/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.

This file is part of Quake III Arena source code.

Quake III Arena source code is free software; you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.

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

You should have received a copy of the GNU General Public License
along with Quake III Arena source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/
// tr_models.c -- model loading and caching

#include "tr_local.h"

#define	LL(x) x=LittleLong(x)

static qboolean R_LoadMD3 (model_t *mod, int lod, void *buffer, const char *name );
static qboolean R_LoadMD4 (model_t *mod, void *buffer, const char *name );
#ifdef RAVENMD4
static qboolean R_LoadMDR (model_t *mod, void *buffer, int filesize, const char *name );
#endif

model_t	*loadmodel;

/*
** R_GetModelByHandle
*/
model_t	*R_GetModelByHandle( qhandle_t index ) {
	model_t		*mod;

	// out of range gets the defualt model
	if ( index < 1 || index >= tr.numModels ) {
		return tr.models[0];
	}

	mod = tr.models[index];

	return mod;
}

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

/*
** R_AllocModel
*/
model_t *R_AllocModel( void ) {
	model_t		*mod;

	if ( tr.numModels == MAX_MOD_KNOWN ) {
		return NULL;
	}

	mod = ri.Hunk_Alloc( sizeof( *tr.models[tr.numModels] ), h_low );
	mod->index = tr.numModels;
	tr.models[tr.numModels] = mod;
	tr.numModels++;

	return mod;
}

/*
====================
RE_RegisterModel

Loads in a model for the given name

Zero will be returned if the model fails to load.
An entry will be retained for failed models as an
optimization to prevent disk rescanning if they are
asked for again.
====================
*/
qhandle_t RE_RegisterModel( const char *name ) {
	model_t		*mod;
	union {
		unsigned *u;
		void *v;
	} buf;
	int			lod;
	int			ident;
	qboolean	loaded = qfalse;
	qhandle_t	hModel;
	int			numLoaded;
	char		*fext, defex[] = "md3", filename[MAX_QPATH], namebuf[MAX_QPATH+20];

	if ( !name || !name[0] ) {
		ri.Printf( PRINT_ALL, "RE_RegisterModel: NULL name\n" );
		return 0;
	}

	if ( strlen( name ) >= MAX_QPATH ) {
		Com_Printf( "Model name exceeds MAX_QPATH\n" );
		return 0;
	}

	//
	// search the currently loaded models
	//
	for ( hModel = 1 ; hModel < tr.numModels; hModel++ ) {
		mod = tr.models[hModel];
		if ( !strcmp( mod->name, name ) ) {
			if( mod->type == MOD_BAD ) {
				return 0;
			}
			return hModel;
		}
	}

	// allocate a new model_t

	if ( ( mod = R_AllocModel() ) == NULL ) {
		ri.Printf( PRINT_WARNING, "RE_RegisterModel: R_AllocModel() failed for '%s'\n", name);
		return 0;
	}

	// only set the name after the model has been successfully loaded
	Q_strncpyz( mod->name, name, sizeof( mod->name ) );


	// make sure the render thread is stopped
	R_SyncRenderThread();

	mod->numLods = 0;

	//
	// load the files
	//
	numLoaded = 0;

	strcpy(filename, name);

	fext = strchr(filename, '.');
	if(!fext)
		fext = defex;
	else
	{
		*fext = '\0';
		fext++;
	}

#ifdef RAVENMD4
	if(!Q_stricmp(fext, "mdr"))
	{
		int filesize;
		
		filesize = ri.FS_ReadFile(name, (void **) &buf.v);
		if(!buf.u)
		{
			ri.Printf (PRINT_WARNING,"RE_RegisterModel: couldn't load %s\n", name);
			mod->type = MOD_BAD;
			return 0;
		}
		
		ident = LittleLong(*(unsigned *)buf.u);
		if(ident == MDR_IDENT)
			loaded = R_LoadMDR(mod, buf.u, filesize, name);

		ri.FS_FreeFile (buf.v);
		
		if(!loaded)
		{
			ri.Printf(PRINT_WARNING,"RE_RegisterModel: couldn't load mdr file %s\n", name);
			mod->type = MOD_BAD;
			return 0;
		}
		
		return mod->index;
	}
#endif

	fext = defex;

	for ( lod = MD3_MAX_LODS - 1 ; lod >= 0 ; lod-- ) {
		if ( lod )
			Com_sprintf(namebuf, sizeof(namebuf), "%s_%d.%s", filename, lod, fext);
		else
			Com_sprintf(namebuf, sizeof(namebuf), "%s.%s", filename, fext);

		ri.FS_ReadFile( namebuf, &buf.v );
		if ( !buf.u ) {
			continue;
		}
		
		loadmodel = mod;
		
		ident = LittleLong(*(unsigned *)buf.u);
		if ( ident == MD4_IDENT ) {
			loaded = R_LoadMD4( mod, buf.u, name );
		} else {
			if ( ident != MD3_IDENT ) {
				ri.Printf (PRINT_WARNING,"RE_RegisterModel: unknown fileid for %s\n", name);
				goto fail;
			}

