/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.
Copyright (C) 2006 Robert Beckebans <trebor_7@users.sourceforge.net>

This file is part of XreaL source code.

XreaL 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.

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

#include "cm_local.h"
#include "cm_patch.h"

/*

This file does not reference any globals, and has these entry points:

void CM_ClearLevelPatches( void );
struct patchCollide_s	*CM_GeneratePatchCollide( int width, int height, const vec3_t *points );
void CM_TraceThroughPatchCollide( traceWork_t *tw, const struct patchCollide_s *pc );
qboolean CM_PositionTestInPatchCollide( traceWork_t *tw, const struct patchCollide_s *pc );
void CM_DrawDebugSurface( void (*drawPoly)(int color, int numPoints, flaot *points) );


WARNING: this may misbehave with meshes that have rows or columns that only
degenerate a few triangles.  Completely degenerate rows and columns are handled
properly.
*/

/*
#define	MAX_FACETS			1024
#define	MAX_PATCH_PLANES	2048

typedef struct {
	float	plane[4];
	int		signbits;		// signx + (signy<<1) + (signz<<2), used as lookup during collision
} patchPlane_t;

typedef struct {
	int			surfacePlane;
	int			numBorders;		// 3 or four + 6 axial bevels + 4 or 3 * 4 edge bevels
	int			borderPlanes[4+6+16];
	int			borderInward[4+6+16];
	qboolean	borderNoAdjust[4+6+16];
} facet_t;

typedef struct patchCollide_s {
	vec3_t	bounds[2];
	int		numPlanes;			// surface planes plus edge planes
	patchPlane_t	*planes;
	int		numFacets;
	facet_t	*facets;
} patchCollide_t;


#define	MAX_GRID_SIZE	129

typedef struct {
	int			width;
	int			height;
	qboolean	wrapWidth;
	qboolean	wrapHeight;
	vec3_t	points[MAX_GRID_SIZE][MAX_GRID_SIZE];	// [width][height]
} cGrid_t;

#define	SUBDIVIDE_DISTANCE	16	//4	// never more than this units away from curve
#define	PLANE_TRI_EPSILON	0.1
#define	WRAP_POINT_EPSILON	0.1
*/

int             c_totalPatchBlocks;
int             c_totalPatchSurfaces;
int             c_totalPatchEdges;

static const patchCollide_t *debugPatchCollide;
static const facet_t *debugFacet;
static qboolean debugBlock;
static vec3_t   debugBlockPoints[4];

/*
=================
CM_ClearLevelPatches
=================
*/
void CM_ClearLevelPatches(void)
{
	debugPatchCollide = NULL;
	debugFacet = NULL;
}

/*
=================
CM_SignbitsForNormal
=================
*/
static int CM_SignbitsForNormal(vec3_t normal)
{
	int             bits, j;

	bits = 0;
	for(j = 0; j < 3; j++)
	{
		if(normal[j] < 0)
		{
			bits |= 1 << j;
		}
	}
	return bits;
}

/*
=====================
CM_PlaneFromPoints

Returns false if the triangle is degenrate.
The normal will point out of the clock for clockwise ordered points
=====================
*/
static qboolean CM_PlaneFromPoints(vec4_t plane, vec3_t a, vec3_t b, vec3_t c)
{
	vec3_t          d1, d2;

	VectorSubtract(b, a, d1);
	VectorSubtract(c, a, d2);
	CrossProduct(d2, d1, plane);
	if(VectorNormalize(plane) == 0)
	{
		return qfalse;
	}

	plane[3] = DotProduct(a, plane);
	return qtrue;
}


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

GRID SUBDIVISION

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

/*
=================
CM_NeedsSubdivision

Returns true if the given quadratic curve is not flat enough for our
collision detection purposes
=================
*/
static qboolean CM_NeedsSubdivision(vec3_t a, vec3_t b, vec3_t c)
{
	vec3_t          cmid;
	vec3_t          lmid;
	vec3_t          delta;
	float           dist;
	int             i;

	// calculate the linear midpoint
	for(i = 0; i < 3; i++)
	{
		lmid[i] = 0.5 * (a[i] + c[i]);
	}

	// calculate the exact curve midpoint
	for(i = 0; i < 3; i++)
	{
		cmid[i] = 0.5 * (0.5 * (a[i] + b[i]) + 0.5 * (b[i] + c[i]));
	}

	// see if the curve is far enough away from the linear mid
	VectorSubtract(cmid, lmid, delta);
	dist = VectorLength(delta);

	return dist >= SUBDIVIDE_DISTANCE;
}

/*
===============
CM_Subdivide

a, b, and c are control points.
the subdivided sequence will be: a, out1, out2, out3, c
===============
*/
static void CM_Subdivide(vec3_t a, vec3_t b, vec3_t c, vec3_t out1, vec3_t out2, vec3_t out3)
{
	int             i;

	for(i = 0; i < 3; i++)
	{
		out1[i] = 0.5 * (a[i] + b[i]);
		out3[i] = 0.5 * (b[i] + c[i]);
		out2[i] = 0.5 * (out1[i] + out3[i]);
	}
}

/*
=================
CM_TransposeGrid

Swaps the rows and columns in place
=================
*/
static void CM_TransposeGrid(cGrid_t * grid)
{
	int             i, j, l;
	vec3_t          temp;
	qboolean        tempWrap;

	if(grid->width > grid->height)
	{
		for(i = 0; i < grid->height; i++)
		{
			for(j = i + 1; j < grid->width; j++)
			{
				if(j < grid->height)
				{
					// swap the value
					VectorCopy(grid->points[i][j], temp);
					VectorCopy(grid->points[j][i], grid->points[i][j]);
					VectorCopy(temp, grid->points[j][i]);
				}
				else
				{
					// just copy
					VectorCopy(grid->points[j][i], grid->points[i][j]);
				}
			}
		}
	}
	else
	{
		for(i = 0; i < grid->width; i++)
		{
			for(j = i + 1; j < grid->height; j++)
			{
				if(j < grid->width)
				{
					// swap the value
					VectorCopy(grid->points[j][i], temp);
					VectorCopy(grid->points[i][j], grid->points[j][i]);
					VectorCopy(temp, grid->points[i][j]);
				}
				else
				{
					// just copy
					VectorCopy(grid->points[i][j], grid->points[j][i]);
				}
			}
		}
	}

	l = grid->width;
	grid->width = grid->height;
	grid->height = l;

	tempWrap = grid->wrapWidth;
	grid->wrapWidth = grid->wrapHeight;
	grid->wrapHeight = tempWrap;
}

