gzdoom/src/p_saveg.cpp

/*
** p_saveg.cpp
** Code for serializing the world state in an archive
**
**---------------------------------------------------------------------------
** Copyright 1998-2016 Randy Heit
** Copyright 2005-2016 Christoph Oelckers
** All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** 1. Redistributions of source code must retain the above copyright
**    notice, this list of conditions and the following disclaimer.
** 2. Redistributions in binary form must reproduce the above copyright
**    notice, this list of conditions and the following disclaimer in the
**    documentation and/or other materials provided with the distribution.
** 3. The name of the author may not be used to endorse or promote products
**    derived from this software without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
** OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
** IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
** NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
** THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**---------------------------------------------------------------------------
**
*/

#include "i_system.h"
#include "p_local.h"
#include "p_spec.h"

// State.
#include "d_player.h"
#include "dobject.h"
#include "doomstat.h"
#include "r_state.h"
#include "m_random.h"
#include "p_saveg.h"
#include "s_sndseq.h"
#include "v_palette.h"
#include "a_sharedglobal.h"
#include "r_data/r_interpolate.h"
#include "g_level.h"
#include "po_man.h"
#include "p_setup.h"
#include "r_data/colormaps.h"
#include "p_lnspec.h"
#include "p_acs.h"
#include "p_terrain.h"
#include "am_map.h"
#include "r_data/r_translate.h"
#include "sbar.h"
#include "r_utility.h"
#include "r_sky.h"
#include "r_renderer.h"
#include "serializer.h"
#include "g_levellocals.h"

static TStaticArray<sector_t>	loadsectors;
static TStaticArray<line_t>		loadlines;
static TStaticArray<side_t>		loadsides;


//==========================================================================
//
//
//
//==========================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, line_t &line, line_t *def)
{
	if (arc.BeginObject(key))
	{
		arc("flags", line.flags, def->flags)
			("activation", line.activation, def->activation)
			("special", line.special, def->special)
			("alpha", line.alpha, def->alpha)
			.Args("args", line.args, def->args, line.special)
			("portalindex", line.portalindex, def->portalindex)
			// Unless the map loader is changed the sidedef references will not change between map loads so there's no need to save them.
			//.Array("sides", line.sidedef, 2)
			.EndObject();
	}
	return arc;

}

//==========================================================================
//
//
//
//==========================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, side_t::part &part, side_t::part *def)
{
	if (arc.canSkip() && def != nullptr && !memcmp(&part, def, sizeof(part)))
	{
		return arc;
	}

	if (arc.BeginObject(key))
	{
		arc("xoffset", part.xOffset, def->xOffset)
			("yoffset", part.yOffset, def->yOffset)
			("xscale", part.xScale, def->xScale)
			("yscale", part.yScale, def->yScale)
			("texture", part.texture, def->texture)
			("interpolation", part.interpolation)
			.EndObject();
	}
	return arc;
}

//==========================================================================
//
//
//
//==========================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, side_t &side, side_t *def)
{
	if (arc.BeginObject(key))
	{
		arc.Array("textures", side.textures, def->textures, 3, true)
			("light", side.Light, def->Light)
			("flags", side.Flags, def->Flags)
			// These also remain identical across map loads
			//("leftside", side.LeftSide)
			//("rightside", side.RightSide)
			//("index", side.Index)
			("attacheddecals", side.AttachedDecals)
			.EndObject();
	}
	return arc;
}

//==========================================================================
//
//
//
//==========================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, FLinkedSector &ls, FLinkedSector *def)
{
	if (arc.BeginObject(key))
	{
		arc("sector", ls.Sector)
			("type", ls.Type)
			.EndObject();
	}
	return arc;
}