			loaded = R_LoadMD3( mod, lod, buf.u, name );
		}
		
		ri.FS_FreeFile (buf.v);

		if ( !loaded ) {
			if ( lod == 0 ) {
				goto fail;
			} else {
				break;
			}
		} else {
			mod->numLods++;
			numLoaded++;
			// if we have a valid model and are biased
			// so that we won't see any higher detail ones,
			// stop loading them
//			if ( lod <= r_lodbias->integer ) {
//				break;
//			}
		}
	}

	if ( numLoaded ) {
		// duplicate into higher lod spots that weren't
		// loaded, in case the user changes r_lodbias on the fly
		for ( lod-- ; lod >= 0 ; lod-- ) {
			mod->numLods++;
			mod->md3[lod] = mod->md3[lod+1];
		}

		return mod->index;
	}
#ifdef _DEBUG
	else {
		ri.Printf (PRINT_WARNING,"RE_RegisterModel: couldn't load %s\n", name);
	}
#endif

fail:
	// we still keep the model_t around, so if the model name is asked for
	// again, we won't bother scanning the filesystem
	mod->type = MOD_BAD;
	return 0;
}


/*
=================
R_LoadMD3
=================
*/
static qboolean R_LoadMD3 (model_t *mod, int lod, void *buffer, const char *mod_name ) {
	int					i, j;
	md3Header_t			*pinmodel;
    md3Frame_t			*frame;
	md3Surface_t		*surf;
	md3Shader_t			*shader;
	md3Triangle_t		*tri;
	md3St_t				*st;
	md3XyzNormal_t		*xyz;
	md3Tag_t			*tag;
	int					version;
	int					size;

	pinmodel = (md3Header_t *)buffer;

	version = LittleLong (pinmodel->version);
	if (version != MD3_VERSION) {
		ri.Printf( PRINT_WARNING, "R_LoadMD3: %s has wrong version (%i should be %i)\n",
				 mod_name, version, MD3_VERSION);
		return qfalse;
	}

	mod->type = MOD_MESH;
	size = LittleLong(pinmodel->ofsEnd);
	mod->dataSize += size;
	mod->md3[lod] = ri.Hunk_Alloc( size, h_low );

	Com_Memcpy (mod->md3[lod], buffer, LittleLong(pinmodel->ofsEnd) );

    LL(mod->md3[lod]->ident);
    LL(mod->md3[lod]->version);
    LL(mod->md3[lod]->numFrames);
    LL(mod->md3[lod]->numTags);
    LL(mod->md3[lod]->numSurfaces);
    LL(mod->md3[lod]->ofsFrames);
    LL(mod->md3[lod]->ofsTags);
    LL(mod->md3[lod]->ofsSurfaces);
    LL(mod->md3[lod]->ofsEnd);

	if ( mod->md3[lod]->numFrames < 1 ) {
		ri.Printf( PRINT_WARNING, "R_LoadMD3: %s has no frames\n", mod_name );
		return qfalse;
	}
    
	// swap all the frames
    frame = (md3Frame_t *) ( (byte *)mod->md3[lod] + mod->md3[lod]->ofsFrames );
    for ( i = 0 ; i < mod->md3[lod]->numFrames ; i++, frame++) {
    	frame->radius = LittleFloat( frame->radius );
        for ( j = 0 ; j < 3 ; j++ ) {
            frame->bounds[0][j] = LittleFloat( frame->bounds[0][j] );
            frame->bounds[1][j] = LittleFloat( frame->bounds[1][j] );
	    	frame->localOrigin[j] = LittleFloat( frame->localOrigin[j] );
        }
	}

	// swap all the tags
    tag = (md3Tag_t *) ( (byte *)mod->md3[lod] + mod->md3[lod]->ofsTags );
    for ( i = 0 ; i < mod->md3[lod]->numTags * mod->md3[lod]->numFrames ; i++, tag++) {
        for ( j = 0 ; j < 3 ; j++ ) {
			tag->origin[j] = LittleFloat( tag->origin[j] );
			tag->axis[0][j] = LittleFloat( tag->axis[0][j] );
			tag->axis[1][j] = LittleFloat( tag->axis[1][j] );
			tag->axis[2][j] = LittleFloat( tag->axis[2][j] );
        }
	}

	// swap all the surfaces
	surf = (md3Surface_t *) ( (byte *)mod->md3[lod] + mod->md3[lod]->ofsSurfaces );
	for ( i = 0 ; i < mod->md3[lod]->numSurfaces ; i++) {

