// NeL - MMORPG Framework <http://dev.ryzom.com/projects/nel/>
// Copyright (C) 2010  Winch Gate Property Limited
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// This program 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

#ifndef NL_ZONE_SMOOTHER_H
#define NL_ZONE_SMOOTHER_H

#include "nel/misc/types_nl.h"
#include "nel/3d/zone.h"
#include "nel/misc/common.h"
#include <map>


namespace NL3D
{


// ***************************************************************************
/**
 * A class used to make Bezier patch of zones G1.
 * \author Lionel Berenguier
 * \author Nevrax France
 * \date 2000
 */
class CZoneSmoother
{
public:
	struct	CZoneInfo
	{
		/// Id of the zone.
		uint16 ZoneId;

		/// A ptr on the array of patchs of the zone.
		std::vector<CPatchInfo>		*Patchs;

		CZoneInfo()
		{
			ZoneId= 0;
			Patchs= NULL;
		}
	};

public:
	/// Constructor
	CZoneSmoother() {}


	/**
	 * Smooth the tangents of those zones. Zones must be correclty welded.
	 * Only all patchs of zones[0] are parsed. But other zones may be modified on their edge (so you must save them).
	 *
	 * NB: tangent smoothing is only done on bind 1/1.
	 *
	 * \param zones The 0 is the center zone to be computed. Other are the 4 zones around (no special order needed).
	 *	Doesn't matter if zones[i].Patchs is NULL. Also, if a neighbor patch is not found on a edge, then no error is
	 *  generated: this patch edge is not modified.
	 *	nlstop if zones[0]==NULL.
	 * \param angleThreshold if angle beetween (patch_interior - tangent) and (neighbor_patch_interior - tangent) is
	 *	above angleThreshold, no smooth is done on this tangent. Default: 30deg.
	 * \param continuityC1. when a smooth is done on a tangent, tangent is forced such that the 2 interiors and the
	 *	tangent are colinear, so continuity G1 is assured. if continuityC1 is true, then tangent is set to the middle of
	 *	the interiors (continuity C1). If false, tangent is setup so that previous distance ratio are kept.
	 *
	 */
	void			smoothTangents(CZoneInfo zones[5], float angleThreshold= NLMISC::Pi/6, bool continuityC1= false);


private:
	typedef std::map<sint, CZoneInfo>	TZoneInfoMap;
	TZoneInfoMap		_Zones;
	float				_CosThreshold;
	bool				_ContinuityC1;

	// smoothTangent according to _CosThreshold and _ContinuityC1.
	bool		smoothTangent(const CVector &tgt, const CVector &int0, const CVector &int1, CVector &tgtres);

};


} // NL3D


#endif // NL_ZONE_SMOOTHER_H

/* End of zone_smoother.h */