/*
===================
CM_SetGridWrapWidth

If the left and right columns are exactly equal, set grid->wrapWidth qtrue
===================
*/
static void CM_SetGridWrapWidth(cGrid_t * grid)
{
	int             i, j;
	float           d;

	for(i = 0; i < grid->height; i++)
	{
		for(j = 0; j < 3; j++)
		{
			d = grid->points[0][i][j] - grid->points[grid->width - 1][i][j];
			if(d < -WRAP_POINT_EPSILON || d > WRAP_POINT_EPSILON)
			{
				break;
			}
		}
		if(j != 3)
		{
			break;
		}
	}
	if(i == grid->height)
	{
		grid->wrapWidth = qtrue;
	}
	else
	{
		grid->wrapWidth = qfalse;
	}
}

/*
=================
CM_SubdivideGridColumns

Adds columns as necessary to the grid until
all the aproximating points are within SUBDIVIDE_DISTANCE
from the true curve
=================
*/
static void CM_SubdivideGridColumns(cGrid_t * grid)
{
	int             i, j, k;

	for(i = 0; i < grid->width - 2;)
	{
		// grid->points[i][x] is an interpolating control point
		// grid->points[i+1][x] is an aproximating control point
		// grid->points[i+2][x] is an interpolating control point

		//
		// first see if we can collapse the aproximating collumn away
		//
		for(j = 0; j < grid->height; j++)
		{
			if(CM_NeedsSubdivision(grid->points[i][j], grid->points[i + 1][j], grid->points[i + 2][j]))
			{
				break;
			}
		}
		if(j == grid->height)
		{
			// all of the points were close enough to the linear midpoints
			// that we can collapse the entire column away
			for(j = 0; j < grid->height; j++)
			{
				// remove the column
				for(k = i + 2; k < grid->width; k++)
				{
					VectorCopy(grid->points[k][j], grid->points[k - 1][j]);
				}
			}

			grid->width--;

			// go to the next curve segment
			i++;
			continue;
		}

		//
		// we need to subdivide the curve
		//
		for(j = 0; j < grid->height; j++)
		{
			vec3_t          prev, mid, next;

			// save the control points now
			VectorCopy(grid->points[i][j], prev);
			VectorCopy(grid->points[i + 1][j], mid);
			VectorCopy(grid->points[i + 2][j], next);

			// make room for two additional columns in the grid
			// columns i+1 will be replaced, column i+2 will become i+4
			// i+1, i+2, and i+3 will be generated
			for(k = grid->width - 1; k > i + 1; k--)
			{
				VectorCopy(grid->points[k][j], grid->points[k + 2][j]);
			}

			// generate the subdivided points
			CM_Subdivide(prev, mid, next, grid->points[i + 1][j], grid->points[i + 2][j], grid->points[i + 3][j]);
		}

		grid->width += 2;

		// the new aproximating point at i+1 may need to be removed
		// or subdivided farther, so don't advance i
	}
}

/*
======================
CM_ComparePoints
======================
*/
#define	POINT_EPSILON	0.1
static qboolean CM_ComparePoints(float *a, float *b)
{
	float           d;

	d = a[0] - b[0];
	if(d < -POINT_EPSILON || d > POINT_EPSILON)
	{
		return qfalse;
	}
	d = a[1] - b[1];
	if(d < -POINT_EPSILON || d > POINT_EPSILON)
	{
		return qfalse;
	}
	d = a[2] - b[2];
	if(d < -POINT_EPSILON || d > POINT_EPSILON)
	{
		return qfalse;
	}
	return qtrue;
}

/*
=================
CM_RemoveDegenerateColumns

If there are any identical columns, remove them
=================
*/
static void CM_RemoveDegenerateColumns(cGrid_t * grid)
{
	int             i, j, k;

	for(i = 0; i < grid->width - 1; i++)
	{
		for(j = 0; j < grid->height; j++)
		{
			if(!CM_ComparePoints(grid->points[i][j], grid->points[i + 1][j]))
			{
				break;
			}
		}

		if(j != grid->height)
		{
			continue;			// not degenerate
		}

		for(j = 0; j < grid->height; j++)
		{
			// remove the column
			for(k = i + 2; k < grid->width; k++)
			{
				VectorCopy(grid->points[k][j], grid->points[k - 1][j]);
			}
		}
		grid->width--;

		// check against the next column
		i--;
	}
}

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

PATCH COLLIDE GENERATION

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

static int      numPlanes;
static patchPlane_t planes[MAX_PATCH_PLANES];

static int      numFacets;
static facet_t  facets[MAX_PATCH_PLANES];	//maybe MAX_FACETS ??

#define	NORMAL_EPSILON	0.0001
#define	DIST_EPSILON	0.02

/*
==================
CM_PlaneEqual
==================
*/
int CM_PlaneEqual(patchPlane_t * p, float plane[4], int *flipped)
{
	float           invplane[4];

	if(fabs(p->plane[0] - plane[0]) < NORMAL_EPSILON
	   && fabs(p->plane[1] - plane[1]) < NORMAL_EPSILON
	   && fabs(p->plane[2] - plane[2]) < NORMAL_EPSILON && fabs(p->plane[3] - plane[3]) < DIST_EPSILON)
	{
		*flipped = qfalse;
		return qtrue;
	}

	VectorNegate(plane, invplane);
	invplane[3] = -plane[3];

	if(fabs(p->plane[0] - invplane[0]) < NORMAL_EPSILON
	   && fabs(p->plane[1] - invplane[1]) < NORMAL_EPSILON
	   && fabs(p->plane[2] - invplane[2]) < NORMAL_EPSILON && fabs(p->plane[3] - invplane[3]) < DIST_EPSILON)
	{
		*flipped = qtrue;
		return qtrue;
	}

	return qfalse;
}

/*
==================
CM_SnapVector
==================
*/
void CM_SnapVector(vec3_t normal)
{
	int             i;

	for(i = 0; i < 3; i++)
	{
		if(fabs(normal[i] - 1) < NORMAL_EPSILON)
		{
			VectorClear(normal);
			normal[i] = 1;
			break;
		}
		if(fabs(normal[i] - -1) < NORMAL_EPSILON)
		{
			VectorClear(normal);
			normal[i] = -1;
			break;
		}
	}
}

/*
==================
CM_FindPlane2
==================
*/
int CM_FindPlane2(float plane[4], int *flipped)
{
	int             i;

	// see if the points are close enough to an existing plane
	for(i = 0; i < numPlanes; i++)
	{
		if(CM_PlaneEqual(&planes[i], plane, flipped))
			return i;
	}

	// add a new plane
	if(numPlanes == MAX_PATCH_PLANES)
	{
		Com_Error(ERR_DROP, "MAX_PATCH_PLANES");
	}

	VectorCopy4(plane, planes[numPlanes].plane);
	planes[numPlanes].signbits = CM_SignbitsForNormal(plane);

	numPlanes++;