//==========================================================================
//
//
//
//==========================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, sector_t::splane &p, sector_t::splane *def)
{
	if (arc.canSkip() && def != nullptr && !memcmp(&p, def, sizeof(p)))
	{
		return arc;
	}

	if (arc.BeginObject(key))
	{
		arc("xoffs", p.xform.xOffs, def->xform.xOffs)
			("yoffs", p.xform.yOffs, def->xform.yOffs)
			("xscale", p.xform.xScale, def->xform.xScale)
			("yscale", p.xform.yScale, def->xform.yScale)
			("angle", p.xform.Angle, def->xform.Angle)
			("baseyoffs", p.xform.baseyOffs, def->xform.baseyOffs)
			("baseangle", p.xform.baseAngle, def->xform.baseAngle)
			("flags", p.Flags, def->Flags)
			("light", p.Light, def->Light)
			("texture", p.Texture, def->Texture)
			("texz", p.TexZ, def->TexZ)
			("alpha", p.alpha, def->alpha)
			("glowcolor", p.GlowColor, def->GlowColor)
			("glowheight", p.GlowHeight, def->GlowHeight)
			.EndObject();
	}
	return arc;
}

//==========================================================================
//
//
//
//==========================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, secplane_t &p, secplane_t *def)
{
	if (arc.canSkip() && def != nullptr && !memcmp(&p, def, sizeof(p)))
	{
		return arc;
	}

	if (arc.BeginObject(key))
	{
		Serialize(arc, "normal", p.normal, def ? &def->normal : nullptr);
		Serialize(arc, "d", p.D, def ? &def->D : nullptr);
		arc.EndObject();

		if (arc.isReading() && p.normal.Z != 0)
		{
			p.negiC = -1 / p.normal.Z;
		}
	}
	return arc;
}

//==========================================================================
//
//
//
//==========================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, sector_t &p, sector_t *def)
{
	// save the Scroll data here because it's a lot easier to handle a default.
	// Just writing out the full array can massively inflate the archive for no gain.
	DVector2 scroll = { 0,0 }, nul = { 0,0 };
	if (arc.isWriting() && level.Scrolls.Size() > 0) scroll = level.Scrolls[p.sectornum];

	if (arc.BeginObject(key))
	{
		arc("floorplane", p.floorplane, def->floorplane)
			("ceilingplane", p.ceilingplane, def->ceilingplane)
			("lightlevel", p.lightlevel, def->lightlevel)
			("special", p.special, def->special)
			("seqtype", p.seqType, def->seqType)
			("seqname", p.SeqName, def->SeqName)
			("friction", p.friction, def->friction)
			("movefactor", p.movefactor, def->movefactor)
			("stairlock", p.stairlock, def->stairlock)
			("prevsec", p.prevsec, def->prevsec)
			("nextsec", p.nextsec, def->nextsec)
			.Array("planes", p.planes, def->planes, 2, true)
			// These cannot change during play.
			//("heightsec", p.heightsec)
			//("bottommap", p.bottommap)
			//("midmap", p.midmap)
			//("topmap", p.topmap)
			("damageamount", p.damageamount, def->damageamount)
			("damageinterval", p.damageinterval, def->damageinterval)
			("leakydamage", p.leakydamage, def->leakydamage)
			("damagetype", p.damagetype, def->damagetype)
			("sky", p.sky, def->sky)
			("moreflags", p.MoreFlags, def->MoreFlags)
			("flags", p.Flags, def->Flags)
			.Array("portals", p.Portals, def->Portals, 2, true)
			("zonenumber", p.ZoneNumber, def->ZoneNumber)
			.Array("interpolations", p.interpolations, 4, true)
			("soundtarget", p.SoundTarget)
			("secacttarget", p.SecActTarget)
			("floordata", p.floordata)
			("ceilingdata", p.ceilingdata)
			("lightingdata", p.lightingdata)
			("fakefloor_sectors", p.e->FakeFloor.Sectors)
			("midtexf_lines", p.e->Midtex.Floor.AttachedLines)
			("midtexf_sectors", p.e->Midtex.Floor.AttachedSectors)
			("midtexc_lines", p.e->Midtex.Ceiling.AttachedLines)
			("midtexc_sectors", p.e->Midtex.Ceiling.AttachedSectors)
			("linked_floor", p.e->Linked.Floor.Sectors)
			("linked_ceiling", p.e->Linked.Ceiling.Sectors)
			("colormap", p.ColorMap, def->ColorMap)
			("gravity", p.gravity, def->gravity)
			.Terrain("floorterrain", p.terrainnum[0], &def->terrainnum[0])
			.Terrain("ceilingterrain", p.terrainnum[1], &def->terrainnum[1])
			("scrolls", scroll, nul)
			// GZDoom exclusive:
			.Array("reflect", p.reflect, def->reflect, 2)
			.EndObject();