        LL(surf->ident);
        LL(surf->flags);
        LL(surf->numFrames);
        LL(surf->numShaders);
        LL(surf->numTriangles);
        LL(surf->ofsTriangles);
        LL(surf->numVerts);
        LL(surf->ofsShaders);
        LL(surf->ofsSt);
        LL(surf->ofsXyzNormals);
        LL(surf->ofsEnd);
		
		if ( surf->numVerts > SHADER_MAX_VERTEXES ) {
			ri.Error (ERR_DROP, "R_LoadMD3: %s has more than %i verts on a surface (%i)",
				mod_name, SHADER_MAX_VERTEXES, surf->numVerts );
		}
		if ( surf->numTriangles*3 > SHADER_MAX_INDEXES ) {
			ri.Error (ERR_DROP, "R_LoadMD3: %s has more than %i triangles on a surface (%i)",
				mod_name, SHADER_MAX_INDEXES / 3, surf->numTriangles );
		}
	
		// change to surface identifier
		surf->ident = SF_MD3;

		// lowercase the surface name so skin compares are faster
		Q_strlwr( surf->name );

		// strip off a trailing _1 or _2
		// this is a crutch for q3data being a mess
		j = strlen( surf->name );
		if ( j > 2 && surf->name[j-2] == '_' ) {
			surf->name[j-2] = 0;
		}

        // register the shaders
        shader = (md3Shader_t *) ( (byte *)surf + surf->ofsShaders );
        for ( j = 0 ; j < surf->numShaders ; j++, shader++ ) {
            shader_t	*sh;

            sh = R_FindShader( shader->name, LIGHTMAP_NONE, qtrue );
			if ( sh->defaultShader ) {
				shader->shaderIndex = 0;
			} else {
				shader->shaderIndex = sh->index;
			}
        }

		// swap all the triangles
		tri = (md3Triangle_t *) ( (byte *)surf + surf->ofsTriangles );
		for ( j = 0 ; j < surf->numTriangles ; j++, tri++ ) {
			LL(tri->indexes[0]);
			LL(tri->indexes[1]);
			LL(tri->indexes[2]);
		}

		// swap all the ST
        st = (md3St_t *) ( (byte *)surf + surf->ofsSt );
        for ( j = 0 ; j < surf->numVerts ; j++, st++ ) {
            st->st[0] = LittleFloat( st->st[0] );
            st->st[1] = LittleFloat( st->st[1] );
        }

		// swap all the XyzNormals
        xyz = (md3XyzNormal_t *) ( (byte *)surf + surf->ofsXyzNormals );
        for ( j = 0 ; j < surf->numVerts * surf->numFrames ; j++, xyz++ ) 
		{
            xyz->xyz[0] = LittleShort( xyz->xyz[0] );
            xyz->xyz[1] = LittleShort( xyz->xyz[1] );
            xyz->xyz[2] = LittleShort( xyz->xyz[2] );

            xyz->normal = LittleShort( xyz->normal );
        }


		// find the next surface
		surf = (md3Surface_t *)( (byte *)surf + surf->ofsEnd );
	}
    
	return qtrue;
}


#ifdef RAVENMD4

/*
=================
R_LoadMDR
=================
*/
static qboolean R_LoadMDR( model_t *mod, void *buffer, int filesize, const char *mod_name ) 
{
	int					i, j, k, l;
	mdrHeader_t			*pinmodel, *mdr;
        mdrFrame_t			*frame;
	mdrLOD_t			*lod, *curlod;
	mdrSurface_t			*surf, *cursurf;
	mdrTriangle_t			*tri, *curtri;
	mdrVertex_t			*v, *curv;
	mdrWeight_t			*weight, *curweight;
	mdrTag_t			*tag, *curtag;
	int					size;
	shader_t			*sh;

	pinmodel = (mdrHeader_t *)buffer;

	pinmodel->version = LittleLong(pinmodel->version);
	if (pinmodel->version != MDR_VERSION) 
	{
		ri.Printf(PRINT_WARNING, "R_LoadMDR: %s has wrong version (%i should be %i)\n", mod_name, pinmodel->version, MDR_VERSION);
		return qfalse;
	}

	size = LittleLong(pinmodel->ofsEnd);
	
	if(size > filesize)
	{
		ri.Printf(PRINT_WARNING, "R_LoadMDR: Header of %s is broken. Wrong filesize declared!\n", mod_name);
		return qfalse;
	}
	
	mod->type = MOD_MDR;

	LL(pinmodel->numFrames);
	LL(pinmodel->numBones);
	LL(pinmodel->ofsFrames);

	// This is a model that uses some type of compressed Bones. We don't want to uncompress every bone for each rendered frame
	// over and over again, we'll uncompress it in this function already, so we must adjust the size of the target md4.
	if(pinmodel->ofsFrames < 0)
	{
		// mdrFrame_t is larger than mdrCompFrame_t:
		size += pinmodel->numFrames * sizeof(frame->name);
		// now add enough space for the uncompressed bones.
		size += pinmodel->numFrames * pinmodel->numBones * ((sizeof(mdrBone_t) - sizeof(mdrCompBone_t)));
	}
	
