fteqw/engine/gl/gl_heightmap.c

#include "quakedef.h"

#ifdef TERRAIN
#include "glquake.h"
#include "shader.h"

#include "pr_common.h"

//#define STRICTEDGES	//strict (ugly) grid
#define TERRAINTHICKNESS 16
#define TERRAINACTIVESECTIONS 3000

/*
a note on networking:
By default terrain is NOT networked. This means content is loaded without networking delays.
If you wish to edit the terrain collaboratively, you can enable the mod_terrain_networked cvar.
When set, changes on the server will notify clients that a section has changed, and the client will reload it as needed.
Changes on the client WILL NOT notify the server, and will get clobbered if the change is also made on the server.
This means for editing purposes, you MUST funnel it via ssqc with your own permission checks.
It also means for explosions and local stuff, the server will merely restate changes from impacts if you do them early. BUT DO NOT CALL THE EDIT FUNCTION IF THE SERVER HAS ALREADY APPLIED THE CHANGE.
*/
cvar_t mod_terrain_networked = CVARD("mod_terrain_networked", "0", "Terrain edits are networked. Clients will download sections on demand, and servers will notify clients of changes.");
cvar_t mod_terrain_defaulttexture = CVARD("mod_terrain_defaulttexture", "", "Newly created terrain tiles will use this texture. This should generally be updated by the terrain editor.");
cvar_t mod_terrain_savever = CVARD("mod_terrain_savever", "", "Which terrain section version to write if terrain was edited.");

/*
terminology:
tile:
	a single grid tile of 2*2 height samples.
	iterrated for collisions but otherwise unused.
section:
	16*16 tiles, with a single texture spread over them.
	samples have an overlap with the neighbouring section (so 17*17 height samples). texture samples do not quite match height frequency (63*63 vs 16*16).
	smallest unit for culling.
block:
	16*16 sections. forms a single disk file. used only to avoid 16777216 files in a single directory, instead getting 65536 files for a single fully populated map... much smaller...
	each block file is about 4mb each. larger can be detrimental to automatic downloads.
cluster:
	64*64 sections
	internal concept to avoid a single pointer array of 16 million entries per terrain.
*/

int Surf_NewLightmaps(int count, int width, int height, qboolean deluxe);

#define MAXCLUSTERS 64
#define MAXSECTIONS 64	//this many sections within each cluster in each direction
#define SECTHEIGHTSIZE 17 //this many height samples per section
#define SECTTEXSIZE 64	//this many texture samples per section
#define SECTIONSPERBLOCK 16

//each section is this many sections higher in world space, to keep the middle centered at '0 0'
#define CHUNKBIAS	(MAXCLUSTERS*MAXSECTIONS/2)
#define CHUNKLIMIT	(MAXCLUSTERS*MAXSECTIONS)

#define LMCHUNKS 8//(LMBLOCK_WIDTH/SECTTEXSIZE)

#define HMLMSTRIDE (LMCHUNKS*SECTTEXSIZE)

#define SECTION_MAGIC (*(int*)"HMMS")
#define SECTION_VER_DEFAULT	1
/*simple version history:
ver=0
	SECTHEIGHTSIZE=16
ver=1
	SECTHEIGHTSIZE=17 (oops, makes holes more usable)
	(holes in this format are no longer supported)
ver=2
	uses deltas instead of absolute values
	variable length image names
*/

#define TGS_NOLOAD			0
#define TGS_LOAD			1	//always try to load it.
#define TGS_FORCELOAD		2	//load it even if it doesn't exist (for editing). will otherwise be unusable
#define TGS_LAZYLOAD		4	//only try to load it if its the only one we loaded this frame.
#define TGS_NODOWNLOAD		8	//don't queue it for download
#define TGS_NORENDER		16	//don't upload any textures or whatever
#define TGS_IGNOREFAILED	32	//grab the section even if its invalid, used for loading/overwriting 

enum
{
	//these flags can be found on disk
	TSF_HASWATER_V0	= 1u<<0,	//no longer flagged.
	TSF_HASCOLOURS	= 1u<<1,
	TSF_HASHEIGHTS	= 1u<<2,
	TSF_HASSHADOW	= 1u<<3,

	//these flags are found only on disk
	TSF_COMPRESSED	= 1u<<31,

	//these flags should not be found on disk
	TSF_FAILEDLOAD	= 1u<<27,	//placeholder to avoid excess disk access in border regions
	TSF_NOTIFY		= 1u<<28,	//modified on server, waiting for clients to be told about the change.
	TSF_RELIGHT		= 1u<<29,	//height edited, needs relighting.
	TSF_DIRTY		= 1u<<30,	//its heightmap has changed, the mesh needs rebuilding
	TSF_EDITED		= 1u<<31	//says it needs to be written if saved

#define TSF_INTERNAL	(TSF_RELIGHT|TSF_DIRTY|TSF_EDITED|TSF_NOTIFY|TSF_FAILEDLOAD)
};
enum
{
	TMF_SCALE	= 1u<<0,
	//what else do we want? alpha? colormod perhaps?
};

typedef struct
{
	int size;
	vec3_t axisorg[4];
	float scale;
	int reserved3;
	int reserved2;
	int reserved1;
	//char modelname[1+];
} dsmesh_t;

typedef struct
{
	unsigned int flags;
	char texname[4][32];
	unsigned int texmap[SECTTEXSIZE][SECTTEXSIZE];
	float heights[SECTHEIGHTSIZE*SECTHEIGHTSIZE];
	unsigned short holes;
	unsigned short reserved0;
	float waterheight;
	float minh;
	float maxh;
	int ents_num;
	int reserved1;
	int reserved4;
	int reserved3;
	int reserved2;
} dsection_v1_t;

//file header for a single section
typedef struct
{
	int magic;
	int ver;
} dsection_t;

//file header for a block of sections.
//(because 16777216 files in a single directory is a bad plan. windows really doesn't like it.)
typedef struct
{
	//a block is a X*Y group of sections
	//if offset==0, the section isn't present.
	//the data length of the section preceeds the actual data.
	int magic;
	int ver;
	unsigned int offset[SECTIONSPERBLOCK*SECTIONSPERBLOCK];
} dblock_t;

typedef struct hmpolyset_s
{
	struct hmpolyset_s *next;
	shader_t *shader;
	mesh_t mesh;
	mesh_t *amesh;
	vbo_t vbo;
} hmpolyset_t;
struct hmwater_s
{
	struct hmwater_s *next;
	unsigned int contentmask;
	qboolean simple;	//no holes, one height
	float minheight;
	float maxheight;
	shader_t *shader;
	qbyte holes[8];
	float heights[9*9];
};
typedef struct
{
	link_t recycle;
	int sx, sy;

	float heights[SECTHEIGHTSIZE*SECTHEIGHTSIZE];
	unsigned char holes[8];
	unsigned int flags;
	float maxh_cull;	//includes water+mesh heights
	float minh, maxh;
	struct heightmap_s *hmmod;

	struct hmwater_s *water;

#ifndef SERVERONLY
	pvscache_t pvscache;
	vec4_t colours[SECTHEIGHTSIZE*SECTHEIGHTSIZE];	//FIXME: make bytes
	char texname[4][MAX_QPATH];
	int lightmap;
	int lmx, lmy;

	texnums_t textures;
	vbo_t vbo;
	mesh_t mesh;
	mesh_t *amesh;

	int numents;
	int maxents;
	entity_t *ents;

	hmpolyset_t *polys;
#endif
} hmsection_t;
typedef struct
{
	hmsection_t *section[MAXSECTIONS*MAXSECTIONS];
} hmcluster_t;
typedef struct heightmap_s
{
	char path[MAX_QPATH];
	char watershadername[MAX_QPATH];	//typically the name of the ocean or whatever.
	int firstsegx, firstsegy;
	int maxsegx, maxsegy; //tex/cull sections
	float sectionsize;	//each section is this big, in world coords
	hmcluster_t *cluster[MAXCLUSTERS*MAXCLUSTERS];
	shader_t *skyshader;
	shader_t *shader;
	mesh_t skymesh;
	mesh_t *askymesh;
	unsigned int exteriorcontents;
	qboolean beinglazy;	//only load one section per frame, if its the renderer doing the loading. this helps avoid stalls, in theory.
	enum
	{
		HMM_TERRAIN,
		HMM_BLOCKS
	} mode;
	int tilecount[2];
	int tilepixcount[2];

	int activesections;
	link_t recycle;		//section list in lru order
//	link_t collected;	//memory that may be reused, to avoid excess reallocs.

#ifndef SERVERONLY
	unsigned int numusedlmsects;	//to track leaks and stats
	unsigned int numunusedlmsects;
	struct lmsect_s
	{
		struct lmsect_s *next;
		int lm, x, y;
	} *unusedlmsects;
#endif

#ifndef SERVERONLY
	//I'm putting this here because we might have some quite expensive lighting routines going on
	//and that'll make editing the terrain jerky as fook, so relighting it a few texels at a time will help maintain a framerate while editing
	hmsection_t *relight;
	unsigned int relightidx;
	vec2_t relightmin;
#endif
} heightmap_t;

#ifndef SERVERONLY
static void ted_dorelight(heightmap_t *hm);
#endif
static qboolean Terr_Collect(heightmap_t *hm);
static hmsection_t *Terr_GetSection(heightmap_t *hm, int x, int y, unsigned int flags);

#ifndef SERVERONLY
static texid_t Terr_LoadTexture(char *name)
{
	extern texid_t missing_texture;
	texid_t id;
	if (*name)
	{
		id = R_LoadHiResTexture(name, NULL, 0);
		if (!TEXVALID(id))
		{
			id = missing_texture;
			Con_Printf("Unable to load texture %s\n", name);
		}
	}
	else
		id = missing_texture;
	return id;
}
#endif

static void Terr_LoadSectionTextures(hmsection_t *s)
{
#ifndef SERVERONLY
	extern texid_t missing_texture;
	if (isDedicated)
		return;
	//CL_CheckOrEnqueDownloadFile(s->texname[0], NULL, 0);
	//CL_CheckOrEnqueDownloadFile(s->texname[1], NULL, 0);
	//CL_CheckOrEnqueDownloadFile(s->texname[2], NULL, 0);
	//CL_CheckOrEnqueDownloadFile(s->texname[3], NULL, 0);
	switch(s->hmmod->mode)
	{
	case HMM_BLOCKS:
		s->textures.base			= Terr_LoadTexture(va("maps/%s/atlas.tga", s->hmmod->path));
		s->textures.fullbright		= Terr_LoadTexture(va("maps/%s/atlas_luma.tga", s->hmmod->path));
		s->textures.bump			= Terr_LoadTexture(va("maps/%s/atlas_norm.tga", s->hmmod->path));
		s->textures.specular		= Terr_LoadTexture(va("maps/%s/atlas_spec.tga", s->hmmod->path));
		s->textures.upperoverlay	= missing_texture;
		s->textures.loweroverlay	= missing_texture;
		break;
	case HMM_TERRAIN:
		s->textures.base			= Terr_LoadTexture(s->texname[0]);
		s->textures.upperoverlay	= Terr_LoadTexture(s->texname[1]);
		s->textures.loweroverlay	= Terr_LoadTexture(s->texname[2]);
		s->textures.fullbright		= Terr_LoadTexture(s->texname[3]);
		s->textures.bump			= *s->texname[0]?R_LoadHiResTexture(va("%s_norm", s->texname[0]), NULL, 0):r_nulltex;
		s->textures.specular		= *s->texname[0]?R_LoadHiResTexture(va("%s_spec", s->texname[0]), NULL, 0):r_nulltex;
		break;
	}
#endif
}

#ifndef SERVERONLY
static qboolean Terr_InitLightmap(hmsection_t *s, qboolean initialise)
{
	heightmap_t *hm = s->hmmod;

	if (s->lightmap < 0)
	{
		struct lmsect_s *lms;
		if (!hm->unusedlmsects)
		{
			int lm;
			int i;
			lm = Surf_NewLightmaps(1, SECTTEXSIZE*LMCHUNKS, SECTTEXSIZE*LMCHUNKS, false);
			for (i = 0; i < LMCHUNKS*LMCHUNKS; i++)
			{
				lms = BZ_Malloc(sizeof(*lms));
				lms->lm = lm;
				lms->x = (i & (LMCHUNKS-1))*SECTTEXSIZE;
				lms->y = (i / LMCHUNKS)*SECTTEXSIZE;
				lms->next = hm->unusedlmsects;
				hm->unusedlmsects = lms;
				hm->numunusedlmsects++;
			}
		}

		lms = hm->unusedlmsects;
		hm->unusedlmsects = lms->next;
		
		s->lightmap = lms->lm;
		s->lmx = lms->x;
		s->lmy = lms->y;

		hm->numunusedlmsects--;
		hm->numusedlmsects++;

		Z_Free(lms);
	}

	if (initialise && s->lightmap >= 0)
	{
		int x, y;
		unsigned char *lm;
		lm = lightmap[s->lightmap]->lightmaps;
		lm += (s->lmy * HMLMSTRIDE + s->lmx) * lightmap_bytes;
		for (y = 0; y < SECTTEXSIZE; y++)
		{
			for (x = 0; x < SECTTEXSIZE; x++)
			{
				lm[x*4+0] = 0;
				lm[x*4+1] = 0;
				lm[x*4+2] = 0;
				lm[x*4+3] = 255;
			}
			lm += (HMLMSTRIDE)*lightmap_bytes;
		}

		lightmap[s->lightmap]->modified = true;
		lightmap[s->lightmap]->rectchange.l = 0;
		lightmap[s->lightmap]->rectchange.t = 0;
		lightmap[s->lightmap]->rectchange.w = HMLMSTRIDE;
		lightmap[s->lightmap]->rectchange.h = HMLMSTRIDE;
	}

	if (s->lightmap >= 0)
	{
		lightmap[s->lightmap]->modified = true;
		lightmap[s->lightmap]->rectchange.l = 0;
		lightmap[s->lightmap]->rectchange.t = 0;
		lightmap[s->lightmap]->rectchange.w = HMLMSTRIDE;
		lightmap[s->lightmap]->rectchange.h = HMLMSTRIDE;
	}

	return s->lightmap>=0;
}
#endif

char *genextendedhex(int n, char *buf)
{
	char *ret;
	static char nibble[16] = "0123456789abcdef";
	unsigned int m;
	int i;
	for (i = 7; i >= 1; i--)	//>=1 ensures at least two nibbles appear.
	{
		m = 0xfffffff8<<(i*4);
		if ((n & m) != m && (n & m) != 0)
			break;
	}
	ret = buf;
	for(i++; i >= 0; i--)
		*buf++ = nibble[(n>>i*4) & 0xf];
	*buf++ = 0;
	return ret;
}
static char *Terr_DiskBlockName(heightmap_t *hm, int sx, int sy)
{
	char xpart[9];
	char ypart[9];
	//using a naming scheme centered around 0 means we can gracefully expand the map away from 0,0
	sx -= CHUNKBIAS;
	sy -= CHUNKBIAS;
	//wrap cleanly
	sx &= CHUNKLIMIT-1;
	sy &= CHUNKLIMIT-1;
	sx /= SECTIONSPERBLOCK;
	sy /= SECTIONSPERBLOCK;
	if (sx >= CHUNKBIAS/SECTIONSPERBLOCK)
		sx |= 0xffffff00;
	if (sy >= CHUNKBIAS/SECTIONSPERBLOCK)
		sy |= 0xffffff00;
	return va("maps/%s/block_%s_%s.hms", hm->path, genextendedhex(sx, xpart), genextendedhex(sy, ypart));
}
static char *Terr_DiskSectionName(heightmap_t *hm, int sx, int sy)
{
	sx -= CHUNKBIAS;
	sy -= CHUNKBIAS;
	//wrap cleanly
	sx &= CHUNKLIMIT-1;
	sy &= CHUNKLIMIT-1;
	return va("maps/%s/sect_%03x_%03x.hms", hm->path, sx, sy);
}
#ifndef SERVERONLY
static char *Terr_TempDiskSectionName(heightmap_t *hm, int sx, int sy)
{
	sx -= CHUNKBIAS;
	sy -= CHUNKBIAS;
	//wrap cleanly
	sx &= CHUNKLIMIT-1;
	sy &= CHUNKLIMIT-1;
	return va("temp/%s/sect_%03x_%03x.hms", hm->path, sx, sy);
}
#endif

static int dehex_e(int i, qboolean *error)
{
	if      (i >= '0' && i <= '9')
		return (i-'0');
	else if (i >= 'A' && i <= 'F')
		return (i-'A'+10);
	else if (i >= 'a' && i <= 'f')
		return (i-'a'+10);
	else
		*error = true;
	return 0;
}
static qboolean Terr_IsSectionFName(heightmap_t *hm, char *fname, int *sx, int *sy)
{
	int l;
	qboolean error = false;
	*sx = 0xdeafbeef;	//something clearly invalid
	*sy = 0xdeafbeef;

	//not this model...
	if (!hm)
		return false;

	//expect the first 5 chars to be maps/ or temp/
	fname += 5;

	l = strlen(hm->path);
	if (strncmp(fname, hm->path, l) || fname[l] != '/')
		return false;
	fname += l+1;

	//fname now has a fixed length.
	if (strlen(fname) != 16)
		return false;
	if (strncmp(fname, "sect_", 5) || fname[8] != '_' || (strcmp(fname+12, ".hms") && strcmp(fname+12, ".tmp")))
		return false;

	*sx = 0;
	*sx += dehex_e(fname[5], &error)<<8;
	*sx += dehex_e(fname[6], &error)<<4;
	*sx += dehex_e(fname[7], &error)<<0;

	*sy = 0;
	*sy += dehex_e(fname[9], &error)<<8;
	*sy += dehex_e(fname[10], &error)<<4;
	*sy += dehex_e(fname[11], &error)<<0;

	*sx += CHUNKBIAS;
	*sy += CHUNKBIAS;

	if ((unsigned)*sx >= CHUNKLIMIT)
		*sx -= CHUNKLIMIT;
	if ((unsigned)*sy >= CHUNKLIMIT)
		*sy -= CHUNKLIMIT;

	//make sure its a valid section index.
	if ((unsigned)*sx >= CHUNKLIMIT)
		return false;
	if ((unsigned)*sy >= CHUNKLIMIT)
		return false;
	return true;
}

static hmsection_t *Terr_GenerateSection(heightmap_t *hm, int sx, int sy)
{
	hmsection_t *s;
	hmcluster_t *cluster;
	int clusternum = (sx/MAXSECTIONS) + (sy/MAXSECTIONS)*MAXCLUSTERS;
	cluster = hm->cluster[clusternum];
	if (!cluster)
		cluster = hm->cluster[clusternum] = Z_Malloc(sizeof(*cluster));
	s = cluster->section[(sx%MAXSECTIONS) + (sy%MAXSECTIONS)*MAXSECTIONS];
	if (!s)
	{
		/*link_t *l;
		l = hm->collected.next;
		if (l != &hm->collected)
		{
			s = (hmsection_t*)l;
			RemoveLink(&s->recycle);
		}
		else*/
		{
			s = Z_Malloc(sizeof(*s));
			if (!s)
				return NULL;
#ifndef SERVERONLY
			s->lightmap = -1;
#endif
		}

		InsertLinkBefore(&s->recycle, &hm->recycle);
		s->sx = sx;
		s->sy = sy;
		cluster->section[(sx%MAXSECTIONS) + (sy%MAXSECTIONS)*MAXSECTIONS] = s;
		hm->activesections++;
		s->hmmod = hm;
	}
#ifndef SERVERONLY
	s->numents = 0;
#endif
	s->flags = TSF_DIRTY;
	return s;
}

static void *Terr_GenerateWater(hmsection_t *s, float maxheight)
{
	int i;
	struct hmwater_s *w;
	w = Z_Malloc(sizeof(*s->water));
	w->next = s->water;
	s->water = w;
#ifndef SERVERONLY
	if (!isDedicated)
		w->shader = R_RegisterCustom (s->hmmod->watershadername, SUF_NONE, Shader_DefaultWaterShader, NULL);
#endif
	w->simple = true;
	w->contentmask = FTECONTENTS_WATER;
	memset(w->holes, 0, sizeof(w->holes));
	for (i = 0; i < 9*9; i++)
		w->heights[i] = maxheight;
	w->maxheight = w->minheight = maxheight;
	if (s->maxh_cull < w->maxheight)
		s->maxh_cull = w->maxheight;
	return w;
}

static void *Terr_ReadV1(heightmap_t *hm, hmsection_t *s, void *ptr, int len)
{
#ifndef SERVERONLY
	dsmesh_t *dm;
	float *colours;
#endif
	dsection_v1_t *ds = ptr;
	int i;

	unsigned int flags = LittleLong(ds->flags);
	s->flags |= flags & ~(TSF_INTERNAL|TSF_HASWATER_V0);
	for (i = 0; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
	{
		s->heights[i] = LittleFloat(ds->heights[i]);
	}
	s->minh = ds->minh;
	s->maxh = ds->maxh;
	if (flags & TSF_HASWATER_V0)
		Terr_GenerateWater(s, ds->waterheight);

	memset(s->holes, 0, sizeof(s->holes));
	for (i = 0; i < 8*8; i++)
	{
		int x = (i & 7);
		int y = (i>>3);
		int b = (1u<<(x>>1)) << ((y>>1)<<2);
		if (ds->holes & b)
			s->holes[y] |= 1u<<x;
	}

	ptr = ds+1;

#ifndef SERVERONLY
	/*deal with textures*/
	Q_strncpyz(s->texname[0], ds->texname[0], sizeof(s->texname[0]));
	Q_strncpyz(s->texname[1], ds->texname[1], sizeof(s->texname[1]));
	Q_strncpyz(s->texname[2], ds->texname[2], sizeof(s->texname[2]));
	Q_strncpyz(s->texname[3], ds->texname[3], sizeof(s->texname[3]));

	if (*s->texname[0])
		CL_CheckOrEnqueDownloadFile(s->texname[0], NULL, 0);
	if (*s->texname[1])
		CL_CheckOrEnqueDownloadFile(s->texname[1], NULL, 0);
	if (*s->texname[2])
		CL_CheckOrEnqueDownloadFile(s->texname[2], NULL, 0);
	if (*s->texname[3])
		CL_CheckOrEnqueDownloadFile(s->texname[3], NULL, 0);

