polylib.h #1

//========= Copyright  1996-2005, Valve Corporation, All rights reserved. ============//
//
// Purpose: 
//
// $Workfile:     $
// $Date:         $
//
//-----------------------------------------------------------------------------
// $Log: $
//
// $NoKeywords: $
//=============================================================================//

#ifndef POLYLIB_H
#define POLYLIB_H
#pragma once

#ifndef MATHLIB_H
#include "mathlib.h"
#endif

struct winding_t
{
	int		numpoints;
	Vector	*p;		// variable sized
	int		maxpoints;
	winding_t *next;
};

#define	MAX_POINTS_ON_WINDING	64

// you can define on_epsilon in the makefile as tighter
// point on plane side epsilon
// todo: need a world-space epsilon, a lightmap-space epsilon, and a texture space epsilon
// or at least convert from a world-space epsilon to lightmap and texture space epsilons
#ifndef	ON_EPSILON
#define	ON_EPSILON	0.1
#endif


winding_t	*AllocWinding (int points);
vec_t	WindingArea (winding_t *w);
void	WindingCenter (winding_t *w, Vector &center);
vec_t	WindingAreaAndBalancePoint( winding_t *w, Vector &center );
void	ClipWindingEpsilon (winding_t *in, const Vector &normal, vec_t dist, 
				vec_t epsilon, winding_t **front, winding_t **back);

// translates everything by offset, then does the clip, then translates back (to keep precision)
void ClipWindingEpsilon_Offset( winding_t *in, const Vector &normal, vec_t dist, vec_t epsilon, winding_t **front, winding_t **back, const Vector &offset );

void	ClassifyWindingEpsilon( winding_t *in, const Vector &normal, vec_t dist, 
				vec_t epsilon, winding_t **front, winding_t **back, winding_t **on);
void	ClassifyWindingEpsilon_Offset( winding_t *in, const Vector &normal, vec_t dist, 
				vec_t epsilon, winding_t **front, winding_t **back, winding_t **on, const Vector &offset);

winding_t	*ChopWinding (winding_t *in, const Vector &normal, vec_t dist);
winding_t	*CopyWinding (winding_t *w);
winding_t	*ReverseWinding (winding_t *w);
winding_t	*BaseWindingForPlane (const Vector &normal, vec_t dist);
void	CheckWinding (winding_t *w);
void	WindingPlane (winding_t *w, Vector &normal, vec_t *dist);
void	RemoveColinearPoints (winding_t *w);
int		WindingOnPlaneSide (winding_t *w, const Vector &normal, vec_t dist);
void	FreeWinding (winding_t *w);
void	WindingBounds (winding_t *w, Vector &mins, Vector &maxs);

void	ChopWindingInPlace (winding_t **w, const Vector &normal, vec_t dist, vec_t epsilon);
// frees the original if clipped

bool PointInWinding( Vector const &pt, winding_t *pWinding );

// translates a winding by offset
void TranslateWinding( winding_t *pWinding, const Vector &offset );

void pw(winding_t *w);


#endif // POLYLIB_H