	// simple bounds check
	if(pinmodel->numBones < 0 ||
		sizeof(*mdr) + pinmodel->numFrames * (sizeof(*frame) + (pinmodel->numBones - 1) * sizeof(*frame->bones)) > size)
	{
		ri.Printf(PRINT_WARNING, "R_LoadMDR: %s has broken structure.\n", mod_name);
		return qfalse;
	}

	mod->dataSize += size;
	mod->md4 = mdr = ri.Hunk_Alloc( size, h_low );

	// Copy all the values over from the file and fix endian issues in the process, if necessary.
	
	mdr->ident = LittleLong(pinmodel->ident);
	mdr->version = pinmodel->version;	// Don't need to swap byte order on this one, we already did above.
	Q_strncpyz(mdr->name, pinmodel->name, sizeof(mdr->name));
	mdr->numFrames = pinmodel->numFrames;
	mdr->numBones = pinmodel->numBones;
	mdr->numLODs = LittleLong(pinmodel->numLODs);
	mdr->numTags = LittleLong(pinmodel->numTags);
	// We don't care about the other offset values, we'll generate them ourselves while loading.

	mod->numLods = mdr->numLODs;

	if ( mdr->numFrames < 1 ) 
	{
		ri.Printf(PRINT_WARNING, "R_LoadMDR: %s has no frames\n", mod_name);
		return qfalse;
	}

	/* The first frame will be put into the first free space after the header */
	frame = (mdrFrame_t *)(mdr + 1);
	mdr->ofsFrames = (int)((byte *) frame - (byte *) mdr);
		
	if (pinmodel->ofsFrames < 0)
	{
		mdrCompFrame_t *cframe;
				
		// compressed model...				
		cframe = (mdrCompFrame_t *)((byte *) pinmodel - pinmodel->ofsFrames);
		
		for(i = 0; i < mdr->numFrames; i++)
		{
			for(j = 0; j < 3; j++)
			{
				frame->bounds[0][j] = LittleFloat(cframe->bounds[0][j]);
				frame->bounds[1][j] = LittleFloat(cframe->bounds[1][j]);
				frame->localOrigin[j] = LittleFloat(cframe->localOrigin[j]);
			}

			frame->radius = LittleFloat(cframe->radius);
			frame->name[0] = '\0';	// No name supplied in the compressed version.
			
			for(j = 0; j < mdr->numBones; j++)
			{
				for(k = 0; k < (sizeof(cframe->bones[j].Comp) / 2); k++)
				{
					// Do swapping for the uncompressing functions. They seem to use shorts
					// values only, so I assume this will work. Never tested it on other
					// platforms, though.
					
					((unsigned short *)(cframe->bones[j].Comp))[k] =
						LittleShort( ((unsigned short *)(cframe->bones[j].Comp))[k] );
				}
				
				/* Now do the actual uncompressing */
				MC_UnCompress(frame->bones[j].matrix, cframe->bones[j].Comp);
			}
			
			// Next Frame...
			cframe = (mdrCompFrame_t *) &cframe->bones[j];
			frame = (mdrFrame_t *) &frame->bones[j];
		}
	}
	else
	{
		mdrFrame_t *curframe;
		
		// uncompressed model...
		//
    
		curframe = (mdrFrame_t *)((byte *) pinmodel + pinmodel->ofsFrames);
		
		// swap all the frames
		for ( i = 0 ; i < mdr->numFrames ; i++) 
		{
			for(j = 0; j < 3; j++)
			{
				frame->bounds[0][j] = LittleFloat(curframe->bounds[0][j]);
				frame->bounds[1][j] = LittleFloat(curframe->bounds[1][j]);
				frame->localOrigin[j] = LittleFloat(curframe->localOrigin[j]);
			}
			
			frame->radius = LittleFloat(curframe->radius);
			Q_strncpyz(frame->name, curframe->name, sizeof(frame->name));
			
			for (j = 0; j < (int) (mdr->numBones * sizeof(mdrBone_t) / 4); j++) 
			{
				((float *)frame->bones)[j] = LittleFloat( ((float *)curframe->bones)[j] );
			}
			
			curframe++;
			frame++;
		}
	}
	
	// frame should now point to the first free address after all frames.
	lod = (mdrLOD_t *) frame;
	mdr->ofsLODs = (int) ((byte *) lod - (byte *)mdr);
	
	curlod = (mdrLOD_t *)((byte *) pinmodel + LittleLong(pinmodel->ofsLODs));
		
	// swap all the LOD's
	for ( l = 0 ; l < mdr->numLODs ; l++)
	{
		// simple bounds check
		if((byte *) (lod + 1) > (byte *) mdr + size)
		{
			ri.Printf(PRINT_WARNING, "R_LoadMDR: %s has broken structure.\n", mod_name);
			return qfalse;
		}

		lod->numSurfaces = LittleLong(curlod->numSurfaces);
		