	/*load in the mixture/lighting*/
	if (s->lightmap >= 0)
	{
		qbyte *lm;

		lm = lightmap[s->lightmap]->lightmaps;
		lm += (s->lmy * HMLMSTRIDE + s->lmx) * lightmap_bytes;
		for (i = 0; i < SECTTEXSIZE; i++)
		{
			memcpy(lm, ds->texmap + i, sizeof(ds->texmap[0]));
			lm += (HMLMSTRIDE)*lightmap_bytes;
		}
		lightmap[s->lightmap]->modified = true;
		lightmap[s->lightmap]->rectchange.l = 0;
		lightmap[s->lightmap]->rectchange.t = 0;
		lightmap[s->lightmap]->rectchange.w = HMLMSTRIDE;
		lightmap[s->lightmap]->rectchange.h = HMLMSTRIDE;
	}

	s->mesh.colors4f_array[0] = s->colours;
	if (flags & TSF_HASCOLOURS)
	{
		for (i = 0, colours = (float*)ptr; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++, colours+=4)
		{
			s->colours[i][0] = LittleFloat(colours[0]);
			s->colours[i][1] = LittleFloat(colours[1]);
			s->colours[i][2] = LittleFloat(colours[2]);
			s->colours[i][3] = LittleFloat(colours[3]);
		}
		ptr = colours;
	}
	else
	{
		for (i = 0; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
		{
			s->colours[i][0] = 1;
			s->colours[i][1] = 1;
			s->colours[i][2] = 1;
			s->colours[i][3] = 1;
		}
	}

	/*load any static ents*/
	s->numents = ds->ents_num;
	s->maxents = s->numents;
	if (s->maxents)
		s->ents = Z_Malloc(sizeof(*s->ents) * s->maxents);
	else
		s->ents = NULL;
	if (!s->ents)
		s->numents = s->maxents = 0;
	for (i = 0, dm = (dsmesh_t*)ptr; i < s->numents; i++, dm = (dsmesh_t*)((qbyte*)dm + dm->size))
	{
		s->ents[i].model = Mod_ForName((char*)(dm + 1), MLV_WARN);
		if (!s->ents[i].model || s->ents[i].model->type == mod_dummy)
		{
			s->numents--;
			i--;
			continue;
		}
		s->ents[i].scale = dm->scale;
		s->ents[i].drawflags = SCALE_ORIGIN_ORIGIN;
		s->ents[i].playerindex = -1;
		VectorCopy(dm->axisorg[0], s->ents[i].axis[0]);
		VectorCopy(dm->axisorg[1], s->ents[i].axis[1]);
		VectorCopy(dm->axisorg[2], s->ents[i].axis[2]);
		VectorCopy(dm->axisorg[3], s->ents[i].origin);
		s->ents[i].origin[0] += (s->sx-CHUNKBIAS)*hm->sectionsize;
		s->ents[i].origin[1] += (s->sy-CHUNKBIAS)*hm->sectionsize;
		s->ents[i].shaderRGBAf[0] = 1;
		s->ents[i].shaderRGBAf[1] = 1;
		s->ents[i].shaderRGBAf[2] = 1;
		s->ents[i].shaderRGBAf[3] = 1;
	}
#endif
	return ptr;
}




struct terrstream_s
{
	qbyte *buffer;
	int maxsize;
	int pos;
};
//I really hope these get inlined properly.
static int Terr_Read_SInt(struct terrstream_s *strm)
{
	int val;
	strm->pos = (strm->pos + sizeof(val)-1) & ~(sizeof(val)-1);
	val = *(int*)(strm->buffer+strm->pos);
	strm->pos += sizeof(val);
	return LittleLong(val);
}
static qbyte Terr_Read_Byte(struct terrstream_s *strm)
{
	qbyte val;
	val = *(qbyte*)(strm->buffer+strm->pos);
	strm->pos += sizeof(val);
	return val;
}
static float Terr_Read_Float(struct terrstream_s *strm)
{
	float val;
	strm->pos = (strm->pos + sizeof(val)-1) & ~(sizeof(val)-1);
	val = *(float*)(strm->buffer+strm->pos);
	strm->pos += sizeof(val);
	return LittleFloat(val);
}
static char *Terr_Read_String(struct terrstream_s *strm, char *val, int maxlen)
{
	int len = strlen(strm->buffer + strm->pos);
	maxlen = min(len, maxlen-1);	//truncate
	memcpy(val, strm->buffer + strm->pos, maxlen);
	val[maxlen] = 0;
	strm->pos += len+1;
	return val;
}
#ifndef SERVERONLY
static void Terr_Write_SInt(struct terrstream_s *strm, int val)
{
	val = LittleLong(val);
	strm->pos = (strm->pos + sizeof(val)-1) & ~(sizeof(val)-1);
	*(int*)(strm->buffer+strm->pos) = val;
	strm->pos += sizeof(val);
}
static void Terr_Write_Byte(struct terrstream_s *strm, qbyte val)
{
	*(qbyte*)(strm->buffer+strm->pos) = val;
	strm->pos += sizeof(val);
}
static void Terr_Write_Float(struct terrstream_s *strm, float val)
{
	val = LittleFloat(val);
	strm->pos = (strm->pos + sizeof(val)-1) & ~(sizeof(val)-1);
	*(float*)(strm->buffer+strm->pos) = val;
	strm->pos += sizeof(val);
}
static void Terr_Write_String(struct terrstream_s *strm, char *val)
{
	int len = strlen(val)+1;
	memcpy(strm->buffer + strm->pos, val, len);
	strm->pos += len;
}
static void Terr_TrimWater(hmsection_t *s)
{
	int i;
	struct hmwater_s *w, **link;

	for (link = &s->water; (w = *link); )
	{
		//one has a height above the terrain?
		for (i = 0; i < 9*9; i++)
			if (w->heights[i] > s->minh)
				break;
		if (i == 9*9)
		{
			*link = w->next;
			Z_Free(w);
			continue;
		}
		else
			link = &(*link)->next;
	}
}
static void Terr_SaveV2(heightmap_t *hm, hmsection_t *s, vfsfile_t *f, int sx, int sy)
{
	qbyte buffer[65536], last, delta, *lm;
	struct terrstream_s strm = {buffer, sizeof(buffer), 0};
	unsigned int flags = s->flags;
	int i, j, x, y;
	struct hmwater_s *w;

	flags &= ~(TSF_INTERNAL);
	flags &= ~(TSF_HASCOLOURS|TSF_HASHEIGHTS|TSF_HASSHADOW);

	for (i = 0; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
	{
		if (s->colours[i][0] != 1 || s->colours[i][1] != 1 || s->colours[i][2] != 1 || s->colours[i][3] != 1)
		{
			flags |= TSF_HASCOLOURS;
			break;
		}
	}
	for (i = 0; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
	{
		if (s->heights[i] != s->heights[0])
		{
			flags |= TSF_HASHEIGHTS;
			break;
		}
	}

	lm = lightmap[s->lightmap]->lightmaps;
	lm += (s->lmy * HMLMSTRIDE + s->lmx) * lightmap_bytes;
	for (y = 0; y < SECTTEXSIZE; y++)
	{
		for (x = 0; x < SECTTEXSIZE; x++)
		{
			if (lm[x*4+3] != 255)
			{
				flags |= TSF_HASSHADOW;
				y = SECTTEXSIZE;
				break;
			}
		}
		lm += (HMLMSTRIDE)*lightmap_bytes;
	}

	//write the flags so the loader knows what to load
	Terr_Write_SInt(&strm, flags);

	//if heights are compressed, only the first is present.
	if (!(flags & TSF_HASHEIGHTS))
		Terr_Write_Float(&strm, s->heights[0]);
	else
	{
		for (i = 0; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
			Terr_Write_Float(&strm, s->heights[i]);
	}

	for (i = 0; i < sizeof(s->holes); i++)
		Terr_Write_Byte(&strm, s->holes[i]);

	Terr_TrimWater(s);
	for (j = 0, w = s->water; w; j++)
		w = w->next;
	Terr_Write_SInt(&strm, j);
	for (i = 0, w = s->water; i < j; i++, w = w->next)
	{
		char *shadername = w->shader->name;
		int fl = 0;

		if (strcmp(shadername, hm->watershadername))
			fl |= 1;
		for (x = 0; x < 8; x++)
			if (w->holes[x])
				break;
		fl |= ((x==8)?0:2);
		for (x = 0; x < 9*9; x++)
			if (w->heights[x] != w->heights[0])
				break;
		fl |= ((x==9*9)?0:4);

		
		Terr_Write_SInt(&strm, fl);
		Terr_Write_SInt(&strm, w->contentmask);
		if (fl & 1)
			Terr_Write_String(&strm, shadername);
		if (fl & 2)
		{
			for (x = 0; x < 8; x++)
				Terr_Write_Byte(&strm, w->holes[x]);
		}
		if (fl & 4)
		{
			for (x = 0; x < 9*9; x++)
				Terr_Write_Float(&strm, w->heights[x]);
		}
		else
			Terr_Write_Float(&strm, w->heights[0]);
	}

	if (flags & TSF_HASCOLOURS)
	{
		//FIXME: bytes? channels?
		for (i = 0; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
		{
			Terr_Write_Float(&strm, s->colours[i][0]);
			Terr_Write_Float(&strm, s->colours[i][1]);
			Terr_Write_Float(&strm, s->colours[i][2]);
			Terr_Write_Float(&strm, s->colours[i][3]);
		}
	}

	for (j = 0; j < 4; j++)
		Terr_Write_String(&strm, s->texname[j]);
	for (j = 0; j < 4; j++)
	{
		if (j == 3)
		{
			//only write the channel if it has actual data
			if (!(flags & TSF_HASSHADOW))
				continue;
		}
		else
		{
			//only write the data if there's actually a texture.
			//its not meant to be possible to delete a texture without deleting its data too.
			//
			if (!*s->texname[2-j])
				continue;
		}

		//write the channel
		last = 0;
		lm = lightmap[s->lightmap]->lightmaps;
		lm += (s->lmy * HMLMSTRIDE + s->lmx) * lightmap_bytes;
		for (y = 0; y < SECTTEXSIZE; y++)
		{
			for (x = 0; x < SECTTEXSIZE; x++)
			{
				delta = lm[x*4+j] - last;
				last = lm[x*4+j];
				Terr_Write_Byte(&strm, delta);
			}
			lm += (HMLMSTRIDE)*lightmap_bytes;
		}
	}

	Terr_Write_SInt(&strm, s->numents);
	for (i = 0; i < s->numents; i++)
	{
		unsigned int mf;

		//make sure we don't overflow. we should always be aligned at this point.
		if (strm.pos > strm.maxsize/2)
		{
			VFS_WRITE(f, strm.buffer, strm.pos);
			strm.pos = 0;
		}

		mf = 0;
		if (s->ents[i].scale != 1)
			mf |= TMF_SCALE;
		Terr_Write_SInt(&strm, mf);
		if (s->ents[i].model)
			Terr_Write_String(&strm, s->ents[i].model->name);
		else
			Terr_Write_String(&strm, "*invalid");
		Terr_Write_Float(&strm, s->ents[i].origin[0]+(CHUNKBIAS-sx)*hm->sectionsize);
		Terr_Write_Float(&strm, s->ents[i].origin[1]+(CHUNKBIAS-sy)*hm->sectionsize);
		Terr_Write_Float(&strm, s->ents[i].origin[2]);
		Terr_Write_Float(&strm, s->ents[i].axis[0][0]);
		Terr_Write_Float(&strm, s->ents[i].axis[0][1]);
		Terr_Write_Float(&strm, s->ents[i].axis[0][2]);
		Terr_Write_Float(&strm, s->ents[i].axis[1][0]);
		Terr_Write_Float(&strm, s->ents[i].axis[1][1]);
		Terr_Write_Float(&strm, s->ents[i].axis[1][2]);
		Terr_Write_Float(&strm, s->ents[i].axis[2][0]);
		Terr_Write_Float(&strm, s->ents[i].axis[2][1]);
		Terr_Write_Float(&strm, s->ents[i].axis[2][2]);
		if (mf & TMF_SCALE)
			Terr_Write_Float(&strm, s->ents[i].scale);
	}

	//reset it in case the buffer is getting a little full
	strm.pos = (strm.pos + sizeof(int)-1) & ~(sizeof(int)-1);
	VFS_WRITE(f, strm.buffer, strm.pos);
	strm.pos = 0;
}
#endif
static void *Terr_ReadV2(heightmap_t *hm, hmsection_t *s, void *ptr, int len)
{
#ifndef SERVERONLY
	char modelname[MAX_QPATH];
	qbyte last;
	int y;
	qboolean present;
	qbyte *lm, delta;
#endif
	struct terrstream_s strm = {ptr, len, 0};
	float f;
	int i, j, x;
	unsigned int flags = Terr_Read_SInt(&strm);

	s->flags |= flags & ~TSF_INTERNAL;
	if (flags & TSF_HASHEIGHTS)
	{
		s->minh = s->maxh = s->heights[0] = Terr_Read_Float(&strm);
		for (i = 1; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
		{
			f = Terr_Read_Float(&strm);
			if (s->minh > f)
				s->minh = f;
			if (s->maxh < f)
				s->maxh = f;
			s->heights[i] = f;
		}
	}
	else
	{
		s->minh = s->maxh = f = Terr_Read_Float(&strm);
		for (i = 0; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
			s->heights[i] = f;
	}
	
	for (i = 0; i < sizeof(s->holes); i++)
		s->holes[i] = Terr_Read_Byte(&strm);

	j = Terr_Read_SInt(&strm);
	for (i = 0; i < j; i++)
	{
		struct hmwater_s *w = Z_Malloc(sizeof(*w));
		char shadername[MAX_QPATH];
		int fl = Terr_Read_SInt(&strm);
		w->next = s->water;
		s->water = w;
		w->simple = true;
		w->contentmask = Terr_Read_SInt(&strm);
		if (fl & 1)
			Terr_Read_String(&strm, shadername, sizeof(shadername));
		else
			Q_strncpyz(shadername, hm->watershadername, sizeof(hm->watershadername));
#ifndef SERVERONLY
//		CL_CheckOrEnqueDownloadFile(shadername, NULL, 0);
		w->shader = R_RegisterCustom (shadername, SUF_NONE, Shader_DefaultWaterShader, NULL);
#endif
		if (fl & 2)
		{
			for (x = 0; x < 8; x++)
				w->holes[i] = Terr_Read_Byte(&strm);
			w->simple = false;
		}
		if (fl & 4)
		{
			for (x = 0; x < 9*9; x++)
			{
				w->heights[x] = Terr_Read_Float(&strm);
			}
			w->simple = false;
		}
		else
		{	//all heights the same can be used as a way to compress the data
			w->minheight = w->maxheight = Terr_Read_Float(&strm);
			for (x = 0; x < 9*9; x++)
				w->heights[x] = w->minheight = w->maxheight;
		}
	}

	//dedicated server can stop reading here.

#ifndef SERVERONLY
	if (flags & TSF_HASCOLOURS)
	{
		for (i = 0; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
		{
			s->colours[i][0] = Terr_Read_Float(&strm);
			s->colours[i][1] = Terr_Read_Float(&strm);
			s->colours[i][2] = Terr_Read_Float(&strm);
			s->colours[i][3] = Terr_Read_Float(&strm);
		}
	}
	else
	{
		for (i = 0; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
		{
			s->colours[i][0] = 1;
			s->colours[i][1] = 1;
			s->colours[i][2] = 1;
			s->colours[i][3] = 1;
		}
	}

	for (j = 0; j < 4; j++)
		Terr_Read_String(&strm, s->texname[j], sizeof(s->texname[j]));
	for (j = 0; j < 4; j++)
	{
		if (j == 3)
			present = !!(flags & TSF_HASSHADOW);
		else
			present = !!(*s->texname[2-j]);

		if (present)
		{
			//read the channel
			if (s->lightmap >= 0)
			{
				last = 0;
				lm = lightmap[s->lightmap]->lightmaps;
				lm += (s->lmy * HMLMSTRIDE + s->lmx) * lightmap_bytes;
				for (y = 0; y < SECTTEXSIZE; y++)
				{
					for (x = 0; x < SECTTEXSIZE; x++)
					{
						delta = Terr_Read_Byte(&strm);
						last = (last+delta)&0xff;
						lm[x*4+j] = last;
					}
					lm += (HMLMSTRIDE)*lightmap_bytes;
				}
			}
			else
			{
				strm.pos += SECTTEXSIZE*SECTTEXSIZE;
			}
		}
		else if (s->lightmap >= 0)
		{
			last = ((j==3)?255:0);
			lm = lightmap[s->lightmap]->lightmaps;
			lm += (s->lmy * HMLMSTRIDE + s->lmx) * lightmap_bytes;
			for (y = 0; y < SECTTEXSIZE; y++)
			{
				for (x = 0; x < SECTTEXSIZE; x++)
					lm[x*4+j] = last;
				lm += (HMLMSTRIDE)*lightmap_bytes;
			}
		}
	}

	/*load any static ents*/
	s->numents = Terr_Read_SInt(&strm);
	if (s->maxents)
		BZ_Free(s->ents);
	s->maxents = s->numents;
	if (s->maxents)
		s->ents = BZ_Malloc(sizeof(*s->ents) * s->maxents);
	else
		s->ents = NULL;
	if (!s->ents)
		s->numents = s->maxents = 0;
	for (i = 0; i < s->numents; i++)
	{
		unsigned int mf;
		mf = Terr_Read_SInt(&strm);
		memset(&s->ents[i], 0, sizeof(s->ents[i]));
		s->ents[i].model = Mod_FindName(Terr_Read_String(&strm, modelname, sizeof(modelname)));
		s->ents[i].origin[0] = Terr_Read_Float(&strm);
		s->ents[i].origin[1] = Terr_Read_Float(&strm);
		s->ents[i].origin[2] = Terr_Read_Float(&strm);
		s->ents[i].axis[0][0] = Terr_Read_Float(&strm);
		s->ents[i].axis[0][1] = Terr_Read_Float(&strm);
		s->ents[i].axis[0][2] = Terr_Read_Float(&strm);
		s->ents[i].axis[1][0] = Terr_Read_Float(&strm);
		s->ents[i].axis[1][1] = Terr_Read_Float(&strm);
		s->ents[i].axis[1][2] = Terr_Read_Float(&strm);
		s->ents[i].axis[2][0] = Terr_Read_Float(&strm);
		s->ents[i].axis[2][1] = Terr_Read_Float(&strm);
		s->ents[i].axis[2][2] = Terr_Read_Float(&strm);
		s->ents[i].scale = (mf&TMF_SCALE)?Terr_Read_Float(&strm):1;

		s->ents[i].drawflags = SCALE_ORIGIN_ORIGIN;
		s->ents[i].playerindex = -1;
		s->ents[i].origin[0] += (s->sx-CHUNKBIAS)*hm->sectionsize;
		s->ents[i].origin[1] += (s->sy-CHUNKBIAS)*hm->sectionsize;
		s->ents[i].shaderRGBAf[0] = 1;
		s->ents[i].shaderRGBAf[1] = 1;
		s->ents[i].shaderRGBAf[2] = 1;
		s->ents[i].shaderRGBAf[3] = 1;

		if (!s->ents[i].model)
		{
			s->numents--;
			i--;
		}
	}
#endif
	return ptr;
}

//#include "gl_adt.inc"

static void Terr_GenerateDefault(heightmap_t *hm, hmsection_t *s)
{
#ifndef SERVERONLY
	int i;
#endif

	s->flags |= TSF_FAILEDLOAD;
	memset(s->holes, 0, sizeof(s->holes));

#ifndef SERVERONLY
	Q_strncpyz(s->texname[0], "", sizeof(s->texname[0]));
	Q_strncpyz(s->texname[1], "", sizeof(s->texname[1]));
	Q_strncpyz(s->texname[2], "", sizeof(s->texname[2]));
	Q_strncpyz(s->texname[3], "", sizeof(s->texname[3]));

	if (s->lightmap >= 0)
	{
		int j;
		qbyte *lm;

		lm = lightmap[s->lightmap]->lightmaps;
		lm += (s->lmy * HMLMSTRIDE + s->lmx) * lightmap_bytes;
		for (i = 0; i < SECTTEXSIZE; i++)
		{
			for (j = 0; j < SECTTEXSIZE; j++)
			{
				lm[j*4+0] = 0;
				lm[j*4+0] = 0;
				lm[j*4+0] = 0;
				lm[j*4+3] = 255;
			}
			lm += (HMLMSTRIDE)*lightmap_bytes;
		}
		lightmap[s->lightmap]->modified = true;
		lightmap[s->lightmap]->rectchange.l = 0;
		lightmap[s->lightmap]->rectchange.t = 0;
		lightmap[s->lightmap]->rectchange.w = HMLMSTRIDE;
		lightmap[s->lightmap]->rectchange.h = HMLMSTRIDE;
	}
	for (i = 0; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
	{
		s->colours[i][0] = 1;
		s->colours[i][1] = 1;
		s->colours[i][2] = 1;
		s->colours[i][3] = 1;
	}
	s->mesh.colors4f_array[0] = s->colours;
#endif

#if 0//def DEBUG
	void *f;
	if (lightmap_bytes == 4 && lightmap_bgra && FS_LoadFile(va("maps/%s/splatt.png", hm->path), &f) != (qofs_t)-1)
	{
		//temp
		int vx, vy;
		int x, y;
		extern qbyte *Read32BitImageFile(qbyte *buf, int len, int *width, int *height, qboolean *hasalpha, char *fname);
		int sw, sh;
		qboolean hasalpha;
		unsigned char *splatter = Read32BitImageFile(f, com_filesize, &sw, &sh, &hasalpha, "splattermap");
		if (splatter)
		{
			lm = lightmap[s->lightmap]->lightmaps;
			lm += (s->lmy * HMLMSTRIDE + s->lmx) * lightmap_bytes;

			for (vx = 0; vx < SECTTEXSIZE; vx++)
			{
				x = sw * (((float)sy) + ((float)vx / (SECTTEXSIZE-1))) / hm->numsegsx;
				if (x > sw-1)
					x = sw-1;
				for (vy = 0; vy < SECTTEXSIZE; vy++)
				{
					y = sh * (((float)sx) + ((float)vy / (SECTTEXSIZE-1))) / hm->numsegsy;
					if (y > sh-1)
						y = sh-1;

					lm[2] = splatter[(y + x*sh)*4+0];
					lm[1] = splatter[(y + x*sh)*4+1];
					lm[0] = splatter[(y + x*sh)*4+2];
					lm[3] = splatter[(y + x*sh)*4+3];
					lm += 4;
				}
				lm += (HMLMSTRIDE - SECTTEXSIZE)*lightmap_bytes;
			}
			BZ_Free(splatter);

			lightmap[s->lightmap]->modified = true;
			lightmap[s->lightmap]->rectchange.l = 0;
			lightmap[s->lightmap]->rectchange.t = 0;
			lightmap[s->lightmap]->rectchange.w = HMLMSTRIDE;
			lightmap[s->lightmap]->rectchange.h = HMLMSTRIDE;
		}
		FS_FreeFile(f);
	}

	if (lightmap_bytes == 4 && lightmap_bgra && !qofs_Error(FS_LoadFile(va("maps/%s/heightmap.png", hm->path), &f)))
	{
		//temp
		int vx, vy;
		int x, y;
		extern qbyte *Read32BitImageFile(qbyte *buf, int len, int *width, int *height, qboolean *hasalpha, char *fname);
		int sw, sh;
		float *h;
		qboolean hasalpha;
		unsigned char *hmimage = Read32BitImageFile(f, com_filesize, &sw, &sh, &hasalpha, "heightmap");
		if (hmimage)
		{
			h = s->heights;

			for (vx = 0; vx < SECTHEIGHTSIZE; vx++)
			{
				x = sw * (((float)sy) + ((float)vx / (SECTHEIGHTSIZE-1))) / hm->numsegsx;
				if (x > sw-1)
					x = sw-1;
				for (vy = 0; vy < SECTHEIGHTSIZE; vy++)
				{
					y = sh * (((float)sx) + ((float)vy / (SECTHEIGHTSIZE-1))) / hm->numsegsy;
					if (y > sh-1)
						y = sh-1;

