/*==LICENSE==*

CyanWorlds.com Engine - MMOG client, server and tools
Copyright (C) 2011 Cyan Worlds, Inc.

This program 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.

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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 this program. If not, see <http://www.gnu.org/licenses/>.

Additional permissions under GNU GPL version 3 section 7

If you modify this Program, or any covered work, by linking or
combining it with any of RAD Game Tools Bink SDK, Autodesk 3ds Max SDK,
NVIDIA PhysX SDK, Microsoft DirectX SDK, OpenSSL library, Independent
JPEG Group JPEG library, Microsoft Windows Media SDK, or Apple QuickTime SDK
(or a modified version of those libraries),
containing parts covered by the terms of the Bink SDK EULA, 3ds Max EULA,
PhysX SDK EULA, DirectX SDK EULA, OpenSSL and SSLeay licenses, IJG
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 or by snail mail at:
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*==LICENSE==*/
#ifndef plParticleGenerator_inc
#define plParticleGenerator_inc

#include "hsGeometry3.h"
#include "../pnNetCommon/plSynchedValue.h"
class plParticleEmitter;
class plScalarController;

// This class is responsible for all the details of automatically generating particles for a plParticleEmitter.
// It gets a change in time, and must do whatever necessary to generate the appropriate number of particles
// for that timespan

class plParticleGenerator : public plCreatable
{

public:
	// returns false if it's done generating particles and is safe to delete.
	virtual hsBool AddAutoParticles(plParticleEmitter *emitter, float dt, UInt32 numForced = 0) = 0;

	virtual void UpdateParam(UInt32 paramID, hsScalar paramValue) = 0;

	CLASSNAME_REGISTER( plParticleGenerator );
	GETINTERFACE_ANY( plParticleGenerator, plCreatable );

	static const void ComputeDirection(float pitch, float yaw, hsVector3 &direction);
	static const void ComputePitchYaw(float &pitch, float &yaw, const hsVector3 &dir);
	static inline float GetRandomVar() { return 2.0f * (float)hsRand() / RAND_MAX - 1; } // returns a num between +/- 1.0
};

class plSimpleParticleGenerator : public plParticleGenerator
{
public:
	plSimpleParticleGenerator();
	~plSimpleParticleGenerator();
	void Init(hsScalar genLife, hsScalar partLifeMin, hsScalar partLifeMax, hsScalar particlesPerSecond, 
			  UInt32 numSources, hsPoint3 *pos, hsScalar *initPitch, hsScalar *initYaw, hsScalar angleRange,
			  hsScalar initVelMin, hsScalar initVelMax, hsScalar xSize, hsScalar ySize, 
			  hsScalar scaleMin, hsScalar scaleMax,
			  hsScalar massRange, hsScalar radsPerSecRange);

	CLASSNAME_REGISTER( plSimpleParticleGenerator );
	GETINTERFACE_ANY( plSimpleParticleGenerator, plParticleGenerator);
	
	virtual hsBool AddAutoParticles(plParticleEmitter *emitter, float dt, UInt32 numForced);
	virtual void UpdateParam(UInt32 paramID, hsScalar paramValue);

	virtual void Read(hsStream* s, hsResMgr *mgr); 
	virtual void Write(hsStream* s, hsResMgr *mgr);

protected:
	hsScalar fParticlesPerSecond;
	UInt32 fNumSources;
	hsPoint3 *fInitPos;
	hsScalar *fInitPitch, *fInitYaw;
	hsScalar fAngleRange;
	hsScalar fVelMin, fVelMax;
	hsScalar fXSize, fYSize, fScaleMin, fScaleMax;
	hsScalar fGenLife;  // How long shall we spit out particles from this location? When this time runs out, we stop
						// spitting particles, but we don't actually die until all of our particles die naturally.
						// (Even the ones that we feel are suffering needlessly.)

	hsScalar fPartLifeMin; // lifespan for the particles we generate
	hsScalar fPartLifeMax;

	hsScalar fPartInvMassMin;	// Doing a uniform variant over the inverse mass range (instead of over the mass range
	hsScalar fPartInvMassRange;	// and then inverting) will favor the low end of the mass range, but then again,
								// it's just a freaking game. Note though that fPartInvMassMin == 1.f / massMAX.

	hsScalar fPartRadsPerSecRange; // Zero means no rot, otherwise uniform random between [-range..range]

	hsScalar fParticleSum;

	enum
	{
		kImmortal	= 0x1,
		kDisabled	= 0x2,
	};
	UInt32 fMiscFlags;
};

class plOneTimeParticleGenerator : public plParticleGenerator
{
public:

	plOneTimeParticleGenerator();
	~plOneTimeParticleGenerator();
	void Init(hsScalar count, hsPoint3 *pointArray, hsVector3 *dirArray, 
			  hsScalar xSize, hsScalar ySize, hsScalar scaleMin, hsScalar scaleMax, hsScalar radsPerSec);

	CLASSNAME_REGISTER( plOneTimeParticleGenerator );
	GETINTERFACE_ANY( plOneTimeParticleGenerator, plParticleGenerator);

	virtual hsBool AddAutoParticles(plParticleEmitter *emitter, float dt, UInt32 numForced = 0);
	virtual void UpdateParam(UInt32 paramID, hsScalar paramValue) {}

	virtual void Read(hsStream* s, hsResMgr *mgr); 
	virtual void Write(hsStream* s, hsResMgr *mgr);

protected:
	hsScalar fCount;
	hsPoint3 *fPosition;
	hsVector3 *fDirection;
	hsScalar fXSize, fYSize, fScaleMin, fScaleMax;
	hsScalar fPartRadsPerSecRange; // Zero means no rot, otherwise uniform random between [-range..range]
};

#endif