		// swap all the surfaces
		surf = (mdrSurface_t *) (lod + 1);
		lod->ofsSurfaces = (int)((byte *) surf - (byte *) lod);
		cursurf = (mdrSurface_t *) ((byte *)curlod + LittleLong(curlod->ofsSurfaces));
		
		for ( i = 0 ; i < lod->numSurfaces ; i++)
		{
			// simple bounds check
			if((byte *) (surf + 1) > (byte *) mdr + size)
			{
				ri.Printf(PRINT_WARNING, "R_LoadMDR: %s has broken structure.\n", mod_name);
				return qfalse;
			}

			// first do some copying stuff
			
			surf->ident = SF_MDR;
			Q_strncpyz(surf->name, cursurf->name, sizeof(surf->name));
			Q_strncpyz(surf->shader, cursurf->shader, sizeof(surf->shader));
			
			surf->ofsHeader = (byte *) mdr - (byte *) surf;
			
			surf->numVerts = LittleLong(cursurf->numVerts);
			surf->numTriangles = LittleLong(cursurf->numTriangles);
			// numBoneReferences and BoneReferences generally seem to be unused
			
			// now do the checks that may fail.
			if ( surf->numVerts > SHADER_MAX_VERTEXES ) 
			{
				ri.Printf(PRINT_WARNING, "R_LoadMDR: %s has more than %i verts on a surface (%i)",
					  mod_name, SHADER_MAX_VERTEXES, surf->numVerts );
				return qfalse;
			}
			if ( surf->numTriangles*3 > SHADER_MAX_INDEXES ) 
			{
				ri.Printf(PRINT_WARNING, "R_LoadMDR: %s has more than %i triangles on a surface (%i)",
					  mod_name, SHADER_MAX_INDEXES / 3, surf->numTriangles );
				return qfalse;
			}
			// lowercase the surface name so skin compares are faster
			Q_strlwr( surf->name );

			// register the shaders
			sh = R_FindShader(surf->shader, LIGHTMAP_NONE, qtrue);
			if ( sh->defaultShader ) {
				surf->shaderIndex = 0;
			} else {
				surf->shaderIndex = sh->index;
			}
			
			// now copy the vertexes.
			v = (mdrVertex_t *) (surf + 1);
			surf->ofsVerts = (int)((byte *) v - (byte *) surf);
			curv = (mdrVertex_t *) ((byte *)cursurf + LittleLong(cursurf->ofsVerts));
			
			for(j = 0; j < surf->numVerts; j++)
			{
				LL(curv->numWeights);
			
				// simple bounds check
				if(curv->numWeights < 0 || (byte *) (v + 1) + (curv->numWeights - 1) * sizeof(*weight) > (byte *) mdr + size)
				{
					ri.Printf(PRINT_WARNING, "R_LoadMDR: %s has broken structure.\n", mod_name);
					return qfalse;
				}

				v->normal[0] = LittleFloat(curv->normal[0]);
				v->normal[1] = LittleFloat(curv->normal[1]);
				v->normal[2] = LittleFloat(curv->normal[2]);
				
				v->texCoords[0] = LittleFloat(curv->texCoords[0]);
				v->texCoords[1] = LittleFloat(curv->texCoords[1]);
				
				v->numWeights = curv->numWeights;
				weight = &v->weights[0];
				curweight = &curv->weights[0];
				
				// Now copy all the weights
				for(k = 0; k < v->numWeights; k++)
				{
					weight->boneIndex = LittleLong(curweight->boneIndex);
					weight->boneWeight = LittleFloat(curweight->boneWeight);
					
					weight->offset[0] = LittleFloat(curweight->offset[0]);
					weight->offset[1] = LittleFloat(curweight->offset[1]);
					weight->offset[2] = LittleFloat(curweight->offset[2]);
					
					weight++;
					curweight++;
				}
				
				v = (mdrVertex_t *) weight;
				curv = (mdrVertex_t *) curweight;
			}
						
			// we know the offset to the triangles now:
			tri = (mdrTriangle_t *) v;
			surf->ofsTriangles = (int)((byte *) tri - (byte *) surf);
			curtri = (mdrTriangle_t *)((byte *) cursurf + LittleLong(cursurf->ofsTriangles));
			
			// simple bounds check
			if(surf->numTriangles < 0 || (byte *) (tri + surf->numTriangles) > (byte *) mdr + size)
			{
				ri.Printf(PRINT_WARNING, "R_LoadMDR: %s has broken structure.\n", mod_name);
				return qfalse;
			}

			for(j = 0; j < surf->numTriangles; j++)
			{
				tri->indexes[0] = LittleLong(curtri->indexes[0]);
				tri->indexes[1] = LittleLong(curtri->indexes[1]);
				tri->indexes[2] = LittleLong(curtri->indexes[2]);
				
				tri++;
				curtri++;
			}
			
			// tri now points to the end of the surface.
			surf->ofsEnd = (byte *) tri - (byte *) surf;
			surf = (mdrSurface_t *) tri;

