ioef/q3map/surface.c

/*
===========================================================================
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 Foobar; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/

#include "qbsp.h"


mapDrawSurface_t	mapDrawSurfs[MAX_MAP_DRAW_SURFS];
int			numMapDrawSurfs;

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

DRAWSURF CONSTRUCTION

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

/*
=================
AllocDrawSurf
=================
*/
mapDrawSurface_t	*AllocDrawSurf( void ) {
	mapDrawSurface_t	*ds;

	if ( numMapDrawSurfs >= MAX_MAP_DRAW_SURFS ) {
		Error( "MAX_MAP_DRAW_SURFS");
	}
	ds = &mapDrawSurfs[ numMapDrawSurfs ];
	numMapDrawSurfs++;

	return ds;
}

/*
=================
DrawSurfaceForSide
=================
*/
#define	SNAP_FLOAT_TO_INT	8
#define	SNAP_INT_TO_FLOAT	(1.0/SNAP_FLOAT_TO_INT)

mapDrawSurface_t	*DrawSurfaceForSide( bspbrush_t *b, side_t *s, winding_t *w ) {
	mapDrawSurface_t	*ds;
	int					i, j;
	shaderInfo_t		*si;
	drawVert_t			*dv;
	float				mins[2], maxs[2];

	// brush primitive :
	// axis base
	vec3_t		texX,texY;
	vec_t		x,y;

	if ( w->numpoints > 64 ) {
		Error( "DrawSurfaceForSide: w->numpoints = %i", w->numpoints );
	}

	si = s->shaderInfo;

	ds = AllocDrawSurf();

	ds->shaderInfo = si;
	ds->mapBrush = b;
	ds->side = s;
	ds->fogNum = -1;
	ds->numVerts = w->numpoints;
	ds->verts = malloc( ds->numVerts * sizeof( *ds->verts ) );
	memset( ds->verts, 0, ds->numVerts * sizeof( *ds->verts ) );

	mins[0] = mins[1] = 99999;
	maxs[0] = maxs[1] = -99999;

	// compute s/t coordinates from brush primitive texture matrix
	// compute axis base
	ComputeAxisBase( mapplanes[s->planenum].normal, texX, texY );

	for ( j = 0 ; j < w->numpoints ; j++ ) {
		dv = ds->verts + j;

		// round the xyz to a given precision
		for ( i = 0 ; i < 3 ; i++ ) {
			dv->xyz[i] = SNAP_INT_TO_FLOAT * floor( w->p[j][i] * SNAP_FLOAT_TO_INT + 0.5 );
		}
	
		if (g_bBrushPrimit==BPRIMIT_OLDBRUSHES)
		{
			// calculate texture s/t
			dv->st[0] = s->vecs[0][3] + DotProduct( s->vecs[0],	dv->xyz );
			dv->st[1] = s->vecs[1][3] + DotProduct( s->vecs[1],	dv->xyz );
			dv->st[0] /= si->width;
			dv->st[1] /= si->height;
		} 
		else
		{
			// calculate texture s/t from brush primitive texture matrix
			x = DotProduct( dv->xyz, texX );
			y = DotProduct( dv->xyz, texY );
			dv->st[0]=s->texMat[0][0]*x+s->texMat[0][1]*y+s->texMat[0][2];
			dv->st[1]=s->texMat[1][0]*x+s->texMat[1][1]*y+s->texMat[1][2];
		}

		for ( i = 0 ; i < 2 ; i++ ) {
			if ( dv->st[i] < mins[i] ) {
				mins[i] = dv->st[i];
			}
			if ( dv->st[i] > maxs[i] ) {
				maxs[i] = dv->st[i];
			}
		}

		// copy normal
		VectorCopy ( mapplanes[s->planenum].normal, dv->normal );
	}

	// adjust the texture coordinates to be as close to 0 as possible
	if ( !si->globalTexture ) {
		mins[0] = floor( mins[0] );
		mins[1] = floor( mins[1] );
		for ( i = 0 ; i < w->numpoints ; i++ ) {
			dv = ds->verts + i;
			dv->st[0] -= mins[0];
			dv->st[1] -= mins[1];
		}
	}

	return ds;
}


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




typedef struct {
	int				planenum;
	shaderInfo_t	*shaderInfo;
	int				count;
} sideRef_t;

