/*
===========================================================================

Return to Castle Wolfenstein single player GPL Source Code
Copyright (C) 1999-2010 id Software LLC, a ZeniMax Media company. 

This file is part of the Return to Castle Wolfenstein single player GPL Source Code (RTCW SP Source Code).  

RTCW SP 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 3 of the License, or
(at your option) any later version.

RTCW SP 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 RTCW SP Source Code.  If not, see <http://www.gnu.org/licenses/>.

In addition, the RTCW SP Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the RTCW SP Source Code.  If not, please request a copy in writing from id Software at the address below.

If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.

===========================================================================
*/

// tr_surf.c
#include "tr_local.h"
#if idppc_altivec && !defined(MACOS_X)
#include <altivec.h>
#endif

/*

  THIS ENTIRE FILE IS BACK END

backEnd.currentEntity will be valid.

Tess_Begin has already been called for the surface's shader.

The modelview matrix will be set.

It is safe to actually issue drawing commands here if you don't want to
use the shader system.
*/


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


/*
==============
RB_CheckOverflow
==============
*/
void RB_CheckOverflow( int verts, int indexes ) {
	if ( tess.numVertexes + verts < SHADER_MAX_VERTEXES
		 && tess.numIndexes + indexes < SHADER_MAX_INDEXES ) {
		return;
	}

	RB_EndSurface();

	if ( verts >= SHADER_MAX_VERTEXES ) {
		ri.Error( ERR_DROP, "RB_CheckOverflow: verts > MAX (%d > %d)", verts, SHADER_MAX_VERTEXES );
	}
	if ( indexes >= SHADER_MAX_INDEXES ) {
		ri.Error( ERR_DROP, "RB_CheckOverflow: indices > MAX (%d > %d)", indexes, SHADER_MAX_INDEXES );
	}

	RB_BeginSurface( tess.shader, tess.fogNum );
}

/*
==============
RB_AddQuadStampExt
==============
*/
void RB_AddQuadStampExt( vec3_t origin, vec3_t left, vec3_t up, byte *color, float s1, float t1, float s2, float t2 ) {
	vec3_t normal;
	int ndx;

	RB_CHECKOVERFLOW( 4, 6 );

	ndx = tess.numVertexes;

	// triangle indexes for a simple quad
	tess.indexes[ tess.numIndexes ] = ndx;
	tess.indexes[ tess.numIndexes + 1 ] = ndx + 1;
	tess.indexes[ tess.numIndexes + 2 ] = ndx + 3;

	tess.indexes[ tess.numIndexes + 3 ] = ndx + 3;
	tess.indexes[ tess.numIndexes + 4 ] = ndx + 1;
	tess.indexes[ tess.numIndexes + 5 ] = ndx + 2;

	tess.xyz[ndx][0] = origin[0] + left[0] + up[0];
	tess.xyz[ndx][1] = origin[1] + left[1] + up[1];
	tess.xyz[ndx][2] = origin[2] + left[2] + up[2];

	tess.xyz[ndx + 1][0] = origin[0] - left[0] + up[0];
	tess.xyz[ndx + 1][1] = origin[1] - left[1] + up[1];
	tess.xyz[ndx + 1][2] = origin[2] - left[2] + up[2];

	tess.xyz[ndx + 2][0] = origin[0] - left[0] - up[0];
	tess.xyz[ndx + 2][1] = origin[1] - left[1] - up[1];
	tess.xyz[ndx + 2][2] = origin[2] - left[2] - up[2];

	tess.xyz[ndx + 3][0] = origin[0] + left[0] - up[0];
	tess.xyz[ndx + 3][1] = origin[1] + left[1] - up[1];
	tess.xyz[ndx + 3][2] = origin[2] + left[2] - up[2];


	// constant normal all the way around
	VectorSubtract( vec3_origin, backEnd.viewParms.or.axis[0], normal );

	tess.normal[ndx][0] = tess.normal[ndx + 1][0] = tess.normal[ndx + 2][0] = tess.normal[ndx + 3][0] = normal[0];
	tess.normal[ndx][1] = tess.normal[ndx + 1][1] = tess.normal[ndx + 2][1] = tess.normal[ndx + 3][1] = normal[1];
	tess.normal[ndx][2] = tess.normal[ndx + 1][2] = tess.normal[ndx + 2][2] = tess.normal[ndx + 3][2] = normal[2];

	// standard square texture coordinates
	tess.texCoords[ndx][0][0] = tess.texCoords[ndx][1][0] = s1;
	tess.texCoords[ndx][0][1] = tess.texCoords[ndx][1][1] = t1;

	tess.texCoords[ndx + 1][0][0] = tess.texCoords[ndx + 1][1][0] = s2;
	tess.texCoords[ndx + 1][0][1] = tess.texCoords[ndx + 1][1][1] = t1;

	tess.texCoords[ndx + 2][0][0] = tess.texCoords[ndx + 2][1][0] = s2;
	tess.texCoords[ndx + 2][0][1] = tess.texCoords[ndx + 2][1][1] = t2;

	tess.texCoords[ndx + 3][0][0] = tess.texCoords[ndx + 3][1][0] = s1;
	tess.texCoords[ndx + 3][0][1] = tess.texCoords[ndx + 3][1][1] = t2;

	// constant color all the way around
	// should this be identity and let the shader specify from entity?
	*( unsigned int * ) &tess.vertexColors[ndx] =
		*( unsigned int * ) &tess.vertexColors[ndx + 1] =
			*( unsigned int * ) &tess.vertexColors[ndx + 2] =
				*( unsigned int * ) &tess.vertexColors[ndx + 3] =
					*( unsigned int * )color;


	tess.numVertexes += 4;
	tess.numIndexes += 6;
}

/*
==============
RB_AddQuadStamp
==============
*/
void RB_AddQuadStamp( vec3_t origin, vec3_t left, vec3_t up, byte *color ) {
	RB_AddQuadStampExt( origin, left, up, color, 0, 0, 1, 1 );
}

/*
==============
RB_SurfaceSplash
==============
*/
static void RB_SurfaceSplash( void ) {
	vec3_t left, up;
	float radius;

	// calculate the xyz locations for the four corners
	radius = backEnd.currentEntity->e.radius;

	VectorSet( left, -radius, 0, 0 );
	VectorSet( up, 0, radius, 0 );
	if ( backEnd.viewParms.isMirror ) {
		VectorSubtract( vec3_origin, left, left );
	}

	RB_AddQuadStamp( backEnd.currentEntity->e.origin, left, up, backEnd.currentEntity->e.shaderRGBA );
}

/*
==============
RB_SurfaceSprite
==============
*/
static void RB_SurfaceSprite( void ) {
	vec3_t left, up;
	float radius;

	// calculate the xyz locations for the four corners
	radius = backEnd.currentEntity->e.radius;
	if ( backEnd.currentEntity->e.rotation == 0 ) {
		VectorScale( backEnd.viewParms.or.axis[1], radius, left );
		VectorScale( backEnd.viewParms.or.axis[2], radius, up );
	} else {
		float s, c;
		float ang;

		ang = M_PI * backEnd.currentEntity->e.rotation / 180;
		s = sin( ang );
		c = cos( ang );

		VectorScale( backEnd.viewParms.or.axis[1], c * radius, left );
		VectorMA( left, -s * radius, backEnd.viewParms.or.axis[2], left );