			// find the next surface.
			cursurf = (mdrSurface_t *) ((byte *) cursurf + LittleLong(cursurf->ofsEnd));
		}

		// surf points to the next lod now.
		lod->ofsEnd = (int)((byte *) surf - (byte *) lod);
		lod = (mdrLOD_t *) surf;

		// find the next LOD.
		curlod = (mdrLOD_t *)((byte *) curlod + LittleLong(curlod->ofsEnd));
	}
	
	// lod points to the first tag now, so update the offset too.
	tag = (mdrTag_t *) lod;
	mdr->ofsTags = (int)((byte *) tag - (byte *) mdr);
	curtag = (mdrTag_t *) ((byte *)pinmodel + LittleLong(pinmodel->ofsTags));

	// simple bounds check
	if(mdr->numTags < 0 || (byte *) (tag + mdr->numTags) > (byte *) mdr + size)
	{
		ri.Printf(PRINT_WARNING, "R_LoadMDR: %s has broken structure.\n", mod_name);
		return qfalse;
	}
	
	for (i = 0 ; i < mdr->numTags ; i++)
	{
		tag->boneIndex = LittleLong(curtag->boneIndex);
		Q_strncpyz(tag->name, curtag->name, sizeof(tag->name));
		
		tag++;
		curtag++;
	}
	
	// And finally we know the real offset to the end.
	mdr->ofsEnd = (int)((byte *) tag - (byte *) mdr);

	// phew! we're done.
	
	return qtrue;
}
#endif

/*
=================
R_LoadMD4
=================
*/

static qboolean R_LoadMD4( model_t *mod, void *buffer, const char *mod_name ) {
	int					i, j, k, lodindex;
	md4Header_t			*pinmodel, *md4;
    md4Frame_t			*frame;
	md4LOD_t			*lod;
	md4Surface_t		*surf;
	md4Triangle_t		*tri;
	md4Vertex_t			*v;
	int					version;
	int					size;
	shader_t			*sh;
	int					frameSize;

	pinmodel = (md4Header_t *)buffer;

	version = LittleLong (pinmodel->version);
	if (version != MD4_VERSION) {
		ri.Printf( PRINT_WARNING, "R_LoadMD4: %s has wrong version (%i should be %i)\n",
				 mod_name, version, MD4_VERSION);
		return qfalse;
	}

	mod->type = MOD_MD4;
	size = LittleLong(pinmodel->ofsEnd);
	mod->dataSize += size;
	md4 = mod->md4 = ri.Hunk_Alloc( size, h_low );

	Com_Memcpy(md4, buffer, size);

    LL(md4->ident);
    LL(md4->version);
    LL(md4->numFrames);
    LL(md4->numBones);
    LL(md4->numLODs);
    LL(md4->ofsFrames);
    LL(md4->ofsLODs);
    md4->ofsEnd = size;

	if ( md4->numFrames < 1 ) {
		ri.Printf( PRINT_WARNING, "R_LoadMD4: %s has no frames\n", mod_name );
		return qfalse;
	}

    // we don't need to swap tags in the renderer, they aren't used
    
	// swap all the frames
	frameSize = (size_t)( &((md4Frame_t *)0)->bones[ md4->numBones ] );
    for ( i = 0 ; i < md4->numFrames ; i++, frame++) {
	    frame = (md4Frame_t *) ( (byte *)md4 + md4->ofsFrames + i * frameSize );
    	frame->radius = LittleFloat( frame->radius );
        for ( j = 0 ; j < 3 ; j++ ) {
            frame->bounds[0][j] = LittleFloat( frame->bounds[0][j] );
            frame->bounds[1][j] = LittleFloat( frame->bounds[1][j] );
	    	frame->localOrigin[j] = LittleFloat( frame->localOrigin[j] );
        }
		for ( j = 0 ; j < md4->numBones * sizeof( md4Bone_t ) / 4 ; j++ ) {
			((float *)frame->bones)[j] = LittleFloat( ((float *)frame->bones)[j] );
		}
	}

	// swap all the LOD's
	lod = (md4LOD_t *) ( (byte *)md4 + md4->ofsLODs );
	for ( lodindex = 0 ; lodindex < md4->numLODs ; lodindex++ ) {

		// swap all the surfaces
		surf = (md4Surface_t *) ( (byte *)lod + lod->ofsSurfaces );
		for ( i = 0 ; i < lod->numSurfaces ; i++) {
			LL(surf->ident);
			LL(surf->numTriangles);
			LL(surf->ofsTriangles);
			LL(surf->numVerts);
			LL(surf->ofsVerts);
			LL(surf->ofsEnd);
			
			if ( surf->numVerts > SHADER_MAX_VERTEXES ) {
				ri.Error (ERR_DROP, "R_LoadMD3: %s has more than %i verts on a surface (%i)",
					mod_name, SHADER_MAX_VERTEXES, surf->numVerts );
			}
			if ( surf->numTriangles*3 > SHADER_MAX_INDEXES ) {
				ri.Error (ERR_DROP, "R_LoadMD3: %s has more than %i triangles on a surface (%i)",
					mod_name, SHADER_MAX_INDEXES / 3, surf->numTriangles );
			}