		if (arc.isReading() && !scroll.isZero())
		{
			if (level.Scrolls.Size() == 0)
			{
				level.Scrolls.Resize(level.sectors.Size());
				memset(&level.Scrolls[0], 0, sizeof(level.Scrolls[0])*level.Scrolls.Size());
				level.Scrolls[p.sectornum] = scroll;
			}
		}
	}
	return arc;
}

//==========================================================================
//
// RecalculateDrawnSubsectors
//
// In case the subsector data is unusable this function tries to reconstruct
// if from the linedefs' ML_MAPPED info.
//
//==========================================================================

void RecalculateDrawnSubsectors()
{
	for (int i = 0; i<numsubsectors; i++)
	{
		subsector_t *sub = &subsectors[i];
		for (unsigned int j = 0; j<sub->numlines; j++)
		{
			if (sub->firstline[j].linedef != NULL &&
				(sub->firstline[j].linedef->flags & ML_MAPPED))
			{
				sub->flags |= SSECF_DRAWN;
			}
		}
	}
}

//==========================================================================
//
//
//
//==========================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, subsector_t *&ss, subsector_t **)
{
	BYTE by;
	const char *str;

	if (arc.isWriting())
	{
		if (hasglnodes)
		{
			TArray<char> encoded(1 + (numsubsectors + 5) / 6);
			int p = 0;
			for (int i = 0; i < numsubsectors; i += 6)
			{
				by = 0;
				for (int j = 0; j < 6; j++)
				{
					if (i + j < numsubsectors && (subsectors[i + j].flags & SSECF_DRAWN))
					{
						by |= (1 << j);
					}
				}
				if (by < 10) by += '0';
				else if (by < 36) by += 'A' - 10;
				else if (by < 62) by += 'a' - 36;
				else if (by == 62) by = '-';
				else if (by == 63) by = '+';
				encoded[p++] = by;
			}
			encoded[p] = 0;
			str = &encoded[0];
			if (arc.BeginArray(key))
			{
				auto numvertexes = level.vertexes.Size();
				arc(nullptr, numvertexes)
					(nullptr, numsubsectors)
					.StringPtr(nullptr, str)
					.EndArray();
			}
		}
	}
	else
	{
		int num_verts, num_subs;
		bool success = false;
		if (arc.BeginArray(key))
		{
			arc(nullptr, num_verts)
				(nullptr, num_subs)
				.StringPtr(nullptr, str)
				.EndArray();

			if (num_verts == (int)level.vertexes.Size() && num_subs == numsubsectors && hasglnodes)
			{
				success = true;
				int sub = 0;
				for (int i = 0; str[i] != 0; i++)
				{
					by = str[i];
					if (by >= '0' && by <= '9') by -= '0';
					else if (by >= 'A' && by <= 'Z') by -= 'A' - 10;
					else if (by >= 'a' && by <= 'z') by -= 'a' - 36;
					else if (by == '-') by = 62;
					else if (by == '+') by = 63;
					else
					{
						success = false;
						break;
					}
					for (int s = 0; s < 6; s++)
					{
						if (sub + s < numsubsectors && (by & (1 << s)))
						{
							subsectors[sub + s].flags |= SSECF_DRAWN;
						}
					}
					sub += 6;
				}
			}
			if (hasglnodes && !success)
			{
				RecalculateDrawnSubsectors();
			}
		}