					*h = 0;
					*h += hmimage[(y + x*sh)*4+0];
					*h += hmimage[(y + x*sh)*4+1]<<8;
					*h += hmimage[(y + x*sh)*4+2]<<16;
					*h *= 4.0f/(1<<16);
					h++;
				}
			}
			BZ_Free(hmimage);
		}
		FS_FreeFile(f);
	}
#endif
}
static hmsection_t *Terr_ReadSection(heightmap_t *hm, int ver, int sx, int sy, void *filebase, unsigned int filelen)
{
	void *ptr = filebase;

	hmsection_t *s;
	hmcluster_t *cluster;
	int clusternum = (sx/MAXSECTIONS) + (sy/MAXSECTIONS)*MAXCLUSTERS;
	cluster = hm->cluster[clusternum];
	if (!cluster)
		cluster = hm->cluster[clusternum] = Z_Malloc(sizeof(*cluster));
	s = cluster->section[(sx%MAXSECTIONS) + (sy%MAXSECTIONS)*MAXSECTIONS];

	if (!s)
	{
		s = Terr_GenerateSection(hm, sx, sy);
		if (!s)
			return NULL;
	}

#ifndef SERVERONLY
	Terr_InitLightmap(s, false);
#endif

	s->flags &= ~TSF_FAILEDLOAD;
	if (ptr && ver == 1)
		Terr_ReadV1(hm, s, ptr, filelen);
	else if (ptr && ver == 2)
		Terr_ReadV2(hm, s, ptr, filelen);
	else
	{
		s->flags |= TSF_FAILEDLOAD;
//		s->flags |= TSF_RELIGHT;
		Terr_GenerateDefault(hm, s);
	}

	Terr_LoadSectionTextures(s);

	return s;
}

#ifndef SERVERONLY
qboolean Terr_DownloadedSection(char *fname)
{
	qofs_t len;
	dsection_t *fileptr;
	int x, y;
	heightmap_t *hm;
	int ver = 0;

	if (!cl.worldmodel)
		return false;

	hm = cl.worldmodel->terrain;

	if (Terr_IsSectionFName(hm, fname, &x, &y))
	{
		fileptr = NULL;
		len = FS_LoadFile(fname, (void**)&fileptr);

		if (!qofs_Error(len) && len >= sizeof(*fileptr) && fileptr->magic == SECTION_MAGIC)
			Terr_ReadSection(hm, ver, x, y, fileptr+1, len - sizeof(*fileptr));
		else
			Terr_ReadSection(hm, ver, x, y, NULL, 0);

		if (fileptr)
			FS_FreeFile(fileptr);
		return true;
	}

	return false;
}
#endif

static void Terr_LoadSection(heightmap_t *hm, hmsection_t *s, int sx, int sy, unsigned int flags)
{
	void *diskimage;
	qofs_t len;
#ifndef SERVERONLY
	//when using networked terrain, the client will never load a section from disk, but will only load it from the server
	//one section at a time.
	if (mod_terrain_networked.ival && !sv.state)
	{
		if (flags & TGS_NODOWNLOAD)
			return;
		//try to download it now...
		if (!cl.downloadlist)
			CL_CheckOrEnqueDownloadFile(Terr_DiskSectionName(hm, sx, sy), Terr_TempDiskSectionName(hm, sx, sy), DLLF_OVERWRITE|DLLF_TEMPORARY);
		return;
	}
#endif

#if SECTIONSPERBLOCK > 1
	len = FS_LoadFile(Terr_DiskBlockName(hm, sx, sy), (void**)&diskimage);
	if (!qofs_Error(len))
	{
		int offset;
		int x, y;
		int ver;
		dblock_t *block = diskimage;
		if (block->magic != SECTION_MAGIC || !(block->ver & 0x80000000))
		{
			//give it a dummy so we don't constantly hit the disk
			Terr_ReadSection(hm, 0, sx, sy, NULL, 0);
		}
		else
		{
			sx&=~(SECTIONSPERBLOCK-1);
			sy&=~(SECTIONSPERBLOCK-1);

			ver = block->ver & ~0x80000000;
			for (y = 0; y < SECTIONSPERBLOCK; y++)
				for (x = 0; x < SECTIONSPERBLOCK; x++)
				{
					//noload avoids recursion.
					s = Terr_GetSection(hm, sx+x, sy+y, TGS_NOLOAD|TGS_NODOWNLOAD|TGS_IGNOREFAILED);
					if (!s || s->flags & TSF_FAILEDLOAD 
#ifndef SERVERONLY
						|| s->lightmap < 0
#endif
						)
					{
						offset = block->offset[x + y*SECTIONSPERBLOCK];
						if (!offset)
							Terr_ReadSection(hm, ver, sx+x, sy+y, NULL, 0);	//no data in the file for this section
						else
							Terr_ReadSection(hm, ver, sx+x, sy+y, (char*)diskimage + offset, len - offset);
					}
				}
		}
		FS_FreeFile(diskimage);
		return;
	}
#endif

	//legacy one-section-per-file format.
	len = FS_LoadFile(Terr_DiskSectionName(hm, sx, sy), (void**)&diskimage);
	if (!qofs_Error(len))
	{
		dsection_t *h = diskimage;
		if (len >= sizeof(*h) && h->magic == SECTION_MAGIC)
		{
			Terr_ReadSection(hm, h->ver, sx, sy, h+1, len-sizeof(*h));
			FS_FreeFile(diskimage);
			return;
		}
		if (diskimage)
			FS_FreeFile(diskimage);
	}

#ifdef ADT
	if (Terr_ImportADT(hm, sx, sy, flags))
		return;
#endif

	//generate a dummy one
	Terr_ReadSection(hm, 0, sx, sy, NULL, 0);

	//download it if it couldn't be loaded.
#ifndef SERVERONLY
	if (!cl.downloadlist && !(flags & TGS_NODOWNLOAD))
		CL_CheckOrEnqueDownloadFile(Terr_DiskSectionName(hm, sx, sy), NULL, 0);
#endif
}

#ifndef SERVERONLY
static void Terr_SaveV1(heightmap_t *hm, hmsection_t *s, vfsfile_t *f, int sx, int sy)
{
	int i;
	dsmesh_t dm;
	qbyte *lm;
	dsection_v1_t ds;
	vec4_t dcolours[SECTHEIGHTSIZE*SECTHEIGHTSIZE];
	int nothing = 0;
	struct hmwater_s *w = s->water;

	memset(&ds, 0, sizeof(ds));
	memset(&dm, 0, sizeof(dm));

	//mask off the flags which are only valid in memory
	ds.flags = s->flags & ~(TSF_INTERNAL|TSF_HASWATER_V0);

	//kill the haswater flag if its entirely above any possible water anyway.
	if (w)
		ds.flags |= TSF_HASWATER_V0;
	ds.flags &= ~TSF_HASCOLOURS;	//recalculated

	Q_strncpyz(ds.texname[0], s->texname[0], sizeof(ds.texname[0]));
	Q_strncpyz(ds.texname[1], s->texname[1], sizeof(ds.texname[1]));
	Q_strncpyz(ds.texname[2], s->texname[2], sizeof(ds.texname[2]));
	Q_strncpyz(ds.texname[3], s->texname[3], sizeof(ds.texname[3]));

	for (i = 0; i < 8*8; i++)
	{
		int x = (i & 7);
		int y = (i>>3);
		int b = (1u<<(x>>1)) << ((y>>1)<<2);
		if (s->holes[y] & (1u<<x))
			ds.holes |= b;
	}

	//make sure the user can see the holes they just saved.
	memset(s->holes, 0, sizeof(s->holes));
	for (i = 0; i < 8*8; i++)
	{
		int x = (i & 7);
		int y = (i>>3);
		int b = (1u<<(x>>1)) << ((y>>1)<<2);
		if (ds.holes & b)
			s->holes[y] |= 1u<<x;
	}
	s->flags |= TSF_DIRTY;

	lm = lightmap[s->lightmap]->lightmaps;
	lm += (s->lmy * HMLMSTRIDE + s->lmx) * lightmap_bytes;
	for (i = 0; i < SECTTEXSIZE; i++)
	{
		memcpy(ds.texmap + i, lm, sizeof(ds.texmap[0]));
		lm += (HMLMSTRIDE)*lightmap_bytes;
	}

	for (i = 0; i < SECTHEIGHTSIZE*SECTHEIGHTSIZE; i++)
	{
		ds.heights[i] = LittleFloat(s->heights[i]);

		if (s->colours[i][0] != 1 || s->colours[i][1] != 1 || s->colours[i][2] != 1 || s->colours[i][3] != 1)
		{
			ds.flags |= TSF_HASCOLOURS;
			dcolours[i][0] = LittleFloat(s->colours[i][0]);
			dcolours[i][1] = LittleFloat(s->colours[i][1]);
			dcolours[i][2] = LittleFloat(s->colours[i][2]);
			dcolours[i][3] = LittleFloat(s->colours[i][3]);
		}
		else
		{
			dcolours[i][0] = dcolours[i][1] = dcolours[i][2] = dcolours[i][3] = LittleFloat(1);
		}
	}
	ds.waterheight = w?w->heights[4*8+4]:s->minh;
	ds.minh = s->minh;
	ds.maxh = s->maxh;
	ds.ents_num = s->numents;

	VFS_WRITE(f, &ds, sizeof(ds));
	if (ds.flags & TSF_HASCOLOURS)
		VFS_WRITE(f, dcolours, sizeof(dcolours));
	for (i = 0; i < s->numents; i++)
	{
		int pad;
		dm.scale = s->ents[i].scale;
		VectorCopy(s->ents[i].axis[0], dm.axisorg[0]);
		VectorCopy(s->ents[i].axis[1], dm.axisorg[1]);
		VectorCopy(s->ents[i].axis[2], dm.axisorg[2]);
		VectorCopy(s->ents[i].origin, dm.axisorg[3]);
		dm.axisorg[3][0] += (CHUNKBIAS-sx)*hm->sectionsize;
		dm.axisorg[3][1] += (CHUNKBIAS-sy)*hm->sectionsize;
		dm.size = sizeof(dm) + strlen(s->ents[i].model->name) + 1;
		if (dm.size & 3)
			pad = 4 - (dm.size&3);
		else
			pad = 0;
		dm.size += pad;
		VFS_WRITE(f, &dm, sizeof(dm));
		VFS_WRITE(f, s->ents[i].model->name, strlen(s->ents[i].model->name)+1);
		if (pad)
			VFS_WRITE(f, &nothing, pad);
	}
}

static void Terr_Save(heightmap_t *hm, hmsection_t *s, vfsfile_t *f, int sx, int sy, int ver)
{
	if (ver == 1)
		Terr_SaveV1(hm, s, f, sx, sy);
	else if (ver == 2)
		Terr_SaveV2(hm, s, f, sx, sy);
}
#endif

//doesn't clear edited/dirty flags or anything
static qboolean Terr_SaveSection(heightmap_t *hm, hmsection_t *s, int sx, int sy, qboolean blocksave)
{
#ifdef SERVERONLY
	return true;
#else
	vfsfile_t *f;
	char *fname;
	int x, y;
	int writever = mod_terrain_savever.ival;
	if (!writever)
		writever = SECTION_VER_DEFAULT;
	//if its invalid or doesn't contain all the data...
	if (!s || s->lightmap < 0)
		return true;

#if SECTIONSPERBLOCK > 1
	if (blocksave)
	{
		dblock_t dbh;
		sx = sx & ~(SECTIONSPERBLOCK-1);
		sy = sy & ~(SECTIONSPERBLOCK-1);

		//make sure its loaded before we replace the file
		for (y = 0; y < SECTIONSPERBLOCK; y++)
		{
			for (x = 0; x < SECTIONSPERBLOCK; x++)
			{
				s = Terr_GetSection(hm, sx+x, sy+y, TGS_LOAD);
				if (s)
					s->flags |= TSF_EDITED;	//stop them from getting reused for something else.
			}
		}

		fname = Terr_DiskBlockName(hm, sx, sy);
		FS_CreatePath(fname, FS_GAMEONLY);
		f = FS_OpenVFS(fname, "wb", FS_GAMEONLY);
		if (!f)
		{
			Con_Printf("Failed to open %s\n", fname);
			return false;
		}

		memset(&dbh, 0, sizeof(dbh));
		dbh.magic = LittleLong(SECTION_MAGIC);
		dbh.ver = LittleLong(writever | 0x80000000);
		VFS_WRITE(f, &dbh, sizeof(dbh));
		for (y = 0; y < SECTIONSPERBLOCK; y++)
		{
			for (x = 0; x < SECTIONSPERBLOCK; x++)
			{
				s = Terr_GetSection(hm, sx+x, sy+y, TGS_LOAD);
				if (s)
				{
					dbh.offset[y*SECTIONSPERBLOCK + x] = VFS_TELL(f);
					Terr_Save(hm, s, f, sx+x, sy+y, writever);
					s->flags &= ~TSF_EDITED;
				}
				else
					dbh.offset[y*SECTIONSPERBLOCK + x] = 0;
			}
		}

		VFS_SEEK(f, 0);
		VFS_WRITE(f, &dbh, sizeof(dbh));
		VFS_CLOSE(f);
	}
	else
#endif
	{
		dsection_t dsh;
		fname = Terr_DiskSectionName(hm, sx, sy);

		FS_CreatePath(fname, FS_GAMEONLY);
		f = FS_OpenVFS(fname, "wb", FS_GAMEONLY);
		if (!f)
		{
			Con_Printf("Failed to open %s\n", fname);
			return false;
		}

		memset(&dsh, 0, sizeof(dsh));
		dsh.magic = SECTION_MAGIC;
		dsh.ver = writever;
		VFS_WRITE(f, &dsh, sizeof(dsh));
		Terr_Save(hm, s, f, sx, sy, writever);
		VFS_CLOSE(f);
	}
	return true;
#endif
}

/*convienience function*/
static hmsection_t *Terr_GetSection(heightmap_t *hm, int x, int y, unsigned int flags)
{
	hmcluster_t *cluster;
	hmsection_t *section;
	int cx = x / MAXSECTIONS;
	int cy = y / MAXSECTIONS;
	int sx = x & (MAXSECTIONS-1);
	int sy = y & (MAXSECTIONS-1);
	cluster = hm->cluster[cx + cy*MAXCLUSTERS];
	if (!cluster)
	{
		if (flags & (TGS_LOAD|TGS_FORCELOAD|TGS_LAZYLOAD))
		{
			cluster = Z_Malloc(sizeof(*cluster));
			if (!cluster)
				return NULL;
			hm->cluster[cx + cy*MAXCLUSTERS] = cluster;
		}
		else
			return NULL;
	}
	section = cluster->section[sx + sy*MAXSECTIONS];
	if (!section)
	{
		if (flags & (TGS_LOAD|TGS_FORCELOAD|TGS_LAZYLOAD))
		{
			if ((flags & TGS_LAZYLOAD) && hm->beinglazy)
				return NULL;
			hm->beinglazy = true;
//			while (hm->activesections > TERRAINACTIVESECTIONS)
//				Terr_Collect(hm);
			Terr_LoadSection(hm, section, x, y, flags);
			section = cluster->section[sx + sy*MAXSECTIONS];
		}
	}
#ifndef SERVERONLY
	//when using networked terrain, the client will never load a section from disk, but only loading it from the server
	if (!(flags & TGS_NODOWNLOAD))
	if (section && (section->flags & TSF_NOTIFY) && mod_terrain_networked.ival && !sv.state)
	{
		//try to download it now...
		if (!cl.downloadlist)
		{
			CL_CheckOrEnqueDownloadFile(Terr_DiskSectionName(hm, x, y), Terr_TempDiskSectionName(hm, x, y), DLLF_OVERWRITE|DLLF_TEMPORARY);

			section->flags &= ~TSF_NOTIFY;
		}
	}
#endif

	if (section && (section->flags & TSF_FAILEDLOAD))
	{
		if (flags & TGS_FORCELOAD)
			section->flags &= ~TSF_FAILEDLOAD;
		else
			section = NULL;
	}

	return section;
}

/*save all currently loaded sections*/
int Heightmap_Save(heightmap_t *hm)
{
	hmsection_t *s, *os;
	int x, y, sx, sy;
	int sectionssaved = 0;
	for (x = hm->firstsegx; x < hm->maxsegx; x++)
	{
		for (y = hm->firstsegy; y < hm->maxsegy; y++)
		{
			s = Terr_GetSection(hm, x, y, TGS_NOLOAD);
			if (!s)
				continue;
			if (s->flags & TSF_EDITED)
			{
				//make sure all the parts are loaded before trying to write them, so we don't try reading partial files, which would be bad, mmkay?
				for (sy = y&~(SECTIONSPERBLOCK-1); sy < y+SECTIONSPERBLOCK && sy < hm->maxsegy; sy++)
				{
					for (sx = x&~(SECTIONSPERBLOCK-1); sx < x+SECTIONSPERBLOCK && sx < hm->maxsegx; sx++)
					{
						os = Terr_GetSection(hm, sx, sy, TGS_LOAD|TGS_NODOWNLOAD|TGS_NORENDER);
						if (os)
							os->flags |= TSF_EDITED;
					}
				}


				if (Terr_SaveSection(hm, s, x, y, true))
				{
					s->flags &= ~TSF_EDITED;
					sectionssaved++;
				}
			}
		}
	}

	return sectionssaved;
}

#ifndef CLIENTONLY
//on servers, we can get requests to download current map sections. if so, give them it.
qboolean Terrain_LocateSection(char *name, flocation_t *loc)
{
	heightmap_t *hm;
	hmsection_t *s;
	int x, y;

	//reject if its not in maps
	if (strncmp(name, "maps/", 5))
		return false;

	if (!sv.world.worldmodel)
		return false;
	hm = sv.world.worldmodel->terrain;
	if (!Terr_IsSectionFName(hm, name, &x, &y))
		return false;

	//verify that its valid
	if (strcmp(name, Terr_DiskSectionName(hm, x, y)))
		return false;

	s = Terr_GetSection(hm, x, y, TGS_NOLOAD);
	if (!s || !(s->flags & TSF_EDITED))
		return false;	//its not been edited, might as well just use the regular file

	if (!Terr_SaveSection(hm, s, x, y, false))
		return false;

	return FS_FLocateFile(name, FSLFRT_IFFOUND, loc);
}
#endif

void Terr_DestroySection(heightmap_t *hm, hmsection_t *s, qboolean lightmapreusable)
{
	RemoveLink(&s->recycle);
#ifndef SERVERONLY
	if (s->lightmap >= 0)
	{
		struct lmsect_s *lms;

		if (lightmapreusable)
		{
			lms = BZ_Malloc(sizeof(*lms));
			lms->lm = s->lightmap;
			lms->x = s->lmx;
			lms->y = s->lmy;
			lms->next = hm->unusedlmsects;
			hm->unusedlmsects = lms;
			hm->numunusedlmsects++;
		}
		hm->numusedlmsects--;
	}

	if (hm->relight == s)
		hm->relight = NULL;

#ifdef GLQUAKE
	if (qrenderer == QR_OPENGL && qglDeleteBuffersARB)
	{
		qglDeleteBuffersARB(1, &s->vbo.coord.gl.vbo);
		qglDeleteBuffersARB(1, &s->vbo.indicies.gl.vbo);
	}
#endif

	Z_Free(s->ents);
	Z_Free(s->mesh.xyz_array);
	Z_Free(s->mesh.indexes);
#endif

	Z_Free(s);

	hm->activesections--;
}

#ifndef SERVERONLY
//dedicated servers do not support editing. no lightmap info causes problems.
static void Terr_DoEditNotify(heightmap_t *hm)
{
	int i;
	char *cmd;
	hmsection_t *s;
	link_t *ln = &hm->recycle;

	if (!sv.state)
		return;

	for (i = 0; i < sv.allocated_client_slots; i++)
	{
		if (svs.clients[i].state >= cs_connected && svs.clients[i].netchan.remote_address.type != NA_LOOPBACK)
		{
			if (svs.clients[i].backbuf.cursize)
				return;
		}
	}

	for (ln = &hm->recycle; ln->next != &hm->recycle; ln = &s->recycle)
	{
		s = (hmsection_t*)ln->next;
		if (s->flags & TSF_NOTIFY)
		{
			s->flags &= ~TSF_NOTIFY;
			cmd = va("mod_terrain_reload %s %i %i\n", hm->path, s->sx - CHUNKBIAS, s->sy - CHUNKBIAS);
			for (i = 0; i < sv.allocated_client_slots; i++)
			{
				if (svs.clients[i].state >= cs_connected && svs.clients[i].netchan.remote_address.type != NA_LOOPBACK)
				{
					SV_StuffcmdToClient(&svs.clients[i], cmd);
				}
			}
			return;
		}
	}
}

//garbage collect the oldest section, to make space for another
static qboolean Terr_Collect(heightmap_t *hm)
{
	hmcluster_t *c;
	hmsection_t *s;
	int cx, cy;
	int sx, sy;

	link_t *ln = &hm->recycle;
	for (ln = &hm->recycle; ln->next != &hm->recycle; )
	{
		s = (hmsection_t*)ln->next;
		if (s->flags & TSF_EDITED)
			ln = &s->recycle;
		else
		{
			cx = s->sx/MAXSECTIONS;
			cy = s->sy/MAXSECTIONS;
			c = hm->cluster[cx + cy*MAXCLUSTERS];
			sx = s->sx & (MAXSECTIONS-1);
			sy = s->sy & (MAXSECTIONS-1);
			if (c->section[sx+sy*MAXSECTIONS] != s)
				Sys_Error("invalid section collection");
			c->section[sx+sy*MAXSECTIONS] = NULL;