	*flipped = qfalse;

	return numPlanes - 1;
}

/*
==================
CM_FindPlane
==================
*/
static int CM_FindPlane(float *p1, float *p2, float *p3)
{
	float           plane[4];
	int             i;
	float           d;

	if(!CM_PlaneFromPoints(plane, p1, p2, p3))
	{
		return -1;
	}

	// see if the points are close enough to an existing plane
	for(i = 0; i < numPlanes; i++)
	{
		if(DotProduct(plane, planes[i].plane) < 0)
		{
			continue;			// allow backwards planes?
		}

		d = DotProduct(p1, planes[i].plane) - planes[i].plane[3];
		if(d < -PLANE_TRI_EPSILON || d > PLANE_TRI_EPSILON)
		{
			continue;
		}

		d = DotProduct(p2, planes[i].plane) - planes[i].plane[3];
		if(d < -PLANE_TRI_EPSILON || d > PLANE_TRI_EPSILON)
		{
			continue;
		}

		d = DotProduct(p3, planes[i].plane) - planes[i].plane[3];
		if(d < -PLANE_TRI_EPSILON || d > PLANE_TRI_EPSILON)
		{
			continue;
		}

		// found it
		return i;
	}

	// add a new plane
	if(numPlanes == MAX_PATCH_PLANES)
	{
		Com_Error(ERR_DROP, "MAX_PATCH_PLANES");
	}

	VectorCopy4(plane, planes[numPlanes].plane);
	planes[numPlanes].signbits = CM_SignbitsForNormal(plane);

	numPlanes++;

	return numPlanes - 1;
}

/*
==================
CM_PointOnPlaneSide
==================
*/
static int CM_PointOnPlaneSide(float *p, int planeNum)
{
	float          *plane;
	float           d;

	if(planeNum == -1)
	{
		return SIDE_ON;
	}
	plane = planes[planeNum].plane;

	d = DotProduct(p, plane) - plane[3];

	if(d > PLANE_TRI_EPSILON)
	{
		return SIDE_FRONT;
	}

	if(d < -PLANE_TRI_EPSILON)
	{
		return SIDE_BACK;
	}

	return SIDE_ON;
}

/*
==================
CM_GridPlane
==================
*/
static int CM_GridPlane(int gridPlanes[MAX_GRID_SIZE][MAX_GRID_SIZE][2], int i, int j, int tri)
{
	int             p;

	p = gridPlanes[i][j][tri];
	if(p != -1)
	{
		return p;
	}
	p = gridPlanes[i][j][!tri];
	if(p != -1)
	{
		return p;
	}

	// should never happen
	Com_Printf("WARNING: CM_GridPlane unresolvable\n");
	return -1;
}

/*
==================
CM_EdgePlaneNum
==================
*/
static int CM_EdgePlaneNum(cGrid_t * grid, int gridPlanes[MAX_GRID_SIZE][MAX_GRID_SIZE][2], int i, int j, int k)
{
	float          *p1, *p2;
	vec3_t          up;
	int             p;

	switch (k)
	{
		case 0:				// top border
			p1 = grid->points[i][j];
			p2 = grid->points[i + 1][j];
			p = CM_GridPlane(gridPlanes, i, j, 0);
			VectorMA(p1, 4, planes[p].plane, up);
			return CM_FindPlane(p1, p2, up);

		case 2:				// bottom border
			p1 = grid->points[i][j + 1];
			p2 = grid->points[i + 1][j + 1];
			p = CM_GridPlane(gridPlanes, i, j, 1);
			VectorMA(p1, 4, planes[p].plane, up);
			return CM_FindPlane(p2, p1, up);

		case 3:				// left border
			p1 = grid->points[i][j];
			p2 = grid->points[i][j + 1];
			p = CM_GridPlane(gridPlanes, i, j, 1);
			VectorMA(p1, 4, planes[p].plane, up);
			return CM_FindPlane(p2, p1, up);

		case 1:				// right border
			p1 = grid->points[i + 1][j];
			p2 = grid->points[i + 1][j + 1];
			p = CM_GridPlane(gridPlanes, i, j, 0);
			VectorMA(p1, 4, planes[p].plane, up);
			return CM_FindPlane(p1, p2, up);

		case 4:				// diagonal out of triangle 0
			p1 = grid->points[i + 1][j + 1];
			p2 = grid->points[i][j];
			p = CM_GridPlane(gridPlanes, i, j, 0);
			VectorMA(p1, 4, planes[p].plane, up);
			return CM_FindPlane(p1, p2, up);

		case 5:				// diagonal out of triangle 1
			p1 = grid->points[i][j];
			p2 = grid->points[i + 1][j + 1];
			p = CM_GridPlane(gridPlanes, i, j, 1);
			VectorMA(p1, 4, planes[p].plane, up);
			return CM_FindPlane(p1, p2, up);

	}

	Com_Error(ERR_DROP, "CM_EdgePlaneNum: bad k");
	return -1;
}

/*
===================
CM_SetBorderInward
===================
*/
static void CM_SetBorderInward(facet_t * facet, cGrid_t * grid, int gridPlanes[MAX_GRID_SIZE][MAX_GRID_SIZE][2],
							   int i, int j, int which)
{
	int             k, l;
	float          *points[4];
	int             numPoints;

	switch (which)
	{
		case -1:
			points[0] = grid->points[i][j];
			points[1] = grid->points[i + 1][j];
			points[2] = grid->points[i + 1][j + 1];
			points[3] = grid->points[i][j + 1];
			numPoints = 4;
			break;
		case 0:
			points[0] = grid->points[i][j];
			points[1] = grid->points[i + 1][j];
			points[2] = grid->points[i + 1][j + 1];
			numPoints = 3;
			break;
		case 1:
			points[0] = grid->points[i + 1][j + 1];
			points[1] = grid->points[i][j + 1];
			points[2] = grid->points[i][j];
			numPoints = 3;
			break;
		default:
			Com_Error(ERR_FATAL, "CM_SetBorderInward: bad parameter");
			numPoints = 0;
			break;
	}

	for(k = 0; k < facet->numBorders; k++)
	{
		int             front, back;

		front = 0;
		back = 0;

		for(l = 0; l < numPoints; l++)
		{
			int             side;

			side = CM_PointOnPlaneSide(points[l], facet->borderPlanes[k]);
			if(side == SIDE_FRONT)
			{
				front++;
			}
			if(side == SIDE_BACK)
			{
				back++;
			}
		}

		if(front && !back)
		{
			facet->borderInward[k] = qtrue;
		}
		else if(back && !front)
		{
			facet->borderInward[k] = qfalse;
		}
		else if(!front && !back)
		{
			// flat side border
			facet->borderPlanes[k] = -1;
		}
		else
		{
			// bisecting side border
			Com_DPrintf("WARNING: CM_SetBorderInward: mixed plane sides\n");
			facet->borderInward[k] = qfalse;
			if(!debugBlock)
			{
				debugBlock = qtrue;
				VectorCopy(grid->points[i][j], debugBlockPoints[0]);
				VectorCopy(grid->points[i + 1][j], debugBlockPoints[1]);
				VectorCopy(grid->points[i + 1][j + 1], debugBlockPoints[2]);
				VectorCopy(grid->points[i][j + 1], debugBlockPoints[3]);
			}
		}
	}
}