		VectorScale( backEnd.viewParms.or.axis[2], c * radius, up );
		VectorMA( up, s * radius, backEnd.viewParms.or.axis[1], up );
	}
	if ( backEnd.viewParms.isMirror ) {
		VectorSubtract( vec3_origin, left, left );
	}

	RB_AddQuadStamp( backEnd.currentEntity->e.origin, left, up, backEnd.currentEntity->e.shaderRGBA );
}


/*
=============
RB_SurfacePolychain
=============
*/
static void RB_SurfacePolychain( srfPoly_t *p ) {
	int i;
	int numv;

	RB_CHECKOVERFLOW( p->numVerts, 3 * ( p->numVerts - 2 ) );

	// fan triangles into the tess array
	numv = tess.numVertexes;
	for ( i = 0; i < p->numVerts; i++ ) {
		VectorCopy( p->verts[i].xyz, tess.xyz[numv] );
		tess.texCoords[numv][0][0] = p->verts[i].st[0];
		tess.texCoords[numv][0][1] = p->verts[i].st[1];
		*(int *)&tess.vertexColors[numv] = *(int *)p->verts[ i ].modulate;

		numv++;
	}

	// generate fan indexes into the tess array
	for ( i = 0; i < p->numVerts - 2; i++ ) {
		tess.indexes[tess.numIndexes + 0] = tess.numVertexes;
		tess.indexes[tess.numIndexes + 1] = tess.numVertexes + i + 1;
		tess.indexes[tess.numIndexes + 2] = tess.numVertexes + i + 2;
		tess.numIndexes += 3;
	}

	tess.numVertexes = numv;
}


/*
=============
RB_SurfaceTriangles
=============
*/
static void RB_SurfaceTriangles( srfTriangles_t *srf ) {
	int i;
	drawVert_t  *dv;
	float       *xyz, *normal, *texCoords;
	byte        *color;
	int dlightBits;
	qboolean needsNormal;

	dlightBits = srf->dlightBits;
	tess.dlightBits |= dlightBits;

	RB_CHECKOVERFLOW( srf->numVerts, srf->numIndexes );

	for ( i = 0 ; i < srf->numIndexes ; i += 3 ) {
		tess.indexes[ tess.numIndexes + i + 0 ] = tess.numVertexes + srf->indexes[ i + 0 ];
		tess.indexes[ tess.numIndexes + i + 1 ] = tess.numVertexes + srf->indexes[ i + 1 ];
		tess.indexes[ tess.numIndexes + i + 2 ] = tess.numVertexes + srf->indexes[ i + 2 ];
	}
	tess.numIndexes += srf->numIndexes;

	dv = srf->verts;
	xyz = tess.xyz[ tess.numVertexes ];
	normal = tess.normal[ tess.numVertexes ];
	texCoords = tess.texCoords[ tess.numVertexes ][0];
	color = tess.vertexColors[ tess.numVertexes ];
	needsNormal = tess.shader->needsNormal;

	for ( i = 0 ; i < srf->numVerts ; i++, dv++, xyz += 4, normal += 4, texCoords += 4, color += 4 ) {
		xyz[0] = dv->xyz[0];
		xyz[1] = dv->xyz[1];
		xyz[2] = dv->xyz[2];

		if ( needsNormal ) {
			normal[0] = dv->normal[0];
			normal[1] = dv->normal[1];
			normal[2] = dv->normal[2];
		}

		texCoords[0] = dv->st[0];
		texCoords[1] = dv->st[1];

		texCoords[2] = dv->lightmap[0];
		texCoords[3] = dv->lightmap[1];

		*(int *)color = *(int *)dv->color;
	}

	for ( i = 0 ; i < srf->numVerts ; i++ ) {
		tess.vertexDlightBits[ tess.numVertexes + i] = dlightBits;
	}

	tess.numVertexes += srf->numVerts;
}



/*
==============
RB_SurfaceBeam
==============
*/
static void RB_SurfaceBeam( void ) {
#define NUM_BEAM_SEGS 6
	refEntity_t *e;
	int i;
	vec3_t perpvec;
	vec3_t direction, normalized_direction;
	vec3_t start_points[NUM_BEAM_SEGS], end_points[NUM_BEAM_SEGS];
	vec3_t oldorigin, origin;

	e = &backEnd.currentEntity->e;

	oldorigin[0] = e->oldorigin[0];
	oldorigin[1] = e->oldorigin[1];
	oldorigin[2] = e->oldorigin[2];

	origin[0] = e->origin[0];
	origin[1] = e->origin[1];
	origin[2] = e->origin[2];

	normalized_direction[0] = direction[0] = oldorigin[0] - origin[0];
	normalized_direction[1] = direction[1] = oldorigin[1] - origin[1];
	normalized_direction[2] = direction[2] = oldorigin[2] - origin[2];

	if ( VectorNormalize( normalized_direction ) == 0 ) {
		return;
	}

	PerpendicularVector( perpvec, normalized_direction );

	VectorScale( perpvec, 4, perpvec );

	for ( i = 0; i < NUM_BEAM_SEGS ; i++ )
	{
		RotatePointAroundVector( start_points[i], normalized_direction, perpvec, ( 360.0 / NUM_BEAM_SEGS ) * i );
//		VectorAdd( start_points[i], origin, start_points[i] );
		VectorAdd( start_points[i], direction, end_points[i] );
	}

	GL_Bind( tr.whiteImage );

	GL_State( GLS_SRCBLEND_ONE | GLS_DSTBLEND_ONE );

	qglColor3f( 1, 0, 0 );

#ifdef USE_OPENGLES
	GLboolean text = qglIsEnabled(GL_TEXTURE_COORD_ARRAY);
	GLboolean glcol = qglIsEnabled(GL_COLOR_ARRAY);
	if (glcol)
		qglDisableClientState(GL_COLOR_ARRAY);
	if (text)
		qglDisableClientState( GL_TEXTURE_COORD_ARRAY );
	GLfloat vtx[NUM_BEAM_SEGS*6+6];
	for ( i = 0; i <= NUM_BEAM_SEGS; i++ ) {
		memcpy(vtx+i*6, start_points[ i % NUM_BEAM_SEGS], sizeof(GLfloat)*3);
		memcpy(vtx+i*6+3, end_points[ i % NUM_BEAM_SEGS], sizeof(GLfloat)*3);
	}
	qglVertexPointer (3, GL_FLOAT, 0, vtx);
	qglDrawArrays(GL_TRIANGLE_STRIP, 0, NUM_BEAM_SEGS*2+2);
	if (glcol)
		qglEnableClientState(GL_COLOR_ARRAY);
	if (text)
		qglEnableClientState( GL_TEXTURE_COORD_ARRAY );
#else
	qglBegin( GL_TRIANGLE_STRIP );
	for ( i = 0; i <= NUM_BEAM_SEGS; i++ ) {
		qglVertex3fv( start_points[ i % NUM_BEAM_SEGS] );
		qglVertex3fv( end_points[ i % NUM_BEAM_SEGS] );
	}
	qglEnd();
#endif
}

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

static void DoRailCore( const vec3_t start, const vec3_t end, const vec3_t up, float len, float spanWidth ) {
	float spanWidth2;
	int vbase;
	float t = len / 256.0f;

	RB_CHECKOVERFLOW( 4, 6 );

	vbase = tess.numVertexes;

	spanWidth2 = -spanWidth;