#define	MAX_SIDE_REFS	MAX_MAP_PLANES

sideRef_t	sideRefs[MAX_SIDE_REFS];
int			numSideRefs;

void AddSideRef( side_t *side ) {
	int		i;

	for ( i = 0 ; i < numSideRefs ; i++ ) {
		if ( side->planenum == sideRefs[i].planenum
			&& side->shaderInfo == sideRefs[i].shaderInfo ) {
			sideRefs[i].count++;
			return;
		}
	}

	if ( numSideRefs == MAX_SIDE_REFS ) {
		Error( "MAX_SIDE_REFS" );
	}

	sideRefs[i].planenum = side->planenum;
	sideRefs[i].shaderInfo = side->shaderInfo;
	sideRefs[i].count++;
	numSideRefs++;
}


/*
=====================
MergeSides

=====================
*/
void MergeSides( entity_t *e, tree_t *tree ) {
	int				i;

	qprintf( "----- MergeSides -----\n");

	for ( i = e->firstDrawSurf ; i < numMapDrawSurfs ; i++ ) {
//			AddSideRef( side );
	}

	qprintf( "%5i siderefs\n", numSideRefs );
}

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

/*
===================
SubdivideDrawSurf
===================
*/
void SubdivideDrawSurf( mapDrawSurface_t *ds, winding_t *w, float subdivisions ) {
	int				i;
	int				axis;
	vec3_t			bounds[2];
	const float		epsilon = 0.1;
	int				subFloor, subCeil;
	winding_t		*frontWinding, *backWinding;
	mapDrawSurface_t	*newds;

	if ( !w ) {
		return;
	}
	if ( w->numpoints < 3 ) {
		Error( "SubdivideDrawSurf: Bad w->numpoints" );
	}

	ClearBounds( bounds[0], bounds[1] );
	for ( i = 0 ; i < w->numpoints ; i++ ) {
		AddPointToBounds( w->p[i], bounds[0], bounds[1] );
	}

	for ( axis = 0 ; axis < 3 ; axis++ ) {
		vec3_t planePoint = { 0, 0, 0 };
		vec3_t planeNormal = { 0, 0, 0 };
		float d;

		subFloor = floor( bounds[0][axis]  / subdivisions ) * subdivisions;
		subCeil = ceil( bounds[1][axis] / subdivisions ) * subdivisions;

		planePoint[axis] = subFloor + subdivisions;
		planeNormal[axis] = -1;

		d = DotProduct( planePoint, planeNormal );

		// subdivide if necessary
		if ( subCeil - subFloor > subdivisions ) {
			// gotta clip polygon into two polygons
			ClipWindingEpsilon( w, planeNormal, d, epsilon, &frontWinding, &backWinding );

			// the clip may not produce two polygons if it was epsilon close
			if ( !frontWinding ) {
				w = backWinding;
			} else if ( !backWinding ) {
				w = frontWinding;
			} else {
				SubdivideDrawSurf( ds, frontWinding, subdivisions );
				SubdivideDrawSurf( ds, backWinding, subdivisions );

				return;
			}
		}
	}

	// emit this polygon
	newds = DrawSurfaceForSide( ds->mapBrush, ds->side, w );
	newds->fogNum = ds->fogNum;
}


/*
=====================
SubdivideDrawSurfs

Chop up surfaces that have subdivision attributes
=====================
*/
void SubdivideDrawSurfs( entity_t *e, tree_t *tree ) {
	int				i;
	mapDrawSurface_t	*ds;
	int				numBaseDrawSurfs;
	winding_t		*w;
	float			subdivision;
	shaderInfo_t	*si;

	qprintf( "----- SubdivideDrawSurfs -----\n");
	numBaseDrawSurfs = numMapDrawSurfs;
	for ( i = e->firstDrawSurf ; i < numBaseDrawSurfs ; i++ ) {
		ds = &mapDrawSurfs[i];

		// only subdivide brush sides, not patches or misc_models
		if ( !ds->side ) {
			continue;
		}

		// check subdivision for shader
		si = ds->side->shaderInfo;
		if ( !si ) {
			continue;
		}

		if (ds->shaderInfo->autosprite || si->autosprite) {
			continue;
		}

		subdivision = si->subdivisions;
		if ( !subdivision ) {
			continue;
		}

		w = WindingFromDrawSurf( ds );
		ds->numVerts = 0;		// remove this reference
		SubdivideDrawSurf( ds, w, subdivision );
	}

}


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

/*
====================
ClipSideIntoTree_r

Adds non-opaque leaf fragments to the convex hull
====================
*/
void ClipSideIntoTree_r( winding_t *w, side_t *side, node_t *node ) {
	plane_t			*plane;
	winding_t		*front, *back;

	if ( !w ) {
		return;
	}

	if ( node->planenum != PLANENUM_LEAF ) {
		if ( side->planenum == node->planenum ) {
			ClipSideIntoTree_r( w, side, node->children[0] );
			return;
		}
		if ( side->planenum == ( node->planenum ^ 1) ) {
			ClipSideIntoTree_r( w, side, node->children[1] );
			return;
		}

		plane = &mapplanes[ node->planenum ];
		ClipWindingEpsilon ( w, plane->normal, plane->dist,
				ON_EPSILON, &front, &back );
		FreeWinding( w );