	}
	return arc;
}

//============================================================================
//
// Save a line portal for savegames.
//
//============================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, FLinePortal &port, FLinePortal *def)
{
	if (arc.BeginObject(key))
	{
		arc("origin", port.mOrigin)
			("destination", port.mDestination)
			("displacement", port.mDisplacement)
			("type", port.mType)
			("flags", port.mFlags)
			("defflags", port.mDefFlags)
			("align", port.mAlign)
			.EndObject();
	}
	return arc;
}

//============================================================================
//
// Save a sector portal for savegames.
//
//============================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, FSectorPortal &port, FSectorPortal *def)
{
	if (arc.BeginObject(key))
	{
		arc("type", port.mType)
			("flags", port.mFlags)
			("partner", port.mPartner)
			("plane", port.mPlane)
			("origin", port.mOrigin)
			("destination", port.mDestination)
			("displacement", port.mDisplacement)
			("planez", port.mPlaneZ)
			("skybox", port.mSkybox)
			.EndObject();
	}
	return arc;
}

//============================================================================
//
// one polyobject.
//
//============================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, FPolyObj &poly, FPolyObj *def)
{
	if (arc.BeginObject(key))
	{
		DAngle angle = poly.Angle;
		DVector2 delta = poly.StartSpot.pos;
		arc("angle", angle)
			("pos", delta)
			("interpolation", poly.interpolation)
			("blocked", poly.bBlocked)
			("hasportals", poly.bHasPortals)
			("specialdata", poly.specialdata)
			.EndObject();

		if (arc.isReading())
		{
			poly.RotatePolyobj(angle, true);
			delta -= poly.StartSpot.pos;
			poly.MovePolyobj(delta, true);
		}
	}
	return arc;
}

//==========================================================================
//
//
//
//==========================================================================

FSerializer &Serialize(FSerializer &arc, const char *key, ReverbContainer *&c, ReverbContainer **def)
{
	int id = (arc.isReading() || c == nullptr) ? 0 : c->ID;
	Serialize(arc, key, id, nullptr);
	if (arc.isReading())
	{
		c = S_FindEnvironment(id);
	}
	return arc;
}

FSerializer &Serialize(FSerializer &arc, const char *key, zone_t &z, zone_t *def)
{
	return Serialize(arc, key, z.Environment, nullptr);
}

//==========================================================================
//
// ArchiveSounds
//
//==========================================================================

void P_SerializeSounds(FSerializer &arc)
{
	S_SerializeSounds(arc);
	DSeqNode::SerializeSequences (arc);
	const char *name = NULL;
	BYTE order;

	if (arc.isWriting())
	{
		order = S_GetMusic(&name);
	}
	arc.StringPtr("musicname", name)
		("musicorder", order);

	if (arc.isReading())
	{
		if (!S_ChangeMusic(name, order))
			if (level.cdtrack == 0 || !S_ChangeCDMusic(level.cdtrack, level.cdid))
				S_ChangeMusic(level.Music, level.musicorder);
	}
}

//==========================================================================
//
//
//
//==========================================================================

void CopyPlayer(player_t *dst, player_t *src, const char *name);
static void ReadOnePlayer(FSerializer &arc, bool skipload);
static void ReadMultiplePlayers(FSerializer &arc, int numPlayers, int numPlayersNow, bool skipload);
static void SpawnExtraPlayers();

//==========================================================================
//
// P_ArchivePlayers
//
//==========================================================================

void P_SerializePlayers(FSerializer &arc, bool skipload)
{
	int numPlayers, numPlayersNow;
	int i;

	// Count the number of players present right now.
	for (numPlayersNow = 0, i = 0; i < MAXPLAYERS; ++i)
	{
		if (playeringame[i])
		{
			++numPlayersNow;
		}
	}

	if (arc.isWriting())
	{
		// Record the number of players in this save.
		arc("numplayers", numPlayersNow);
		if (arc.BeginArray("players"))
		{
			// Record each player's name, followed by their data.
			for (i = 0; i < MAXPLAYERS; ++i)
			{
				if (playeringame[i])
				{
					if (arc.BeginObject(nullptr))
					{
						const char *n = players[i].userinfo.GetName();
						arc.StringPtr("playername", n);
						players[i].Serialize(arc);
						arc.EndObject();
					}
				}
			}
			arc.EndArray();
		}
	}
	else
	{
		arc("numplayers", numPlayers);