#if 0
			if (hm->relight == s)
				hm->relight = NULL;
			RemoveLink(&s->recycle);
			InsertLinkAfter(&s->recycle, &hm->collected);
			hm->activesections--;
#else
			Terr_DestroySection(hm, s, true);
#endif
			return true;
		}
	}
	return false;
}
#endif

/*purge all sections, but not root
lightmaps only are purged whenever the client rudely kills lightmaps
we'll reload those when its next seen.
(lightmaps will already have been destroyed, so no poking them)
*/
void Terr_PurgeTerrainModel(model_t *mod, qboolean lightmapsonly, qboolean lightmapreusable)
{
	heightmap_t *hm = mod->terrain;
	hmcluster_t *c;
	hmsection_t *s;
	int cx, cy;
	int sx, sy;

//	Con_Printf("PrePurge: %i lm chunks used, %i unused\n", hm->numusedlmsects, hm->numunusedlmsects);

	for (cy = 0; cy < MAXCLUSTERS; cy++)
	for (cx = 0; cx < MAXCLUSTERS; cx++)
	{
		int numremaining = 0;
		c = hm->cluster[cx + cy*MAXCLUSTERS];
		if (!c)
			continue;

		for (sy = 0; sy < MAXSECTIONS; sy++)
		for (sx = 0; sx < MAXSECTIONS; sx++)
		{
			s = c->section[sx + sy*MAXSECTIONS];
			if (!s)
			{
			}
			else if (lightmapsonly)
			{
				numremaining++;
#ifndef SERVERONLY
				s->lightmap = -1;
#endif
			}
			else
			{
				c->section[sx+sy*MAXSECTIONS] = NULL;

				Terr_DestroySection(hm, s, lightmapreusable);
			}
		}
		if (!numremaining)
		{
			hm->cluster[cx + cy*MAXSECTIONS] = NULL;
			BZ_Free(c);
		}
	}
#ifndef SERVERONLY
	if (!lightmapreusable)
	{
		while (hm->unusedlmsects)
		{
			struct lmsect_s *lms;
			lms = hm->unusedlmsects;
			hm->unusedlmsects = lms->next;
			BZ_Free(lms);

			hm->numunusedlmsects--;
		}
	}
#endif

//	Con_Printf("PostPurge: %i lm chunks used, %i unused\n", hm->numusedlmsects, hm->numunusedlmsects);
}
void Terr_FreeModel(model_t *mod)
{
	heightmap_t *hm = mod->terrain;
	if (hm)
	{
		Terr_PurgeTerrainModel(mod, false, false);
		Z_Free(hm);
		mod->terrain = NULL;
	}
}
#ifndef SERVERONLY
void Terr_DrawTerrainWater(heightmap_t *hm, float *mins, float *maxs, struct hmwater_s *w)
{
	scenetris_t *t;
	int flags = BEF_NOSHADOWS;
	int firstv;
	int y, x;
	
	//need to filter by height too, or reflections won't work properly.
	if (cl_numstris && cl_stris[cl_numstris-1].shader == w->shader && cl_stris[cl_numstris-1].flags == flags && cl_strisvertv[cl_stris[cl_numstris-1].firstvert][2] == w->maxheight)
	{
		t = &cl_stris[cl_numstris-1];
	}
	else
	{
		if (cl_numstris == cl_maxstris)
		{
			cl_maxstris+=8;
			cl_stris = BZ_Realloc(cl_stris, sizeof(*cl_stris)*cl_maxstris);
		}
		t = &cl_stris[cl_numstris++];
		t->shader = w->shader;
		t->flags = flags;
		t->firstidx = cl_numstrisidx;
		t->firstvert = cl_numstrisvert;
		t->numvert = 0;
		t->numidx = 0;
	}

	if (!w->simple)
	{
		float step = (maxs[0] - mins[0]) / 8;
		if (cl_numstrisidx+9*9*6 > cl_maxstrisidx)
		{
			cl_maxstrisidx=cl_numstrisidx+12 + 9*9*6*4;
			cl_strisidx = BZ_Realloc(cl_strisidx, sizeof(*cl_strisidx)*cl_maxstrisidx);
		}
		if (cl_numstrisvert+9*9 > cl_maxstrisvert)
		{
			cl_maxstrisvert+=9*9+64;
			cl_strisvertv = BZ_Realloc(cl_strisvertv, sizeof(*cl_strisvertv)*cl_maxstrisvert);
			cl_strisvertt = BZ_Realloc(cl_strisvertt, sizeof(*cl_strisvertt)*cl_maxstrisvert);
			cl_strisvertc = BZ_Realloc(cl_strisvertc, sizeof(*cl_strisvertc)*cl_maxstrisvert);
		}

		firstv = t->numvert;
		for (y = 0; y < 9; y++)
		{
			for (x = 0; x < 9; x++)
			{
				cl_strisvertv[cl_numstrisvert][0] = mins[0] + step*x;
				cl_strisvertv[cl_numstrisvert][1] = mins[1] + step*y;
				cl_strisvertv[cl_numstrisvert][2] = w->heights[x + y*9];
				cl_strisvertt[cl_numstrisvert][0] = cl_strisvertv[cl_numstrisvert][0]/64;
				cl_strisvertt[cl_numstrisvert][1] = cl_strisvertv[cl_numstrisvert][1]/64;
				Vector4Set(cl_strisvertc[cl_numstrisvert], 1,1,1,1)
				cl_numstrisvert++;
			}
		}
		for (y = 0; y < 8; y++)
		{
			for (x = 0; x < 8; x++)
			{
				if (w->holes[y] & (1u<<x))
					continue;
				cl_strisidx[cl_numstrisidx++] = firstv+(x+0)+(y+0)*9;
				cl_strisidx[cl_numstrisidx++] = firstv+(x+0)+(y+1)*9;
				cl_strisidx[cl_numstrisidx++] = firstv+(x+1)+(y+0)*9;

				cl_strisidx[cl_numstrisidx++] = firstv+(x+1)+(y+0)*9;
				cl_strisidx[cl_numstrisidx++] = firstv+(x+0)+(y+1)*9;
				cl_strisidx[cl_numstrisidx++] = firstv+(x+1)+(y+1)*9;
			}
		}
		t->numidx = cl_numstrisidx - t->firstidx;
		t->numvert = cl_numstrisvert - t->firstvert;
	}
	else
	{
		if (cl_numstrisidx+12 > cl_maxstrisidx)
		{
			cl_maxstrisidx=cl_numstrisidx+12 + 64;
			cl_strisidx = BZ_Realloc(cl_strisidx, sizeof(*cl_strisidx)*cl_maxstrisidx);
		}
		if (cl_numstrisvert+4 > cl_maxstrisvert)
		{
			cl_maxstrisvert+=64;
			cl_strisvertv = BZ_Realloc(cl_strisvertv, sizeof(*cl_strisvertv)*cl_maxstrisvert);
			cl_strisvertt = BZ_Realloc(cl_strisvertt, sizeof(*cl_strisvertt)*cl_maxstrisvert);
			cl_strisvertc = BZ_Realloc(cl_strisvertc, sizeof(*cl_strisvertc)*cl_maxstrisvert);
		}

		{
			VectorSet(cl_strisvertv[cl_numstrisvert], mins[0], mins[1], w->maxheight);
			Vector4Set(cl_strisvertc[cl_numstrisvert], 1,1,1,1)
			Vector2Set(cl_strisvertt[cl_numstrisvert], mins[0]/64, mins[1]/64);
			cl_numstrisvert++;

			VectorSet(cl_strisvertv[cl_numstrisvert], mins[0], maxs[1], w->maxheight);
			Vector4Set(cl_strisvertc[cl_numstrisvert], 1,1,1,1)
			Vector2Set(cl_strisvertt[cl_numstrisvert], mins[0]/64, maxs[1]/64);
			cl_numstrisvert++;

			VectorSet(cl_strisvertv[cl_numstrisvert], maxs[0], maxs[1], w->maxheight);
			Vector4Set(cl_strisvertc[cl_numstrisvert], 1,1,1,1)
			Vector2Set(cl_strisvertt[cl_numstrisvert], maxs[0]/64, maxs[1]/64);
			cl_numstrisvert++;

			VectorSet(cl_strisvertv[cl_numstrisvert], maxs[0], mins[1], w->maxheight);
			Vector4Set(cl_strisvertc[cl_numstrisvert], 1,1,1,1)
			Vector2Set(cl_strisvertt[cl_numstrisvert], maxs[0]/64, mins[1]/64);
			cl_numstrisvert++;
		}


		firstv = t->numvert;

		/*build the triangles*/
		cl_strisidx[cl_numstrisidx++] = firstv + 0;
		cl_strisidx[cl_numstrisidx++] = firstv + 1;
		cl_strisidx[cl_numstrisidx++] = firstv + 2;

		cl_strisidx[cl_numstrisidx++] = firstv + 0;
		cl_strisidx[cl_numstrisidx++] = firstv + 2;
		cl_strisidx[cl_numstrisidx++] = firstv + 3;

		cl_strisidx[cl_numstrisidx++] = firstv + 3;
		cl_strisidx[cl_numstrisidx++] = firstv + 2;
		cl_strisidx[cl_numstrisidx++] = firstv + 1;

		cl_strisidx[cl_numstrisidx++] = firstv + 3;
		cl_strisidx[cl_numstrisidx++] = firstv + 1;
		cl_strisidx[cl_numstrisidx++] = firstv + 0;


		t->numidx = cl_numstrisidx - t->firstidx;
		t->numvert = cl_numstrisvert - t->firstvert;
	}
}

static void Terr_RebuildMesh(model_t *model, hmsection_t *s, int x, int y)
{
	int vx, vy;
	int v;
	mesh_t *mesh = &s->mesh;
	heightmap_t *hm = s->hmmod;
	
	Terr_InitLightmap(s, false);

	s->minh = 9999999999999999.f;
	s->maxh = -9999999999999999.f;

	switch(hm->mode)
	{
	case HMM_BLOCKS:
		//tiles, like dungeon keeper
		if (mesh->xyz_array)
			BZ_Free(mesh->xyz_array);
		{
			mesh->xyz_array = BZ_Malloc((sizeof(vecV_t)+sizeof(vec2_t)+sizeof(vec2_t)) * (SECTHEIGHTSIZE-1)*(SECTHEIGHTSIZE-1)*4*3);
			mesh->st_array = (void*) (mesh->xyz_array + (SECTHEIGHTSIZE-1)*(SECTHEIGHTSIZE-1)*4*3);
			mesh->lmst_array[0] = (void*) (mesh->st_array + (SECTHEIGHTSIZE-1)*(SECTHEIGHTSIZE-1)*4*3);
		}
		mesh->numvertexes = 0;

		if (mesh->indexes)
			BZ_Free(mesh->indexes);
		mesh->indexes = BZ_Malloc(sizeof(index_t) * SECTHEIGHTSIZE*SECTHEIGHTSIZE*6*3);
		mesh->numindexes = 0;
		mesh->colors4f_array[0] = NULL;

		for (vy = 0; vy < SECTHEIGHTSIZE-1; vy++)
		{
			for (vx = 0; vx < SECTHEIGHTSIZE-1; vx++)
			{
				float st[2], inst[2];
#if SECTHEIGHTSIZE == 17
				int holebit;
				int holerow;

				//skip generation of the mesh above holes
				holerow = ((vy<<3)/(SECTHEIGHTSIZE-1));
				holebit = 1u<<((vx<<3)/(SECTHEIGHTSIZE-1));
				if (s->holes[holerow] & holebit)
					continue;
#endif

				//top face
				v = mesh->numvertexes;
				mesh->numvertexes += 4;
				mesh->xyz_array[v+0][0] = (x-CHUNKBIAS + (vx+0)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+0][1] = (y-CHUNKBIAS + (vy+0)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+0][2] = s->heights[vx + vy*SECTHEIGHTSIZE];

				mesh->xyz_array[v+1][0] = (x-CHUNKBIAS + (vx+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+1][1] = (y-CHUNKBIAS + (vy+0)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+1][2] = s->heights[vx + vy*SECTHEIGHTSIZE];

				mesh->xyz_array[v+2][0] = (x-CHUNKBIAS + (vx+0)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+2][1] = (y-CHUNKBIAS + (vy+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+2][2] = s->heights[vx + vy*SECTHEIGHTSIZE];

				mesh->xyz_array[v+3][0] = (x-CHUNKBIAS + (vx+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+3][1] = (y-CHUNKBIAS + (vy+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+3][2] = s->heights[vx + vy*SECTHEIGHTSIZE];

				if (s->maxh < mesh->xyz_array[v][2])
					s->maxh = mesh->xyz_array[v][2];
				if (s->minh > mesh->xyz_array[v][2])
					s->minh = mesh->xyz_array[v][2];

				st[0] = 1.0f/hm->tilecount[0] * vx;
				st[1] = 1.0f/hm->tilecount[1] * vy;
				inst[0] = 0.5f/(hm->tilecount[0]*hm->tilepixcount[0]);
				inst[1] = 0.5f/(hm->tilecount[1]*hm->tilepixcount[1]);
				mesh->st_array[v+0][0] = st[0]+inst[0];
				mesh->st_array[v+0][1] = st[1]+inst[1];
				mesh->st_array[v+1][0] = st[0]-inst[0]+1.0f/hm->tilecount[0];
				mesh->st_array[v+1][1] = st[1]+inst[1];
				mesh->st_array[v+2][0] = st[0]+inst[0];
				mesh->st_array[v+2][1] = st[1]-inst[1]+1.0f/hm->tilecount[1];
				mesh->st_array[v+3][0] = st[0]-inst[0]+1.0f/hm->tilecount[0];
				mesh->st_array[v+3][1] = st[1]-inst[1]+1.0f/hm->tilecount[1];

				//calc the position in the range -0.5 to 0.5
				mesh->lmst_array[0][v][0] = (((float)vx / (SECTHEIGHTSIZE-1))-0.5);
				mesh->lmst_array[0][v][1] = (((float)vy / (SECTHEIGHTSIZE-1))-0.5);
				//scale down to a half-texel
				mesh->lmst_array[0][v][0] *= (SECTTEXSIZE-1.0f)/HMLMSTRIDE;
				mesh->lmst_array[0][v][1] *= (SECTTEXSIZE-1.0f)/HMLMSTRIDE;
				//bias it
				mesh->lmst_array[0][v][0] += ((float)SECTTEXSIZE/(HMLMSTRIDE*2)) + ((float)(s->lmx) / HMLMSTRIDE);
				mesh->lmst_array[0][v][1] += ((float)SECTTEXSIZE/(HMLMSTRIDE*2)) + ((float)(s->lmy) / HMLMSTRIDE);

				mesh->indexes[mesh->numindexes++] = v+0;
				mesh->indexes[mesh->numindexes++] = v+2;
				mesh->indexes[mesh->numindexes++] = v+1;
				mesh->indexes[mesh->numindexes++] = v+1;
				mesh->indexes[mesh->numindexes++] = v+2;
				mesh->indexes[mesh->numindexes++] = v+1+2;


				//x boundary
				v = mesh->numvertexes;
				mesh->numvertexes += 4;
				mesh->xyz_array[v+0][0] = (x-CHUNKBIAS + (vx+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+0][1] = (y-CHUNKBIAS + (vy+0)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+0][2] = s->heights[vx+0 + vy*SECTHEIGHTSIZE];

				mesh->xyz_array[v+1][0] = (x-CHUNKBIAS + (vx+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+1][1] = (y-CHUNKBIAS + (vy+0)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+1][2] = s->heights[(vx+1) + vy*SECTHEIGHTSIZE];

				mesh->xyz_array[v+2][0] = (x-CHUNKBIAS + (vx+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+2][1] = (y-CHUNKBIAS + (vy+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+2][2] = s->heights[(vx+0) + vy*SECTHEIGHTSIZE];

				mesh->xyz_array[v+3][0] = (x-CHUNKBIAS + (vx+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+3][1] = (y-CHUNKBIAS + (vy+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+3][2] = s->heights[(vx+1) + vy*SECTHEIGHTSIZE];

				if (s->maxh < mesh->xyz_array[v][2])
					s->maxh = mesh->xyz_array[v][2];
				if (s->minh > mesh->xyz_array[v][2])
					s->minh = mesh->xyz_array[v][2];

				st[0] = 1.0f/hm->tilecount[0] * vx;
				st[1] = 1.0f/hm->tilecount[1] * vy;
				inst[0] = 0.5f/(hm->tilecount[0]*hm->tilepixcount[0]);
				inst[1] = 0.5f/(hm->tilecount[1]*hm->tilepixcount[1]);
				mesh->st_array[v+0][0] = st[0]+inst[0];
				mesh->st_array[v+0][1] = st[1]+inst[1];
				mesh->st_array[v+1][0] = st[0]+inst[0];
				mesh->st_array[v+1][1] = st[1]-inst[1]+1.0f/hm->tilecount[1];
				mesh->st_array[v+2][0] = st[0]-inst[0]+1.0f/hm->tilecount[0];
				mesh->st_array[v+2][1] = st[1]+inst[1];
				mesh->st_array[v+3][0] = st[0]-inst[0]+1.0f/hm->tilecount[0];
				mesh->st_array[v+3][1] = st[1]-inst[1]+1.0f/hm->tilecount[1];

				//calc the position in the range -0.5 to 0.5
				mesh->lmst_array[0][v][0] = (((float)vx / (SECTHEIGHTSIZE-1))-0.5);
				mesh->lmst_array[0][v][1] = (((float)vy / (SECTHEIGHTSIZE-1))-0.5);
				//scale down to a half-texel
				mesh->lmst_array[0][v][0] *= (SECTTEXSIZE-1.0f)/HMLMSTRIDE;
				mesh->lmst_array[0][v][1] *= (SECTTEXSIZE-1.0f)/HMLMSTRIDE;
				//bias it
				mesh->lmst_array[0][v][0] += ((float)SECTTEXSIZE/(HMLMSTRIDE*2)) + ((float)(s->lmx) / HMLMSTRIDE);
				mesh->lmst_array[0][v][1] += ((float)SECTTEXSIZE/(HMLMSTRIDE*2)) + ((float)(s->lmy) / HMLMSTRIDE);


				mesh->indexes[mesh->numindexes++] = v+0;
				mesh->indexes[mesh->numindexes++] = v+2;
				mesh->indexes[mesh->numindexes++] = v+1;
				mesh->indexes[mesh->numindexes++] = v+1;
				mesh->indexes[mesh->numindexes++] = v+2;
				mesh->indexes[mesh->numindexes++] = v+1+2;

				//y boundary
				v = mesh->numvertexes;
				mesh->numvertexes += 4;
				mesh->xyz_array[v+0][0] = (x-CHUNKBIAS + (vx+0)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+0][1] = (y-CHUNKBIAS + (vy+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+0][2] = s->heights[vx + (vy+0)*SECTHEIGHTSIZE];

				mesh->xyz_array[v+1][0] = (x-CHUNKBIAS + (vx+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+1][1] = (y-CHUNKBIAS + (vy+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+1][2] = s->heights[vx + (vy+0)*SECTHEIGHTSIZE];

				mesh->xyz_array[v+2][0] = (x-CHUNKBIAS + (vx+0)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+2][1] = (y-CHUNKBIAS + (vy+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+2][2] = s->heights[vx + (vy+1)*SECTHEIGHTSIZE];

				mesh->xyz_array[v+3][0] = (x-CHUNKBIAS + (vx+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+3][1] = (y-CHUNKBIAS + (vy+1)/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v+3][2] = s->heights[vx + (vy+1)*SECTHEIGHTSIZE];

				if (s->maxh < mesh->xyz_array[v][2])
					s->maxh = mesh->xyz_array[v][2];
				if (s->minh > mesh->xyz_array[v][2])
					s->minh = mesh->xyz_array[v][2];

				st[0] = 1.0f/hm->tilecount[0] * vx;
				st[1] = 1.0f/hm->tilecount[1] * vy;
				inst[0] = 0.5f/(hm->tilecount[0]*hm->tilepixcount[0]);
				inst[1] = 0.5f/(hm->tilecount[1]*hm->tilepixcount[1]);
				mesh->st_array[v+0][0] = st[0]+inst[0];
				mesh->st_array[v+0][1] = st[1]+inst[1];
				mesh->st_array[v+1][0] = st[0]-inst[0]+1.0f/hm->tilecount[0];
				mesh->st_array[v+1][1] = st[1]+inst[1];
				mesh->st_array[v+2][0] = st[0]+inst[0];
				mesh->st_array[v+2][1] = st[1]-inst[1]+1.0f/hm->tilecount[1];
				mesh->st_array[v+3][0] = st[0]-inst[0]+1.0f/hm->tilecount[0];
				mesh->st_array[v+3][1] = st[1]-inst[1]+1.0f/hm->tilecount[1];