		ClipSideIntoTree_r( front, side, node->children[0] );
		ClipSideIntoTree_r( back, side, node->children[1] );

		return;
	}

	// if opaque leaf, don't add
	if ( !node->opaque ) {
		AddWindingToConvexHull( w, &side->visibleHull, mapplanes[ side->planenum ].normal );
	}

	FreeWinding( w );
	return;
}


/*
=====================
ClipSidesIntoTree

Creates side->visibleHull for all visible sides

The drawsurf for a side will consist of the convex hull of
all points in non-opaque clusters, which allows overlaps
to be trimmed off automatically.
=====================
*/
void ClipSidesIntoTree( entity_t *e, tree_t *tree ) {
	bspbrush_t		*b;
	int				i;
	winding_t		*w;
	side_t			*side, *newSide;
	shaderInfo_t	*si;

	qprintf( "----- ClipSidesIntoTree -----\n");

	for ( b = e->brushes ; b ; b = b->next ) {
		for ( i = 0 ; i < b->numsides ; i++ ) {
			side = &b->sides[i];
			if ( !side->winding) {
				continue;
			}
			w = CopyWinding( side->winding );
			side->visibleHull = NULL;
			ClipSideIntoTree_r( w, side, tree->headnode );

			w = side->visibleHull;
			if ( !w ) {
				continue;
			}
			si = side->shaderInfo;
			if ( !si ) {
				continue;
			}
			// don't create faces for non-visible sides
			if ( si->surfaceFlags & SURF_NODRAW ) {
				continue;
			}

			// always use the original quad winding for auto sprites
			if ( side->shaderInfo->autosprite ) {
				w = side->winding;
			}
			//
			if ( side->bevel ) {
				Error( "monkey tried to create draw surface for brush bevel" );
			}
			// save this winding as a visible surface
			DrawSurfaceForSide( b, side, w );

			// make a back side for it if needed
			if ( !(si->contents & CONTENTS_FOG) ) {
				continue;
			}

			// duplicate the up-facing side
			w = ReverseWinding( w );
		
			newSide = malloc( sizeof( *side ) );
			*newSide = *side;
			newSide->visibleHull = w;
			newSide->planenum ^= 1;

			// save this winding as a visible surface
			DrawSurfaceForSide( b, newSide, w );

		}
	}
}

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

  FILTER REFERENCES DOWN THE TREE

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

/*
====================
FilterDrawSurfIntoTree

Place a reference to the given drawsurf in every leaf it contacts
We assume that the point mesh aproximation to the curve will get a 
reference into all the leafs we need.
====================
*/
int FilterMapDrawSurfIntoTree( vec3_t point, mapDrawSurface_t *ds, node_t *node ) {
	drawSurfRef_t	*dsr;
	float			d;
	plane_t			*plane;
	int				c;

	if ( node->planenum != PLANENUM_LEAF ) {
		plane = &mapplanes[ node->planenum ];
		d = DotProduct( point, plane->normal ) - plane->dist;
		c = 0;
		if ( d >= -ON_EPSILON ) {
			c += FilterMapDrawSurfIntoTree( point, ds, node->children[0] );
		}
		if ( d <= ON_EPSILON ) {
			c += FilterMapDrawSurfIntoTree( point, ds, node->children[1] );
		}
		return c;
	}

	// if opaque leaf, don't add
	if ( node->opaque ) {
		return 0;
	}

	// add the drawsurf if it hasn't been already
	for ( dsr = node->drawSurfReferences ; dsr ; dsr = dsr->nextRef ) {
		if ( dsr->outputNumber == numDrawSurfaces ) {
			return 0;		// already referenced
		}
	}

	dsr = malloc( sizeof( *dsr ) );
	dsr->outputNumber = numDrawSurfaces;
	dsr->nextRef = node->drawSurfReferences;
	node->drawSurfReferences = dsr;
	return 1;
}

/*
====================
FilterDrawSurfIntoTree_r

Place a reference to the given drawsurf in every leaf it is in
====================
*/
int FilterMapDrawSurfIntoTree_r( winding_t *w, mapDrawSurface_t *ds, node_t *node ) {
	drawSurfRef_t	*dsr;
	plane_t			*plane;
	int				total;
	winding_t		*front, *back;

	if ( node->planenum != PLANENUM_LEAF ) {
		plane = &mapplanes[ node->planenum ];
		ClipWindingEpsilon ( w, plane->normal, plane->dist,
				ON_EPSILON, &front, &back );

		total = 0;
		if ( front ) {
			total += FilterMapDrawSurfIntoTree_r( front, ds, node->children[0] );
		}
		if ( back ) {
			total += FilterMapDrawSurfIntoTree_r( back, ds, node->children[1] );
		}

