void P_LoadLineDefs (int lump)
{
    byte*		data;
    int			i;
    maplinedef_t*	mld;
    line_t*		ld;
    vertex_t*		v1;
    vertex_t*		v2;
	
    numlines = W_LumpLength (lump) / sizeof(maplinedef_t);
    lines = Z_Malloc (numlines*sizeof(line_t),PU_LEVEL,0);	
    memset (lines, 0, numlines*sizeof(line_t));
    data = W_CacheLumpNum (lump,PU_STATIC);
	
    mld = (maplinedef_t *)data;
    ld = lines;
    for (i=0 ; i<numlines ; i++, mld++, ld++)
    {
	ld->flags = SHORT(mld->flags);
	ld->special = SHORT(mld->special);
	ld->tag = SHORT(mld->tag);
	v1 = ld->v1 = &vertexes[SHORT(mld->v1)];
	v2 = ld->v2 = &vertexes[SHORT(mld->v2)];
	ld->dx = v2->x - v1->x;
	ld->dy = v2->y - v1->y;
	
	if (!ld->dx)
	    ld->slopetype = ST_VERTICAL;
	else if (!ld->dy)
	    ld->slopetype = ST_HORIZONTAL;
	else
	{
	    if (FixedDiv (ld->dy , ld->dx) > 0)
		ld->slopetype = ST_POSITIVE;
	    else
		ld->slopetype = ST_NEGATIVE;
	}
		
	if (v1->x < v2->x)
	{
	    ld->bbox[BOXLEFT] = v1->x;
	    ld->bbox[BOXRIGHT] = v2->x;
	}
	else
	{
	    ld->bbox[BOXLEFT] = v2->x;
	    ld->bbox[BOXRIGHT] = v1->x;
	}

	if (v1->y < v2->y)
	{
	    ld->bbox[BOXBOTTOM] = v1->y;
	    ld->bbox[BOXTOP] = v2->y;
	}
	else
	{
	    ld->bbox[BOXBOTTOM] = v2->y;
	    ld->bbox[BOXTOP] = v1->y;
	}

	ld->sidenum[0] = SHORT(mld->sidenum[0]);
	ld->sidenum[1] = SHORT(mld->sidenum[1]);

	if (ld->sidenum[0] != -1)
	    ld->frontsector = sides[ld->sidenum[0]].sector;
	else
	    ld->frontsector = 0;

	if (ld->sidenum[1] != -1)
	    ld->backsector = sides[ld->sidenum[1]].sector;
	else
	    ld->backsector = 0;
    }
	
    Z_Free (data);
}

//
// P_LoadSideDefs
//
void P_LoadSideDefs (int lump)
{
    byte*		data;
    int			i;
    mapsidedef_t*	msd;
    side_t*		sd;
	
    numsides = W_LumpLength (lump) / sizeof(mapsidedef_t);
    sides = Z_Malloc (numsides*sizeof(side_t),PU_LEVEL,0);	
    memset (sides, 0, numsides*sizeof(side_t));
    data = W_CacheLumpNum (lump,PU_STATIC);
	
    msd = (mapsidedef_t *)data;
    sd = sides;
    for (i=0 ; i<numsides ; i++, msd++, sd++)
    {
	sd->textureoffset = SHORT(msd->textureoffset)<<FRACBITS;
	sd->rowoffset = SHORT(msd->rowoffset)<<FRACBITS;
	sd->toptexture = R_TextureNumForName(msd->toptexture);
	sd->bottomtexture = R_TextureNumForName(msd->bottomtexture);
	sd->midtexture = R_TextureNumForName(msd->midtexture);
	sd->sector = &sectors[SHORT(msd->sector)];
    }

    Z_Free (data);
}


//
// P_LoadBlockMap
//
void P_LoadBlockMap (int lump)
{
    int		i;
    int		count;
	
    blockmaplump = W_CacheLumpNum (lump,PU_LEVEL);
    blockmap = blockmaplump+4;
    count = W_LumpLength (lump)/2;

    for (i=0 ; i<count ; i++)
       blockmaplump[i] = SHORT(blockmaplump[i]);

    bmaporgx = blockmaplump[0]<<FRACBITS;
    bmaporgy = blockmaplump[1]<<FRACBITS;
    bmapwidth = blockmaplump[2];
    bmapheight = blockmaplump[3];
	
    // clear out mobj chains
    count = sizeof(*blocklinks)* bmapwidth*bmapheight;
    blocklinks = Z_Malloc (count,PU_LEVEL, 0);
    memset (blocklinks, 0, count);
}



//
// P_GroupLines
// Builds sector line lists and subsector sector numbers.
// Finds block bounding boxes for sectors.
//
void P_GroupLines (void)
{
    line_t**		linebuffer;
    int			i;
    int			j;
    int			total;
    line_t*		li;
    sector_t*		sector;
    subsector_t*	ss;
    seg_t*		seg;
    fixed_t		bbox[4];
    int			block;
	
    // look up sector number for each subsector
    ss = subsectors;
    for (i=0 ; i<numsubsectors ; i++, ss++)
    {
	seg = &segs[ss->firstline];
	ss->sector = seg->sidedef->sector;
    }

    // count number of lines in each sector
    li = lines;
    total = 0;
    for (i=0 ; i<numlines ; i++, li++)
    {
	total++;
	li->frontsector->linecount++;

	if (li->backsector && li->backsector != li->frontsector)
	{
	    li->backsector->linecount++;
	    total++;
	}
    }
	