				//calc the position in the range -0.5 to 0.5
				mesh->lmst_array[0][v][0] = (((float)vx / (SECTHEIGHTSIZE-1))-0.5);
				mesh->lmst_array[0][v][1] = (((float)vy / (SECTHEIGHTSIZE-1))-0.5);
				//scale down to a half-texel
				mesh->lmst_array[0][v][0] *= (SECTTEXSIZE-1.0f)/HMLMSTRIDE;
				mesh->lmst_array[0][v][1] *= (SECTTEXSIZE-1.0f)/HMLMSTRIDE;
				//bias it
				mesh->lmst_array[0][v][0] += ((float)SECTTEXSIZE/(HMLMSTRIDE*2)) + ((float)(s->lmx) / HMLMSTRIDE);
				mesh->lmst_array[0][v][1] += ((float)SECTTEXSIZE/(HMLMSTRIDE*2)) + ((float)(s->lmy) / HMLMSTRIDE);

				mesh->indexes[mesh->numindexes++] = v+0;
				mesh->indexes[mesh->numindexes++] = v+2;
				mesh->indexes[mesh->numindexes++] = v+1;
				mesh->indexes[mesh->numindexes++] = v+1;
				mesh->indexes[mesh->numindexes++] = v+2;
				mesh->indexes[mesh->numindexes++] = v+1+2;
			}
		}
		break;
	case HMM_TERRAIN:
		//smooth terrain
		if (!mesh->xyz_array)
		{
			mesh->xyz_array = BZ_Malloc((sizeof(vecV_t)+sizeof(vec2_t)+sizeof(vec2_t)) * (SECTHEIGHTSIZE)*(SECTHEIGHTSIZE));
			mesh->st_array = (void*) (mesh->xyz_array + (SECTHEIGHTSIZE)*(SECTHEIGHTSIZE));
			mesh->lmst_array[0] = (void*) (mesh->st_array + (SECTHEIGHTSIZE)*(SECTHEIGHTSIZE));
		}
		mesh->colors4f_array[0] = s->colours;
		mesh->numvertexes = 0;
		/*64 quads across requires 65 verticies*/
		for (vy = 0; vy < SECTHEIGHTSIZE; vy++)
		{
			for (vx = 0; vx < SECTHEIGHTSIZE; vx++)
			{
				v = mesh->numvertexes++;
				mesh->xyz_array[v][0] = (x-CHUNKBIAS + vx/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v][1] = (y-CHUNKBIAS + vy/(SECTHEIGHTSIZE-1.0f)) * hm->sectionsize;
				mesh->xyz_array[v][2] = s->heights[vx + vy*SECTHEIGHTSIZE];

				if (s->maxh < mesh->xyz_array[v][2])
					s->maxh = mesh->xyz_array[v][2];
				if (s->minh > mesh->xyz_array[v][2])
					s->minh = mesh->xyz_array[v][2];

				mesh->st_array[v][0] = mesh->xyz_array[v][0] / 128;
				mesh->st_array[v][1] = mesh->xyz_array[v][1] / 128;

				//calc the position in the range -0.5 to 0.5
				mesh->lmst_array[0][v][0] = (((float)vx / (SECTHEIGHTSIZE-1))-0.5);
				mesh->lmst_array[0][v][1] = (((float)vy / (SECTHEIGHTSIZE-1))-0.5);
				//scale down to a half-texel
				mesh->lmst_array[0][v][0] *= (SECTTEXSIZE-1.0f)/HMLMSTRIDE;
				mesh->lmst_array[0][v][1] *= (SECTTEXSIZE-1.0f)/HMLMSTRIDE;
				//bias it
				mesh->lmst_array[0][v][0] += ((float)SECTTEXSIZE/(HMLMSTRIDE*2)) + ((float)(s->lmx) / HMLMSTRIDE);
				mesh->lmst_array[0][v][1] += ((float)SECTTEXSIZE/(HMLMSTRIDE*2)) + ((float)(s->lmy) / HMLMSTRIDE);
			}
		}

		if (!mesh->indexes)
			mesh->indexes = BZ_Malloc(sizeof(index_t) * SECTHEIGHTSIZE*SECTHEIGHTSIZE*6);

		mesh->numindexes = 0;
		for (vy = 0; vy < SECTHEIGHTSIZE-1; vy++)
		{
			for (vx = 0; vx < SECTHEIGHTSIZE-1; vx++)
			{
	#ifndef STRICTEDGES
				float d1,d2;
	#endif

	#if SECTHEIGHTSIZE == 17
				int holerow;
				int holebit;

				//skip generation of the mesh above holes
				holerow = ((vy<<3)/(SECTHEIGHTSIZE-1));
				holebit = 1u<<((vx<<3)/(SECTHEIGHTSIZE-1));
				if (s->holes[holerow] & holebit)
					continue;
	#endif
				v = vx + vy*(SECTHEIGHTSIZE);

	#ifndef STRICTEDGES
				d1 = fabs(mesh->xyz_array[v][2] - mesh->xyz_array[v+1+SECTHEIGHTSIZE][2]);
				d2 = fabs(mesh->xyz_array[v+1][2] - mesh->xyz_array[v+SECTHEIGHTSIZE][2]);
				if (d1 < d2)
				{
					mesh->indexes[mesh->numindexes++] = v+0;
					mesh->indexes[mesh->numindexes++] = v+1+SECTHEIGHTSIZE;
					mesh->indexes[mesh->numindexes++] = v+1;
					mesh->indexes[mesh->numindexes++] = v+0;
					mesh->indexes[mesh->numindexes++] = v+SECTHEIGHTSIZE;
					mesh->indexes[mesh->numindexes++] = v+1+SECTHEIGHTSIZE;
				}
				else
	#endif
				{
					mesh->indexes[mesh->numindexes++] = v+0;
					mesh->indexes[mesh->numindexes++] = v+SECTHEIGHTSIZE;
					mesh->indexes[mesh->numindexes++] = v+1;
					mesh->indexes[mesh->numindexes++] = v+1;
					mesh->indexes[mesh->numindexes++] = v+SECTHEIGHTSIZE;
					mesh->indexes[mesh->numindexes++] = v+1+SECTHEIGHTSIZE;
				}
			}
		}
		break;
	}

	//pure holes
	if (!mesh->numindexes)
	{
		memset(&s->pvscache, 0, sizeof(s->pvscache));
		return;
	}

	{
		vec3_t mins, maxs;
		mins[0] = (x-CHUNKBIAS) * hm->sectionsize;
		mins[1] = (y-CHUNKBIAS) * hm->sectionsize;
		mins[2] = s->minh;
		maxs[0] = (x+1-CHUNKBIAS) * hm->sectionsize;
		maxs[1] = (y+1-CHUNKBIAS) * hm->sectionsize;
		maxs[2] = s->maxh_cull;
		model->funcs.FindTouchedLeafs(model, &s->pvscache, mins, maxs);
	}

#ifdef GLQUAKE
	if (qrenderer == QR_OPENGL && qglGenBuffersARB)
	{
		if (!s->vbo.coord.gl.vbo)
		{
			qglGenBuffersARB(1, &s->vbo.coord.gl.vbo);
			GL_SelectVBO(s->vbo.coord.gl.vbo);
		}
		else
			GL_SelectVBO(s->vbo.coord.gl.vbo);

		qglBufferDataARB(GL_ARRAY_BUFFER_ARB, (sizeof(vecV_t)+sizeof(vec2_t)+sizeof(vec2_t)+sizeof(vec4_t)) * (mesh->numvertexes), NULL, GL_STATIC_DRAW_ARB);

		qglBufferSubDataARB(GL_ARRAY_BUFFER_ARB, 0, (sizeof(vecV_t)+sizeof(vec2_t)+sizeof(vec2_t)) * mesh->numvertexes, mesh->xyz_array);
		if (mesh->colors4f_array[0])
			qglBufferSubDataARB(GL_ARRAY_BUFFER_ARB, (sizeof(vecV_t)+sizeof(vec2_t)+sizeof(vec2_t)) * mesh->numvertexes, sizeof(vec4_t)*mesh->numvertexes,  mesh->colors4f_array[0]);
		GL_SelectVBO(0);
		s->vbo.coord.gl.addr = 0;
		s->vbo.texcoord.gl.addr = (void*)((char*)mesh->st_array - (char*)mesh->xyz_array);
		s->vbo.texcoord.gl.vbo = s->vbo.coord.gl.vbo;
		s->vbo.lmcoord[0].gl.addr = (void*)((char*)mesh->lmst_array[0] - (char*)mesh->xyz_array);
		s->vbo.lmcoord[0].gl.vbo = s->vbo.coord.gl.vbo;
		s->vbo.colours[0].gl.addr = (void*)((sizeof(vecV_t)+sizeof(vec2_t)+sizeof(vec2_t)) * mesh->numvertexes);
		s->vbo.colours[0].gl.vbo = s->vbo.coord.gl.vbo;

		if (!s->vbo.indicies.gl.vbo)
			qglGenBuffersARB(1, &s->vbo.indicies.gl.vbo);
		s->vbo.indicies.gl.addr = 0;
		GL_SelectEBO(s->vbo.indicies.gl.vbo);
		qglBufferDataARB(GL_ELEMENT_ARRAY_BUFFER_ARB, sizeof(index_t) * mesh->numindexes, mesh->indexes, GL_STATIC_DRAW_ARB);
		GL_SelectEBO(0);

#if 1
		Z_Free(mesh->xyz_array);
		mesh->xyz_array = NULL;
		mesh->st_array = NULL;
		mesh->lmst_array[0] = NULL;

		Z_Free(mesh->indexes);
		mesh->indexes = NULL;
#endif
	}
#endif
#ifdef D3D11QUAKE
	if (qrenderer == QR_DIRECT3D11)
	{
		void D3D11BE_GenBatchVBOs(vbo_t **vbochain, batch_t *firstbatch, batch_t *stopbatch);
		batch_t batch = {0};
		mesh_t *meshes = &s->mesh;
		vbo_t *vbo = NULL;
		batch.maxmeshes = 1;
		batch.mesh = &meshes;

		//BE_ClearVBO(&s->vbo);
		D3D11BE_GenBatchVBOs(&vbo, &batch, NULL);
		s->vbo = *vbo;
	}
#endif
}

struct tdibctx
{
	heightmap_t *hm;
	int vx;
	int vy;
	entity_t *ent;
	batch_t **batches;
	qbyte *pvs;
	model_t *wmodel;
};
void Terr_DrawInBounds(struct tdibctx *ctx, int x, int y, int w, int h)
{
	vec3_t mins, maxs;
	hmsection_t *s;
	struct hmwater_s *wa;
	int i;
	batch_t *b;
	heightmap_t *hm = ctx->hm;

	mins[0] = (x+0 - CHUNKBIAS)*hm->sectionsize;
	maxs[0] = (x+w - CHUNKBIAS)*hm->sectionsize;

	mins[1] = (y+0 - CHUNKBIAS)*hm->sectionsize;
	maxs[1] = (y+h - CHUNKBIAS)*hm->sectionsize;

	mins[2] = r_origin[2]-999999;
	maxs[2] = r_origin[2]+999999;
	if (R_CullBox(mins, maxs))
		return;

	if (w == 1 && h == 1)
	{
		s = Terr_GetSection(hm, x, y, TGS_LAZYLOAD);
		if (!s)
			return;

		/*move to head*/
		RemoveLink(&s->recycle);
		InsertLinkBefore(&s->recycle, &hm->recycle);

		if (s->lightmap < 0)
			Terr_LoadSection(hm, s, x, y, TGS_NODOWNLOAD);

		if (s->flags & TSF_RELIGHT)
		{
			if (!hm->relight)
			{
				hm->relight = s;
				hm->relightidx = 0;
				hm->relightmin[0] = mins[0];
				hm->relightmin[1] = mins[1];
			}
		}

		if (s->flags & TSF_DIRTY)
		{
			s->flags &= ~TSF_DIRTY;

			Terr_RebuildMesh(ctx->wmodel, s, x, y);
		}

		if (ctx->pvs && !ctx->wmodel->funcs.EdictInFatPVS(ctx->wmodel, &s->pvscache, ctx->pvs))
			return;	//this section isn't in any visible bsp leafs

		//chuck out any batches for models in this section
		for (i = 0; i < s->numents; i++)
		{
			vec3_t dist;
			float a;
			model_t *model = s->ents[i].model;
			if (!model)
				continue;

			if (model->needload == 1)
			{
				if (hm->beinglazy)
					continue;
				hm->beinglazy = true;
				Mod_LoadModel(model, MLV_WARN);
			}
			if (model->needload)
				continue;

			VectorSubtract(s->ents[i].origin, r_origin, dist);
			a = VectorLength(dist);
			a = 1024 - a + model->radius*16;
			a /= model->radius;
			if (a < 0)
				continue;
			if (a >= 1)
			{
				a = 1;
				s->ents[i].flags &= ~RF_TRANSLUCENT;
			}
			else
				s->ents[i].flags |= RF_TRANSLUCENT;
			s->ents[i].shaderRGBAf[3] = a;
			switch(model->type)
			{
			case mod_alias:
				R_GAlias_GenerateBatches(&s->ents[i], ctx->batches);
				break;
			case mod_brush:
				Surf_GenBrushBatches(ctx->batches, &s->ents[i]);
				break;
			default:	//FIXME: no sprites! oh noes!
				break;
			}
		}

		for (wa = s->water; wa; wa = wa->next)
		{
			mins[2] = wa->minheight;
			maxs[2] = wa->maxheight;
			if (!R_CullBox(mins, maxs))
			{
				Terr_DrawTerrainWater(hm, mins, maxs, wa);
			}
		}

		mins[2] = s->minh;
		maxs[2] = s->maxh;

//		if (!BoundsIntersect(mins, maxs, r_refdef.vieworg, r_refdef.vieworg))
			if (R_CullBox(mins, maxs))
				return;

		b = BE_GetTempBatch();
		if (!b)
			return;
		b->ent = ctx->ent;
		b->shader = hm->shader;
		b->flags = 0;
		b->mesh = &s->amesh;
		b->mesh[0] = &s->mesh;
		b->meshes = 1;
		b->buildmeshes = NULL;
		b->skin = &s->textures;
		b->texture = NULL;
		b->vbo = &s->vbo;
		b->lightmap[0] = s->lightmap;
		b->lightmap[1] = -1;
		b->lightmap[2] = -1;
		b->lightmap[3] = -1;

		b->next = ctx->batches[b->shader->sort];
		ctx->batches[b->shader->sort] = b;
	}
	else if (w && h)
	{
		//divide and conquer, radiating outwards from the view.
		if (w > h)
		{
			i = x + w;
			w = x + w/2;
			if (ctx->vx >= w)
			{
				Terr_DrawInBounds(ctx, w, y, i-w, h);
				Terr_DrawInBounds(ctx, x, y, w-x, h);
			}
			else
			{
				Terr_DrawInBounds(ctx, x, y, w-x, h);
				Terr_DrawInBounds(ctx, w, y, i-w, h);
			}
		}
		else
		{
			i = y + h;
			h = y + h/2;
			if (ctx->vy >= h)
			{
				Terr_DrawInBounds(ctx, x, h, w, i-h);
				Terr_DrawInBounds(ctx, x, y, w, h-y);
			}
			else
			{
				Terr_DrawInBounds(ctx, x, y, w, h-y);
				Terr_DrawInBounds(ctx, x, h, w, i-h);
			}
		}
	}
}

void Terr_DrawTerrainModel (batch_t **batches, entity_t *e)
{
	extern qbyte *frustumvis;
	model_t *m = e->model;
	heightmap_t *hm = m->terrain;
	batch_t *b;
	int bounds[4];
	struct tdibctx tdibctx;

	if (!r_refdef.recurse)
	{
		Terr_DoEditNotify(hm);
//		while (hm->activesections > 0)
//			if (!Terr_Collect(hm))
//				break;
		while (hm->activesections > TERRAINACTIVESECTIONS)
			if (!Terr_Collect(hm))
				break;
	}
	
	hm->beinglazy = false;
	if (hm->relight)
		ted_dorelight(hm);

	if (e->model == cl.worldmodel && hm->skyshader)
	{
		b = BE_GetTempBatch();
		if (b)
		{
			b->lightmap[0] = -1;
			b->lightmap[1] = -1;
			b->lightmap[2] = -1;
			b->lightmap[3] = -1;
			b->ent = e;
			b->shader = hm->skyshader;
			b->flags = 0;
			b->mesh = &hm->askymesh;
			b->mesh[0] = &hm->skymesh;
			b->meshes = 1;
			b->buildmeshes = NULL;
			b->skin = &b->shader->defaulttextures;
			b->texture = NULL;
	//		vbo = b->vbo = hm->vbo[x+y*MAXSECTIONS];
			b->vbo = NULL;

			b->next = batches[b->shader->sort];
			batches[b->shader->sort] = b;
		}
	}


	if (r_refdef.globalfog.density || gl_maxdist.value>0)
	{
		float culldist;
		extern cvar_t r_fog_exp2;

		if (r_refdef.globalfog.density)
		{
			//figure out the eyespace distance required to reach that fog value
			culldist = log(0.5/255.0f);
			if (r_fog_exp2.ival)
				culldist = sqrt(culldist / (-r_refdef.globalfog.density * r_refdef.globalfog.density));
			else
				culldist = culldist / (-r_refdef.globalfog.density);
			//anything drawn beyond this point is fully obscured by fog
			culldist += 4096;
		}
		else
			culldist = 999999999999999.f;

		if (culldist > gl_maxdist.value && gl_maxdist.value>0)
			culldist = gl_maxdist.value;

		bounds[0] = bound(hm->firstsegx, (r_refdef.vieworg[0] + (CHUNKBIAS + 0)*hm->sectionsize - culldist) / hm->sectionsize,  hm->maxsegx);
		bounds[1] = bound(hm->firstsegx, (r_refdef.vieworg[0] + (CHUNKBIAS + 1)*hm->sectionsize + culldist) / hm->sectionsize,  hm->maxsegx);
		bounds[2] = bound(hm->firstsegy, (r_refdef.vieworg[1] + (CHUNKBIAS + 0)*hm->sectionsize - culldist) / hm->sectionsize,  hm->maxsegy);
		bounds[3] = bound(hm->firstsegy, (r_refdef.vieworg[1] + (CHUNKBIAS + 1)*hm->sectionsize + culldist) / hm->sectionsize,  hm->maxsegy);
	}
	else
	{
		bounds[0] = hm->firstsegx;
		bounds[1] = hm->maxsegx;
		bounds[2] = hm->firstsegy;
		bounds[3] = hm->maxsegy;
	}

	tdibctx.hm = hm;
	tdibctx.batches = batches;
	tdibctx.ent = e;
	tdibctx.vx = (r_refdef.vieworg[0] + CHUNKBIAS*hm->sectionsize) / hm->sectionsize;
	tdibctx.vy = (r_refdef.vieworg[1] + CHUNKBIAS*hm->sectionsize) / hm->sectionsize;
	tdibctx.wmodel = e->model;
	tdibctx.pvs = (e->model == cl.worldmodel)?frustumvis:NULL;
	Terr_DrawInBounds(&tdibctx, bounds[0], bounds[2], bounds[1]-bounds[0], bounds[3]-bounds[2]);
}

typedef struct fragmentdecal_s fragmentdecal_t;

void Fragment_ClipPoly(fragmentdecal_t *dec, int numverts, float *inverts);
void Terrain_ClipDecal(fragmentdecal_t *dec, float *center, float radius, model_t *model)
{
	int min[2], max[2], mint[2], maxt[2];
	int x, y, tx, ty;
	vecV_t vert[6];
	hmsection_t *s;
	heightmap_t *hm = model->terrain; 
	min[0] = floor((center[0] - radius)/(hm->sectionsize)) + CHUNKBIAS;
	min[1] = floor((center[1] - radius)/(hm->sectionsize)) + CHUNKBIAS;
	max[0] = ceil((center[0] + radius)/(hm->sectionsize)) + CHUNKBIAS;
	max[1] = ceil((center[1] + radius)/(hm->sectionsize)) + CHUNKBIAS;

	min[0] = bound(hm->firstsegx, min[0], hm->maxsegx);
	min[1] = bound(hm->firstsegy, min[1], hm->maxsegy);
	max[0] = bound(hm->firstsegx, max[0], hm->maxsegx);
	max[1] = bound(hm->firstsegy, max[1], hm->maxsegy);

	for (y = min[1]; y < max[1]; y++)
	{
		for (x = min[0]; x < max[0]; x++)
		{
			s = Terr_GetSection(hm, x, y, TGS_LOAD);
			if (!s)
				continue;

			mint[0] = floor((center[0] - radius)*(SECTHEIGHTSIZE-1)/(hm->sectionsize) + (CHUNKBIAS - x)*(SECTHEIGHTSIZE-1));
			mint[1] = floor((center[1] - radius)*(SECTHEIGHTSIZE-1)/(hm->sectionsize) + (CHUNKBIAS - y)*(SECTHEIGHTSIZE-1));
			maxt[0] =  ceil((center[0] + radius)*(SECTHEIGHTSIZE-1)/(hm->sectionsize) + (CHUNKBIAS - x)*(SECTHEIGHTSIZE-1));
			maxt[1] =  ceil((center[1] + radius)*(SECTHEIGHTSIZE-1)/(hm->sectionsize) + (CHUNKBIAS - y)*(SECTHEIGHTSIZE-1));

			mint[0] = bound(0, mint[0], (SECTHEIGHTSIZE-1));
			mint[1] = bound(0, mint[1], (SECTHEIGHTSIZE-1));
			maxt[0] = bound(0, maxt[0], (SECTHEIGHTSIZE-1));
			maxt[1] = bound(0, maxt[1], (SECTHEIGHTSIZE-1));

			for (ty = mint[1]; ty < maxt[1]; ty++)
			{
				for (tx = mint[0]; tx < maxt[0]; tx++)
				{
#ifndef STRICTEDGES
					float d1, d2;
					d1 = fabs(s->heights[(tx+0) + (ty+0)*SECTHEIGHTSIZE] - s->heights[(tx+1) + (ty+1)*SECTHEIGHTSIZE]);
					d2 = fabs(s->heights[(tx+1) + (ty+0)*SECTHEIGHTSIZE] - s->heights[(tx+0) + (ty+1)*SECTHEIGHTSIZE]);
					if (d1 < d2)
					{
						vert[0][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[0][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;
						vert[1][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[1][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;
						vert[2][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[2][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;

						vert[3][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[3][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;
						vert[4][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[4][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;
						vert[5][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[5][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;

						vert[0][2] = s->heights[(tx+0) + (ty+0)*SECTHEIGHTSIZE];
						vert[1][2] = s->heights[(tx+1) + (ty+1)*SECTHEIGHTSIZE];
						vert[2][2] = s->heights[(tx+1) + (ty+0)*SECTHEIGHTSIZE];
						vert[3][2] = s->heights[(tx+0) + (ty+0)*SECTHEIGHTSIZE];
						vert[4][2] = s->heights[(tx+0) + (ty+1)*SECTHEIGHTSIZE];
						vert[5][2] = s->heights[(tx+1) + (ty+1)*SECTHEIGHTSIZE];
					}
					else
#endif
					{
						vert[0][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[0][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;
						vert[1][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[1][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;
						vert[2][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[2][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;

						vert[3][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[3][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;
						vert[4][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+0)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[4][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;
						vert[5][0] = (x-CHUNKBIAS)*hm->sectionsize + (tx+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;vert[5][1] = (y-CHUNKBIAS)*hm->sectionsize + (ty+1)/(float)(SECTHEIGHTSIZE-1)*hm->sectionsize;

						vert[0][2] = s->heights[(tx+0) + (ty+0)*SECTHEIGHTSIZE];
						vert[1][2] = s->heights[(tx+0) + (ty+1)*SECTHEIGHTSIZE];
						vert[2][2] = s->heights[(tx+1) + (ty+0)*SECTHEIGHTSIZE];
						vert[3][2] = s->heights[(tx+1) + (ty+0)*SECTHEIGHTSIZE];
						vert[4][2] = s->heights[(tx+0) + (ty+1)*SECTHEIGHTSIZE];
						vert[5][2] = s->heights[(tx+1) + (ty+1)*SECTHEIGHTSIZE];
					}