/*
==================
CM_ValidateFacet

If the facet isn't bounded by its borders, we screwed up.
==================
*/
static qboolean CM_ValidateFacet(facet_t * facet)
{
	float           plane[4];
	int             j;
	winding_t      *w;
	vec3_t          bounds[2];

	if(facet->surfacePlane == -1)
	{
		return qfalse;
	}

	VectorCopy4(planes[facet->surfacePlane].plane, plane);
	w = BaseWindingForPlane(plane, plane[3]);
	for(j = 0; j < facet->numBorders && w; j++)
	{
		if(facet->borderPlanes[j] == -1)
		{
			FreeWinding(w);
			return qfalse;
		}
		VectorCopy4(planes[facet->borderPlanes[j]].plane, plane);
		if(!facet->borderInward[j])
		{
			VectorSubtract(vec3_origin, plane, plane);
			plane[3] = -plane[3];
		}
		ChopWindingInPlace(&w, plane, plane[3], 0.1f);
	}

	if(!w)
	{
		return qfalse;			// winding was completely chopped away
	}

	// see if the facet is unreasonably large
	WindingBounds(w, bounds[0], bounds[1]);
	FreeWinding(w);

	for(j = 0; j < 3; j++)
	{
		if(bounds[1][j] - bounds[0][j] > MAX_MAP_BOUNDS)
		{
			return qfalse;		// we must be missing a plane
		}
		if(bounds[0][j] >= MAX_MAP_BOUNDS)
		{
			return qfalse;
		}
		if(bounds[1][j] <= -MAX_MAP_BOUNDS)
		{
			return qfalse;
		}
	}
	return qtrue;				// winding is fine
}

/*
==================
CM_AddFacetBevels
==================
*/
void CM_AddFacetBevels(facet_t * facet)
{

	int             i, j, k, l;
	int             axis, dir, order, flipped;
	float           plane[4], d, newplane[4];
	winding_t      *w, *w2;
	vec3_t          mins, maxs, vec, vec2;

	VectorCopy4(planes[facet->surfacePlane].plane, plane);

	w = BaseWindingForPlane(plane, plane[3]);
	for(j = 0; j < facet->numBorders && w; j++)
	{
		if(facet->borderPlanes[j] == facet->surfacePlane)
			continue;
		VectorCopy4(planes[facet->borderPlanes[j]].plane, plane);

		if(!facet->borderInward[j])
		{
			VectorSubtract(vec3_origin, plane, plane);
			plane[3] = -plane[3];
		}

		ChopWindingInPlace(&w, plane, plane[3], 0.1f);
	}
	if(!w)
	{
		return;
	}

	WindingBounds(w, mins, maxs);

	// add the axial planes
	order = 0;
	for(axis = 0; axis < 3; axis++)
	{
		for(dir = -1; dir <= 1; dir += 2, order++)
		{
			VectorClear(plane);
			plane[axis] = dir;
			if(dir == 1)
			{
				plane[3] = maxs[axis];
			}
			else
			{
				plane[3] = -mins[axis];
			}
			//if it's the surface plane
			if(CM_PlaneEqual(&planes[facet->surfacePlane], plane, &flipped))
			{
				continue;
			}
			// see if the plane is allready present
			for(i = 0; i < facet->numBorders; i++)
			{
				if(CM_PlaneEqual(&planes[facet->borderPlanes[i]], plane, &flipped))
					break;
			}

			if(i == facet->numBorders)
			{
				if(facet->numBorders > 4 + 6 + 16)
					Com_Printf("ERROR: too many bevels\n");
				facet->borderPlanes[facet->numBorders] = CM_FindPlane2(plane, &flipped);
				facet->borderNoAdjust[facet->numBorders] = 0;
				facet->borderInward[facet->numBorders] = flipped;
				facet->numBorders++;
			}
		}
	}
	//
	// add the edge bevels
	//
	// test the non-axial plane edges
	for(j = 0; j < w->numpoints; j++)
	{
		k = (j + 1) % w->numpoints;
		VectorSubtract(w->p[j], w->p[k], vec);
		//if it's a degenerate edge
		if(VectorNormalize(vec) < 0.5)
			continue;
		CM_SnapVector(vec);
		for(k = 0; k < 3; k++)
			if(vec[k] == -1 || vec[k] == 1)
				break;			// axial
		if(k < 3)
			continue;			// only test non-axial edges

		// try the six possible slanted axials from this edge
		for(axis = 0; axis < 3; axis++)
		{
			for(dir = -1; dir <= 1; dir += 2)
			{
				// construct a plane
				VectorClear(vec2);
				vec2[axis] = dir;
				CrossProduct(vec, vec2, plane);
				if(VectorNormalize(plane) < 0.5)
					continue;
				plane[3] = DotProduct(w->p[j], plane);

				// if all the points of the facet winding are
				// behind this plane, it is a proper edge bevel
				for(l = 0; l < w->numpoints; l++)
				{
					d = DotProduct(w->p[l], plane) - plane[3];
					if(d > 0.1)
						break;	// point in front
				}
				if(l < w->numpoints)
					continue;

				//if it's the surface plane
				if(CM_PlaneEqual(&planes[facet->surfacePlane], plane, &flipped))
				{
					continue;
				}
				// see if the plane is allready present
				for(i = 0; i < facet->numBorders; i++)
				{
					if(CM_PlaneEqual(&planes[facet->borderPlanes[i]], plane, &flipped))
					{
						break;
					}
				}

				if(i == facet->numBorders)
				{
					if(facet->numBorders > 4 + 6 + 16)
						Com_Printf("ERROR: too many bevels\n");
					facet->borderPlanes[facet->numBorders] = CM_FindPlane2(plane, &flipped);

					for(k = 0; k < facet->numBorders; k++)
					{
						if(facet->borderPlanes[facet->numBorders] == facet->borderPlanes[k])
							Com_Printf("WARNING: bevel plane already used\n");
					}

					facet->borderNoAdjust[facet->numBorders] = 0;
					facet->borderInward[facet->numBorders] = flipped;
					//
					w2 = CopyWinding(w);
					VectorCopy4(planes[facet->borderPlanes[facet->numBorders]].plane, newplane);
					if(!facet->borderInward[facet->numBorders])
					{
						VectorNegate(newplane, newplane);
						newplane[3] = -newplane[3];
					}			//end if
					ChopWindingInPlace(&w2, newplane, newplane[3], 0.1f);
					if(!w2)
					{
						Com_DPrintf("WARNING: CM_AddFacetBevels... invalid bevel\n");
						continue;
					}
					else
					{
						FreeWinding(w2);
					}
					//
					facet->numBorders++;
					//already got a bevel
//                  break;
				}
			}
		}
	}
	FreeWinding(w);