		FreeWinding( w );
		return total;
	}

	// if opaque leaf, don't add
	if ( node->opaque ) {
		return 0;
	}

	// add the drawsurf if it hasn't been already
	for ( dsr = node->drawSurfReferences ; dsr ; dsr = dsr->nextRef ) {
		if ( dsr->outputNumber == numDrawSurfaces ) {
			return 0;		// already referenced
		}
	}

	dsr = malloc( sizeof( *dsr ) );
	dsr->outputNumber = numDrawSurfaces;
	dsr->nextRef = node->drawSurfReferences;
	node->drawSurfReferences = dsr;
	return 1;
}

/*
====================
FilterSideIntoTree_r

Place a reference to the given drawsurf in every leaf it contacts
====================
*/
int FilterSideIntoTree_r( winding_t *w, side_t *side, mapDrawSurface_t *ds, node_t *node ) {
	drawSurfRef_t	*dsr;
	plane_t			*plane;
	winding_t		*front, *back;
	int				total;

	if ( !w ) {
		return 0;
	}

	if ( node->planenum != PLANENUM_LEAF ) {
		if ( side->planenum == node->planenum ) {
			return FilterSideIntoTree_r( w, side, ds, node->children[0] );
		}
		if ( side->planenum == ( node->planenum ^ 1) ) {
			return FilterSideIntoTree_r( w, side, ds, node->children[1] );
		}

		plane = &mapplanes[ node->planenum ];
		ClipWindingEpsilon ( w, plane->normal, plane->dist,
				ON_EPSILON, &front, &back );

		total = FilterSideIntoTree_r( front, side, ds, node->children[0] );
		total += FilterSideIntoTree_r( back, side, ds, node->children[1] );

		FreeWinding( w );
		return total;
	}

	// if opaque leaf, don't add
	if ( node->opaque ) {
		return 0;
	}

	dsr = malloc( sizeof( *dsr ) );
	dsr->outputNumber = numDrawSurfaces;
	dsr->nextRef = node->drawSurfReferences;
	node->drawSurfReferences = dsr;

	FreeWinding( w );
	return 1;
}


/*
=====================
FilterFaceIntoTree
=====================
*/
int	FilterFaceIntoTree( mapDrawSurface_t *ds, tree_t *tree ) {
	int			l;
	winding_t	*w;

	w = WindingFromDrawSurf( ds );
	l = FilterSideIntoTree_r( w, ds->side, ds, tree->headnode );

	return l;
}



/*
=====================
FilterPatchSurfIntoTree
=====================
*/
#define	SUBDIVISION_LIMIT		8.0
int FilterPatchSurfIntoTree( mapDrawSurface_t *ds, tree_t *tree ) {
	int					i, j;
	int					l;
	mesh_t				baseMesh, *subdividedMesh;
	winding_t			*w;

	baseMesh.width = ds->patchWidth;
	baseMesh.height = ds->patchHeight;
	baseMesh.verts = ds->verts;
	subdividedMesh = SubdivideMesh( baseMesh, SUBDIVISION_LIMIT, 32 );

	l = 0;
	for (i = 0; i < subdividedMesh->width-1; i++) {
		for (j = 0; j < subdividedMesh->height-1; j++) {
			w = AllocWinding(3);
			VectorCopy(subdividedMesh->verts[j * subdividedMesh->width + i].xyz, w->p[0]);
			VectorCopy(subdividedMesh->verts[j * subdividedMesh->width + i + 1].xyz, w->p[1]);
			VectorCopy(subdividedMesh->verts[(j+1) * subdividedMesh->width + i].xyz, w->p[2]);
			w->numpoints = 3;
			l += FilterMapDrawSurfIntoTree_r( w, ds, tree->headnode );
			w = AllocWinding(3);
			VectorCopy(subdividedMesh->verts[j * subdividedMesh->width + i + 1].xyz, w->p[0]);
			VectorCopy(subdividedMesh->verts[(j+1) * subdividedMesh->width + i + 1].xyz, w->p[1]);
			VectorCopy(subdividedMesh->verts[(j+1) * subdividedMesh->width + i].xyz, w->p[2]);
			w->numpoints = 3;
			l += FilterMapDrawSurfIntoTree_r( w, ds, tree->headnode );
		}
	}