			// change to surface identifier
			surf->ident = SF_MD4;

			// lowercase the surface name so skin compares are faster
			Q_strlwr( surf->name );
		
			// register the shaders
			sh = R_FindShader( surf->shader, LIGHTMAP_NONE, qtrue );
			if ( sh->defaultShader ) {
				surf->shaderIndex = 0;
			} else {
				surf->shaderIndex = sh->index;
			}

			// swap all the triangles
			tri = (md4Triangle_t *) ( (byte *)surf + surf->ofsTriangles );
			for ( j = 0 ; j < surf->numTriangles ; j++, tri++ ) {
				LL(tri->indexes[0]);
				LL(tri->indexes[1]);
				LL(tri->indexes[2]);
			}

			// swap all the vertexes
			// FIXME
			// This makes TFC's skeletons work.  Shouldn't be necessary anymore, but left
			// in for reference.
			//v = (md4Vertex_t *) ( (byte *)surf + surf->ofsVerts + 12);
			v = (md4Vertex_t *) ( (byte *)surf + surf->ofsVerts);
			for ( j = 0 ; j < surf->numVerts ; j++ ) {
				v->normal[0] = LittleFloat( v->normal[0] );
				v->normal[1] = LittleFloat( v->normal[1] );
				v->normal[2] = LittleFloat( v->normal[2] );

				v->texCoords[0] = LittleFloat( v->texCoords[0] );
				v->texCoords[1] = LittleFloat( v->texCoords[1] );

				v->numWeights = LittleLong( v->numWeights );

				for ( k = 0 ; k < v->numWeights ; k++ ) {
					v->weights[k].boneIndex = LittleLong( v->weights[k].boneIndex );
					v->weights[k].boneWeight = LittleFloat( v->weights[k].boneWeight );
				   v->weights[k].offset[0] = LittleFloat( v->weights[k].offset[0] );
				   v->weights[k].offset[1] = LittleFloat( v->weights[k].offset[1] );
				   v->weights[k].offset[2] = LittleFloat( v->weights[k].offset[2] );
				}
				// FIXME
				// This makes TFC's skeletons work.  Shouldn't be necessary anymore, but left
				// in for reference.
				//v = (md4Vertex_t *)( ( byte * )&v->weights[v->numWeights] + 12 );
				v = (md4Vertex_t *)( ( byte * )&v->weights[v->numWeights]);
			}

			// find the next surface
			surf = (md4Surface_t *)( (byte *)surf + surf->ofsEnd );
		}

		// find the next LOD
		lod = (md4LOD_t *)( (byte *)lod + lod->ofsEnd );
	}

	return qtrue;
}



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

/*
** RE_BeginRegistration
*/
void RE_BeginRegistration( glconfig_t *glconfigOut ) {

	R_Init();

	*glconfigOut = glConfig;

	R_SyncRenderThread();

	tr.viewCluster = -1;		// force markleafs to regenerate
	R_ClearFlares();
	RE_ClearScene();

	tr.registered = qtrue;

	// NOTE: this sucks, for some reason the first stretch pic is never drawn
	// without this we'd see a white flash on a level load because the very
	// first time the level shot would not be drawn
//	RE_StretchPic(0, 0, 0, 0, 0, 0, 1, 1, 0);
}

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

/*
===============
R_ModelInit
===============
*/
void R_ModelInit( void ) {
	model_t		*mod;

	// leave a space for NULL model
	tr.numModels = 0;

	mod = R_AllocModel();
	mod->type = MOD_BAD;
}


/*
================
R_Modellist_f
================
*/
void R_Modellist_f( void ) {
	int		i, j;
	model_t	*mod;
	int		total;
	int		lods;

	total = 0;
	for ( i = 1 ; i < tr.numModels; i++ ) {
		mod = tr.models[i];
		lods = 1;
		for ( j = 1 ; j < MD3_MAX_LODS ; j++ ) {
			if ( mod->md3[j] && mod->md3[j] != mod->md3[j-1] ) {
				lods++;
			}
		}
		ri.Printf( PRINT_ALL, "%8i : (%i) %s\n",mod->dataSize, lods, mod->name );
		total += mod->dataSize;
	}
	ri.Printf( PRINT_ALL, "%8i : Total models\n", total );

#if	0		// not working right with new hunk
	if ( tr.world ) {
		ri.Printf( PRINT_ALL, "\n%8i : %s\n", tr.world->dataSize, tr.world->name );
	}
#endif
}