#ifndef BSPC
	//add opposite plane
	facet->borderPlanes[facet->numBorders] = facet->surfacePlane;
	facet->borderNoAdjust[facet->numBorders] = 0;
	facet->borderInward[facet->numBorders] = qtrue;
	facet->numBorders++;
#endif							//BSPC

}

typedef enum
{
	EN_TOP,
	EN_RIGHT,
	EN_BOTTOM,
	EN_LEFT
} edgeName_t;

/*
==================
CM_PatchCollideFromGrid
==================
*/
static void CM_PatchCollideFromGrid(cGrid_t * grid, patchCollide_t * pf)
{
	int             i, j;
	float          *p1, *p2, *p3;
	int             gridPlanes[MAX_GRID_SIZE][MAX_GRID_SIZE][2];
	facet_t        *facet;
	int             borders[4];
	int             noAdjust[4];

	numPlanes = 0;
	numFacets = 0;

	// find the planes for each triangle of the grid
	for(i = 0; i < grid->width - 1; i++)
	{
		for(j = 0; j < grid->height - 1; j++)
		{
			p1 = grid->points[i][j];
			p2 = grid->points[i + 1][j];
			p3 = grid->points[i + 1][j + 1];
			gridPlanes[i][j][0] = CM_FindPlane(p1, p2, p3);

			p1 = grid->points[i + 1][j + 1];
			p2 = grid->points[i][j + 1];
			p3 = grid->points[i][j];
			gridPlanes[i][j][1] = CM_FindPlane(p1, p2, p3);
		}
	}

	// create the borders for each facet
	for(i = 0; i < grid->width - 1; i++)
	{
		for(j = 0; j < grid->height - 1; j++)
		{

			borders[EN_TOP] = -1;
			if(j > 0)
			{
				borders[EN_TOP] = gridPlanes[i][j - 1][1];
			}
			else if(grid->wrapHeight)
			{
				borders[EN_TOP] = gridPlanes[i][grid->height - 2][1];
			}
			noAdjust[EN_TOP] = (borders[EN_TOP] == gridPlanes[i][j][0]);
			if(borders[EN_TOP] == -1 || noAdjust[EN_TOP])
			{
				borders[EN_TOP] = CM_EdgePlaneNum(grid, gridPlanes, i, j, 0);
			}

			borders[EN_BOTTOM] = -1;
			if(j < grid->height - 2)
			{
				borders[EN_BOTTOM] = gridPlanes[i][j + 1][0];
			}
			else if(grid->wrapHeight)
			{
				borders[EN_BOTTOM] = gridPlanes[i][0][0];
			}
			noAdjust[EN_BOTTOM] = (borders[EN_BOTTOM] == gridPlanes[i][j][1]);
			if(borders[EN_BOTTOM] == -1 || noAdjust[EN_BOTTOM])
			{
				borders[EN_BOTTOM] = CM_EdgePlaneNum(grid, gridPlanes, i, j, 2);
			}

			borders[EN_LEFT] = -1;
			if(i > 0)
			{
				borders[EN_LEFT] = gridPlanes[i - 1][j][0];
			}
			else if(grid->wrapWidth)
			{
				borders[EN_LEFT] = gridPlanes[grid->width - 2][j][0];
			}
			noAdjust[EN_LEFT] = (borders[EN_LEFT] == gridPlanes[i][j][1]);
			if(borders[EN_LEFT] == -1 || noAdjust[EN_LEFT])
			{
				borders[EN_LEFT] = CM_EdgePlaneNum(grid, gridPlanes, i, j, 3);
			}

			borders[EN_RIGHT] = -1;
			if(i < grid->width - 2)
			{
				borders[EN_RIGHT] = gridPlanes[i + 1][j][1];
			}
			else if(grid->wrapWidth)
			{
				borders[EN_RIGHT] = gridPlanes[0][j][1];
			}
			noAdjust[EN_RIGHT] = (borders[EN_RIGHT] == gridPlanes[i][j][0]);
			if(borders[EN_RIGHT] == -1 || noAdjust[EN_RIGHT])
			{
				borders[EN_RIGHT] = CM_EdgePlaneNum(grid, gridPlanes, i, j, 1);
			}

			if(numFacets == MAX_FACETS)
			{
				Com_Error(ERR_DROP, "MAX_FACETS");
			}
			facet = &facets[numFacets];
			Com_Memset(facet, 0, sizeof(*facet));

			if(gridPlanes[i][j][0] == gridPlanes[i][j][1])
			{
				if(gridPlanes[i][j][0] == -1)
				{
					continue;	// degenrate
				}
				facet->surfacePlane = gridPlanes[i][j][0];
				facet->numBorders = 4;
				facet->borderPlanes[0] = borders[EN_TOP];
				facet->borderNoAdjust[0] = noAdjust[EN_TOP];
				facet->borderPlanes[1] = borders[EN_RIGHT];
				facet->borderNoAdjust[1] = noAdjust[EN_RIGHT];
				facet->borderPlanes[2] = borders[EN_BOTTOM];
				facet->borderNoAdjust[2] = noAdjust[EN_BOTTOM];
				facet->borderPlanes[3] = borders[EN_LEFT];
				facet->borderNoAdjust[3] = noAdjust[EN_LEFT];
				CM_SetBorderInward(facet, grid, gridPlanes, i, j, -1);
				if(CM_ValidateFacet(facet))
				{
					CM_AddFacetBevels(facet);
					numFacets++;
				}
			}
			else
			{
				// two seperate triangles
				facet->surfacePlane = gridPlanes[i][j][0];
				facet->numBorders = 3;
				facet->borderPlanes[0] = borders[EN_TOP];
				facet->borderNoAdjust[0] = noAdjust[EN_TOP];
				facet->borderPlanes[1] = borders[EN_RIGHT];
				facet->borderNoAdjust[1] = noAdjust[EN_RIGHT];
				facet->borderPlanes[2] = gridPlanes[i][j][1];
				if(facet->borderPlanes[2] == -1)
				{
					facet->borderPlanes[2] = borders[EN_BOTTOM];
					if(facet->borderPlanes[2] == -1)
					{
						facet->borderPlanes[2] = CM_EdgePlaneNum(grid, gridPlanes, i, j, 4);
					}
				}
				CM_SetBorderInward(facet, grid, gridPlanes, i, j, 0);
				if(CM_ValidateFacet(facet))
				{
					CM_AddFacetBevels(facet);
					numFacets++;
				}

				if(numFacets == MAX_FACETS)
				{
					Com_Error(ERR_DROP, "MAX_FACETS");
				}
				facet = &facets[numFacets];
				Com_Memset(facet, 0, sizeof(*facet));

				facet->surfacePlane = gridPlanes[i][j][1];
				facet->numBorders = 3;
				facet->borderPlanes[0] = borders[EN_BOTTOM];
				facet->borderNoAdjust[0] = noAdjust[EN_BOTTOM];
				facet->borderPlanes[1] = borders[EN_LEFT];
				facet->borderNoAdjust[1] = noAdjust[EN_LEFT];
				facet->borderPlanes[2] = gridPlanes[i][j][0];
				if(facet->borderPlanes[2] == -1)
				{
					facet->borderPlanes[2] = borders[EN_TOP];
					if(facet->borderPlanes[2] == -1)
					{
						facet->borderPlanes[2] = CM_EdgePlaneNum(grid, gridPlanes, i, j, 5);
					}
				}
				CM_SetBorderInward(facet, grid, gridPlanes, i, j, 1);
				if(CM_ValidateFacet(facet))
				{
					CM_AddFacetBevels(facet);
					numFacets++;
				}
			}
		}
	}