	// also use the old point filtering into the tree
	for ( i = 0 ; i < subdividedMesh->width * subdividedMesh->height ; i++ ) {
		l += FilterMapDrawSurfIntoTree( subdividedMesh->verts[i].xyz, ds, tree->headnode );
	}

	free(subdividedMesh);

	return l;
}


/*
=====================
FilterMiscModelSurfIntoTree
=====================
*/
int	FilterMiscModelSurfIntoTree( mapDrawSurface_t *ds, tree_t *tree ) {
	int			i;
	int			l;
	winding_t *w;

	l = 0;
	for (i = 0; i < ds->numIndexes-2; i++) {
		w = AllocWinding(3);
		VectorCopy(ds->verts[ds->indexes[i]].xyz, w->p[0]);
		VectorCopy(ds->verts[ds->indexes[i+1]].xyz, w->p[1]);
		VectorCopy(ds->verts[ds->indexes[i+2]].xyz, w->p[2]);
		w->numpoints = 3;
		l += FilterMapDrawSurfIntoTree_r( w, ds, tree->headnode );
	}

	// also use the old point filtering into the tree
	for ( i = 0 ; i < ds->numVerts ; i++ ) {
		l += FilterMapDrawSurfIntoTree( ds->verts[i].xyz, ds, tree->headnode );
	}

	return l;
}

/*
=====================
FilterFlareSurfIntoTree
=====================
*/
int	FilterFlareSurfIntoTree( mapDrawSurface_t *ds, tree_t *tree ) {
	return FilterMapDrawSurfIntoTree( ds->lightmapOrigin, ds, tree->headnode );
}


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

int		c_stripSurfaces, c_fanSurfaces;

/*
==================
IsTriangleDegenerate

Returns qtrue if all three points are collinear or backwards
===================
*/
#define	COLINEAR_AREA	10
static qboolean	IsTriangleDegenerate( drawVert_t *points, int a, int b, int c ) {
	vec3_t		v1, v2, v3;
	float		d;

	VectorSubtract( points[b].xyz, points[a].xyz, v1 );
	VectorSubtract( points[c].xyz, points[a].xyz, v2 );
	CrossProduct( v1, v2, v3 );
	d = VectorLength( v3 );

	// assume all very small or backwards triangles will cause problems
	if ( d < COLINEAR_AREA ) {
		return qtrue;
	}

	return qfalse;
}

/*
===============
SurfaceAsTriFan

The surface can't be represented as a single tristrip without
leaving a degenerate triangle (and therefore a crack), so add
a point in the middle and create (points-1) triangles in fan order
===============
*/
static void SurfaceAsTriFan( dsurface_t *ds ) {
	int					i;
	int					colorSum[4];
	drawVert_t			*mid, *v;

	// create a new point in the center of the face
	if ( numDrawVerts == MAX_MAP_DRAW_VERTS ) {
		Error( "MAX_MAP_DRAW_VERTS" );
	}
	mid = &drawVerts[ numDrawVerts ];
	numDrawVerts++;

	colorSum[0] = colorSum[1] = colorSum[2] = colorSum[3] = 0;

	v = drawVerts + ds->firstVert;
	for (i = 0 ; i < ds->numVerts ; i++, v++ ) {
		VectorAdd( mid->xyz, v->xyz, mid->xyz );
		mid->st[0] += v->st[0];
		mid->st[1] += v->st[1];
		mid->lightmap[0] += v->lightmap[0];
		mid->lightmap[1] += v->lightmap[1];

		colorSum[0] += v->color[0];
		colorSum[1] += v->color[1];
		colorSum[2] += v->color[2];
		colorSum[3] += v->color[3];
	}

	mid->xyz[0] /= ds->numVerts;
	mid->xyz[1] /= ds->numVerts;
	mid->xyz[2] /= ds->numVerts;

	mid->st[0] /= ds->numVerts;
	mid->st[1] /= ds->numVerts;

	mid->lightmap[0] /= ds->numVerts;
	mid->lightmap[1] /= ds->numVerts;

	mid->color[0] = colorSum[0] / ds->numVerts;
	mid->color[1] = colorSum[1] / ds->numVerts;
	mid->color[2] = colorSum[2] / ds->numVerts;
	mid->color[3] = colorSum[3] / ds->numVerts;

	VectorCopy((drawVerts+ds->firstVert)->normal, mid->normal );

	// fill in indices in trifan order
	if ( numDrawIndexes + ds->numVerts*3 > MAX_MAP_DRAW_INDEXES ) {
		Error( "MAX_MAP_DRAWINDEXES" );
	}
	ds->firstIndex = numDrawIndexes;
	ds->numIndexes = ds->numVerts*3;

