), light);
	lightSpread(a, p - v3s16(0, 0, 1), light);
	lightSpread(a, p - v3s16(0, 1, 0), light);
	lightSpread(a, p - v3s16(1, 0, 0), light);
}


void Mapgen::calcLighting(v3s16 nmin, v3s16 nmax, v3s16 full_nmin, v3s16 full_nmax,
	bool propagate_shadow)
{
	ScopeProfiler sp(g_profiler, "EmergeThread: mapgen lighting update", SPT_AVG);
	//TimeTaker t("updateLighting");

	propagateSunlight(nmin, nmax, propagate_shadow);
	spreadLight(full_nmin, full_nmax);

	//printf("updateLighting: %dms\n", t.stop());
}


void Mapgen::propagateSunlight(v3s16 nmin, v3s16 nmax, bool propagate_shadow)
{
	//TimeTaker t("propagateSunlight");
	VoxelArea a(nmin, nmax);
	bool block_is_underground = (water_level >= nmax.Y);
	v3s16 em = vm->m_area.getExtent();

	// NOTE: Direct access to the low 4 bits of param1 is okay here because,
	// by definition, sunlight will never be in the night lightbank.

	for (int z = a.MinEdge.Z; z <= a.MaxEdge.Z; z++) {
		for (int x = a.MinEdge.X; x <= a.MaxEdge.X; x++) {
			// see if we can get a light value from the overtop
			u32 i = vm->m_area.index(x, a.MaxEdge.Y + 1, z);
			if (vm->m_data[i].getContent() == CONTENT_IGNORE) {
				if (block_is_underground)
					continue;
			} else if ((vm->m_data[i].param1 & 0x0F) != LIGHT_SUN &&
					propagate_shadow) {
				continue;
			}
			vm->m_area.add_y(em, i, -1);

			for (int y = a.MaxEdge.Y; y >= a.MinEdge.Y; y--) {
				MapNode &n = vm->m_data[i];