	// FIXME: use quad stamp?
	VectorMA( start, spanWidth, up, tess.xyz[tess.numVertexes] );
	tess.texCoords[tess.numVertexes][0][0] = 0;
	tess.texCoords[tess.numVertexes][0][1] = 0;
	tess.vertexColors[tess.numVertexes][0] = backEnd.currentEntity->e.shaderRGBA[0] * 0.25;
	tess.vertexColors[tess.numVertexes][1] = backEnd.currentEntity->e.shaderRGBA[1] * 0.25;
	tess.vertexColors[tess.numVertexes][2] = backEnd.currentEntity->e.shaderRGBA[2] * 0.25;
	tess.numVertexes++;

	VectorMA( start, spanWidth2, up, tess.xyz[tess.numVertexes] );
	tess.texCoords[tess.numVertexes][0][0] = 0;
	tess.texCoords[tess.numVertexes][0][1] = 1;
	tess.vertexColors[tess.numVertexes][0] = backEnd.currentEntity->e.shaderRGBA[0];
	tess.vertexColors[tess.numVertexes][1] = backEnd.currentEntity->e.shaderRGBA[1];
	tess.vertexColors[tess.numVertexes][2] = backEnd.currentEntity->e.shaderRGBA[2];
	tess.numVertexes++;

	VectorMA( end, spanWidth, up, tess.xyz[tess.numVertexes] );

	tess.texCoords[tess.numVertexes][0][0] = t;
	tess.texCoords[tess.numVertexes][0][1] = 0;
	tess.vertexColors[tess.numVertexes][0] = backEnd.currentEntity->e.shaderRGBA[0];
	tess.vertexColors[tess.numVertexes][1] = backEnd.currentEntity->e.shaderRGBA[1];
	tess.vertexColors[tess.numVertexes][2] = backEnd.currentEntity->e.shaderRGBA[2];
	tess.numVertexes++;

	VectorMA( end, spanWidth2, up, tess.xyz[tess.numVertexes] );
	tess.texCoords[tess.numVertexes][0][0] = t;
	tess.texCoords[tess.numVertexes][0][1] = 1;
	tess.vertexColors[tess.numVertexes][0] = backEnd.currentEntity->e.shaderRGBA[0];
	tess.vertexColors[tess.numVertexes][1] = backEnd.currentEntity->e.shaderRGBA[1];
	tess.vertexColors[tess.numVertexes][2] = backEnd.currentEntity->e.shaderRGBA[2];
	tess.numVertexes++;

	tess.indexes[tess.numIndexes++] = vbase;
	tess.indexes[tess.numIndexes++] = vbase + 1;
	tess.indexes[tess.numIndexes++] = vbase + 2;

	tess.indexes[tess.numIndexes++] = vbase + 2;
	tess.indexes[tess.numIndexes++] = vbase + 1;
	tess.indexes[tess.numIndexes++] = vbase + 3;
}

static void DoRailDiscs( int numSegs, const vec3_t start, const vec3_t dir, const vec3_t right, const vec3_t up ) {
	int i;
	vec3_t pos[4];
	vec3_t v;
	int spanWidth = r_railWidth->integer;
	float c, s;
	float scale;

	if ( numSegs > 1 ) {
		numSegs--;
	}
	if ( !numSegs ) {
		return;
	}

	scale = 0.25;

	for ( i = 0; i < 4; i++ )
	{
		c = cos( DEG2RAD( 45 + i * 90 ) );
		s = sin( DEG2RAD( 45 + i * 90 ) );
		v[0] = ( right[0] * c + up[0] * s ) * scale * spanWidth;
		v[1] = ( right[1] * c + up[1] * s ) * scale * spanWidth;
		v[2] = ( right[2] * c + up[2] * s ) * scale * spanWidth;
		VectorAdd( start, v, pos[i] );

		if ( numSegs > 1 ) {
			// offset by 1 segment if we're doing a long distance shot
			VectorAdd( pos[i], dir, pos[i] );
		}
	}

	for ( i = 0; i < numSegs; i++ )
	{
		int j;

		RB_CHECKOVERFLOW( 4, 6 );

		for ( j = 0; j < 4; j++ )
		{
			VectorCopy( pos[j], tess.xyz[tess.numVertexes] );
			tess.texCoords[tess.numVertexes][0][0] = ( j < 2 );
			tess.texCoords[tess.numVertexes][0][1] = ( j && j != 3 );
			tess.vertexColors[tess.numVertexes][0] = backEnd.currentEntity->e.shaderRGBA[0];
			tess.vertexColors[tess.numVertexes][1] = backEnd.currentEntity->e.shaderRGBA[1];
			tess.vertexColors[tess.numVertexes][2] = backEnd.currentEntity->e.shaderRGBA[2];
			tess.numVertexes++;

			VectorAdd( pos[j], dir, pos[j] );
		}

		tess.indexes[tess.numIndexes++] = tess.numVertexes - 4 + 0;
		tess.indexes[tess.numIndexes++] = tess.numVertexes - 4 + 1;
		tess.indexes[tess.numIndexes++] = tess.numVertexes - 4 + 3;
		tess.indexes[tess.numIndexes++] = tess.numVertexes - 4 + 3;
		tess.indexes[tess.numIndexes++] = tess.numVertexes - 4 + 1;
		tess.indexes[tess.numIndexes++] = tess.numVertexes - 4 + 2;
	}
}

/*
** RB_SurfaceRailRinges
*/
static void RB_SurfaceRailRings( void ) {
	refEntity_t *e;
	int numSegs;
	int len;
	vec3_t vec;
	vec3_t right, up;
	vec3_t start, end;

	e = &backEnd.currentEntity->e;

	VectorCopy( e->oldorigin, start );
	VectorCopy( e->origin, end );

	// compute variables
	VectorSubtract( end, start, vec );
	len = VectorNormalize( vec );
	MakeNormalVectors( vec, right, up );
	numSegs = ( len ) / r_railSegmentLength->value;
	if ( numSegs <= 0 ) {
		numSegs = 1;
	}

	VectorScale( vec, r_railSegmentLength->value, vec );

	DoRailDiscs( numSegs, start, vec, right, up );
}

/*
** RB_SurfaceRailCore
*/
static void RB_SurfaceRailCore( void ) {
	refEntity_t *e;
	int len;
	vec3_t right;
	vec3_t vec;
	vec3_t start, end;
	vec3_t v1, v2;

	e = &backEnd.currentEntity->e;

	VectorCopy( e->oldorigin, start );
	VectorCopy( e->origin, end );

	VectorSubtract( end, start, vec );
	len = VectorNormalize( vec );

	// compute side vector
	VectorSubtract( start, backEnd.viewParms.or.origin, v1 );
	VectorNormalize( v1 );
	VectorSubtract( end, backEnd.viewParms.or.origin, v2 );
	VectorNormalize( v2 );
	CrossProduct( v1, v2, right );
	VectorNormalize( right );

	DoRailCore( start, end, right, len, r_railCoreWidth->integer );
}

/*
** RB_SurfaceLightningBolt
*/
static void RB_SurfaceLightningBolt( void ) {
	refEntity_t *e;
	int len;
	vec3_t right;
	vec3_t vec;
	vec3_t start, end;
	vec3_t v1, v2;
	int i;

	e = &backEnd.currentEntity->e;