	// copy the results out
	pf->numPlanes = numPlanes;
	pf->numFacets = numFacets;
	pf->facets = Hunk_Alloc(numFacets * sizeof(*pf->facets), h_high);
	Com_Memcpy(pf->facets, facets, numFacets * sizeof(*pf->facets));
	pf->planes = Hunk_Alloc(numPlanes * sizeof(*pf->planes), h_high);
	Com_Memcpy(pf->planes, planes, numPlanes * sizeof(*pf->planes));
}


/*
===================
CM_GeneratePatchCollide

Creates an internal structure that will be used to perform
collision detection with a patch mesh.

Points is packed as concatenated rows.
===================
*/
struct patchCollide_s *CM_GeneratePatchCollide(int width, int height, vec3_t * points)
{
	patchCollide_t *pf;
	cGrid_t         grid;
	int             i, j;

	if(width <= 2 || height <= 2 || !points)
	{
		Com_Error(ERR_DROP, "CM_GeneratePatchFacets: bad parameters: (%i, %i, %p)", width, height, points);
	}

	if(!(width & 1) || !(height & 1))
	{
		Com_Error(ERR_DROP, "CM_GeneratePatchFacets: even sizes are invalid for quadratic meshes");
	}

	if(width > MAX_GRID_SIZE || height > MAX_GRID_SIZE)
	{
		Com_Error(ERR_DROP, "CM_GeneratePatchFacets: source is > MAX_GRID_SIZE");
	}

	// build a grid
	grid.width = width;
	grid.height = height;
	grid.wrapWidth = qfalse;
	grid.wrapHeight = qfalse;
	for(i = 0; i < width; i++)
	{
		for(j = 0; j < height; j++)
		{
			VectorCopy(points[j * width + i], grid.points[i][j]);
		}
	}

	// subdivide the grid
	CM_SetGridWrapWidth(&grid);
	CM_SubdivideGridColumns(&grid);
	CM_RemoveDegenerateColumns(&grid);

	CM_TransposeGrid(&grid);

	CM_SetGridWrapWidth(&grid);
	CM_SubdivideGridColumns(&grid);
	CM_RemoveDegenerateColumns(&grid);

	// we now have a grid of points exactly on the curve
	// the aproximate surface defined by these points will be
	// collided against
	pf = Hunk_Alloc(sizeof(*pf), h_high);
	ClearBounds(pf->bounds[0], pf->bounds[1]);
	for(i = 0; i < grid.width; i++)
	{
		for(j = 0; j < grid.height; j++)
		{
			AddPointToBounds(grid.points[i][j], pf->bounds[0], pf->bounds[1]);
		}
	}

	c_totalPatchBlocks += (grid.width - 1) * (grid.height - 1);

	// generate a bsp tree for the surface
	CM_PatchCollideFromGrid(&grid, pf);

	// expand by one unit for epsilon purposes
	pf->bounds[0][0] -= 1;
	pf->bounds[0][1] -= 1;
	pf->bounds[0][2] -= 1;

	pf->bounds[1][0] += 1;
	pf->bounds[1][1] += 1;
	pf->bounds[1][2] += 1;

	return pf;
}

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

TRACE TESTING

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

/*
====================
CM_TracePointThroughPatchCollide

  special case for point traces because the patch collide "brushes" have no volume
====================
*/
void CM_TracePointThroughPatchCollide(traceWork_t * tw, const struct patchCollide_s *pc)
{
	qboolean        frontFacing[MAX_PATCH_PLANES];
	float           intersection[MAX_PATCH_PLANES];
	float           intersect;
	const patchPlane_t *planes;
	const facet_t  *facet;
	int             i, j, k;
	float           offset;
	float           d1, d2;

#ifndef BSPC
	static cvar_t  *cv;
#endif							//BSPC

#ifndef BSPC
	if(!cm_playerCurveClip->integer || !tw->isPoint)
	{
		return;
	}
#endif

	// determine the trace's relationship to all planes
	planes = pc->planes;
	for(i = 0; i < pc->numPlanes; i++, planes++)
	{
		offset = DotProduct(tw->offsets[planes->signbits], planes->plane);
		d1 = DotProduct(tw->start, planes->plane) - planes->plane[3] + offset;
		d2 = DotProduct(tw->end, planes->plane) - planes->plane[3] + offset;
		if(d1 <= 0)
		{
			frontFacing[i] = qfalse;
		}
		else
		{
			frontFacing[i] = qtrue;
		}
		if(d1 == d2)
		{
			intersection[i] = 99999;
		}
		else
		{
			intersection[i] = d1 / (d1 - d2);
			if(intersection[i] <= 0)
			{
				intersection[i] = 99999;
			}
		}
	}


	// see if any of the surface planes are intersected
	facet = pc->facets;
	for(i = 0; i < pc->numFacets; i++, facet++)
	{
		if(!frontFacing[facet->surfacePlane])
		{
			continue;
		}
		intersect = intersection[facet->surfacePlane];
		if(intersect < 0)
		{
			continue;			// surface is behind the starting point
		}
		if(intersect > tw->trace.fraction)
		{
			continue;			// already hit something closer
		}
		for(j = 0; j < facet->numBorders; j++)
		{
			k = facet->borderPlanes[j];
			if(frontFacing[k] ^ facet->borderInward[j])
			{
				if(intersection[k] > intersect)
				{
					break;
				}
			}
			else
			{
				if(intersection[k] < intersect)
				{
					break;
				}
			}
		}
		if(j == facet->numBorders)
		{
			// we hit this facet
#ifndef BSPC
			if(!cv)
			{
				cv = Cvar_Get("r_debugSurfaceUpdate", "1", 0);
			}
			if(cv->integer)
			{
				debugPatchCollide = pc;
				debugFacet = facet;
			}
#endif							//BSPC
			planes = &pc->planes[facet->surfacePlane];