	//FIXME
	// should be: for ( i = 0 ; i < ds->numVerts ; i++ ) {
	// set a break point and test this in a map
	//for ( i = 0 ; i < ds->numVerts*3 ; i++ ) {
	for ( i = 0 ; i < ds->numVerts ; i++ ) {
		drawIndexes[numDrawIndexes++] = ds->numVerts;
		drawIndexes[numDrawIndexes++] = i;
		drawIndexes[numDrawIndexes++] = (i+1) % ds->numVerts;
	}

	ds->numVerts++;
}


/*
================
SurfaceAsTristrip

Try to create indices that make (points-2) triangles in tristrip order
================
*/
#define	MAX_INDICES	1024
static void SurfaceAsTristrip( dsurface_t *ds ) {
	int					i;
	int					rotate;
	int					numIndices;
	int					ni;
	int					a, b, c;
	int					indices[MAX_INDICES];

	// determine the triangle strip order
	numIndices = ( ds->numVerts - 2 ) * 3;
	if ( numIndices > MAX_INDICES ) {
		Error( "MAX_INDICES exceeded for surface" );
	}

	// try all possible orderings of the points looking
	// for a strip order that isn't degenerate
	for ( rotate = 0 ; rotate < ds->numVerts ; rotate++ ) {
		for ( ni = 0, i = 0 ; i < ds->numVerts - 2 - i ; i++ ) {
			a = ( ds->numVerts - 1 - i + rotate ) % ds->numVerts;
			b = ( i + rotate ) % ds->numVerts;
			c = ( ds->numVerts - 2 - i + rotate ) % ds->numVerts;

			if ( IsTriangleDegenerate( drawVerts + ds->firstVert, a, b, c ) ) {
				break;
			}
			indices[ni++] = a;
			indices[ni++] = b;
			indices[ni++] = c;

			if ( i + 1 != ds->numVerts - 1 - i ) {
				a = ( ds->numVerts - 2 - i + rotate ) % ds->numVerts;
				b = ( i + rotate ) % ds->numVerts;
				c = ( i + 1 + rotate ) % ds->numVerts;

				if ( IsTriangleDegenerate( drawVerts + ds->firstVert, a, b, c ) ) {
					break;
				}
				indices[ni++] = a;
				indices[ni++] = b;
				indices[ni++] = c;
			}
		}
		if ( ni == numIndices ) {
			break;		// got it done without degenerate triangles
		}
	}

	// if any triangle in the strip is degenerate,
	// render from a centered fan point instead
	if ( ni < numIndices ) {
		c_fanSurfaces++;
		SurfaceAsTriFan( ds );
		return;
	}

	// a normal tristrip
	c_stripSurfaces++;

	if ( numDrawIndexes + ni > MAX_MAP_DRAW_INDEXES ) {
		Error( "MAX_MAP_DRAW_INDEXES" );
	}
	ds->firstIndex = numDrawIndexes;
	ds->numIndexes = ni;

	memcpy( drawIndexes + numDrawIndexes, indices, ni * sizeof(int) );
	numDrawIndexes += ni;
}

/*
===============
EmitPlanarSurf
===============
*/
void EmitPlanarSurf( mapDrawSurface_t *ds ) {
	int				j;
	dsurface_t		*out;
	drawVert_t		*outv;

	if ( numDrawSurfaces == MAX_MAP_DRAW_SURFS ) {
		Error( "MAX_MAP_DRAW_SURFS" );
	}
	out = &drawSurfaces[ numDrawSurfaces ];
	numDrawSurfaces++;

	out->surfaceType = MST_PLANAR;
	out->shaderNum = EmitShader( ds->shaderInfo->shader );
	out->firstVert = numDrawVerts;
	out->numVerts = ds->numVerts;
	out->fogNum = ds->fogNum;
	out->lightmapNum = ds->lightmapNum;
	out->lightmapX = ds->lightmapX;
	out->lightmapY = ds->lightmapY;
	out->lightmapWidth = ds->lightmapWidth;
	out->lightmapHeight = ds->lightmapHeight;

	VectorCopy( ds->lightmapOrigin, out->lightmapOrigin );
	VectorCopy( ds->lightmapVecs[0], out->lightmapVecs[0] );
	VectorCopy( ds->lightmapVecs[1], out->lightmapVecs[1] );
	VectorCopy( ds->lightmapVecs[2], out->lightmapVecs[2] );

	for ( j = 0 ; j < ds->numVerts ; j++ ) {
		if ( numDrawVerts == MAX_MAP_DRAW_VERTS ) {
			Error( "MAX_MAP_DRAW_VERTS" );
		}
		outv = &drawVerts[ numDrawVerts ];
		numDrawVerts++;
		memcpy( outv, &ds->verts[ j ], sizeof( *outv ) );
		outv->color[0] = 255;
		outv->color[1] = 255;
		outv->color[2] = 255;
		outv->color[3] = 255;
	}