	VectorCopy( e->oldorigin, end );
	VectorCopy( e->origin, start );

	// compute variables
	VectorSubtract( end, start, vec );
	len = VectorNormalize( vec );

	// compute side vector
	VectorSubtract( start, backEnd.viewParms.or.origin, v1 );
	VectorNormalize( v1 );
	VectorSubtract( end, backEnd.viewParms.or.origin, v2 );
	VectorNormalize( v2 );
	CrossProduct( v1, v2, right );
	VectorNormalize( right );

	for ( i = 0 ; i < 4 ; i++ ) {
		vec3_t temp;

		DoRailCore( start, end, right, len, 8 );
		RotatePointAroundVector( temp, vec, right, 45 );
		VectorCopy( temp, right );
	}
}

/*
** VectorArrayNormalize
*
* The inputs to this routing seem to always be close to length = 1.0 (about 0.6 to 2.0)
* This means that we don't have to worry about zero length or enormously long vectors.
*/
static void VectorArrayNormalize( vec4_t *normals, unsigned int count ) {
//    assert(count);

#if idppc
	{
		register float half = 0.5;
		register float one  = 1.0;
		float *components = (float *)normals;

		// Vanilla PPC code, but since PPC has a reciprocal square root estimate instruction,
		// runs *much* faster than calling sqrt().  We'll use a single Newton-Raphson
		// refinement step to get a little more precision.  This seems to yeild results
		// that are correct to 3 decimal places and usually correct to at least 4 (sometimes 5).
		// (That is, for the given input range of about 0.6 to 2.0).
		do {
			float x, y, z;
			float B, y0, y1;

			x = components[0];
			y = components[1];
			z = components[2];
			components += 4;
			B = x * x + y * y + z * z;

#ifdef __GNUC__
			asm ( "frsqrte %0,%1" : "=f" ( y0 ) : "f" ( B ) );
#else
			y0 = __frsqrte( B );
#endif
			y1 = y0 + half * y0 * ( one - B * y0 * y0 );

			x = x * y1;
			y = y * y1;
			components[-4] = x;
			z = z * y1;
			components[-3] = y;
			components[-2] = z;
		} while ( count-- );
	}
#else // No assembly version for this architecture, or C_ONLY defined
	  // given the input, it's safe to call VectorNormalizeFast
	while ( count-- ) {
		VectorNormalizeFast( normals[0] );
		normals++;
	}
#endif

}



/*
** LerpMeshVertexes
*/
#if idppc_altivec
static void LerpMeshVertexes_altivec(md3Surface_t *surf, float backlerp)
{
	short	*oldXyz, *newXyz, *oldNormals, *newNormals;
	float	*outXyz, *outNormal;
	float	oldXyzScale QALIGN(16);
	float   newXyzScale QALIGN(16);
	float	oldNormalScale QALIGN(16);
	float newNormalScale QALIGN(16);
	int		vertNum;
	unsigned lat, lng;
	int		numVerts;

	outXyz = tess.xyz[tess.numVertexes];
	outNormal = tess.normal[tess.numVertexes];

	newXyz = (short *)((byte *)surf + surf->ofsXyzNormals)
		+ (backEnd.currentEntity->e.frame * surf->numVerts * 4);
	newNormals = newXyz + 3;

	newXyzScale = MD3_XYZ_SCALE * (1.0 - backlerp);
	newNormalScale = 1.0 - backlerp;

	numVerts = surf->numVerts;

	if ( backlerp == 0 ) {
		vector signed short newNormalsVec0;
		vector signed short newNormalsVec1;
		vector signed int newNormalsIntVec;
		vector float newNormalsFloatVec;
		vector float newXyzScaleVec;
		vector unsigned char newNormalsLoadPermute;
		vector unsigned char newNormalsStorePermute;
		vector float zero;
		
		newNormalsStorePermute = vec_lvsl(0,(float *)&newXyzScaleVec);
		newXyzScaleVec = *(vector float *)&newXyzScale;
		newXyzScaleVec = vec_perm(newXyzScaleVec,newXyzScaleVec,newNormalsStorePermute);
		newXyzScaleVec = vec_splat(newXyzScaleVec,0);		
		newNormalsLoadPermute = vec_lvsl(0,newXyz);
		newNormalsStorePermute = vec_lvsr(0,outXyz);
		zero = (vector float)vec_splat_s8(0);
		//
		// just copy the vertexes
		//
		for (vertNum=0 ; vertNum < numVerts ; vertNum++,
			newXyz += 4, newNormals += 4,
			outXyz += 4, outNormal += 4) 
		{
			newNormalsLoadPermute = vec_lvsl(0,newXyz);
			newNormalsStorePermute = vec_lvsr(0,outXyz);
			newNormalsVec0 = vec_ld(0,newXyz);
			newNormalsVec1 = vec_ld(16,newXyz);
			newNormalsVec0 = vec_perm(newNormalsVec0,newNormalsVec1,newNormalsLoadPermute);
			newNormalsIntVec = vec_unpackh(newNormalsVec0);
			newNormalsFloatVec = vec_ctf(newNormalsIntVec,0);
			newNormalsFloatVec = vec_madd(newNormalsFloatVec,newXyzScaleVec,zero);
			newNormalsFloatVec = vec_perm(newNormalsFloatVec,newNormalsFloatVec,newNormalsStorePermute);
			//outXyz[0] = newXyz[0] * newXyzScale;
			//outXyz[1] = newXyz[1] * newXyzScale;
			//outXyz[2] = newXyz[2] * newXyzScale;

			lat = ( newNormals[0] >> 8 ) & 0xff;
			lng = ( newNormals[0] & 0xff );
			lat *= (FUNCTABLE_SIZE/256);
			lng *= (FUNCTABLE_SIZE/256);

			// decode X as cos( lat ) * sin( long )
			// decode Y as sin( lat ) * sin( long )
			// decode Z as cos( long )

			outNormal[0] = tr.sinTable[(lat+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK] * tr.sinTable[lng];
			outNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
			outNormal[2] = tr.sinTable[(lng+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK];

			vec_ste(newNormalsFloatVec,0,outXyz);
			vec_ste(newNormalsFloatVec,4,outXyz);
			vec_ste(newNormalsFloatVec,8,outXyz);
		}
	} else {
		//
		// interpolate and copy the vertex and normal
		//
		oldXyz = (short *)((byte *)surf + surf->ofsXyzNormals)
			+ (backEnd.currentEntity->e.oldframe * surf->numVerts * 4);
		oldNormals = oldXyz + 3;

		oldXyzScale = MD3_XYZ_SCALE * backlerp;
		oldNormalScale = backlerp;

		for (vertNum=0 ; vertNum < numVerts ; vertNum++,
			oldXyz += 4, newXyz += 4, oldNormals += 4, newNormals += 4,
			outXyz += 4, outNormal += 4) 
		{
			vec3_t uncompressedOldNormal, uncompressedNewNormal;

			// interpolate the xyz
			outXyz[0] = oldXyz[0] * oldXyzScale + newXyz[0] * newXyzScale;
			outXyz[1] = oldXyz[1] * oldXyzScale + newXyz[1] * newXyzScale;
			outXyz[2] = oldXyz[2] * oldXyzScale + newXyz[2] * newXyzScale;