		if (arc.BeginArray("players"))
		{
			// If there is only one player in the game, they go to the
			// first player present, no matter what their name.
			if (numPlayers == 1)
			{
				ReadOnePlayer(arc, skipload);
			}
			else
			{
				ReadMultiplePlayers(arc, numPlayers, numPlayersNow, skipload);
			}
			arc.EndArray();
		}
		if (!skipload && numPlayersNow > numPlayers)
		{
			SpawnExtraPlayers();
		}
		// Redo pitch limits, since the spawned player has them at 0.
		players[consoleplayer].SendPitchLimits();
	}
}

//==========================================================================
//
//
//
//==========================================================================

static void ReadOnePlayer(FSerializer &arc, bool skipload)
{
	int i;
	const char *name = NULL;
	bool didIt = false;

	if (arc.BeginObject(nullptr))
	{
		arc.StringPtr("playername", name);

		for (i = 0; i < MAXPLAYERS; ++i)
		{
			if (playeringame[i])
			{
				if (!didIt)
				{
					didIt = true;
					player_t playerTemp;
					playerTemp.Serialize(arc);
					if (!skipload)
					{
						// This temp player has undefined pitch limits, so set them to something
						// that should leave the pitch stored in the savegame intact when
						// rendering. The real pitch limits will be set by P_SerializePlayers()
						// via a net command, but that won't be processed in time for a screen
						// wipe, so we need something here.
						playerTemp.MaxPitch = playerTemp.MinPitch = playerTemp.mo->Angles.Pitch;
						CopyPlayer(&players[i], &playerTemp, name);
					}
					else
					{
						// we need the player actor, so that G_FinishTravel can destroy it later.
						players[i].mo = playerTemp.mo;
					}
				}
				else
				{
					if (players[i].mo != NULL)
					{
						players[i].mo->Destroy();
						players[i].mo = NULL;
					}
				}
			}
		}
		arc.EndObject();
	}
}

//==========================================================================
//
//
//
//==========================================================================

static void ReadMultiplePlayers(FSerializer &arc, int numPlayers, int numPlayersNow, bool skipload)
{
	// For two or more players, read each player into a temporary array.
	int i, j;
	const char **nametemp = new const char *[numPlayers];
	player_t *playertemp = new player_t[numPlayers];
	BYTE *tempPlayerUsed = new BYTE[numPlayers];
	BYTE playerUsed[MAXPLAYERS];

	for (i = 0; i < numPlayers; ++i)
	{
		nametemp[i] = NULL;
		if (arc.BeginObject(nullptr))
		{
			arc.StringPtr("playername", nametemp[i]);
			playertemp[i].Serialize(arc);
			arc.EndObject();
		}
		tempPlayerUsed[i] = 0;
	}
	for (i = 0; i < MAXPLAYERS; ++i)
	{
		playerUsed[i] = playeringame[i] ? 0 : 2;
	}

	if (!skipload)
	{
		// Now try to match players from the savegame with players present
		// based on their names. If two players in the savegame have the
		// same name, then they are assigned to players in the current game
		// on a first-come, first-served basis.
		for (i = 0; i < numPlayers; ++i)
		{
			for (j = 0; j < MAXPLAYERS; ++j)
			{
				if (playerUsed[j] == 0 && stricmp(players[j].userinfo.GetName(), nametemp[i]) == 0)
				{ // Found a match, so copy our temp player to the real player
					Printf("Found player %d (%s) at %d\n", i, nametemp[i], j);
					CopyPlayer(&players[j], &playertemp[i], nametemp[i]);
					playerUsed[j] = 1;
					tempPlayerUsed[i] = 1;
					break;
				}
			}
		}