	// create the indexes
	SurfaceAsTristrip( out );
}


/*
===============
EmitPatchSurf
===============
*/
void EmitPatchSurf( mapDrawSurface_t *ds ) {
	int				j;
	dsurface_t		*out;
	drawVert_t		*outv;

	if ( numDrawSurfaces == MAX_MAP_DRAW_SURFS ) {
		Error( "MAX_MAP_DRAW_SURFS" );
	}
	out = &drawSurfaces[ numDrawSurfaces ];
	numDrawSurfaces++;

	out->surfaceType = MST_PATCH;
	out->shaderNum = EmitShader( ds->shaderInfo->shader );
	out->firstVert = numDrawVerts;
	out->numVerts = ds->numVerts;
	out->firstIndex = numDrawIndexes;
	out->numIndexes = ds->numIndexes;
	out->patchWidth = ds->patchWidth;
	out->patchHeight = ds->patchHeight;
	out->fogNum = ds->fogNum;
	out->lightmapNum = ds->lightmapNum;
	out->lightmapX = ds->lightmapX;
	out->lightmapY = ds->lightmapY;
	out->lightmapWidth = ds->lightmapWidth;
	out->lightmapHeight = ds->lightmapHeight;

	VectorCopy( ds->lightmapOrigin, out->lightmapOrigin );
	VectorCopy( ds->lightmapVecs[0], out->lightmapVecs[0] );
	VectorCopy( ds->lightmapVecs[1], out->lightmapVecs[1] );
	VectorCopy( ds->lightmapVecs[2], out->lightmapVecs[2] );

	for ( j = 0 ; j < ds->numVerts ; j++ ) {
		if ( numDrawVerts == MAX_MAP_DRAW_VERTS ) {
			Error( "MAX_MAP_DRAW_VERTS" );
		}
		outv = &drawVerts[ numDrawVerts ];
		numDrawVerts++;
		memcpy( outv, &ds->verts[ j ], sizeof( *outv ) );
		outv->color[0] = 255;
		outv->color[1] = 255;
		outv->color[2] = 255;
		outv->color[3] = 255;
	}

	for ( j = 0 ; j < ds->numIndexes ; j++ ) {
		if ( numDrawIndexes == MAX_MAP_DRAW_INDEXES ) {
			Error( "MAX_MAP_DRAW_INDEXES" );
		}
		drawIndexes[ numDrawIndexes ] = ds->indexes[ j ];
		numDrawIndexes++;
	}
}

/*
===============
EmitFlareSurf
===============
*/
void EmitFlareSurf( mapDrawSurface_t *ds ) {
	dsurface_t		*out;

	if ( numDrawSurfaces == MAX_MAP_DRAW_SURFS ) {
		Error( "MAX_MAP_DRAW_SURFS" );
	}
	out = &drawSurfaces[ numDrawSurfaces ];
	numDrawSurfaces++;

	out->surfaceType = MST_FLARE;
	out->shaderNum = EmitShader( ds->shaderInfo->shader );
	out->fogNum = ds->fogNum;

	VectorCopy( ds->lightmapOrigin, out->lightmapOrigin );
	VectorCopy( ds->lightmapVecs[0], out->lightmapVecs[0] );	// color
	VectorCopy( ds->lightmapVecs[2], out->lightmapVecs[2] );
}


/*
===============
EmitModelSurf
===============
*/
void EmitModelSurf( mapDrawSurface_t *ds ) {
	int				j;
	dsurface_t		*out;
	drawVert_t		*outv;

	if ( numDrawSurfaces == MAX_MAP_DRAW_SURFS ) {
		Error( "MAX_MAP_DRAW_SURFS" );
	}
	out = &drawSurfaces[ numDrawSurfaces ];
	numDrawSurfaces++;

	out->surfaceType = MST_TRIANGLE_SOUP;
	out->shaderNum = EmitShader( ds->shaderInfo->shader );
	out->firstVert = numDrawVerts;
	out->numVerts = ds->numVerts;
	out->firstIndex = numDrawIndexes;
	out->numIndexes = ds->numIndexes;
	out->patchWidth = ds->patchWidth;
	out->patchHeight = ds->patchHeight;
	out->fogNum = ds->fogNum;
	out->lightmapNum = ds->lightmapNum;
	out->lightmapX = ds->lightmapX;
	out->lightmapY = ds->lightmapY;
	out->lightmapWidth = ds->lightmapWidth;
	out->lightmapHeight = ds->lightmapHeight;