			// FIXME: interpolate lat/long instead?
			lat = ( newNormals[0] >> 8 ) & 0xff;
			lng = ( newNormals[0] & 0xff );
			lat *= 4;
			lng *= 4;
			uncompressedNewNormal[0] = tr.sinTable[(lat+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK] * tr.sinTable[lng];
			uncompressedNewNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
			uncompressedNewNormal[2] = tr.sinTable[(lng+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK];

			lat = ( oldNormals[0] >> 8 ) & 0xff;
			lng = ( oldNormals[0] & 0xff );
			lat *= 4;
			lng *= 4;

			uncompressedOldNormal[0] = tr.sinTable[(lat+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK] * tr.sinTable[lng];
			uncompressedOldNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
			uncompressedOldNormal[2] = tr.sinTable[(lng+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK];

			outNormal[0] = uncompressedOldNormal[0] * oldNormalScale + uncompressedNewNormal[0] * newNormalScale;
			outNormal[1] = uncompressedOldNormal[1] * oldNormalScale + uncompressedNewNormal[1] * newNormalScale;
			outNormal[2] = uncompressedOldNormal[2] * oldNormalScale + uncompressedNewNormal[2] * newNormalScale;

//			VectorNormalize (outNormal);
		}
    	VectorArrayNormalize((vec4_t *)tess.normal[tess.numVertexes], numVerts);
   	}
}
#endif

static void LerpMeshVertexes_scalar(md3Surface_t *surf, float backlerp)
{
	short	*oldXyz, *newXyz, *oldNormals, *newNormals;
	float	*outXyz, *outNormal;
	float	oldXyzScale, newXyzScale;
	float	oldNormalScale, newNormalScale;
	int		vertNum;
	unsigned lat, lng;
	int		numVerts;

	outXyz = tess.xyz[tess.numVertexes];
	outNormal = tess.normal[tess.numVertexes];

	newXyz = (short *)((byte *)surf + surf->ofsXyzNormals)
		+ (backEnd.currentEntity->e.frame * surf->numVerts * 4);
	newNormals = newXyz + 3;

	newXyzScale = MD3_XYZ_SCALE * (1.0 - backlerp);
	newNormalScale = 1.0 - backlerp;

	numVerts = surf->numVerts;

	if ( backlerp == 0 ) {
		//
		// just copy the vertexes
		//
		for (vertNum=0 ; vertNum < numVerts ; vertNum++,
			newXyz += 4, newNormals += 4,
			outXyz += 4, outNormal += 4) 
		{

			outXyz[0] = newXyz[0] * newXyzScale;
			outXyz[1] = newXyz[1] * newXyzScale;
			outXyz[2] = newXyz[2] * newXyzScale;

			lat = ( newNormals[0] >> 8 ) & 0xff;
			lng = ( newNormals[0] & 0xff );
			lat *= (FUNCTABLE_SIZE/256);
			lng *= (FUNCTABLE_SIZE/256);

			// decode X as cos( lat ) * sin( long )
			// decode Y as sin( lat ) * sin( long )
			// decode Z as cos( long )

			outNormal[0] = tr.sinTable[(lat+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK] * tr.sinTable[lng];
			outNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
			outNormal[2] = tr.sinTable[(lng+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK];
		}
	} else {
		//
		// interpolate and copy the vertex and normal
		//
		oldXyz = (short *)((byte *)surf + surf->ofsXyzNormals)
			+ (backEnd.currentEntity->e.oldframe * surf->numVerts * 4);
		oldNormals = oldXyz + 3;

		oldXyzScale = MD3_XYZ_SCALE * backlerp;
		oldNormalScale = backlerp;

		for (vertNum=0 ; vertNum < numVerts ; vertNum++,
			oldXyz += 4, newXyz += 4, oldNormals += 4, newNormals += 4,
			outXyz += 4, outNormal += 4) 
		{
			vec3_t uncompressedOldNormal, uncompressedNewNormal;

			// interpolate the xyz
			outXyz[0] = oldXyz[0] * oldXyzScale + newXyz[0] * newXyzScale;
			outXyz[1] = oldXyz[1] * oldXyzScale + newXyz[1] * newXyzScale;
			outXyz[2] = oldXyz[2] * oldXyzScale + newXyz[2] * newXyzScale;

			// FIXME: interpolate lat/long instead?
			lat = ( newNormals[0] >> 8 ) & 0xff;
			lng = ( newNormals[0] & 0xff );
			lat *= 4;
			lng *= 4;
			uncompressedNewNormal[0] = tr.sinTable[(lat+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK] * tr.sinTable[lng];
			uncompressedNewNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
			uncompressedNewNormal[2] = tr.sinTable[(lng+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK];

			lat = ( oldNormals[0] >> 8 ) & 0xff;
			lng = ( oldNormals[0] & 0xff );
			lat *= 4;
			lng *= 4;

			uncompressedOldNormal[0] = tr.sinTable[(lat+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK] * tr.sinTable[lng];
			uncompressedOldNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
			uncompressedOldNormal[2] = tr.sinTable[(lng+(FUNCTABLE_SIZE/4))&FUNCTABLE_MASK];

			outNormal[0] = uncompressedOldNormal[0] * oldNormalScale + uncompressedNewNormal[0] * newNormalScale;
			outNormal[1] = uncompressedOldNormal[1] * oldNormalScale + uncompressedNewNormal[1] * newNormalScale;
			outNormal[2] = uncompressedOldNormal[2] * oldNormalScale + uncompressedNewNormal[2] * newNormalScale;

//			VectorNormalize (outNormal);
		}
    	VectorArrayNormalize((vec4_t *)tess.normal[tess.numVertexes], numVerts);
   	}
}

static void LerpMeshVertexes(md3Surface_t *surf, float backlerp)
{
#if idppc_altivec
	if (com_altivec->integer) {
		// must be in a seperate function or G3 systems will crash.
		LerpMeshVertexes_altivec( surf, backlerp );
		return;
	}
#endif // idppc_altivec
	LerpMeshVertexes_scalar( surf, backlerp );
}


/*
=============
RB_SurfaceMesh
=============
*/
static void RB_SurfaceMesh( md3Surface_t *surface ) {
	int j;
	float backlerp;
	int             *triangles;
	float           *texCoords;
	int indexes;
	int Bob, Doug;
	int numVerts;

	// RF, check for REFLAG_HANDONLY
	if ( backEnd.currentEntity->e.reFlags & REFLAG_ONLYHAND ) {
		if ( !strstr( surface->name, "hand" ) ) {
			return;
		}
	}

	if (  backEnd.currentEntity->e.oldframe == backEnd.currentEntity->e.frame ) {
		backlerp = 0;
	} else  {
		backlerp = backEnd.currentEntity->e.backlerp;
	}

	RB_CHECKOVERFLOW( surface->numVerts, surface->numTriangles * 3 );

	LerpMeshVertexes( surface, backlerp );

	triangles = ( int * )( (byte *)surface + surface->ofsTriangles );
	indexes = surface->numTriangles * 3;
	Bob = tess.numIndexes;
	Doug = tess.numVertexes;
	for ( j = 0 ; j < indexes ; j++ ) {
		tess.indexes[Bob + j] = Doug + triangles[j];
	}
	tess.numIndexes += indexes;

	texCoords = ( float * )( (byte *)surface + surface->ofsSt );

	numVerts = surface->numVerts;
	for ( j = 0; j < numVerts; j++ ) {
		tess.texCoords[Doug + j][0][0] = texCoords[j * 2 + 0];
		tess.texCoords[Doug + j][0][1] = texCoords[j * 2 + 1];
		// FIXME: fill in lightmapST for completeness?
	}

	tess.numVertexes += surface->numVerts;

