GroundFog.h

/*
This file is part of Caelum.
See http://www.ogre3d.org/wiki/index.php/Caelum 

Copyright (c) 2006-2007 Caelum team. See Contributors.txt for details.

Caelum is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Caelum 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License
along with Caelum. If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef GROUNDFOG_H
#define GROUNDFOG_H

#include "CaelumPrerequisites.h"
#include "CameraBoundElement.h"
#include "PrivatePtr.h"
#include "FastGpuParamRef.h"

namespace Caelum
{
    class CAELUM_EXPORT GroundFog: public CameraBoundElement
    {
    public:
        static const Ogre::String DEFAULT_PASS_NAME;

        GroundFog (Ogre::SceneManager *scene,
            Ogre::SceneNode *caelumRootNode,
            const Ogre::String &domeMaterialName = "CaelumGroundFogDome",
            const Ogre::String &domeEntityName = "CaelumGroundFogDome");

        virtual ~GroundFog ();

        typedef std::set<Ogre::Pass *> PassSet;

        PassSet& getPasses();

        const PassSet& getPasses () const;

        void findFogPassesByName (const Ogre::String& passName = DEFAULT_PASS_NAME);

        void setDensity (Ogre::Real density);

        Ogre::Real getDensity () const;

        void setColour (const Ogre::ColourValue &colour);

        const Ogre::ColourValue getColour () const;

        void setVerticalDecay (Ogre::Real verticalDecay);

        Ogre::Real getVerticalDecay () const;

        void setGroundLevel (Ogre::Real GroundLevela);

        Ogre::Real getGroundLevel () const;

        void forceUpdate ();

    private:
        Ogre::Real mDensity;

        Ogre::Real mVerticalDecay;

        Ogre::Real mGroundLevel;

        Ogre::ColourValue mFogColour;

    private:
        Ogre::SceneManager* mScene;

        PrivateMaterialPtr mDomeMaterial;
        
        PrivateSceneNodePtr mDomeNode;

        PrivateEntityPtr mDomeEntity;

        // Called whenever something changes to update the sky dome.
        void updateSkyFogging();

    protected:
        virtual void setFarRadius (Ogre::Real radius);

    public:
        virtual void notifyCameraChanged (Ogre::Camera *cam);

        void setQueryFlags (uint flags) { mDomeEntity->setQueryFlags (flags); }
        uint getQueryFlags () const { return mDomeEntity->getQueryFlags (); }
        void setVisibilityFlags (uint flags) { mDomeEntity->setVisibilityFlags (flags); }
        uint getVisibilityFlags () const { return mDomeEntity->getVisibilityFlags (); }

    private:
        PassSet mPasses;

        struct FogParamsBase
        {
            void setup(Ogre::GpuProgramParametersSharedPtr fpParams);

            Ogre::GpuProgramParametersSharedPtr fpParams;

            FastGpuParamRef fogDensity;
            FastGpuParamRef fogColour;
            FastGpuParamRef fogVerticalDecay;
            FastGpuParamRef fogGroundLevel;

        };

        struct DomeFogParams: public FogParamsBase {
            void setup(Ogre::GpuProgramParametersSharedPtr fpParams);
            FastGpuParamRef cameraHeight;
        } mDomeParams;

        struct PassFogParams: public FogParamsBase {
            PassFogParams(Ogre::GpuProgramParametersSharedPtr fpParams) { setup(fpParams); }

            static inline bool lessThanByParams(const PassFogParams& a, const PassFogParams& b) {
                return a.fpParams.get() <= b.fpParams.get();
            }

            static inline bool equalByParams(const PassFogParams& a, const PassFogParams& b) {
                return a.fpParams.get() == b.fpParams.get();
            }
        };

        typedef std::vector<PassFogParams> PassFogParamsVector;
        PassFogParamsVector mPassFogParams;

        void updatePassFogParams();
    };
}

#endif //GROUNDFOG_H