	VectorCopy( ds->lightmapOrigin, out->lightmapOrigin );
	VectorCopy( ds->lightmapVecs[0], out->lightmapVecs[0] );
	VectorCopy( ds->lightmapVecs[1], out->lightmapVecs[1] );
	VectorCopy( ds->lightmapVecs[2], out->lightmapVecs[2] );

	for ( j = 0 ; j < ds->numVerts ; j++ ) {
		if ( numDrawVerts == MAX_MAP_DRAW_VERTS ) {
			Error( "MAX_MAP_DRAW_VERTS" );
		}
		outv = &drawVerts[ numDrawVerts ];
		numDrawVerts++;
		memcpy( outv, &ds->verts[ j ], sizeof( *outv ) );
		outv->color[0] = 255;
		outv->color[1] = 255;
		outv->color[2] = 255;
	}

	for ( j = 0 ; j < ds->numIndexes ; j++ ) {
		if ( numDrawIndexes == MAX_MAP_DRAW_INDEXES ) {
			Error( "MAX_MAP_DRAW_INDEXES" );
		}
		drawIndexes[ numDrawIndexes ] = ds->indexes[ j ];
		numDrawIndexes++;
	}
}

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

/*
==================
CreateFlareSurface

Light flares from surface lights become 
==================
*/
void CreateFlareSurface( mapDrawSurface_t *faceDs ) {
	mapDrawSurface_t	*ds;
	int					i;

	ds = AllocDrawSurf();

	if ( faceDs->shaderInfo->flareShader[0] ) {
		ds->shaderInfo = ShaderInfoForShader( faceDs->shaderInfo->flareShader );
	} else {
		ds->shaderInfo = ShaderInfoForShader( "flareshader" );
	}
	ds->flareSurface = qtrue;
	VectorCopy( faceDs->lightmapVecs[2], ds->lightmapVecs[2] );

	// find midpoint
	VectorClear( ds->lightmapOrigin );
	for ( i = 0 ; i < faceDs->numVerts ; i++ ) {
		VectorAdd( ds->lightmapOrigin, faceDs->verts[i].xyz, ds->lightmapOrigin );
	}
	VectorScale( ds->lightmapOrigin, 1.0/faceDs->numVerts, ds->lightmapOrigin );

	VectorMA( ds->lightmapOrigin, 2,  ds->lightmapVecs[2], ds->lightmapOrigin );

	VectorCopy( faceDs->shaderInfo->color, ds->lightmapVecs[0] );

	// FIXME: fog
}

/*
=====================
FilterDrawsurfsIntoTree

Upon completion, all drawsurfs that actually generate a reference
will have been emited to the bspfile arrays, and the references
will have valid final indexes
=====================
*/
void FilterDrawsurfsIntoTree( entity_t *e, tree_t *tree ) {
	int				i;
	mapDrawSurface_t	*ds;
	int				refs;
	int				c_surfs, c_refs;

	qprintf( "----- FilterDrawsurfsIntoTree -----\n");

	c_surfs = 0;
	c_refs = 0;
	for ( i = e->firstDrawSurf ; i < numMapDrawSurfs ; i++ ) {
		ds = &mapDrawSurfs[i];

		if ( !ds->numVerts && !ds->flareSurface ) {
			continue;
		}
		if ( ds->miscModel ) {
			refs = FilterMiscModelSurfIntoTree( ds, tree );
			EmitModelSurf( ds );		
		} else if ( ds->patch ) {
			refs = FilterPatchSurfIntoTree( ds, tree );
			EmitPatchSurf( ds );		
		} else if ( ds->flareSurface ) {
			refs = FilterFlareSurfIntoTree( ds, tree );
			EmitFlareSurf( ds );					
		} else {
			refs = FilterFaceIntoTree( ds, tree );
//			if ( ds->shaderInfo->value >= 1000 ) { // ds->shaderInfo->flareShader[0] ) {
			if ( ds->shaderInfo->flareShader[0] ) {
				CreateFlareSurface( ds );
			}
			EmitPlanarSurf( ds );		
		}
		if ( refs > 0 ) {
			c_surfs++;
			c_refs += refs;
		}
	}
	qprintf( "%5i emited drawsurfs\n", c_surfs );
	qprintf( "%5i references\n", c_refs );
	qprintf( "%5i stripfaces\n", c_stripSurfaces );
	qprintf( "%5i fanfaces\n", c_fanSurfaces );
}