}

/*
** R_LatLongToNormal
*/
void R_LatLongToNormal( vec3_t outNormal, short latLong ) {
	unsigned lat, lng;

	lat = ( latLong >> 8 ) & 0xff;
	lng = ( latLong & 0xff );
	lat *= ( FUNCTABLE_SIZE / 256 );
	lng *= ( FUNCTABLE_SIZE / 256 );

	// decode X as cos( lat ) * sin( long )
	// decode Y as sin( lat ) * sin( long )
	// decode Z as cos( long )

	outNormal[0] = tr.sinTable[( lat + ( FUNCTABLE_SIZE / 4 ) ) & FUNCTABLE_MASK] * tr.sinTable[lng];
	outNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
	outNormal[2] = tr.sinTable[( lng + ( FUNCTABLE_SIZE / 4 ) ) & FUNCTABLE_MASK];
}

// Ridah
/*
** LerpCMeshVertexes
*/
static void LerpCMeshVertexes( mdcSurface_t *surf, float backlerp ) {
	short   *oldXyz, *newXyz, *oldNormals, *newNormals;
	float   *outXyz, *outNormal;
	float oldXyzScale, newXyzScale;
	float oldNormalScale, newNormalScale;
	int vertNum;
	unsigned lat, lng;
	int numVerts;

	int oldBase, newBase;
	short   *oldComp = NULL, *newComp = NULL; // TTimo: init
	mdcXyzCompressed_t *oldXyzComp = NULL, *newXyzComp = NULL; // TTimo: init
	vec3_t oldOfsVec, newOfsVec;

	qboolean hasComp;

	outXyz = tess.xyz[tess.numVertexes];
	outNormal = tess.normal[tess.numVertexes];

	newBase = (int)*( ( short * )( (byte *)surf + surf->ofsFrameBaseFrames ) + backEnd.currentEntity->e.frame );
	newXyz = ( short * )( (byte *)surf + surf->ofsXyzNormals )
			 + ( newBase * surf->numVerts * 4 );
	newNormals = newXyz + 3;

	hasComp = ( surf->numCompFrames > 0 );
	if ( hasComp ) {
		newComp = ( ( short * )( (byte *)surf + surf->ofsFrameCompFrames ) + backEnd.currentEntity->e.frame );
		if ( *newComp >= 0 ) {
			newXyzComp = ( mdcXyzCompressed_t * )( (byte *)surf + surf->ofsXyzCompressed )
						 + ( *newComp * surf->numVerts );
		}
	}

	newXyzScale = MD3_XYZ_SCALE * ( 1.0 - backlerp );
	newNormalScale = 1.0 - backlerp;

	numVerts = surf->numVerts;

	if ( backlerp == 0 ) {
		//
		// just copy the vertexes
		//
		for ( vertNum = 0 ; vertNum < numVerts ; vertNum++,
			  newXyz += 4, newNormals += 4,
			  outXyz += 4, outNormal += 4 )
		{

			outXyz[0] = newXyz[0] * newXyzScale;
			outXyz[1] = newXyz[1] * newXyzScale;
			outXyz[2] = newXyz[2] * newXyzScale;

			// add the compressed ofsVec
			if ( hasComp && *newComp >= 0 ) {
				R_MDC_DecodeXyzCompressed( newXyzComp->ofsVec, newOfsVec, outNormal );
				newXyzComp++;
				VectorAdd( outXyz, newOfsVec, outXyz );
			} else {
				lat = ( newNormals[0] >> 8 ) & 0xff;
				lng = ( newNormals[0] & 0xff );
				lat *= 4;
				lng *= 4;

				outNormal[0] = tr.sinTable[( lat + ( FUNCTABLE_SIZE / 4 ) ) & FUNCTABLE_MASK] * tr.sinTable[lng];
				outNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
				outNormal[2] = tr.sinTable[( lng + ( FUNCTABLE_SIZE / 4 ) ) & FUNCTABLE_MASK];
			}
		}
	} else {
		//
		// interpolate and copy the vertex and normal
		//
		oldBase = (int)*( ( short * )( (byte *)surf + surf->ofsFrameBaseFrames ) + backEnd.currentEntity->e.oldframe );
		oldXyz = ( short * )( (byte *)surf + surf->ofsXyzNormals )
				 + ( oldBase * surf->numVerts * 4 );
		oldNormals = oldXyz + 3;

		if ( hasComp ) {
			oldComp = ( ( short * )( (byte *)surf + surf->ofsFrameCompFrames ) + backEnd.currentEntity->e.oldframe );
			if ( *oldComp >= 0 ) {
				oldXyzComp = ( mdcXyzCompressed_t * )( (byte *)surf + surf->ofsXyzCompressed )
							 + ( *oldComp * surf->numVerts );
			}
		}

		oldXyzScale = MD3_XYZ_SCALE * backlerp;
		oldNormalScale = backlerp;

		for ( vertNum = 0 ; vertNum < numVerts ; vertNum++,
			  oldXyz += 4, newXyz += 4, oldNormals += 4, newNormals += 4,
			  outXyz += 4, outNormal += 4 )
		{
			vec3_t uncompressedOldNormal, uncompressedNewNormal;

			// interpolate the xyz
			outXyz[0] = oldXyz[0] * oldXyzScale + newXyz[0] * newXyzScale;
			outXyz[1] = oldXyz[1] * oldXyzScale + newXyz[1] * newXyzScale;
			outXyz[2] = oldXyz[2] * oldXyzScale + newXyz[2] * newXyzScale;

			// add the compressed ofsVec
			if ( hasComp && *newComp >= 0 ) {
				R_MDC_DecodeXyzCompressed( newXyzComp->ofsVec, newOfsVec, uncompressedNewNormal );
				newXyzComp++;
				VectorMA( outXyz, 1.0 - backlerp, newOfsVec, outXyz );
			} else {
				lat = ( newNormals[0] >> 8 ) & 0xff;
				lng = ( newNormals[0] & 0xff );
				lat *= 4;
				lng *= 4;

				uncompressedNewNormal[0] = tr.sinTable[( lat + ( FUNCTABLE_SIZE / 4 ) ) & FUNCTABLE_MASK] * tr.sinTable[lng];
				uncompressedNewNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
				uncompressedNewNormal[2] = tr.sinTable[( lng + ( FUNCTABLE_SIZE / 4 ) ) & FUNCTABLE_MASK];
			}

			if ( hasComp && *oldComp >= 0 ) {
				R_MDC_DecodeXyzCompressed( oldXyzComp->ofsVec, oldOfsVec, uncompressedOldNormal );
				oldXyzComp++;
				VectorMA( outXyz, backlerp, oldOfsVec, outXyz );
			} else {
				lat = ( oldNormals[0] >> 8 ) & 0xff;
				lng = ( oldNormals[0] & 0xff );
				lat *= 4;
				lng *= 4;

				uncompressedOldNormal[0] = tr.sinTable[( lat + ( FUNCTABLE_SIZE / 4 ) ) & FUNCTABLE_MASK] * tr.sinTable[lng];
				uncompressedOldNormal[1] = tr.sinTable[lat] * tr.sinTable[lng];
				uncompressedOldNormal[2] = tr.sinTable[( lng + ( FUNCTABLE_SIZE / 4 ) ) & FUNCTABLE_MASK];
			}

			outNormal[0] = uncompressedOldNormal[0] * oldNormalScale + uncompressedNewNormal[0] * newNormalScale;
			outNormal[1] = uncompressedOldNormal[1] * oldNormalScale + uncompressedNewNormal[1] * newNormalScale;
			outNormal[2] = uncompressedOldNormal[2] * oldNormalScale + uncompressedNewNormal[2] * newNormalScale;