			// calculate intersection with a slight pushoff
			offset = DotProduct(tw->offsets[planes->signbits], planes->plane);
			d1 = DotProduct(tw->start, planes->plane) - planes->plane[3] + offset;
			d2 = DotProduct(tw->end, planes->plane) - planes->plane[3] + offset;
			tw->trace.fraction = (d1 - SURFACE_CLIP_EPSILON) / (d1 - d2);

			if(tw->trace.fraction < 0)
			{
				tw->trace.fraction = 0;
			}

			VectorCopy(planes->plane, tw->trace.plane.normal);
			tw->trace.plane.dist = planes->plane[3];
		}
	}
}

/*
====================
CM_CheckFacetPlane
====================
*/
int CM_CheckFacetPlane(float *plane, vec3_t start, vec3_t end, float *enterFrac, float *leaveFrac, int *hit)
{
	float           d1, d2, f;

	*hit = qfalse;

	d1 = DotProduct(start, plane) - plane[3];
	d2 = DotProduct(end, plane) - plane[3];

	// if completely in front of face, no intersection with the entire facet
	if(d1 > 0 && (d2 >= SURFACE_CLIP_EPSILON || d2 >= d1))
	{
		return qfalse;
	}

	// if it doesn't cross the plane, the plane isn't relevent
	if(d1 <= 0 && d2 <= 0)
	{
		return qtrue;
	}

	// crosses face
	if(d1 > d2)
	{							// enter
		f = (d1 - SURFACE_CLIP_EPSILON) / (d1 - d2);
		if(f < 0)
		{
			f = 0;
		}
		//always favor previous plane hits and thus also the surface plane hit
		if(f > *enterFrac)
		{
			*enterFrac = f;
			*hit = qtrue;
		}
	}
	else
	{							// leave
		f = (d1 + SURFACE_CLIP_EPSILON) / (d1 - d2);
		if(f > 1)
		{
			f = 1;
		}
		if(f < *leaveFrac)
		{
			*leaveFrac = f;
		}
	}
	return qtrue;
}

/*
====================
CM_TraceThroughPatchCollide
====================
*/
void CM_TraceThroughPatchCollide(traceWork_t * tw, const struct patchCollide_s *pc)
{
	int             i, j, hit, hitnum;
	float           offset, enterFrac, leaveFrac, t;
	patchPlane_t   *planes;
	facet_t        *facet;
	float           plane[4] = {0, 0, 0, 0}, bestplane[4] =	{0, 0, 0, 0};
	vec3_t          startp, endp;

#ifndef BSPC
	static cvar_t  *cv;
#endif							//BSPC

	if(tw->isPoint)
	{
		CM_TracePointThroughPatchCollide(tw, pc);
		return;
	}

	facet = pc->facets;
	for(i = 0; i < pc->numFacets; i++, facet++)
	{
		enterFrac = -1.0;
		leaveFrac = 1.0;
		hitnum = -1;
		//
		planes = &pc->planes[facet->surfacePlane];
		VectorCopy(planes->plane, plane);
		plane[3] = planes->plane[3];
		if(tw->sphere.use)
		{
			// adjust the plane distance apropriately for radius
			plane[3] += tw->sphere.radius;

			// find the closest point on the capsule to the plane
			t = DotProduct(plane, tw->sphere.offset);
			if(t > 0.0f)
			{
				VectorSubtract(tw->start, tw->sphere.offset, startp);
				VectorSubtract(tw->end, tw->sphere.offset, endp);
			}
			else
			{
				VectorAdd(tw->start, tw->sphere.offset, startp);
				VectorAdd(tw->end, tw->sphere.offset, endp);
			}
		}
		else
		{
			offset = DotProduct(tw->offsets[planes->signbits], plane);
			plane[3] -= offset;
			VectorCopy(tw->start, startp);
			VectorCopy(tw->end, endp);
		}

		if(!CM_CheckFacetPlane(plane, startp, endp, &enterFrac, &leaveFrac, &hit))
		{
			continue;
		}
		if(hit)
		{
			VectorCopy4(plane, bestplane);
		}

		for(j = 0; j < facet->numBorders; j++)
		{
			planes = &pc->planes[facet->borderPlanes[j]];
			if(facet->borderInward[j])
			{
				VectorNegate(planes->plane, plane);
				plane[3] = -planes->plane[3];
			}
			else
			{
				VectorCopy(planes->plane, plane);
				plane[3] = planes->plane[3];
			}
			if(tw->sphere.use)
			{
				// adjust the plane distance apropriately for radius
				plane[3] += tw->sphere.radius;

				// find the closest point on the capsule to the plane
				t = DotProduct(plane, tw->sphere.offset);
				if(t > 0.0f)
				{
					VectorSubtract(tw->start, tw->sphere.offset, startp);
					VectorSubtract(tw->end, tw->sphere.offset, endp);
				}
				else
				{
					VectorAdd(tw->start, tw->sphere.offset, startp);
					VectorAdd(tw->end, tw->sphere.offset, endp);
				}
			}
			else
			{
				// NOTE: this works even though the plane might be flipped because the bbox is centered
				offset = DotProduct(tw->offsets[planes->signbits], plane);
				plane[3] += fabs(offset);
				VectorCopy(tw->start, startp);
				VectorCopy(tw->end, endp);
			}

			if(!CM_CheckFacetPlane(plane, startp, endp, &enterFrac, &leaveFrac, &hit))
			{
				break;
			}
			if(hit)
			{
				hitnum = j;
				VectorCopy4(plane, bestplane);
			}
		}
		if(j < facet->numBorders)
			continue;
		//never clip against the back side
		if(hitnum == facet->numBorders - 1)
			continue;

		if(enterFrac < leaveFrac && enterFrac >= 0)
		{
			if(enterFrac < tw->trace.fraction)
			{
				if(enterFrac < 0)
				{
					enterFrac = 0;
				}
#ifndef BSPC
				if(!cv)
				{
					cv = Cvar_Get("r_debugSurfaceUpdate", "1", 0);
				}
				if(cv && cv->integer)
				{
					debugPatchCollide = pc;
					debugFacet = facet;
				}
#endif							//BSPC

				tw->trace.fraction = enterFrac;
				VectorCopy(bestplane, tw->trace.plane.normal);
				tw->trace.plane.dist = bestplane[3];
			}
		}
	}
}


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

POSITION TEST

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

/*
====================
CM_PositionTestInPatchCollide
====================
*/
qboolean CM_PositionTestInPatchCollide(traceWork_t * tw, const struct patchCollide_s *pc)
{
	int             i, j;
	float           offset, t;
	patchPlane_t   *planes;
	facet_t        *facet;
	float           plane[4];
	vec3_t          startp;

	if(tw->isPoint)
	{
		return qfalse;
	}
	//
	facet = pc->facets;
	for(i = 0; i < pc->numFacets; i++, facet++)
	{
		planes = &pc->planes[facet->surfacePlane];
		VectorCopy(planes->plane, plane);
		plane[3] = planes->plane[3];
		if(tw->sphere.use)
		{
			// adjust the plane distance apropriately for radius
			plane[3] += tw->sphere.radius;