		// Any players that didn't have matching names are assigned to existing
		// players on a first-come, first-served basis.
		for (i = 0; i < numPlayers; ++i)
		{
			if (tempPlayerUsed[i] == 0)
			{
				for (j = 0; j < MAXPLAYERS; ++j)
				{
					if (playerUsed[j] == 0)
					{
						Printf("Assigned player %d (%s) to %d (%s)\n", i, nametemp[i], j, players[j].userinfo.GetName());
						CopyPlayer(&players[j], &playertemp[i], nametemp[i]);
						playerUsed[j] = 1;
						tempPlayerUsed[i] = 1;
						break;
					}
				}
			}
		}

		// Make sure any extra players don't have actors spawned yet. Happens if the players
		// present now got the same slots as they had in the save, but there are not as many
		// as there were in the save.
		for (j = 0; j < MAXPLAYERS; ++j)
		{
			if (playerUsed[j] == 0)
			{
				if (players[j].mo != NULL)
				{
					players[j].mo->Destroy();
					players[j].mo = NULL;
				}
			}
		}

		// Remove any temp players that were not used. Happens if there are fewer players
		// than there were in the save, and they got shuffled.
		for (i = 0; i < numPlayers; ++i)
		{
			if (tempPlayerUsed[i] == 0)
			{
				playertemp[i].mo->Destroy();
				playertemp[i].mo = NULL;
			}
		}
	}
	else
	{
		for (i = 0; i < MAXPLAYERS; ++i)
		{
			players[i].mo = playertemp[i].mo;
		}
	}

	delete[] tempPlayerUsed;
	delete[] playertemp;
	delete[] nametemp;
}

//==========================================================================
//
//
//
//==========================================================================

void CopyPlayer(player_t *dst, player_t *src, const char *name)
{
	// The userinfo needs to be saved for real players, but it
	// needs to come from the save for bots.
	userinfo_t uibackup;
	userinfo_t uibackup2;

	uibackup.TransferFrom(dst->userinfo);
	uibackup2.TransferFrom(src->userinfo);

	int chasecam = dst->cheats & CF_CHASECAM;	// Remember the chasecam setting
	bool attackdown = dst->attackdown;
	bool usedown = dst->usedown;


	*dst = *src;		// To avoid memory leaks at this point the userinfo in src must be empty which is taken care of by the TransferFrom call above.

	dst->cheats |= chasecam;

	if (dst->Bot != nullptr)
	{
		botinfo_t *thebot = bglobal.botinfo;
		while (thebot && stricmp(name, thebot->name))
		{
			thebot = thebot->next;
		}
		if (thebot)
		{
			thebot->inuse = BOTINUSE_Yes;
		}
		bglobal.botnum++;
		dst->userinfo.TransferFrom(uibackup2);
	}
	else
	{
		dst->userinfo.TransferFrom(uibackup);
	}
	// Validate the skin
	dst->userinfo.SkinNumChanged(R_FindSkin(skins[dst->userinfo.GetSkin()].name, dst->CurrentPlayerClass));

	// Make sure the player pawn points to the proper player struct.
	if (dst->mo != nullptr)
	{
		dst->mo->player = dst;
	}

	// Same for the psprites.
	DPSprite *pspr = dst->psprites;
	while (pspr)
	{
		pspr->Owner = dst;

		pspr = pspr->Next;
	}

	// Don't let the psprites be destroyed when src is destroyed.
	src->psprites = nullptr;

	// These 2 variables may not be overwritten.
	dst->attackdown = attackdown;
	dst->usedown = usedown;
}

//==========================================================================
//
//
//
//==========================================================================

static void SpawnExtraPlayers()
{
	// If there are more players now than there were in the savegame,
	// be sure to spawn the extra players.
	int i;

	if (deathmatch)
	{
		return;
	}

	for (i = 0; i < MAXPLAYERS; ++i)
	{
		if (playeringame[i] && players[i].mo == NULL)
		{
			players[i].playerstate = PST_ENTER;
			P_SpawnPlayer(&playerstarts[i], i, (level.flags2 & LEVEL2_PRERAISEWEAPON) ? SPF_WEAPONFULLYUP : 0);
		}
	}
}