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


/*
================
R_GetTag
================
*/
static md3Tag_t *R_GetTag( md3Header_t *mod, int frame, const char *tagName ) {
	md3Tag_t		*tag;
	int				i;

	if ( frame >= mod->numFrames ) {
		// it is possible to have a bad frame while changing models, so don't error
		frame = mod->numFrames - 1;
	}

	tag = (md3Tag_t *)((byte *)mod + mod->ofsTags) + frame * mod->numTags;
	for ( i = 0 ; i < mod->numTags ; i++, tag++ ) {
		if ( !strcmp( tag->name, tagName ) ) {
			return tag;	// found it
		}
	}

	return NULL;
}

#ifdef RAVENMD4
void R_GetAnimTag( mdrHeader_t *mod, int framenum, const char *tagName, md3Tag_t * dest) 
{
	int				i, j, k;
	int				frameSize;
	mdrFrame_t		*frame;
	mdrTag_t		*tag;

	if ( framenum >= mod->numFrames ) 
	{
		// it is possible to have a bad frame while changing models, so don't error
		framenum = mod->numFrames - 1;
	}

	tag = (mdrTag_t *)((byte *)mod + mod->ofsTags);
	for ( i = 0 ; i < mod->numTags ; i++, tag++ )
	{
		if ( !strcmp( tag->name, tagName ) )
		{
			Q_strncpyz(dest->name, tag->name, sizeof(dest->name));

			// uncompressed model...
			//
			frameSize = (long)( &((mdrFrame_t *)0)->bones[ mod->numBones ] );
			frame = (mdrFrame_t *)((byte *)mod + mod->ofsFrames + framenum * frameSize );

			for (j = 0; j < 3; j++)
			{
				for (k = 0; k < 3; k++)
					dest->axis[j][k]=frame->bones[tag->boneIndex].matrix[k][j];
			}

			dest->origin[0]=frame->bones[tag->boneIndex].matrix[0][3];
			dest->origin[1]=frame->bones[tag->boneIndex].matrix[1][3];
			dest->origin[2]=frame->bones[tag->boneIndex].matrix[2][3];				

			return;
		}
	}

	AxisClear( dest->axis );
	VectorClear( dest->origin );
	strcpy(dest->name,"");
}
#endif

/*
================
R_LerpTag
================
*/
int R_LerpTag( orientation_t *tag, qhandle_t handle, int startFrame, int endFrame, 
					 float frac, const char *tagName ) {
	md3Tag_t	*start, *end;
#ifdef RAVENMD4
	md3Tag_t	start_space, end_space;
#endif
	int		i;
	float		frontLerp, backLerp;
	model_t		*model;

	model = R_GetModelByHandle( handle );
	if ( !model->md3[0] )
	{
#ifdef RAVENMD4
		if(model->md4)
		{
			start = &start_space;
			end = &end_space;
			R_GetAnimTag((mdrHeader_t *) model->md4, startFrame, tagName, start);
			R_GetAnimTag((mdrHeader_t *) model->md4, endFrame, tagName, end);
		}
		else
#endif
		{

			AxisClear( tag->axis );
			VectorClear( tag->origin );
			return qfalse;

		}
	}
	else
	{
		start = R_GetTag( model->md3[0], startFrame, tagName );
		end = R_GetTag( model->md3[0], endFrame, tagName );
		if ( !start || !end ) {
			AxisClear( tag->axis );
			VectorClear( tag->origin );
			return qfalse;
		}
	}
	
	frontLerp = frac;
	backLerp = 1.0f - frac;

	for ( i = 0 ; i < 3 ; i++ ) {
		tag->origin[i] = start->origin[i] * backLerp +  end->origin[i] * frontLerp;
		tag->axis[0][i] = start->axis[0][i] * backLerp +  end->axis[0][i] * frontLerp;
		tag->axis[1][i] = start->axis[1][i] * backLerp +  end->axis[1][i] * frontLerp;
		tag->axis[2][i] = start->axis[2][i] * backLerp +  end->axis[2][i] * frontLerp;
	}
	VectorNormalize( tag->axis[0] );
	VectorNormalize( tag->axis[1] );
	VectorNormalize( tag->axis[2] );
	return qtrue;
}


/*
====================
R_ModelBounds
====================
*/
void R_ModelBounds( qhandle_t handle, vec3_t mins, vec3_t maxs ) {
	model_t		*model;
	md3Header_t	*header;
	md3Frame_t	*frame;

	model = R_GetModelByHandle( handle );

	if ( model->bmodel ) {
		VectorCopy( model->bmodel->bounds[0], mins );
		VectorCopy( model->bmodel->bounds[1], maxs );
		return;
	}

	if ( !model->md3[0] ) {
		VectorClear( mins );
		VectorClear( maxs );
		return;
	}

	header = model->md3[0];

	frame = (md3Frame_t *)( (byte *)header + header->ofsFrames );

	VectorCopy( frame->bounds[0], mins );
	VectorCopy( frame->bounds[1], maxs );
}