			VectorNormalize( outNormal );
		}
	}
}

/*
=============
RB_SurfaceCMesh
=============
*/
void RB_SurfaceCMesh( mdcSurface_t *surface ) {
	int j;
	float backlerp;
	int             *triangles;
	float           *texCoords;
	int indexes;
	int Bob, Doug;
	int numVerts;

	// RF, check for REFLAG_HANDONLY
	if ( backEnd.currentEntity->e.reFlags & REFLAG_ONLYHAND ) {
		if ( !strstr( surface->name, "hand" ) ) {
			return;
		}
	}

	if (  backEnd.currentEntity->e.oldframe == backEnd.currentEntity->e.frame ) {
		backlerp = 0;
	} else  {
		backlerp = backEnd.currentEntity->e.backlerp;
	}

	RB_CHECKOVERFLOW( surface->numVerts, surface->numTriangles * 3 );

	LerpCMeshVertexes( surface, backlerp );

	triangles = ( int * )( (byte *)surface + surface->ofsTriangles );
	indexes = surface->numTriangles * 3;
	Bob = tess.numIndexes;
	Doug = tess.numVertexes;
	for ( j = 0 ; j < indexes ; j++ ) {
		tess.indexes[Bob + j] = Doug + triangles[j];
	}
	tess.numIndexes += indexes;

	texCoords = ( float * )( (byte *)surface + surface->ofsSt );

	numVerts = surface->numVerts;
	for ( j = 0; j < numVerts; j++ ) {
		tess.texCoords[Doug + j][0][0] = texCoords[j * 2 + 0];
		tess.texCoords[Doug + j][0][1] = texCoords[j * 2 + 1];
		// FIXME: fill in lightmapST for completeness?
	}

	tess.numVertexes += surface->numVerts;
}
// done.

/*
==============
RB_SurfaceFace
==============
*/
void RB_SurfaceFace( srfSurfaceFace_t *surf ) {
	int i;
	unsigned	*indices;
	glIndex_t	*tessIndexes;
	float       *v;
	float       *normal;
	int ndx;
	int Bob;
	int numPoints;
	int dlightBits;

	RB_CHECKOVERFLOW( surf->numPoints, surf->numIndices );

	dlightBits = surf->dlightBits;
	tess.dlightBits |= dlightBits;

	indices = ( unsigned * )( ( ( char  * ) surf ) + surf->ofsIndices );

	Bob = tess.numVertexes;
	tessIndexes = tess.indexes + tess.numIndexes;
	for ( i = surf->numIndices - 1 ; i >= 0  ; i-- ) {
		tessIndexes[i] = indices[i] + Bob;
	}

	tess.numIndexes += surf->numIndices;

	numPoints = surf->numPoints;

	if ( tess.shader->needsNormal ) {
		normal = surf->plane.normal;
		for ( i = 0, ndx = tess.numVertexes; i < numPoints; i++, ndx++ ) {
			VectorCopy( normal, tess.normal[ndx] );
		}
	}

	for ( i = 0, v = surf->points[0], ndx = tess.numVertexes; i < numPoints; i++, v += VERTEXSIZE, ndx++ ) {
		VectorCopy( v, tess.xyz[ndx] );
		tess.texCoords[ndx][0][0] = v[3];
		tess.texCoords[ndx][0][1] = v[4];
		tess.texCoords[ndx][1][0] = v[5];
		tess.texCoords[ndx][1][1] = v[6];
		*( unsigned int * ) &tess.vertexColors[ndx] = *( unsigned int * ) &v[7];
		tess.vertexDlightBits[ndx] = dlightBits;
	}


	tess.numVertexes += surf->numPoints;
}


static float    LodErrorForVolume( vec3_t local, float radius ) {
	vec3_t world;
	float d;

	// never let it go negative
	if ( r_lodCurveError->value < 0 ) {
		return 0;
	}

	world[0] = local[0] * backEnd.or.axis[0][0] + local[1] * backEnd.or.axis[1][0] +
			   local[2] * backEnd.or.axis[2][0] + backEnd.or.origin[0];
	world[1] = local[0] * backEnd.or.axis[0][1] + local[1] * backEnd.or.axis[1][1] +
			   local[2] * backEnd.or.axis[2][1] + backEnd.or.origin[1];
	world[2] = local[0] * backEnd.or.axis[0][2] + local[1] * backEnd.or.axis[1][2] +
			   local[2] * backEnd.or.axis[2][2] + backEnd.or.origin[2];

	VectorSubtract( world, backEnd.viewParms.or.origin, world );
	d = DotProduct( world, backEnd.viewParms.or.axis[0] );

	if ( d < 0 ) {
		d = -d;
	}
	d -= radius;
	if ( d < 1 ) {
		d = 1;
	}

	return r_lodCurveError->value / d;
}

/*
=============
RB_SurfaceGrid

Just copy the grid of points and triangulate
=============
*/
static void RB_SurfaceGrid( srfGridMesh_t *cv ) {
	int i, j;
	float   *xyz;
	float   *texCoords;
	float   *normal;
	unsigned char *color;
	drawVert_t  *dv;
	int rows, irows, vrows;
	int used;
	int widthTable[MAX_GRID_SIZE];
	int heightTable[MAX_GRID_SIZE];
	float lodError;
	int lodWidth, lodHeight;
	int numVertexes;
	int dlightBits;
	int     *vDlightBits;
	qboolean needsNormal;

	dlightBits = cv->dlightBits;
	tess.dlightBits |= dlightBits;

	// determine the allowable discrepance
	lodError = LodErrorForVolume( cv->lodOrigin, cv->lodRadius );

	// determine which rows and columns of the subdivision
	// we are actually going to use
	widthTable[0] = 0;
	lodWidth = 1;
	for ( i = 1 ; i < cv->width - 1 ; i++ ) {
		if ( cv->widthLodError[i] <= lodError ) {
			widthTable[lodWidth] = i;
			lodWidth++;
		}
	}
	widthTable[lodWidth] = cv->width - 1;
	lodWidth++;

	heightTable[0] = 0;
	lodHeight = 1;
	for ( i = 1 ; i < cv->height - 1 ; i++ ) {
		if ( cv->heightLodError[i] <= lodError ) {
			heightTable[lodHeight] = i;
			lodHeight++;
		}
	}
	heightTable[lodHeight] = cv->height - 1;
	lodHeight++;


	// very large grids may have more points or indexes than can be fit
	// in the tess structure, so we may have to issue it in multiple passes

	used = 0;
	while ( used < lodHeight - 1 ) {
		// see how many rows of both verts and indexes we can add without overflowing
		do {
			vrows = ( SHADER_MAX_VERTEXES - tess.numVertexes ) / lodWidth;
			irows = ( SHADER_MAX_INDEXES - tess.numIndexes ) / ( lodWidth * 6 );