//============================================================================
//
//
//
//============================================================================

void G_SerializeLevel(FSerializer &arc, bool hubload)
{
	int i = level.totaltime;

	if (arc.isWriting())
	{
		arc.Array("checksum", level.md5, 16);
	}
	else
	{
		// prevent bad things from happening by doing a check on the size of level arrays and the map's entire checksum.
		// The old code happily tried to load savegames with any mismatch here, often causing meaningless errors
		// deep down in the deserializer or just a crash if the few insufficient safeguards were not triggered.
		BYTE chk[16] = { 0 };
		arc.Array("checksum", chk, 16);
		if (arc.GetSize("linedefs") != level.lines.Size() ||
			arc.GetSize("sidedefs") != level.sides.Size() ||
			arc.GetSize("sectors") != level.sectors.Size() ||
			arc.GetSize("polyobjs") != (unsigned)po_NumPolyobjs ||
			memcmp(chk, level.md5, 16))
		{
			I_Error("Savegame is from a different level");
		}
	}
	arc("saveversion", SaveVersion);

	Renderer->StartSerialize(arc);
	if (arc.isReading())
	{
		DThinker::DestroyAllThinkers();
		interpolator.ClearInterpolations();
		arc.ReadObjects(hubload);
	}

	arc("level.flags", level.flags)
		("level.flags2", level.flags2)
		("level.fadeto", level.fadeto)
		("level.found_secrets", level.found_secrets)
		("level.found_items", level.found_items)
		("level.killed_monsters", level.killed_monsters)
		("level.total_secrets", level.total_secrets)
		("level.total_items", level.total_items)
		("level.total_monsters", level.total_monsters)
		("level.gravity", level.gravity)
		("level.aircontrol", level.aircontrol)
		("level.teamdamage", level.teamdamage)
		("level.maptime", level.maptime)
		("level.totaltime", i)
		("level.skytexture1", level.skytexture1)
		("level.skytexture2", level.skytexture2);

	// Hub transitions must keep the current total time
	if (!hubload)
		level.totaltime = i;

	if (arc.isReading())
	{
		sky1texture = level.skytexture1;
		sky2texture = level.skytexture2;
		R_InitSkyMap();
		G_AirControlChanged();
	}



	// fixme: This needs to ensure it reads from the correct place. Should be one once there's enough of this code converted to JSON

	FBehavior::StaticSerializeModuleStates(arc);
	// The order here is important: First world state, then portal state, then thinkers, and last polyobjects.
	arc.Array("linedefs", &level.lines[0], &loadlines[0], level.lines.Size());
	arc.Array("sidedefs", &level.sides[0], &loadsides[0], level.sides.Size());
	arc.Array("sectors", &level.sectors[0], &loadsectors[0], level.sectors.Size());
	arc("zones", Zones);
	arc("lineportals", linePortals);
	arc("sectorportals", level.sectorPortals);
	if (arc.isReading()) P_CollectLinkedPortals();

	DThinker::SerializeThinkers(arc, !hubload);
	arc.Array("polyobjs", polyobjs, po_NumPolyobjs);
	arc("subsectors", subsectors);
	StatusBar->SerializeMessages(arc);
	AM_SerializeMarkers(arc);
	FRemapTable::StaticSerializeTranslations(arc);
	FCanvasTextureInfo::Serialize(arc);
	P_SerializePlayers(arc, hubload);
	P_SerializeSounds(arc);

	if (arc.isReading())
	{
		for (auto &sec : level.sectors)
		{
			P_Recalculate3DFloors(&sec);
		}
		for (int i = 0; i < MAXPLAYERS; ++i)
		{
			if (playeringame[i] && players[i].mo != NULL)
			{
				players[i].mo->SetupWeaponSlots();
			}
		}
	}
	Renderer->EndSerialize(arc);

}

// Create a backup of the map data so the savegame code can toss out all fields that haven't changed in order to reduce processing time and file size.

void P_BackupMapData()
{
	loadsectors = level.sectors;
	loadlines = level.lines;
	loadsides = level.sides;
}

void P_FreeMapDataBackup()
{
	loadsectors.Clear();
	loadlines.Clear();
	loadsides.Clear();
}