					Fragment_ClipPoly(dec, 3, &vert[0][0]);
					Fragment_ClipPoly(dec, 3, &vert[3][0]);
				}
			}
		}
	}
}

#endif

unsigned int Heightmap_PointContentsHM(heightmap_t *hm, float clipmipsz, vec3_t org)
{
	float x, y;
	float z, tz;
	int sx, sy;
	unsigned int holerow;
	unsigned int holebit;
	hmsection_t *s;
	struct hmwater_s *w;
	unsigned int contents;
	const float wbias = CHUNKBIAS * hm->sectionsize;

	sx = (org[0]+wbias)/hm->sectionsize;
	sy = (org[1]+wbias)/hm->sectionsize;
	if (sx < hm->firstsegx || sy < hm->firstsegy)
		return hm->exteriorcontents;
	if (sx >= hm->maxsegx || sy >= hm->maxsegy)
		return hm->exteriorcontents;
	s = Terr_GetSection(hm, sx, sy, TGS_LOAD);
	if (!s)
	{
		return FTECONTENTS_SOLID;
	}

	x = (org[0]+wbias - (sx*hm->sectionsize))*(SECTHEIGHTSIZE-1)/hm->sectionsize;
	y = (org[1]+wbias - (sy*hm->sectionsize))*(SECTHEIGHTSIZE-1)/hm->sectionsize;
	z = (org[2]+clipmipsz);

	if (z < s->minh-16)
		return hm->exteriorcontents;

	sx = x; x-=sx;
	sy = y; y-=sy;

	holerow = ((sy<<3)/(SECTHEIGHTSIZE-1));
	holebit = 1u<<((sx<<3)/(SECTHEIGHTSIZE-1));
	if (s->holes[holerow] & (1u<<holebit))
		return FTECONTENTS_EMPTY;

	//made of two triangles:
	if (x+y>1)	//the 1, 1 triangle
	{
		float v1, v2, v3;
		v3 = 1-y;
		v2 = x+y-1;
		v1 = 1-x;
		//0, 1
		//1, 1
		//1, 0
		tz = (s->heights[(sx+0)+(sy+1)*SECTHEIGHTSIZE]*v1 +
			  s->heights[(sx+1)+(sy+1)*SECTHEIGHTSIZE]*v2 +
			  s->heights[(sx+1)+(sy+0)*SECTHEIGHTSIZE]*v3);
	}
	else
	{
		float v1, v2, v3;
		v1 = y;
		v2 = x;
		v3 = 1-y-x;

		//0, 1
		//1, 0
		//0, 0
		tz = (s->heights[(sx+0)+(sy+1)*SECTHEIGHTSIZE]*v1 +
			  s->heights[(sx+1)+(sy+0)*SECTHEIGHTSIZE]*v2 +
			  s->heights[(sx+0)+(sy+0)*SECTHEIGHTSIZE]*v3);
	}
	if (z <= tz)
		return FTECONTENTS_SOLID;	//contained within

	contents = FTECONTENTS_EMPTY;
	for (w = s->water; w; w = w->next)
	{
		if (w->holes[holerow] & (1u<<holebit))
			continue;
		if (z < w->maxheight)	//FIXME
			contents |= w->contentmask;
	}
	return contents;
}

unsigned int Heightmap_PointContents(model_t *model, vec3_t axis[3], vec3_t org)
{
	heightmap_t *hm = model->terrain;
	return Heightmap_PointContentsHM(hm, 0, org);
}
unsigned int Heightmap_NativeBoxContents(model_t *model, int hulloverride, int frame, vec3_t axis[3], vec3_t org, vec3_t mins, vec3_t maxs)
{
	heightmap_t *hm = model->terrain;
	return Heightmap_PointContentsHM(hm, mins[2], org);
}

void Heightmap_Normal(heightmap_t *hm, vec3_t org, vec3_t norm)
{
#if 0
	norm[0] = 0;
	norm[1] = 0;
	norm[2] = 1;
#else
	float x, y;
	int sx, sy;
	vec3_t d1, d2;
	const float wbias = CHUNKBIAS * hm->sectionsize;
	hmsection_t *s;

	norm[0] = 0;
	norm[1] = 0;
	norm[2] = 1;

	sx = (org[0]+wbias)/hm->sectionsize;
	sy = (org[1]+wbias)/hm->sectionsize;
	if (sx < hm->firstsegx || sy < hm->firstsegy)
		return;
	if (sx >= hm->maxsegx || sy >= hm->maxsegy)
		return;
	s = Terr_GetSection(hm, sx, sy, TGS_LOAD);
	if (!s)
		return;

	x = (org[0]+wbias - (sx*hm->sectionsize))*(SECTHEIGHTSIZE-1)/hm->sectionsize;
	y = (org[1]+wbias - (sy*hm->sectionsize))*(SECTHEIGHTSIZE-1)/hm->sectionsize;

	sx = x; x-=sx;
	sy = y; y-=sy;

	if (x+y>1)	//the 1, 1 triangle
	{
		//0, 1
		//1, 1
		//1, 0
		d1[0] = (hm->sectionsize / SECTHEIGHTSIZE);
		d1[1] = 0;
		d1[2] = (s->heights[(sx+1)+(sy+1)*SECTHEIGHTSIZE] - s->heights[(sx+0)+(sy+1)*SECTHEIGHTSIZE]);
		d2[0] = 0;
		d2[1] = (hm->sectionsize / SECTHEIGHTSIZE);
		d2[2] = (s->heights[(sx+1)+(sy+1)*SECTHEIGHTSIZE] - s->heights[(sx+1)+(sy+0)*SECTHEIGHTSIZE]);
	}
	else
	{	//the 0,0 triangle
		//0, 1
		//1, 0
		//0, 0
		d1[0] = (hm->sectionsize / SECTHEIGHTSIZE);
		d1[1] = 0;
		d1[2] = (s->heights[(sx+1)+(sy+0)*SECTHEIGHTSIZE] - s->heights[(sx+0)+(sy+0)*SECTHEIGHTSIZE]);
		d2[0] = 0;
		d2[1] = (hm->sectionsize / SECTHEIGHTSIZE);
		d2[2] = (s->heights[(sx+0)+(sy+1)*SECTHEIGHTSIZE] - s->heights[(sx+0)+(sy+0)*SECTHEIGHTSIZE]);
	}

	VectorNormalize(d1);
	VectorNormalize(d2);
	CrossProduct(d1, d2, norm);
	VectorNormalize(norm);
#endif
}

typedef struct {
	vec3_t start;
	vec3_t end;
	vec3_t impact;
	vec4_t plane;
	vec3_t mins;
	vec3_t maxs;
	float frac;
	float htilesize;
	heightmap_t *hm;
	int contents;
	int hitcontentsmask;
} hmtrace_t;

static void Heightmap_Trace_Brush(hmtrace_t *tr, vec4_t *planes, int numplanes)
{
	qboolean startout;
	float *enterplane;
	double enterfrac, exitfrac, nearfrac=0;
	double enterdist=0;
	double dist, d1, d2, f;
	int i;

	startout = false;
	enterplane= NULL;
	enterfrac = -1;
	exitfrac = 10;
	for (i = 0; i < numplanes; i++)
	{
		/*calculate the distance based upon the shape of the object we're tracing for*/
		dist = planes[i][3];


		d1 = DotProduct (tr->start, planes[i]) - dist;
		d2 = DotProduct (tr->end, planes[i]) - dist;

		//if we're fully outside any plane, then we cannot possibly enter the brush, skip to the next one
		if (d1 > 0 && d2 >= d1)
			return;

		if (d1 > 0)
			startout = true;

		//if we're fully inside the plane, then whatever is happening is not relevent for this plane
		if (d1 <= 0 && d2 <= 0)
			continue;

		f = (d1) / (d1-d2);
		if (d1 > d2)
		{
			//entered the brush. favour the furthest fraction to avoid extended edges (yay for convex shapes)
			if (enterfrac < f)
			{
				enterfrac = f;
				nearfrac = (d1 - (0.03125)) / (d1-d2);
				enterplane = planes[i];
				enterdist = dist;
			}
		}
		else
		{
			//left the brush, favour the nearest plane (smallest frac)
			if (exitfrac > f)
			{
				exitfrac = f;
			}
		}
	}

	if (!startout)
	{
		tr->frac = -1;
		return;
	}
	if (enterfrac != -1 && enterfrac < exitfrac)
	{
		//impact!
		if (enterfrac < tr->frac)
		{
			if (nearfrac < 0)
				nearfrac = 0;
			tr->frac = nearfrac;//enterfrac;
			tr->plane[3] = enterdist;
			VectorCopy(enterplane, tr->plane);
		}
	}
}

//sx,sy are the tile coord
//note that tile SECTHEIGHTSIZE-1 does not exist, as the last sample overlaps the first sample of the next section
static void Heightmap_Trace_Square(hmtrace_t *tr, int tx, int ty)
{
	vec3_t d[2];
	vec3_t p[4];
	vec4_t n[5];
	int t;
//	int i;

#ifndef STRICTEDGES
	float d1, d2;
#endif
	int sx, sy;
	hmsection_t *s;
	unsigned int holerow;
	unsigned int holebit;

	sx = tx/(SECTHEIGHTSIZE-1);
	sy = ty/(SECTHEIGHTSIZE-1);
	if (sx < tr->hm->firstsegx || sx >= tr->hm->maxsegx)
		s = NULL;
	else if (sy < tr->hm->firstsegy || sy >= tr->hm->maxsegy)
		s = NULL;
	else
		s = Terr_GetSection(tr->hm, sx, sy, TGS_LOAD);

	if (!s)
	{
		//you're not allowed to walk into sections that have not loaded.
		//might as well check the entire section instead of just one tile
		Vector4Set(n[0],  1, 0, 0, (tx/(SECTHEIGHTSIZE-1) + 1 - CHUNKBIAS)*tr->hm->sectionsize);
		Vector4Set(n[1], -1, 0, 0, -(tx/(SECTHEIGHTSIZE-1) + 0 - CHUNKBIAS)*tr->hm->sectionsize);
		Vector4Set(n[2], 0,  1, 0, (ty/(SECTHEIGHTSIZE-1) + 1 - CHUNKBIAS)*tr->hm->sectionsize);
		Vector4Set(n[3], 0, -1, 0, -(ty/(SECTHEIGHTSIZE-1) + 0 - CHUNKBIAS)*tr->hm->sectionsize);
		Heightmap_Trace_Brush(tr, n, 4);
		return;
	}
/*
	for (i = 0; i < s->numents; i++)
	{
		vec3_t start_l, end_l;
		trace_t etr;
		model_t *model = s->ents[i].model;
		int frame = s->ents[i].framestate.g[FS_REG].frame[0];
		if (!model || model->needload || !model->funcs.NativeTrace)
			continue;
		VectorSubtract (tr->start, s->ents[i].origin, start_l);
		VectorSubtract (tr->end, s->ents[i].origin, end_l);
		start_l[2] -= tr->mins[2];
		end_l[2] -= tr->mins[2];
		VectorScale(start_l, s->ents[i].scale, start_l);
		VectorScale(end_l, s->ents[i].scale, end_l);

		memset(&etr, 0, sizeof(etr));
		etr.fraction = 1;
		if (model->funcs.NativeTrace (model, 0, frame, s->ents[i].axis, start_l, end_l, tr->mins, tr->maxs, tr->hitcontentsmask, &etr))
		{
			if (etr.fraction < tr->frac)
			{
				tr->contents = etr.contents;
				tr->frac = etr.fraction;
				tr->plane[3] = etr.plane.dist;
				tr->plane[0] = etr.plane.normal[0];
				tr->plane[1] = etr.plane.normal[1];
				tr->plane[2] = etr.plane.normal[2];
			}
		}
	}
*/
	sx = tx - CHUNKBIAS*(SECTHEIGHTSIZE-1);
	sy = ty - CHUNKBIAS*(SECTHEIGHTSIZE-1);

	tx = tx % (SECTHEIGHTSIZE-1);
	ty = ty % (SECTHEIGHTSIZE-1);

	holerow = ((ty<<3)/(SECTHEIGHTSIZE-1));
	holebit = 1u<<((tx<<3)/(SECTHEIGHTSIZE-1));
	if (s->holes[holerow] & holebit)
		return;	//no collision with holes

	switch(tr->hm->mode)
	{
	case HMM_BLOCKS:
		//left-most
		Vector4Set(n[0], -1, 0, 0, -tr->htilesize*(sx+0));
		//bottom-most
		Vector4Set(n[1], 0, 1, 0, tr->htilesize*(sy+1));
		//right-most
		Vector4Set(n[2], 1, 0, 0, tr->htilesize*(sx+1));
		//top-most
		Vector4Set(n[3], 0, -1, 0, -tr->htilesize*(sy+0));
		//top
		Vector4Set(n[4], 0, 0, 1, s->heights[(tx+0)+(ty+0)*SECTHEIGHTSIZE]);

		Heightmap_Trace_Brush(tr, n, 5);
		return;
	case HMM_TERRAIN:
		VectorSet(p[0], tr->htilesize*(sx+0), tr->htilesize*(sy+0), s->heights[(tx+0)+(ty+0)*SECTHEIGHTSIZE]);
		VectorSet(p[1], tr->htilesize*(sx+1), tr->htilesize*(sy+0), s->heights[(tx+1)+(ty+0)*SECTHEIGHTSIZE]);
		VectorSet(p[2], tr->htilesize*(sx+0), tr->htilesize*(sy+1), s->heights[(tx+0)+(ty+1)*SECTHEIGHTSIZE]);
		VectorSet(p[3], tr->htilesize*(sx+1), tr->htilesize*(sy+1), s->heights[(tx+1)+(ty+1)*SECTHEIGHTSIZE]);

#ifndef STRICTEDGES
		d1 = fabs(p[0][2] - p[3][2]);
		d2 = fabs(p[1][2] - p[2][2]);
		if (d1 < d2)
		{
			for (t = 0; t < 2; t++)
			{
				/*generate the brush (in world space*/
				if (t == 0)
				{
					VectorSubtract(p[3], p[2], d[0]);
					VectorSubtract(p[2], p[0], d[1]);
					//left-most
					Vector4Set(n[0], -1, 0, 0, -tr->htilesize*(sx+0));
					//bottom-most
					Vector4Set(n[1], 0, 1, 0, tr->htilesize*(sy+1));
					//top-right
					VectorSet(n[2], 0.70710678118654752440084436210485, -0.70710678118654752440084436210485, 0);
					n[2][3] = DotProduct(n[2], p[0]);
					//top
					VectorNormalize(d[0]);
					VectorNormalize(d[1]);
					CrossProduct(d[0], d[1], n[3]);
					VectorNormalize(n[3]);
					n[3][3] = DotProduct(n[3], p[0]);
					//down
					VectorNegate(n[3], n[4]);
					n[4][3] = DotProduct(n[4], p[0]) - n[4][2]*TERRAINTHICKNESS;
				}
				else
				{
					VectorSubtract(p[1], p[0], d[0]);
					VectorSubtract(p[3], p[1], d[1]);

					//right-most
					Vector4Set(n[0], 1, 0, 0, tr->htilesize*(sx+1));
					//top-most
					Vector4Set(n[1], 0, -1, 0, -tr->htilesize*(sy+0));
					//bottom-left
					VectorSet(n[2], -0.70710678118654752440084436210485, 0.70710678118654752440084436210485, 0);
					n[2][3] = DotProduct(n[2], p[0]);
					//top
					VectorNormalize(d[0]);
					VectorNormalize(d[1]);
					CrossProduct(d[0], d[1], n[3]);
					VectorNormalize(n[3]);
					n[3][3] = DotProduct(n[3], p[0]);
					//down
					VectorNegate(n[3], n[4]);
					n[4][3] = DotProduct(n[4], p[0]) - n[4][2]*TERRAINTHICKNESS;
				}
				Heightmap_Trace_Brush(tr, n, 5);
			}
		}
		else
#endif
		{
			for (t = 0; t < 2; t++)
			{
				/*generate the brush (in world space*/
				if (t == 0)
				{
					VectorSubtract(p[1], p[0], d[0]);
					VectorSubtract(p[2], p[0], d[1]);
					//left-most
					Vector4Set(n[0], -1, 0, 0, -tr->htilesize*(sx+0));
					//top-most
					Vector4Set(n[1], 0, -1, 0, -tr->htilesize*(sy+0));
					//bottom-right
					VectorSet(n[2], 0.70710678118654752440084436210485, 0.70710678118654752440084436210485, 0);
					n[2][3] = DotProduct(n[2], p[1]);
					//top
					VectorNormalize(d[0]);
					VectorNormalize(d[1]);
					CrossProduct(d[0], d[1], n[3]);
					VectorNormalize(n[3]);
					n[3][3] = DotProduct(n[3], p[1]);
					//down
					VectorNegate(n[3], n[4]);
					n[4][3] = DotProduct(n[4], p[1]) - n[4][2]*TERRAINTHICKNESS;
				}
				else
				{
					VectorSubtract(p[3], p[2], d[0]);
					VectorSubtract(p[3], p[1], d[1]);

					//right-most
					Vector4Set(n[0], 1, 0, 0, tr->htilesize*(sx+1));
					//bottom-most
					Vector4Set(n[1], 0, 1, 0, tr->htilesize*(sy+1));
					//top-left
					VectorSet(n[2], -0.70710678118654752440084436210485, -0.70710678118654752440084436210485, 0);
					n[2][3] = DotProduct(n[2], p[1]);
					//top
					VectorNormalize(d[0]);
					VectorNormalize(d[1]);
					CrossProduct(d[0], d[1], n[3]);
					VectorNormalize(n[3]);
					n[3][3] = DotProduct(n[3], p[1]);
					//down
					VectorNegate(n[3], n[4]);
					n[4][3] = DotProduct(n[4], p[1]) - n[4][2]*TERRAINTHICKNESS;
				}
				Heightmap_Trace_Brush(tr, n, 5);
			}
		}
		break;
	}
}

#define DIST_EPSILON 0
/*
Heightmap_TraceRecurse
Traces an arbitary box through a heightmap. (interface with outside)

Why is recursion good?
1: it is consistant with bsp models. :)
2: it allows us to use any size model we want
3: we don't have to work out the height of the terrain every X units, but can be more precise.

Obviously, we don't care all that much about 1
*/
qboolean Heightmap_Trace(struct model_s *model, int hulloverride, int frame, vec3_t mataxis[3], vec3_t start, vec3_t end, vec3_t mins, vec3_t maxs, unsigned int against, struct trace_s *trace)
{
	vec2_t pos, npos;
	qboolean nudge[2];
	vec2_t dir;
	vec2_t frac;
	vec2_t emins;
	vec2_t emaxs;
	int x, y;
	int axis;
	int breaklimit = 1000;
	float wbias;
	hmtrace_t hmtrace;
	hmtrace.hm = model->terrain;
	hmtrace.htilesize = hmtrace.hm->sectionsize / (SECTHEIGHTSIZE-1);
	hmtrace.frac = 1;
	hmtrace.contents = 0;

	hmtrace.plane[0] = 0;
	hmtrace.plane[1] = 0;
	hmtrace.plane[2] = 0;
	hmtrace.plane[3] = 0;

	memset(trace, 0, sizeof(*trace));
	trace->fraction = 1;

	//to tile space
	hmtrace.start[0] = (start[0]);
	hmtrace.start[1] = (start[1]);
	hmtrace.start[2] = (start[2] + mins[2]);
	hmtrace.end[0] = (end[0]);
	hmtrace.end[1] = (end[1]);
	hmtrace.end[2] = (end[2] + mins[2]);

	dir[0] = (hmtrace.end[0] - hmtrace.start[0])/hmtrace.htilesize;
	dir[1] = (hmtrace.end[1] - hmtrace.start[1])/hmtrace.htilesize;
	pos[0] = (hmtrace.start[0]+CHUNKBIAS*hmtrace.hm->sectionsize)/hmtrace.htilesize;
	pos[1] = (hmtrace.start[1]+CHUNKBIAS*hmtrace.hm->sectionsize)/hmtrace.htilesize;
	wbias = CHUNKBIAS*hmtrace.hm->sectionsize;

	emins[0] = (mins[0]-1.5)/hmtrace.htilesize;
	emins[1] = (mins[1]-1.5)/hmtrace.htilesize;
	emaxs[0] = (maxs[0]+1.5)/hmtrace.htilesize;
	emaxs[1] = (maxs[1]+1.5)/hmtrace.htilesize;

	VectorCopy(mins, hmtrace.mins);
	VectorCopy(maxs, hmtrace.maxs);

	/*fixme:
	set pos to the leading corner instead
	on boundary changes, scan across multiple blocks
	*/

	//make sure the start tile is valid
	for (y = pos[1] + emins[1]; y <= pos[1] + emaxs[1]; y++)
		for (x = pos[0] + emins[0]; x <= pos[0] + emaxs[0]; x++)
			Heightmap_Trace_Square(&hmtrace, x, y);
	for(;;)
	{
		if (breaklimit--< 0)
			break;
		for (axis = 0; axis < 2; axis++)
		{
			if (dir[axis] > 0)
			{
				nudge[axis] = false;
				npos[axis] = pos[axis] + 1-(pos[axis]-(int)pos[axis]);
				frac[axis] = (npos[axis]*hmtrace.htilesize-wbias - hmtrace.start[axis])/(hmtrace.end[axis]-hmtrace.start[axis]);
			}
			else if (dir[axis] < 0)
			{
				npos[axis] = pos[axis];
				nudge[axis] = (float)(int)pos[axis] == pos[axis];
				npos[axis] = (int)npos[axis];
				frac[axis] = (npos[axis]*hmtrace.htilesize-wbias - hmtrace.start[axis])/(hmtrace.end[axis]-hmtrace.start[axis]);
				npos[axis] -= nudge[axis];
			}
			else
				frac[axis] = 1000000000000000.0;
		}

		//which side are we going down?
		if (frac[0] < frac[1])
			axis = 0;
		else
			axis = 1;

		if (frac[axis] >= 1)
			break;