			// find the closest point on the capsule to the plane
			t = DotProduct(plane, tw->sphere.offset);
			if(t > 0)
			{
				VectorSubtract(tw->start, tw->sphere.offset, startp);
			}
			else
			{
				VectorAdd(tw->start, tw->sphere.offset, startp);
			}
		}
		else
		{
			offset = DotProduct(tw->offsets[planes->signbits], plane);
			plane[3] -= offset;
			VectorCopy(tw->start, startp);
		}

		if(DotProduct(plane, startp) - plane[3] > 0.0f)
		{
			continue;
		}

		for(j = 0; j < facet->numBorders; j++)
		{
			planes = &pc->planes[facet->borderPlanes[j]];
			if(facet->borderInward[j])
			{
				VectorNegate(planes->plane, plane);
				plane[3] = -planes->plane[3];
			}
			else
			{
				VectorCopy(planes->plane, plane);
				plane[3] = planes->plane[3];
			}
			if(tw->sphere.use)
			{
				// adjust the plane distance apropriately for radius
				plane[3] += tw->sphere.radius;

				// find the closest point on the capsule to the plane
				t = DotProduct(plane, tw->sphere.offset);
				if(t > 0.0f)
				{
					VectorSubtract(tw->start, tw->sphere.offset, startp);
				}
				else
				{
					VectorAdd(tw->start, tw->sphere.offset, startp);
				}
			}
			else
			{
				// NOTE: this works even though the plane might be flipped because the bbox is centered
				offset = DotProduct(tw->offsets[planes->signbits], plane);
				plane[3] += fabs(offset);
				VectorCopy(tw->start, startp);
			}

			if(DotProduct(plane, startp) - plane[3] > 0.0f)
			{
				break;
			}
		}
		if(j < facet->numBorders)
		{
			continue;
		}
		// inside this patch facet
		return qtrue;
	}
	return qfalse;
}

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

DEBUGGING

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


/*
==================
CM_DrawDebugSurface

Called from the renderer
==================
*/
#ifndef BSPC
void            BotDrawDebugPolygons(void (*drawPoly) (int color, int numPoints, float *points), int value);
#endif

void CM_DrawDebugSurface(void (*drawPoly) (int color, int numPoints, float *points))
{
	static cvar_t  *cv;

#ifndef BSPC
	static cvar_t  *cv2;
#endif
	const patchCollide_t *pc;
	facet_t        *facet;
	winding_t      *w;
	int             i, j, k, n;
	int             curplanenum, planenum, curinward, inward;
	float           plane[4];
	vec3_t          mins = { -15, -15, -28 }, maxs =
	{
	15, 15, 28};
	//vec3_t mins = {0, 0, 0}, maxs = {0, 0, 0};
	vec3_t          v1, v2;

#ifndef BSPC
	if(!cv2)
	{
		cv2 = Cvar_Get("r_debugSurface", "0", 0);
	}

	if(cv2->integer != 1)
	{
		BotDrawDebugPolygons(drawPoly, cv2->integer);
		return;
	}
#endif

	if(!debugPatchCollide)
	{
		return;
	}

#ifndef BSPC
	if(!cv)
	{
		cv = Cvar_Get("cm_debugSize", "2", 0);
	}
#endif
	pc = debugPatchCollide;

	for(i = 0, facet = pc->facets; i < pc->numFacets; i++, facet++)
	{

		for(k = 0; k < facet->numBorders + 1; k++)
		{
			//
			if(k < facet->numBorders)
			{
				planenum = facet->borderPlanes[k];
				inward = facet->borderInward[k];
			}
			else
			{
				planenum = facet->surfacePlane;
				inward = qfalse;
				//continue;
			}

			VectorCopy4(pc->planes[planenum].plane, plane);

			//planenum = facet->surfacePlane;
			if(inward)
			{
				VectorSubtract(vec3_origin, plane, plane);
				plane[3] = -plane[3];
			}

			plane[3] += cv->value;
			//*
			for(n = 0; n < 3; n++)
			{
				if(plane[n] > 0)
					v1[n] = maxs[n];
				else
					v1[n] = mins[n];
			}					//end for
			VectorNegate(plane, v2);
			plane[3] += fabs(DotProduct(v1, v2));
			//*/

			w = BaseWindingForPlane(plane, plane[3]);
			for(j = 0; j < facet->numBorders + 1 && w; j++)
			{
				//
				if(j < facet->numBorders)
				{
					curplanenum = facet->borderPlanes[j];
					curinward = facet->borderInward[j];
				}
				else
				{
					curplanenum = facet->surfacePlane;
					curinward = qfalse;
					//continue;
				}
				//
				if(curplanenum == planenum)
					continue;

				VectorCopy4(pc->planes[curplanenum].plane, plane);
				if(!curinward)
				{
					VectorSubtract(vec3_origin, plane, plane);
					plane[3] = -plane[3];
				}
				//          if ( !facet->borderNoAdjust[j] ) {
				plane[3] -= cv->value;
				//          }
				for(n = 0; n < 3; n++)
				{
					if(plane[n] > 0)
						v1[n] = maxs[n];
					else
						v1[n] = mins[n];
				}				//end for
				VectorNegate(plane, v2);
				plane[3] -= fabs(DotProduct(v1, v2));

				ChopWindingInPlace(&w, plane, plane[3], 0.1f);
			}
			if(w)
			{
				if(facet == debugFacet)
				{
					drawPoly(4, w->numpoints, w->p[0]);
					//Com_Printf("blue facet has %d border planes\n", facet->numBorders);
				}
				else
				{
					drawPoly(1, w->numpoints, w->p[0]);
				}
				FreeWinding(w);
			}
			else
				Com_Printf("winding chopped away by border planes\n");
		}
	}

	// draw the debug block
	{
		vec3_t          v[3];

		VectorCopy(debugBlockPoints[0], v[0]);
		VectorCopy(debugBlockPoints[1], v[1]);
		VectorCopy(debugBlockPoints[2], v[2]);
		drawPoly(2, 3, v[0]);

		VectorCopy(debugBlockPoints[2], v[0]);
		VectorCopy(debugBlockPoints[3], v[1]);
		VectorCopy(debugBlockPoints[0], v[2]);
		drawPoly(2, 3, v[0]);
	}

#if 0
	vec3_t          v[4];

	v[0][0] = pc->bounds[1][0];
	v[0][1] = pc->bounds[1][1];
	v[0][2] = pc->bounds[1][2];

	v[1][0] = pc->bounds[1][0];
	v[1][1] = pc->bounds[0][1];
	v[1][2] = pc->bounds[1][2];

	v[2][0] = pc->bounds[0][0];
	v[2][1] = pc->bounds[0][1];
	v[2][2] = pc->bounds[1][2];

	v[3][0] = pc->bounds[0][0];
	v[3][1] = pc->bounds[1][1];
	v[3][2] = pc->bounds[1][2];

	drawPoly(4, v[0]);
#endif
}