    // build line tables for each sector	
    linebuffer = Z_Malloc (total*4, PU_LEVEL, 0);
    sector = sectors;
    for (i=0 ; i<numsectors ; i++, sector++)
    {
	M_ClearBox (bbox);
	sector->lines = linebuffer;
	li = lines;
	for (j=0 ; j<numlines ; j++, li++)
	{
	    if (li->frontsector == sector || li->backsector == sector)
	    {
		*linebuffer++ = li;
		M_AddToBox (bbox, li->v1->x, li->v1->y);
		M_AddToBox (bbox, li->v2->x, li->v2->y);
	    }
	}
	if (linebuffer - sector->lines != sector->linecount)
	    I_Error ("P_GroupLines: miscounted");
			
	// set the degenmobj_t to the middle of the bounding box
	sector->soundorg.x = (bbox[BOXRIGHT]+bbox[BOXLEFT])/2;
	sector->soundorg.y = (bbox[BOXTOP]+bbox[BOXBOTTOM])/2;
		
	// adjust bounding box to map blocks
	block = (bbox[BOXTOP]-bmaporgy+MAXRADIUS)>>MAPBLOCKSHIFT;
	block = block >= bmapheight ? bmapheight-1 : block;
	sector->blockbox[BOXTOP]=block;

	block = (bbox[BOXBOTTOM]-bmaporgy-MAXRADIUS)>>MAPBLOCKSHIFT;
	block = block < 0 ? 0 : block;
	sector->blockbox[BOXBOTTOM]=block;

	block = (bbox[BOXRIGHT]-bmaporgx+MAXRADIUS)>>MAPBLOCKSHIFT;
	block = block >= bmapwidth ? bmapwidth-1 : block;
	sector->blockbox[BOXRIGHT]=block;

	block = (bbox[BOXLEFT]-bmaporgx-MAXRADIUS)>>MAPBLOCKSHIFT;
	block = block < 0 ? 0 : block;
	sector->blockbox[BOXLEFT]=block;
    }
	
}

void WriteDebug(char *);

//
// P_SetupLevel
//
void
P_SetupLevel
( int		episode,
  int		map,
  int		playermask,
  skill_t	skill)
{
    int		i;
    char	lumpname[9];
    int		lumpnum;
	
    totalkills = totalitems = totalsecret = wminfo.maxfrags = 0;
    wminfo.partime = 180;
    for (i=0 ; i<MAXPLAYERS ; i++)
    {
	players[i].killcount = players[i].secretcount 
	    = players[i].itemcount = 0;
    }

    // Initial height of PointOfView
    // will be set by player think.
    players[consoleplayer].viewz = 1; 

    // Make sure all sounds are stopped before Z_FreeTags.
    S_Start ();			

    
#if 0 // UNUSED
    if (debugfile)
    {
	Z_FreeTags (PU_LEVEL, MAXINT);
	Z_FileDumpHeap (debugfile);
    }
    else
#endif
       {
	Z_FreeTags (PU_LEVEL, PU_PURGELEVEL-1);
       }


    // UNUSED W_Profile ();
    P_InitThinkers ();

    // if working with a devlopment map, reload it
    W_Reload ();			
	   
    // find map name
    if ( gamemode == commercial)
    {
	if (map<10)
	    sprintf (lumpname,"map0%i", map);
	else
	    sprintf (lumpname,"map%i", map);
    }
    else
    {
	lumpname[0] = 'E';
	lumpname[1] = '0' + episode;
	lumpname[2] = 'M';
	lumpname[3] = '0' + map;
	lumpname[4] = 0;
    }

    lumpnum = W_GetNumForName (lumpname);
	
    leveltime = 0;
	
    // note: most of this ordering is important	
    P_LoadBlockMap (lumpnum+ML_BLOCKMAP);
    P_LoadVertexes (lumpnum+ML_VERTEXES);
    P_LoadSectors (lumpnum+ML_SECTORS);
    P_LoadSideDefs (lumpnum+ML_SIDEDEFS);

    P_LoadLineDefs (lumpnum+ML_LINEDEFS);
    P_LoadSubsectors (lumpnum+ML_SSECTORS);
    P_LoadNodes (lumpnum+ML_NODES);
    P_LoadSegs (lumpnum+ML_SEGS);
	
    rejectmatrix = W_CacheLumpNum (lumpnum+ML_REJECT,PU_LEVEL);
    P_GroupLines ();

    bodyqueslot = 0;
    deathmatch_p = deathmatchstarts;
    P_LoadThings (lumpnum+ML_THINGS);
    
    // if deathmatch, randomly spawn the active players
    if (deathmatch)
    {
	for (i=0 ; i<MAXPLAYERS ; i++)
	    if (playeringame[i])
	    {
		players[i].mo = NULL;
		G_DeathMatchSpawnPlayer (i);
	    }
			
    }

    // clear special respawning que
    iquehead = iquetail = 0;		
	
    // set up world state
    P_SpawnSpecials ();
	
    // build subsector connect matrix
    //	UNUSED P_ConnectSubsectors ();

    // preload graphics
    if (precache)
       {
	R_PrecacheLevel ();
       }

    //printf ("free memory: 0x%x\n", Z_FreeMemory());

}



//
// P_Init
//
void P_Init (void)
{
    P_InitSwitchList ();
    P_InitPicAnims ();
    R_InitSprites (sprnames);
}