			// if we don't have enough space for at least one strip, flush the buffer
			if ( vrows < 2 || irows < 1 ) {
				RB_EndSurface();
				RB_BeginSurface( tess.shader, tess.fogNum );
			} else {
				break;
			}
		} while ( 1 );

		rows = irows;
		if ( vrows < irows + 1 ) {
			rows = vrows - 1;
		}
		if ( used + rows > lodHeight ) {
			rows = lodHeight - used;
		}

		numVertexes = tess.numVertexes;

		xyz = tess.xyz[numVertexes];
		normal = tess.normal[numVertexes];
		texCoords = tess.texCoords[numVertexes][0];
		color = ( unsigned char * ) &tess.vertexColors[numVertexes];
		vDlightBits = &tess.vertexDlightBits[numVertexes];
		needsNormal = tess.shader->needsNormal;

		for ( i = 0 ; i < rows ; i++ ) {
			for ( j = 0 ; j < lodWidth ; j++ ) {
				dv = cv->verts + heightTable[ used + i ] * cv->width
					 + widthTable[ j ];

				xyz[0] = dv->xyz[0];
				xyz[1] = dv->xyz[1];
				xyz[2] = dv->xyz[2];
				texCoords[0] = dv->st[0];
				texCoords[1] = dv->st[1];
				texCoords[2] = dv->lightmap[0];
				texCoords[3] = dv->lightmap[1];
				if ( needsNormal ) {
					normal[0] = dv->normal[0];
					normal[1] = dv->normal[1];
					normal[2] = dv->normal[2];
				}
				*( unsigned int * ) color = *( unsigned int * ) dv->color;
				*vDlightBits++ = dlightBits;
				xyz += 4;
				normal += 4;
				texCoords += 4;
				color += 4;
			}
		}


		// add the indexes
		{
			int numIndexes;
			int w, h;

			h = rows - 1;
			w = lodWidth - 1;
			numIndexes = tess.numIndexes;
			for ( i = 0 ; i < h ; i++ ) {
				for ( j = 0 ; j < w ; j++ ) {
					int v1, v2, v3, v4;

					// vertex order to be reckognized as tristrips
					v1 = numVertexes + i * lodWidth + j + 1;
					v2 = v1 - 1;
					v3 = v2 + lodWidth;
					v4 = v3 + 1;

					tess.indexes[numIndexes] = v2;
					tess.indexes[numIndexes + 1] = v3;
					tess.indexes[numIndexes + 2] = v1;

					tess.indexes[numIndexes + 3] = v1;
					tess.indexes[numIndexes + 4] = v3;
					tess.indexes[numIndexes + 5] = v4;
					numIndexes += 6;
				}
			}

			tess.numIndexes = numIndexes;
		}

		tess.numVertexes += rows * lodWidth;

		used += rows - 1;
	}
}


/*
===========================================================================

NULL MODEL

===========================================================================
*/

/*
===================
RB_SurfaceAxis

Draws x/y/z lines from the origin for orientation debugging
===================
*/
static void RB_SurfaceAxis( void ) {
	GL_Bind( tr.whiteImage );
	GL_State( GLS_DEFAULT );
	qglLineWidth( 3 );
#ifdef USE_OPENGLES
	GLfloat col[] = {
	  1,0,0, 1,
	  1,0,0, 1,
	  0,1,0, 1,
	  0,1,0, 1,
	  0,0,1, 1,
	  0,0,1, 1
	 };
	 GLfloat vtx[] = {
	  0,0,0,
	  16,0,0,
	  0,0,0,
	  0,16,0,
	  0,0,0,
	  0,0,16
	 };
	GLboolean text = qglIsEnabled(GL_TEXTURE_COORD_ARRAY);
	GLboolean glcol = qglIsEnabled(GL_COLOR_ARRAY);
	if (text)
		qglDisableClientState( GL_TEXTURE_COORD_ARRAY );
	if (!glcol)
		qglEnableClientState( GL_COLOR_ARRAY);
	qglColorPointer( 4, GL_UNSIGNED_BYTE, 0, col );
	qglVertexPointer (3, GL_FLOAT, 0, vtx);
	qglDrawArrays(GL_LINES, 0, 6);
	if (text)
		qglEnableClientState( GL_TEXTURE_COORD_ARRAY );
	if (!glcol)
		qglDisableClientState( GL_COLOR_ARRAY);
#else
	qglBegin( GL_LINES );
	qglColor3f( 1,0,0 );
	qglVertex3f( 0,0,0 );
	qglVertex3f( 16,0,0 );
	qglColor3f( 0,1,0 );
	qglVertex3f( 0,0,0 );
	qglVertex3f( 0,16,0 );
	qglColor3f( 0,0,1 );
	qglVertex3f( 0,0,0 );
	qglVertex3f( 0,0,16 );
	qglEnd();
#endif
	qglLineWidth( 1 );
}

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

/*
====================
RB_SurfaceEntity

Entities that have a single procedurally generated surface
====================
*/
static void RB_SurfaceEntity( surfaceType_t *surfType ) {
	switch ( backEnd.currentEntity->e.reType ) {
	case RT_SPLASH:
		RB_SurfaceSplash();
		break;
	case RT_SPRITE:
		RB_SurfaceSprite();
		break;
	case RT_BEAM:
		RB_SurfaceBeam();
		break;
	case RT_RAIL_CORE:
		RB_SurfaceRailCore();
		break;
	case RT_RAIL_RINGS:
		RB_SurfaceRailRings();
		break;
	case RT_LIGHTNING:
		RB_SurfaceLightningBolt();
		break;
	default:
		RB_SurfaceAxis();
		break;
	}
}

static void RB_SurfaceBad( surfaceType_t *surfType ) {
	ri.Printf( PRINT_ALL, "Bad surface tesselated.\n" );
}

static void RB_SurfaceFlare( srfFlare_t *surf ) {
	if (r_flares->integer)
		RB_AddFlare(surf, tess.fogNum, surf->origin, surf->color, 1.0f, surf->normal, 0, qtrue);
}

static void RB_SurfaceSkip( void *surf ) {
}


void( *rb_surfaceTable[SF_NUM_SURFACE_TYPES] ) ( void * ) = {
	( void( * ) ( void* ) )RB_SurfaceBad,          // SF_BAD,
	( void( * ) ( void* ) )RB_SurfaceSkip,         // SF_SKIP,
	( void( * ) ( void* ) )RB_SurfaceFace,         // SF_FACE,
	( void( * ) ( void* ) )RB_SurfaceGrid,         // SF_GRID,
	( void( * ) ( void* ) )RB_SurfaceTriangles,    // SF_TRIANGLES,
	( void( * ) ( void* ) )RB_SurfacePolychain,    // SF_POLY,
	( void( * ) ( void* ) )RB_SurfaceMesh,         // SF_MD3,
	( void( * ) ( void* ) )RB_SurfaceCMesh,        // SF_MDC,
	( void( * ) ( void* ) )RB_SurfaceAnim,         // SF_MDS,
	( void( * ) ( void* ) )RB_MDRSurfaceAnim,      // SF_MDR,
	( void( * ) ( void* ) )RB_IQMSurfaceAnim,      // SF_IQM,
	( void( * ) ( void* ) )RB_SurfaceFlare,        // SF_FLARE,
	( void( * ) ( void* ) )RB_SurfaceEntity        // SF_ENTITY
};