		//touch the neighbour(s)
		if (dir[axis] > 0)
		{
			pos[axis] = (int)pos[axis] + 1;
			pos[axis] = npos[axis];
			Heightmap_Trace_Square(&hmtrace, pos[0], pos[1]);
		}
		else
		{
			pos[axis] = npos[axis];
			Heightmap_Trace_Square(&hmtrace, pos[0], pos[1]);
		}
		//and make sure our position on the other axis is correct, for the next time around the loop
		if (frac[axis] > hmtrace.frac)
			break;
		pos[!axis] = ((hmtrace.end[!axis] * frac[axis]) + (hmtrace.start[!axis] * (1-frac[axis])) + CHUNKBIAS*hmtrace.hm->sectionsize)/hmtrace.htilesize;
	}

	trace->plane.dist = hmtrace.plane[3];
	trace->plane.normal[0] = hmtrace.plane[0];
	trace->plane.normal[1] = hmtrace.plane[1];
	trace->plane.normal[2] = hmtrace.plane[2];

	if (hmtrace.frac == -1)
	{
		trace->fraction = 0;
		trace->startsolid = true;
		trace->allsolid = true;
		VectorCopy(start, trace->endpos);
	}
	else
	{
		if (hmtrace.frac < 0)
			hmtrace.frac = 0;
		trace->fraction = hmtrace.frac;
		VectorInterpolate(start, hmtrace.frac, end, trace->endpos);
	}
	return trace->fraction < 1;
}

typedef struct
{
	int id;
	int x, y;
} hmpvs_t;
unsigned int Heightmap_FatPVS		(model_t *mod, vec3_t org, qbyte *pvsbuffer, unsigned int pvssize, qboolean add)
{
	//embed the org onto the pvs
	hmpvs_t *hmpvs = (hmpvs_t*)pvsbuffer;
	hmpvs->id = 0xdeadbeef;
	hmpvs->x = org[0];
	hmpvs->y = org[1];
	return sizeof(*hmpvs);
}

#ifndef CLIENTONLY
qboolean Heightmap_EdictInFatPVS	(model_t *mod, struct pvscache_s *edict, qbyte *pvsdata)
{
	int x,y;
	hmpvs_t *hmpvs = (hmpvs_t*)pvsdata;
	//check distance
	x = edict->areanum - hmpvs->x;
	y = edict->areanum2 - hmpvs->y;

	return (x*x+y*y) < 4096*4096;
}

void Heightmap_FindTouchedLeafs	(model_t *mod, pvscache_t *ent, float *mins, float *maxs)
{
	ent->areanum = (mins[0] + maxs[0]) * 0.5;
	ent->areanum2 = (mins[1] + maxs[1]) * 0.5;
}
#endif

void Heightmap_LightPointValues	(model_t *mod, vec3_t point, vec3_t res_diffuse, vec3_t res_ambient, vec3_t res_dir)
{
	float time = realtime;

	res_diffuse[0] = 128;
	res_diffuse[1] = 128;
	res_diffuse[2] = 128;
	res_ambient[0] = 64;
	res_ambient[1] = 64;
	res_ambient[2] = 64;
	res_dir[0] = sin(time);
	res_dir[1] = cos(time);
	res_dir[2] = sin(time);
	VectorNormalize(res_dir);
}
void Heightmap_StainNode			(mnode_t *node, float *parms)
{
}
void Heightmap_MarkLights			(dlight_t *light, int bit, mnode_t *node)
{
}

qbyte *Heightmap_LeafnumPVS	(model_t *model, int num, qbyte *buffer, unsigned int buffersize)
{
	static qbyte heightmappvs = 255;
	return &heightmappvs;
}
int	Heightmap_LeafForPoint	(model_t *model, vec3_t point)
{
	return 0;
}

#ifndef SERVERONLY
static unsigned char *ted_getlightmap(hmsection_t *s, int idx)
{
	unsigned char *lm;
	int x = idx % SECTTEXSIZE, y = idx / SECTTEXSIZE;
	if (s->lightmap < 0)
	{
		Terr_LoadSection(s->hmmod, s, x, y, true);
		Terr_InitLightmap(s, true);
	}

	s->flags |= TSF_EDITED;

	lightmap[s->lightmap]->modified = true;
	lightmap[s->lightmap]->rectchange.l = 0;
	lightmap[s->lightmap]->rectchange.t = 0;
	lightmap[s->lightmap]->rectchange.w = HMLMSTRIDE;
	lightmap[s->lightmap]->rectchange.h = HMLMSTRIDE;
	lm = lightmap[s->lightmap]->lightmaps;
	lm += ((s->lmy+y) * HMLMSTRIDE + (s->lmx+x)) * lightmap_bytes;
	return lm;
}
static void ted_dorelight(heightmap_t *hm)
{
	unsigned char *lm = ted_getlightmap(hm->relight, 0);
	int x, y;
#define EXPAND 2
	vec3_t surfnorms[(SECTTEXSIZE+EXPAND*2)*(SECTTEXSIZE+EXPAND*2)];
//	float scaletab[EXPAND*2*EXPAND*2];
	vec3_t ldir = {0.4, 0.7, 2};
	hmsection_t *s = hm->relight;
	s->flags &= ~TSF_RELIGHT;
	hm->relight = NULL;

	if (s->lightmap < 0)
		return;

	for (y = -EXPAND; y < SECTTEXSIZE+EXPAND; y++)
	for (x = -EXPAND; x < SECTTEXSIZE+EXPAND; x++)
	{
		vec3_t pos;
		pos[0] = hm->relightmin[0] + (x*hm->sectionsize/(SECTTEXSIZE-1));
		pos[1] = hm->relightmin[1] + (y*hm->sectionsize/(SECTTEXSIZE-1));
		pos[2] = 0;
		Heightmap_Normal(s->hmmod, pos, surfnorms[x+EXPAND + (y+EXPAND)*(SECTTEXSIZE+EXPAND*2)]);
	}

	VectorNormalize(ldir);

	for (y = 0; y < SECTTEXSIZE; y++, lm += (HMLMSTRIDE-SECTTEXSIZE)*4)
	for (x = 0; x < SECTTEXSIZE; x++, lm += 4)
	{
		vec3_t norm;
		float d;
		int sx,sy;
		VectorClear(norm);
		for (sy = -EXPAND; sy <= EXPAND; sy++)
		for (sx = -EXPAND; sx <= EXPAND; sx++)
		{
			d = sqrt((EXPAND*2+1)*(EXPAND*2+1) - sx*sx+sy*sy);
			VectorMA(norm, d, surfnorms[x+sx+EXPAND + (y+sy+EXPAND)*(SECTTEXSIZE+EXPAND*2)], norm);
		}

		VectorNormalize(norm);
		d = DotProduct(ldir, norm);
		if (d < 0)
			d = 0;
//		lm[0] = norm[0]*127 + 128;
//		lm[1] = norm[1]*127 + 128;
//		lm[2] = norm[2]*127 + 128;
		lm[3] = d*255;
	}

	lightmap[s->lightmap]->modified = true;
	lightmap[s->lightmap]->rectchange.l = 0;
	lightmap[s->lightmap]->rectchange.t = 0;
	lightmap[s->lightmap]->rectchange.w = HMLMSTRIDE;
	lightmap[s->lightmap]->rectchange.h = HMLMSTRIDE;
}
static void ted_sethole(void *ctx, hmsection_t *s, int idx, float wx, float wy, float w)
{
	unsigned int row = idx/9;
	unsigned int col = idx%9;
	unsigned int bit;
	unsigned int mask;
	if (row == 8 || col == 8)
		return;	//meh, our painting function is written with an overlap of 1
	if (w <= 0)
		return;
	mask = 1u<<(col);
	if (*(float*)ctx > 0)
		bit = mask;
	else
		bit = 0;
	s->flags |= TSF_NOTIFY|TSF_DIRTY|TSF_EDITED;
	s->holes[row] = (s->holes[row] & ~mask) | bit;
}
static void ted_heighttally(void *ctx, hmsection_t *s, int idx, float wx, float wy, float w)
{
	/*raise the terrain*/
	((float*)ctx)[0] += s->heights[idx]*w;
	((float*)ctx)[1] += w;
}
static void ted_heightsmooth(void *ctx, hmsection_t *s, int idx, float wx, float wy, float w)
{
	s->flags |= TSF_NOTIFY|TSF_DIRTY|TSF_EDITED|TSF_RELIGHT;
	/*interpolate the terrain towards a certain value*/

	if (IS_NAN(s->heights[idx]))
		s->heights[idx] = *(float*)ctx;
	else
		s->heights[idx] = s->heights[idx]*(1-w) + w**(float*)ctx;
}
static void ted_heightraise(void *ctx, hmsection_t *s, int idx, float wx, float wy, float strength)
{
	s->flags |= TSF_NOTIFY|TSF_DIRTY|TSF_EDITED|TSF_RELIGHT;
	/*raise the terrain*/
	s->heights[idx] += strength;
}
static void ted_heightset(void *ctx, hmsection_t *s, int idx, float wx, float wy, float strength)
{
	s->flags |= TSF_NOTIFY|TSF_DIRTY|TSF_EDITED|TSF_RELIGHT;
	/*set the terrain to a specific value*/
	s->heights[idx] = *(float*)ctx;
}

static void ted_waterset(void *ctx, hmsection_t *s, int idx, float wx, float wy, float strength)
{
	struct hmwater_s *w = s->water;
	if (!w)
		w = Terr_GenerateWater(s, *(float*)ctx);
	s->flags |= TSF_NOTIFY|TSF_DIRTY|TSF_EDITED;

	//FIXME: water doesn't render properly. don't let people make dodgy water regions because they can't see it.
	//this is temp code.
	//for (idx = 0; idx < 9*9; idx++)
		//w->heights[idx] = *(float*)ctx;
	//end fixme

	w->heights[idx] = *(float*)ctx;
	if (w->minheight > w->heights[idx])
		w->minheight = w->heights[idx];
	if (w->maxheight < w->heights[idx])
		w->maxheight = w->heights[idx];

	//FIXME: what about holes?
}

static void ted_mixconcentrate(void *ctx, hmsection_t *s, int idx, float wx, float wy, float w)
{
	unsigned char *lm = ted_getlightmap(s, idx);
	s->flags |= TSF_NOTIFY|TSF_EDITED;

	/*concentrate the lightmap values to a single channel*/
	if (lm[0] > lm[1] && lm[0] > lm[2] && lm[0] > (255-(lm[0]+lm[1]+lm[2])))
	{
		lm[0] = lm[0]*(1-w) + 255*(w);
		lm[1] = lm[1]*(1-w) + 0*(w);
		lm[2] = lm[2]*(1-w) + 0*(w);
	}
	else if (lm[1] > lm[2] && lm[1] > (255-(lm[0]+lm[1]+lm[2])))
	{
		lm[0] = lm[0]*(1-w) + 0*(w);
		lm[1] = lm[1]*(1-w) + 255*(w);
		lm[2] = lm[2]*(1-w) + 0*(w);
	}
	else if (lm[2] > (255-(lm[0]+lm[1]+lm[2])))
	{
		lm[0] = lm[0]*(1-w) + 0*(w);
		lm[1] = lm[1]*(1-w) + 0*(w);
		lm[2] = lm[2]*(1-w) + 255*(w);
	}
	else
	{
		lm[0] = lm[0]*(1-w) + 0*(w);
		lm[1] = lm[1]*(1-w) + 0*(w);
		lm[2] = lm[2]*(1-w) + 0*(w);
	}
}

static void ted_mixnoise(void *ctx, hmsection_t *s, int idx, float wx, float wy, float w)
{
	unsigned char *lm = ted_getlightmap(s, idx);
	vec4_t v;
	float sc;

	s->flags |= TSF_NOTIFY|TSF_EDITED;

	/*randomize the lightmap somewhat (you'll probably want to concentrate it a bit after)*/
	v[0] = (rand()&255);
	v[1] = (rand()&255);
	v[2] = (rand()&255);
	v[3] = (rand()&255);
	sc = v[0] + v[1] + v[2] + v[3];
	Vector4Scale(v, 255/sc, v);

	lm[0] = lm[0]*(1-w) + (v[0]*(w));
	lm[1] = lm[1]*(1-w) + (v[1]*(w));
	lm[2] = lm[2]*(1-w) + (v[2]*(w));
}

static void ted_mixpaint(void *ctx, hmsection_t *s, int idx, float wx, float wy, float w)
{
	unsigned char *lm = ted_getlightmap(s, idx);
	const char *texname = ctx;
	int t;
	vec3_t newval;
	if (w > 1)
		w = 1;

	s->flags |= TSF_NOTIFY|TSF_EDITED;

	for (t = 0; t < 4; t++)
	{
		if (!strncmp(s->texname[t], texname, sizeof(s->texname[t])-1))
		{
			newval[0] = (t == 0);
			newval[1] = (t == 1);
			newval[2] = (t == 2);
			lm[2] = lm[2]*(1-w) + (255*newval[0]*(w));
			lm[1] = lm[1]*(1-w) + (255*newval[1]*(w));
			lm[0] = lm[0]*(1-w) + (255*newval[2]*(w));
			return;
		}
	}

	/*special handling to make a section accept the first texture painted on it as a base texture. no more chessboard*/
	if (!*s->texname[0] && !*s->texname[1] && !*s->texname[2] && !*s->texname[3])
	{
		Q_strncpyz(s->texname[3], texname, sizeof(s->texname[3]));
		Terr_LoadSectionTextures(s);

		for (idx = 0; idx < SECTTEXSIZE*SECTTEXSIZE; idx++)
		{
			lm = ted_getlightmap(s, idx);
			lm[2] = 0;
			lm[1] = 0;
			lm[0] = 0;
		}
		return;
	}
	for (t = 0; t < 4; t++)
	{
		if (!*s->texname[t])
		{
			Q_strncpyz(s->texname[t], texname, sizeof(s->texname[t]));

			newval[0] = (t == 0);
			newval[1] = (t == 1);
			newval[2] = (t == 2);
			lm[2] = lm[2]*(1-w) + (255*newval[0]*(w));
			lm[1] = lm[1]*(1-w) + (255*newval[1]*(w));
			lm[0] = lm[0]*(1-w) + (255*newval[2]*(w));

			Terr_LoadSectionTextures(s);
			return;
		}
	}
}

/*
static void ted_mixlight(void *ctx, hmsection_t *s, int idx, float wx, float wy, float w)
{
	unsigned char *lm = ted_getlightmap(s, idx);
	vec3_t pos, pos2;
	vec3_t norm, tnorm;
	vec3_t ldir = {0.4, 0.7, 2};
	float d;
	int x,y;
	trace_t tr;
	VectorClear(norm);
	for (y = -4; y < 4; y++)
	for (x = -4; x < 4; x++)
	{
		pos[0] = wx - (CHUNKBIAS + x/64.0) * s->hmmod->sectionsize;
		pos[1] = wy - (CHUNKBIAS + y/64.0) * s->hmmod->sectionsize;
#if 0
		pos[2] = 10000;
		pos2[0] = wx - (CHUNKBIAS + x/64.0) * s->hmmod->sectionsize;
		pos2[1] = wy - (CHUNKBIAS + y/64.0) * s->hmmod->sectionsize;
		pos2[2] = -10000;
		Heightmap_Trace(cl.worldmodel, 0, 0, NULL, pos, pos2, vec3_origin, vec3_origin, FTECONTENTS_SOLID, &tr);
		VectorCopy(tr.plane.normal, tnorm);
#else
		Heightmap_Normal(s->hmmod, pos, tnorm);
#endif
		d = sqrt(32 - x*x+y*y);
		VectorMA(norm, d, tnorm, norm);
	}

	VectorNormalize(ldir);
	VectorNormalize(norm);
	d = DotProduct(ldir, norm);
	if (d < 0)
		d = 0;
	lm[3] = d*255;
}
*/
static void ted_mixset(void *ctx, hmsection_t *s, int idx, float wx, float wy, float w)
{
	unsigned char *lm = ted_getlightmap(s, idx);
	if (w > 1)
		w = 1;
	s->flags |= TSF_NOTIFY|TSF_EDITED;

	lm[2] = lm[2]*(1-w) + (255*((float*)ctx)[0]*(w));
	lm[1] = lm[1]*(1-w) + (255*((float*)ctx)[1]*(w));
	lm[0] = lm[0]*(1-w) + (255*((float*)ctx)[2]*(w));
}

static void ted_mixtally(void *ctx, hmsection_t *s, int idx, float wx, float wy, float w)
{
	unsigned char *lm = ted_getlightmap(s, idx);
	((float*)ctx)[0] += lm[0]*w;
	((float*)ctx)[1] += lm[1]*w;
	((float*)ctx)[2] += lm[2]*w;
	((float*)ctx)[3] += w;
}

static void ted_tint(void *ctx, hmsection_t *s, int idx, float wx, float wy, float w)
{
	float *col = s->colours[idx];
	float *newval = ctx;
	if (w > 1)
		w = 1;
	s->flags |= TSF_NOTIFY|TSF_DIRTY|TSF_EDITED|TSF_HASCOLOURS;	/*dirty because of the vbo*/
	col[0] = col[0]*(1-w) + (newval[0]*(w));
	col[1] = col[1]*(1-w) + (newval[1]*(w));
	col[2] = col[2]*(1-w) + (newval[2]*(w));
	col[3] = col[3]*(1-w) + (newval[3]*(w));
}

enum
{
	tid_linear,
	tid_exponential
};
//calls 'func' for each tile upon the terrain. the 'tile' can be either height or texel
static void ted_itterate(heightmap_t *hm, int distribution, float *pos, float radius, float strength, int steps, void(*func)(void *ctx, hmsection_t *s, int idx, float wx, float wy, float strength), void *ctx)
{
	int tx, ty;
	float wx, wy;
	float sc[2];
	int min[2], max[2];
	int sx,sy;
	hmsection_t *s;
	float w, xd, yd;

	min[0] = floor((pos[0] - radius)/(hm->sectionsize) - 1.5);
	min[1] = floor((pos[1] - radius)/(hm->sectionsize) - 1.5);
	max[0] = ceil((pos[0] + radius)/(hm->sectionsize) + 1.5);
	max[1] = ceil((pos[1] + radius)/(hm->sectionsize) + 1.5);

	min[0] = bound(hm->firstsegx, min[0], hm->maxsegx);
	min[1] = bound(hm->firstsegy, min[1], hm->maxsegy);
	max[0] = bound(hm->firstsegx, max[0], hm->maxsegx);
	max[1] = bound(hm->firstsegy, max[1], hm->maxsegy);

	sc[0] = hm->sectionsize/(steps-1);
	sc[1] = hm->sectionsize/(steps-1);

	for (sy = min[1]; sy < max[1]; sy++)
	{
		for (sx = min[0]; sx < max[0]; sx++)
		{
			s = Terr_GetSection(hm, sx, sy, TGS_FORCELOAD);
			if (!s)
				continue;

			for (ty = 0; ty < steps; ty++)
			{
				wy = (sy*(steps-1.0) + ty)*sc[1];
				yd = wy - pos[1];// - sc[1]/4;
//				if (yd < 0)
//					yd = 0;
				for (tx = 0; tx < steps; tx++)
				{
					/*both heights and textures have an overlapping/matching sample at the edge, there's no need for any half-pixels or anything here*/
					wx = (sx*(steps-1.0) + tx)*sc[0];
					xd = wx - pos[0];// - sc[0]/4;
//					if (xd < 0)
//						xd = 0;

					if (radius*radius >= (xd*xd+yd*yd))
					{
						if (distribution == tid_exponential)
							w = sqrt((radius*radius) - ((xd*xd)+(yd*yd)));
						else
							w = radius - sqrt(xd*xd+yd*yd);
						if (w > 0)
							func(ctx, s, tx+ty*steps, wx, wy, w*strength/(radius));
					}
				}
			}
		}
	}
}

void ted_texkill(hmsection_t *s, const char *killtex)
{
	int x, y, t, to;
	if (!s)
		return;
	for (t = 0; t < 4; t++)
	{
		if (!strcmp(s->texname[t], killtex))
		{
			unsigned char *lm = ted_getlightmap(s, 0);
			s->flags |= TSF_EDITED;
			s->texname[t][0] = 0;
			for (to = 0; to < 4; to++)
				if (*s->texname[to])
					break;
			if (to == 4)
				to = 0;

			if (to == 0 || to == 2)
				to = 2 - to;
			if (t == 0 || t == 2)
				t = 2 - t;

			for (y = 0; y < SECTTEXSIZE; y++)
			{
				for (x = 0; x < SECTTEXSIZE; x++, lm+=4)
				{
					if (t == 3)
					{
						//to won't be 3
						lm[to] = lm[to] + (255 - (lm[0] + lm[1] + lm[2]));
					}
					else
					{
						if (to != 3)
							lm[to] += lm[t];
						lm[t] = 0;
					}
				}
				lm += SECTTEXSIZE*4*(LMCHUNKS-1);
			}
			if (t == 0 || t == 2)
				t = 2 - t;
			Terr_LoadSectionTextures(s);
		}
	}
}

void QCBUILTIN PF_terrain_edit(pubprogfuncs_t *prinst, struct globalvars_s *pr_globals)
{
	world_t *vmw = prinst->parms->user;
	int action = G_FLOAT(OFS_PARM0);
	vec3_t pos;// G_VECTOR(OFS_PARM1);
	float radius = G_FLOAT(OFS_PARM2);
	float quant = G_FLOAT(OFS_PARM3);
//	G_FLOAT(OFS_RETURN) = Heightmap_Edit(w->worldmodel, action, pos, radius, quant);
	model_t *mod = vmw->Get_CModel(vmw, ((wedict_t*)PROG_TO_EDICT(prinst, *vmw->g.self))->v->modelindex);
	heightmap_t *hm;
	vec4_t tally;

