/*==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.

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 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/>.

You can contact Cyan Worlds, Inc. by email legal@cyan.com
 or by snail mail at:
      Cyan Worlds, Inc.
      14617 N Newport Hwy
      Mead, WA   99021

*==LICENSE==*/
#ifndef PLGRASSSHADERMOD_INC
#define PLGRASSSHADERMOD_INC

#include "pnModifier/plModifier.h"

class plSceneObject;
class hsGMaterial;
class plShader;

class plGrassWave
{
public:
    plGrassWave() : fDistX(0.F), fDistY(0.F), fDistZ(0.F), fDirX(0.F), fDirY(0.F), fSpeed(0.F) {}

    hsScalar fDistX;
    hsScalar fDistY;
    hsScalar fDistZ;
    hsScalar fDirX;
    hsScalar fDirY;
    hsScalar fSpeed;

    void Write(hsStream *s);
    void Read(hsStream *s);
};

class plGrassShaderMod : public plModifier
{
public:
    plGrassShaderMod() : fTarget(nil), fMaterial(nil), fVShader(nil), fPShader(nil) {}
    ~plGrassShaderMod();

    void ResetWaves();
    void RefreshWaves();

    virtual int GetNumTargets() const { return fTarget ? 1 : 0; }
    virtual plSceneObject* GetTarget(int w) const { return fTarget; }
    virtual void AddTarget(plSceneObject *object);
    virtual void RemoveTarget(plSceneObject *object);

    virtual hsBool MsgReceive(plMessage *msg);

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

    CLASSNAME_REGISTER( plGrassShaderMod );
    GETINTERFACE_ANY( plGrassShaderMod, plModifier );

    enum {
        kRefGrassVS,
        kRefGrassPS,
        kRefMaterial,
    };

    enum {
        kNumWaves = 4,
    };

    plGrassWave fWaves[kNumWaves];

protected:
    virtual hsBool IEval(double secs, hsScalar del, UInt32 dirty);
    virtual void IApplyDynamic() {};    // dummy function required by base class
    void ISetupShaders();
    void IRefreshWaves(plShader *vShader);

    plSceneObject *fTarget;
    hsGMaterial *fMaterial;
    plShader *fVShader;
    plShader *fPShader;
};

namespace plGrassVS
{
    enum {
        kLocalToNDC     = 0,
        kNumericConsts  = 4,
        kAppConsts      = 5,
        kPiConsts       = 6,
        kSinConsts      = 7,
        kWaveDistX      = 8,
        kWaveDistY      = 9,
        kWaveDistZ      = 10,
        kWaveDirX       = 11,
        kWaveDirY       = 12,
        kWaveSpeed      = 13,

        kNumConsts      = 14,
    };
};

#endif // PLGRASSSHADERMOD