	G_FLOAT(OFS_RETURN) = 0;

	if (!mod || !mod->terrain)
	{
		if (mod)
		{
			char basename[MAX_QPATH];
			COM_FileBase(mod->name, basename, sizeof(basename));
			mod->terrain = Mod_LoadTerrainInfo(mod, basename, true);
			G_FLOAT(OFS_RETURN) = !!mod->terrain;
		}
		return;
	}
	hm = mod->terrain;

	pos[0] = G_FLOAT(OFS_PARM1+0) + hm->sectionsize * CHUNKBIAS;
	pos[1] = G_FLOAT(OFS_PARM1+1) + hm->sectionsize * CHUNKBIAS;
	pos[2] = G_FLOAT(OFS_PARM1+2);

	switch(action)
	{
	case ter_reload:
		G_FLOAT(OFS_RETURN) = 1;
		Terr_PurgeTerrainModel(mod, false, true);
		break;
	case ter_save:
		quant = Heightmap_Save(hm);
		Con_DPrintf("ter_save: %g sections saved\n", quant);
		G_FLOAT(OFS_RETURN) = quant;
		break;
	case ter_sethole:
	/*	{
			int x, y;
			hmsection_t *s;
			x = pos[0]*4 / hm->sectionsize;
			y = pos[1]*4 / hm->sectionsize;
			x = bound(hm->firstsegx*4, x, hm->maxsegy*4-1);
			y = bound(hm->firstsegy*4, y, hm->maxsegy*4-1);
		
			s = Terr_GetSection(hm, x/4, y/4, TGS_FORCELOAD);
			if (!s)
				return;
			ted_sethole(&quant, s, (x&3) + (y&3)*4, x/4, y/4, 0);
		}
	*/	
		pos[0] -= 0.5 * hm->sectionsize / 8;
		pos[1] -= 0.5 * hm->sectionsize / 8;
		ted_itterate(hm, tid_linear, pos, radius, 1, 9, ted_sethole, &quant);
		break;
	case ter_height_set:
		ted_itterate(hm, tid_linear, pos, radius, 1, SECTHEIGHTSIZE, ted_heightset, &quant);
		break;
	case ter_height_flatten:
		tally[0] = 0;
		tally[1] = 0;
		ted_itterate(hm, tid_exponential, pos, radius, 1, SECTHEIGHTSIZE, ted_heighttally, &tally);
		tally[0] /= tally[1];
		if (IS_NAN(tally[0]))
			tally[0] = 0;
		ted_itterate(hm, tid_exponential, pos, radius, quant, SECTHEIGHTSIZE, ted_heightsmooth, &tally);
		break;
	case ter_height_smooth:
		tally[0] = 0;
		tally[1] = 0;
		ted_itterate(hm, tid_linear, pos, radius, 1, SECTHEIGHTSIZE, ted_heighttally, &tally);
		tally[0] /= tally[1];
		if (IS_NAN(tally[0]))
			tally[0] = 0;
		ted_itterate(hm, tid_linear, pos, radius, quant, SECTHEIGHTSIZE, ted_heightsmooth, &tally);
		break;
	case ter_height_spread:
		tally[0] = 0;
		tally[1] = 0;
		ted_itterate(hm, tid_exponential, pos, radius/2, 1, SECTHEIGHTSIZE, ted_heighttally, &tally);
		tally[0] /= tally[1];
		if (IS_NAN(tally[0]))
			tally[0] = 0;
		ted_itterate(hm, tid_exponential, pos, radius, 1, SECTHEIGHTSIZE, ted_heightsmooth, &tally);
		break;
	case ter_water_set:
		ted_itterate(hm, tid_linear, pos, radius, 1, 9, ted_waterset, &quant);
		break;
	case ter_lower:
		quant *= -1;
	case ter_raise:
		ted_itterate(hm, tid_exponential, pos, radius, quant, SECTHEIGHTSIZE, ted_heightraise, &quant);
		break;
	case ter_tint:
		ted_itterate(hm, tid_exponential, pos, radius, quant, SECTHEIGHTSIZE, ted_tint, G_VECTOR(OFS_PARM4));	//and parm5 too
		break;
//	case ter_mixset:
//		ted_itterate(hm, tid_exponential, pos, radius, 1, SECTTEXSIZE, ted_mixset, G_VECTOR(OFS_PARM4));
//		break;
	case ter_mix_paint:
		ted_itterate(hm, tid_exponential, pos, radius, quant/10, SECTTEXSIZE, ted_mixpaint, (void*)PR_GetStringOfs(prinst, OFS_PARM4));
		break;
	case ter_mix_concentrate:
		ted_itterate(hm, tid_exponential, pos, radius, 1, SECTTEXSIZE, ted_mixconcentrate, NULL);
		break;
	case ter_mix_noise:
		ted_itterate(hm, tid_exponential, pos, radius, 1, SECTTEXSIZE, ted_mixnoise, NULL);
		break;
	case ter_mix_blur:
		Vector4Set(tally, 0, 0, 0, 0);
		ted_itterate(hm, tid_exponential, pos, radius, 1, SECTTEXSIZE, ted_mixtally, &tally);
		VectorScale(tally, 1/(tally[3]*255), tally);
		ted_itterate(hm, tid_exponential, pos, radius, quant, SECTTEXSIZE, ted_mixset, &tally);
		break;
	case ter_tex_get:
		{
			int x, y;
			hmsection_t *s;
			x = pos[0] / hm->sectionsize;
			y = pos[1] / hm->sectionsize;
			x = bound(hm->firstsegx, x, hm->maxsegy-1);
			y = bound(hm->firstsegy, y, hm->maxsegy-1);
		
			s = Terr_GetSection(hm, x, y, TGS_LOAD);
			if (!s)
				return;
			x = bound(0, quant, 3);
			G_INT(OFS_RETURN) = PR_TempString(prinst, s->texname[x]);
		}
		break;
	case ter_tex_kill:
		{
			int x, y;
			x = pos[0] / hm->sectionsize;
			y = pos[1] / hm->sectionsize;
			x = bound(hm->firstsegx, x, hm->maxsegy-1);
			y = bound(hm->firstsegy, y, hm->maxsegy-1);

			ted_texkill(Terr_GetSection(hm, x, y, TGS_FORCELOAD), PR_GetStringOfs(prinst, OFS_PARM4));
		}
		break;
	case ter_mesh_add:
		{
			entity_t *e;
			float *epos;
			int x, y;
			hmsection_t *s;
			epos = ((wedict_t *)G_EDICT(prinst, OFS_PARM1))->v->origin;
			x = (epos[0] / hm->sectionsize) + CHUNKBIAS;
			y = (epos[1] / hm->sectionsize) + CHUNKBIAS;
			x = bound(hm->firstsegx, x, hm->maxsegy-1);
			y = bound(hm->firstsegy, y, hm->maxsegy-1);
		
			s = Terr_GetSection(hm, x, y, TGS_FORCELOAD);
			if (!s)
				return;

			s->flags |= TSF_EDITED;

			if (s->maxents == s->numents)
			{
				s->maxents++;
				s->ents = realloc(s->ents, sizeof(*s->ents)*(s->maxents));
			}
			e = &s->ents[s->numents++];

			memset(e, 0, sizeof(*e));
			e->scale = ((wedict_t *)G_EDICT(prinst, OFS_PARM1))->xv->scale;
			e->playerindex = -1;
			e->shaderRGBAf[0] = 1;
			e->shaderRGBAf[1] = 1;
			e->shaderRGBAf[2] = 1;
			e->shaderRGBAf[3] = 1;
			VectorCopy(epos, e->origin);
			AngleVectorsFLU(((wedict_t *)G_EDICT(prinst, OFS_PARM1))->v->angles, e->axis[0], e->axis[1], e->axis[2]);
			e->model = vmw->Get_CModel(vmw, ((wedict_t *)G_EDICT(prinst, OFS_PARM1))->v->modelindex);
		}
		break;
	case ter_mesh_kill:
		{
//			int i;
//			entity_t *e;
			int x, y;
//			float r;
			hmsection_t *s;
			x = pos[0] / hm->sectionsize;
			y = pos[1] / hm->sectionsize;
			x = bound(hm->firstsegx, x, hm->maxsegy-1);
			y = bound(hm->firstsegy, y, hm->maxsegy-1);
		
			s = Terr_GetSection(hm, x, y, TGS_FORCELOAD);
			if (!s)
				return;

			s->numents = 0;
			s->flags |= TSF_EDITED;

			/*for (i = 0; i < s->numents; i++)
			{

			}*/
		}
		break;
	}
}
#else
void QCBUILTIN PF_terrain_edit(pubprogfuncs_t *prinst, struct globalvars_s *pr_globals)
{
	G_FLOAT(OFS_RETURN) = 0;
}
#endif

void Terr_ParseEntityLump(char *data, heightmap_t *heightmap)
{
	char key[128];

	heightmap->sectionsize = 1024;
	heightmap->mode = HMM_TERRAIN;

	if (data)
	if ((data=COM_Parse(data)))	//read the map info.
	if (com_token[0] == '{')
	while (1)
	{
		if (!(data=COM_Parse(data)))
			break; // error
		if (com_token[0] == '}')
			break; // end of worldspawn
		if (com_token[0] == '_')
			strcpy(key, com_token + 1);	//_ vars are for comments/utility stuff that arn't visible to progs. Ignore them.
		else
			strcpy(key, com_token);
		if (!((data=COM_Parse(data))))
			break; // error		
		if (!strcmp("segmentsize", key))
			heightmap->sectionsize = atof(com_token);
		else if (!strcmp("minxsegment", key))
			heightmap->firstsegx = atoi(com_token);
		else if (!strcmp("minysegment", key))
			heightmap->firstsegy = atoi(com_token);
		else if (!strcmp("maxxsegment", key))
			heightmap->maxsegx = atoi(com_token);
		else if (!strcmp("maxysegment", key))
			heightmap->maxsegy = atoi(com_token);
		else if (!strcmp("tiles", key))
		{
			char *d;
			heightmap->mode = HMM_BLOCKS;
			d = com_token;
			d = COM_ParseOut(d, key, sizeof(key));
			heightmap->tilepixcount[0] = atoi(key);
			d = COM_ParseOut(d, key, sizeof(key));
			heightmap->tilepixcount[1] = atoi(key);
			d = COM_ParseOut(d, key, sizeof(key));
			heightmap->tilecount[0] = atoi(key);
			d = COM_ParseOut(d, key, sizeof(key));
			heightmap->tilecount[1] = atoi(key);
		}
	}

	/*bias and bound it*/
	heightmap->firstsegx += CHUNKBIAS;
	heightmap->firstsegy += CHUNKBIAS;
	heightmap->maxsegx += CHUNKBIAS;
	heightmap->maxsegy += CHUNKBIAS;
	if (heightmap->firstsegx < 0)
		heightmap->firstsegx = 0;
	if (heightmap->firstsegy < 0)
		heightmap->firstsegy = 0;
	if (heightmap->maxsegx > CHUNKLIMIT)
		heightmap->maxsegx = CHUNKLIMIT;
	if (heightmap->maxsegy > CHUNKLIMIT)
		heightmap->maxsegy = CHUNKLIMIT;
}

void Terr_FinishTerrain(heightmap_t *hm, char *shadername, char *skyname)
{
#ifndef SERVERONLY
	if (qrenderer != QR_NONE)
	{
		Q_strncpyz(hm->watershadername, va("water/%s", hm->path), sizeof(hm->watershadername));
		if (skyname)
			hm->skyshader = R_RegisterCustom(va("skybox_%s", skyname), SUF_NONE, Shader_DefaultSkybox, NULL);
		else
			hm->skyshader = NULL;

		switch (hm->mode)
		{
		case HMM_BLOCKS:
			hm->shader = R_RegisterShader("terraintileshader", SUF_NONE,
					"{\n"
						"{\n"
							"map $diffuse\n"	
						"}\n"
					"}\n"
				);
			break;
		case HMM_TERRAIN:
			hm->shader = R_RegisterShader(shadername, SUF_LIGHTMAP,
					"{\n"
						"bemode rtlight\n"
							"{\n"
								"{\n"
									"map $diffuse\n"
									"blendfunc add\n"
								"}\n"
								"{\n"
									"map $upperoverlay\n"
								"}\n"
								"{\n"
									"map $loweroverlay\n"
								"}\n"
								"{\n"
									"map $fullbright\n"
								"}\n"
								"{\n"
									"map $lightmap\n"
								"}\n"
								"{\n"
									"map $shadowmap\n"
								"}\n"
								"{\n"
									"map $lightcubemap\n"
								"}\n"
								//woo, one glsl to rule them all
								"program terrain#RTLIGHT\n"
							"}\n"
						"bemode depthdark\n"
							"{\n"
								"program depthonly\n"
								"{\n"
									"depthwrite\n"
								"}\n"
							"}\n"
						"bemode depthonly\n"
							"{\n"
								"program depthonly\n"
								"{\n"
									"depthwrite\n"
									"colormask\n"
								"}\n"
							"}\n"

						"{\n"
							"map $diffuse\n"
						"}\n"
						"{\n"
							"map $upperoverlay\n"
						"}\n"
						"{\n"
							"map $loweroverlay\n"
						"}\n"
						"{\n"
							"map $fullbright\n"
						"}\n"
						"{\n"
							"map $lightmap\n"
						"}\n"
						"program terrain\n"
						"if r_terraindebug\n"
						"program terraindebug\n"
						"endif\n"
					"}\n"
				);
			break;
		}
	}
#endif
}

qboolean QDECL Terr_LoadTerrainModel (model_t *mod, void *buffer, size_t bufsize)
{
	heightmap_t *hm;

	char shadername[MAX_QPATH];
	char skyname[MAX_QPATH];
	int sectsize = 0;

	COM_FileBase(mod->name, shadername, sizeof(shadername));
	strcpy(shadername, "terrainshader");
	strcpy(skyname, "sky1");

	buffer = COM_Parse(buffer);
	if (strcmp(com_token, "terrain"))
	{
		Con_Printf(CON_ERROR "%s wasn't terrain map\n", mod->name);	//shouldn't happen
		return false;
	}

	mod->type = mod_heightmap;

	hm = Z_Malloc(sizeof(*hm));
	ClearLink(&hm->recycle);
//	ClearLink(&hm->collected);
	COM_FileBase(mod->name, hm->path, sizeof(hm->path));

	mod->entities = ZG_Malloc(&mod->memgroup, strlen(buffer)+1);
	strcpy(mod->entities, buffer);

	hm->sectionsize = sectsize;
	hm->firstsegx = -1;
	hm->firstsegy = -1;
	hm->maxsegx = +1;
	hm->maxsegy = +1;
	hm->exteriorcontents = FTECONTENTS_SOLID;	//sky outside the map

	Terr_ParseEntityLump(mod->entities, hm);

	mod->mins[0] = (hm->firstsegx - CHUNKBIAS) * hm->sectionsize;
	mod->mins[1] = (hm->firstsegy - CHUNKBIAS) * hm->sectionsize;
	mod->mins[2] = -999999999999999999999999.f;
	mod->maxs[0] = (hm->maxsegy - CHUNKBIAS) * hm->sectionsize;
	mod->maxs[1] = (hm->maxsegy - CHUNKBIAS) * hm->sectionsize;
	mod->maxs[2] = 999999999999999999999999.f;

	mod->funcs.NativeTrace			= Heightmap_Trace;
	mod->funcs.PointContents		= Heightmap_PointContents;

	mod->funcs.NativeContents		= Heightmap_NativeBoxContents;

	mod->funcs.LightPointValues		= Heightmap_LightPointValues;
	mod->funcs.StainNode			= Heightmap_StainNode;
	mod->funcs.MarkLights			= Heightmap_MarkLights;

	mod->funcs.LeafnumForPoint		= Heightmap_LeafForPoint;
	mod->funcs.LeafPVS				= Heightmap_LeafnumPVS;

#ifndef CLIENTONLY
	mod->funcs.FindTouchedLeafs		= Heightmap_FindTouchedLeafs;
	mod->funcs.EdictInFatPVS		= Heightmap_EdictInFatPVS;
	mod->funcs.FatPVS				= Heightmap_FatPVS;
#endif
/*	mod->hulls[0].funcs.HullPointContents = Heightmap_PointContents;
	mod->hulls[1].funcs.HullPointContents = Heightmap_PointContents;
	mod->hulls[2].funcs.HullPointContents = Heightmap_PointContents;
	mod->hulls[3].funcs.HullPointContents = Heightmap_PointContents;
*/

	mod->terrain = hm;

	Terr_FinishTerrain(hm, shadername, skyname);

	return true;
}

void *Mod_LoadTerrainInfo(model_t *mod, char *loadname, qboolean force)
{
	heightmap_t *hm;
	heightmap_t potential;
	if (!mod->entities)
		return NULL;

	memset(&potential, 0, sizeof(potential));
	Terr_ParseEntityLump(mod->entities, &potential);

	if (potential.firstsegx >= potential.maxsegx || potential.firstsegy >= potential.maxsegy)
	{
		//figure out the size such that it encompases the entire bsp.
		potential.firstsegx = floor(mod->mins[0] / potential.sectionsize) + CHUNKBIAS;
		potential.firstsegy = floor(mod->mins[1] / potential.sectionsize) + CHUNKBIAS;
		potential.maxsegx = ceil(mod->maxs[0] / potential.sectionsize) + CHUNKBIAS;
		potential.maxsegy = ceil(mod->maxs[1] / potential.sectionsize) + CHUNKBIAS;
		//bound it, such that 0 0 will always be loaded.
		potential.firstsegx = bound(0, potential.firstsegx, CHUNKBIAS);
		potential.firstsegy = bound(0, potential.firstsegy, CHUNKBIAS);
		potential.maxsegx = bound(CHUNKBIAS+1, potential.maxsegx, CHUNKLIMIT);
		potential.maxsegy = bound(CHUNKBIAS+1, potential.maxsegy, CHUNKLIMIT);

		if (!force)
			if (!COM_FCheckExists(va("maps/%s/sect_%03x_%03x.hms", loadname, potential.firstsegx + (potential.maxsegx-potential.firstsegx)/2, potential.firstsegy + (potential.maxsegy-potential.firstsegy)/2)))
				if (!COM_FCheckExists(va("maps/%s/block_00_00.hms", loadname)))
					return NULL;
	}

	hm = Z_Malloc(sizeof(*hm));
	*hm = potential;
	ClearLink(&hm->recycle);
	Q_strncpyz(hm->path, loadname, sizeof(hm->path));

	hm->exteriorcontents = FTECONTENTS_EMPTY;	//bsp geometry outside the heightmap

	Terr_FinishTerrain(hm, "terrainshader", NULL);

	return hm;
}

void Mod_Terrain_Create_f(void)
{
	char *mname;
	char *mdata;
	mname = va("maps/%s.hmp", Cmd_Argv(1));
	mdata = va(
		"terrain\n"
		"{\n"
			"classname \"worldspawn\"\n"
			"message \"%s\"\n"
			"_sky sky1\n"
			"_fog 0.02\n"
			"_segmentsize 1024\n"
			"_minxsegment -2048\n"
			"_minysegment -2048\n"
			"_maxxsegment 2048\n"
			"_maxysegment 2048\n"
//			"_tiles 64 64 8 8\n"
		"}\n"
		"{\n"
			"classname info_player_start\n"
			"origin \"0 0 1024\"\n"
		"}\n"
		, Cmd_Argv(2));
	COM_WriteFile(mname, mdata, strlen(mdata));
}
//reads in the terrain a tile at a time, and writes it out again.
//the new version will match our current format version.
//this is mostly so I can strip out old format revisions...
#ifndef SERVERONLY
void Mod_Terrain_Convert_f(void)
{
	model_t *mod;
	heightmap_t *hm;
	if (Cmd_FromGamecode())
		return;

	if (Cmd_Argc() >= 2)
		mod = Mod_FindName(va("maps/%s.hmp", Cmd_Argv(1)));
	else if (cls.state)
		mod = cl.worldmodel;
	else
		mod = NULL;
	if (!mod || mod->type == mod_dummy)
		return;
	hm = mod->terrain;
	if (!hm)
		return;

	{
		char *texkill = Cmd_Argv(2);
		hmsection_t *s;
		int x, sx;
		int y, sy;

		while(Terr_Collect(hm))	//collect as many as we can now, so when we collect later, the one that's collected is fresh.
			;
		for (y = hm->firstsegy; y < hm->maxsegy; y+=SECTIONSPERBLOCK)
		{
			Sys_Printf("%g%% complete\n", 100 * (y-hm->firstsegy)/(float)(hm->maxsegy-hm->firstsegy));
			for (x = hm->firstsegx; x < hm->maxsegx; x+=SECTIONSPERBLOCK)
			{
				for (sy = y; sy < y+SECTIONSPERBLOCK && sy < hm->maxsegy; sy++)
				{
					for (sx = x; sx < x+SECTIONSPERBLOCK && sx < hm->maxsegx; sx++)
					{
						s = Terr_GetSection(hm, sx, sy, TGS_LOAD|TGS_NODOWNLOAD|TGS_NORENDER);
						if (s)
						{
							if (*texkill)
								ted_texkill(s, texkill);
							s->flags |= TSF_EDITED;
						}
					}
				}
				for (sy = y; sy < y+SECTIONSPERBLOCK && sy < hm->maxsegy; sy++)
				{
					for (sx = x; sx < x+SECTIONSPERBLOCK && sx < hm->maxsegx; sx++)
					{
						s = Terr_GetSection(hm, sx, sy, TGS_LOAD|TGS_NODOWNLOAD|TGS_NORENDER);
						if (s)
						{
							if (s->flags & TSF_EDITED)
							{
								if (Terr_SaveSection(hm, s, sx, sy, true))
								{
									s->flags &= ~TSF_EDITED;
								}
							}
						}
					}
				}
				while(Terr_Collect(hm))
					;
			}
		}
		Sys_Printf("%g%% complete\n", 100.0f);
	}
}
#endif
void Mod_Terrain_Reload_f(void)
{
	model_t *mod;
	heightmap_t *hm;
	if (Cmd_Argc() >= 2)
		mod = Mod_FindName(va("maps/%s.hmp", Cmd_Argv(1)));
#ifndef SERVERONLY
	else if (cls.state)
		mod = cl.worldmodel;
#endif
	else
		mod = NULL;
	if (!mod || mod->type == mod_dummy)
		return;
	hm = mod->terrain;
	if (!hm)
		return;

	if (Cmd_Argc() >= 4)
	{
		hmsection_t *s;
		int sx = atoi(Cmd_Argv(2)) + CHUNKBIAS;
		int sy = atoi(Cmd_Argv(3)) + CHUNKBIAS;
		if (hm)
		{
			s = Terr_GetSection(hm, sx, sy, TGS_NOLOAD);
			if (s)
			{
				s->flags |= TSF_NOTIFY;
			}
		}
	}
	else
		Terr_PurgeTerrainModel(mod, false, true);
}

void Terr_Init(void)
{
	Cvar_Register(&mod_terrain_networked, "Terrain");
	Cvar_Register(&mod_terrain_defaulttexture, "Terrain");
	Cvar_Register(&mod_terrain_savever, "Terrain");
	Cmd_AddCommand("mod_terrain_create", Mod_Terrain_Create_f);
	Cmd_AddCommand("mod_terrain_reload", Mod_Terrain_Reload_f);
#ifndef SERVERONLY
	Cmd_AddCommandD("mod_terrain_convert", Mod_Terrain_Convert_f, "mod_terrain_convert [mapname] [texkill]\nConvert a terrain to the current format. If texkill is specified, only tiles with the named texture will be converted, and tiles with that texture will be stripped. This is a slow operation.");
#endif

	Mod_RegisterModelFormatText(NULL, "FTE Heightmap Map (hmp)", "terrain", Terr_LoadTerrainModel);
}
#endif