StelSkyDrawer.hpp

/*
 * Stellarium
 * Copyright (C) 2007 Fabien Chereau
 *
 * 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 2
 * 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA  02110-1335, USA.
 */

#ifndef _STELSKYDRAWER_HPP_
#define _STELSKYDRAWER_HPP_

#include "RefractionExtinction.hpp"
#include "StelTextureTypes.hpp"
#include "StelProjectorType.hpp"
#include "VecMath.hpp"
#include "StelOpenGL.hpp"

#include <QObject>

class StelToneReproducer;
class StelCore;
class StelPainter;

struct RCMag
{
    float radius;
    float luminance;
};

class StelSkyDrawer : public QObject, protected QOpenGLFunctions
{
    Q_OBJECT

    Q_PROPERTY(double relativeStarScale READ getRelativeStarScale WRITE setRelativeStarScale NOTIFY relativeStarScaleChanged)
    Q_PROPERTY(double absoluteStarScale READ getAbsoluteStarScale WRITE setAbsoluteStarScale NOTIFY absoluteStarScaleChanged)
    Q_PROPERTY(double twinkleAmount READ getTwinkleAmount WRITE setTwinkleAmount NOTIFY twinkleAmountChanged)
    Q_PROPERTY(bool flagTwinkle READ getFlagTwinkle WRITE setFlagTwinkle NOTIFY flagTwinkleChanged)
    Q_PROPERTY(int bortleScaleIndex READ getBortleScaleIndex WRITE setBortleScaleIndex NOTIFY bortleScaleIndexChanged)

    Q_PROPERTY(bool flagStarMagnitudeLimit READ getFlagStarMagnitudeLimit WRITE setFlagStarMagnitudeLimit NOTIFY flagStarMagnitudeLimitChanged)
    Q_PROPERTY(bool flagNebulaMagnitudeLimit READ getFlagNebulaMagnitudeLimit WRITE setFlagNebulaMagnitudeLimit NOTIFY flagNebulaMagnitudeLimitChanged)
    Q_PROPERTY(bool flagPlanetMagnitudeLimit READ getFlagPlanetMagnitudeLimit WRITE setFlagPlanetMagnitudeLimit NOTIFY flagPlanetMagnitudeLimitChanged)

    Q_PROPERTY(double customStarMagLimit READ getCustomStarMagnitudeLimit WRITE setCustomStarMagnitudeLimit NOTIFY customStarMagLimitChanged)
    Q_PROPERTY(double customNebulaMagLimit READ getCustomNebulaMagnitudeLimit WRITE setCustomNebulaMagnitudeLimit NOTIFY customNebulaMagLimitChanged)
    Q_PROPERTY(double customPlanetMagLimit READ getCustomPlanetMagnitudeLimit WRITE setCustomPlanetMagnitudeLimit NOTIFY customPlanetMagLimitChanged)

    Q_PROPERTY(bool flagLuminanceAdaptation READ getFlagLuminanceAdaptation WRITE setFlagLuminanceAdaptation NOTIFY flagLuminanceAdaptationChanged)

    Q_PROPERTY(double extinctionCoefficient READ getExtinctionCoefficient WRITE setExtinctionCoefficient NOTIFY extinctionCoefficientChanged)
    Q_PROPERTY(double atmosphereTemperature READ getAtmosphereTemperature WRITE setAtmosphereTemperature NOTIFY atmosphereTemperatureChanged)
    Q_PROPERTY(double atmospherePressure READ getAtmospherePressure WRITE setAtmospherePressure NOTIFY atmospherePressureChanged)

public:

    StelSkyDrawer(StelCore* core);
    ~StelSkyDrawer();

    void init();

    void update(double deltaTime);

    void preDrawPointSource(StelPainter* p);

    void postDrawPointSource(StelPainter* sPainter);

    bool drawPointSource(StelPainter* sPainter, const Vec3f& v, const RCMag &rcMag, unsigned int bV, bool checkInScreen=false, float twinkleFactor=1.0f)
    {
        return drawPointSource(sPainter, v, rcMag, colorTable[bV], checkInScreen, twinkleFactor);
    }

    bool drawPointSource(StelPainter* sPainter, const Vec3f& v, const RCMag &rcMag, const Vec3f& bcolor, bool checkInScreen=false, float twinkleFactor=1.0f);

    void drawSunCorona(StelPainter* painter, const Vec3f& v, float radius, const Vec3f& color, const float alpha);

    void postDrawSky3dModel(StelPainter* p, const Vec3f& v, float illuminatedArea, float mag, const Vec3f& color = Vec3f(1.f,1.f,1.f));

    bool computeRCMag(float mag, RCMag*) const;

    void reportLuminanceInFov(float lum, bool fastAdaptation=false);

    void preDraw();

    static float surfaceBrightnessToLuminance(float sb);
    static float luminanceToSurfacebrightness(float lum);

    static inline float indexToBV(unsigned char bV)
    {
        return (float)bV*(4.f/127.f)-0.5f;
    }

    static inline const Vec3f& indexToColor(unsigned char bV)
    {
        return colorTable[bV];
    }

public slots:
    void setRelativeStarScale(double b=1.0) {if(b!=starRelativeScale){ starRelativeScale=b; emit relativeStarScaleChanged(b);}}
    double getRelativeStarScale() const {return starRelativeScale;}

    void setAbsoluteStarScale(double b=1.0) {if(b!=starAbsoluteScaleF){ starAbsoluteScaleF=b; emit absoluteStarScaleChanged(b);}}
    double getAbsoluteStarScale() const {return starAbsoluteScaleF;}

    void setTwinkleAmount(double b) {if(b!=twinkleAmount){ twinkleAmount=b; emit twinkleAmountChanged(b);}}
    double getTwinkleAmount() const {return twinkleAmount;}

    void setFlagTwinkle(bool b) {if(b!=flagStarTwinkle){ flagStarTwinkle=b; emit flagTwinkleChanged(b);}}
    bool getFlagTwinkle() const {return flagStarTwinkle;}

    void setFlagForcedTwinkle(bool b) {if(b!=flagForcedTwinkle){ flagForcedTwinkle=b;}}
    bool getFlagForcedTwinkle() const {return flagForcedTwinkle;}

    void setBortleScaleIndex(int index);
    int getBortleScaleIndex() const {return bortleScaleIndex;}
    float getNELMFromBortleScale() const;

    float getLimitMagnitude() const {return limitMagnitude;}

    // FIXME: Exposed to scripts - make sure it synchs with the GUI. --BM
    void setFlagStarMagnitudeLimit(bool b) {if(b!=flagStarMagnitudeLimit){ flagStarMagnitudeLimit = b; emit flagStarMagnitudeLimitChanged(b);}}
    bool getFlagStarMagnitudeLimit() const {return flagStarMagnitudeLimit;}
    // FIXME: Exposed to scripts - make sure it synchs with the GUI. --BM
    void setFlagNebulaMagnitudeLimit(bool b) {if(b!=flagNebulaMagnitudeLimit){ flagNebulaMagnitudeLimit = b; emit flagNebulaMagnitudeLimitChanged(b);}}
    bool getFlagNebulaMagnitudeLimit() const {return flagNebulaMagnitudeLimit;}
    // FIXME: Exposed to scripts - make sure it synchs with the GUI. --BM  --- GZ: this was copy/paste. Track down BM's changes!!!
    void setFlagPlanetMagnitudeLimit(bool b) {if(b!=flagPlanetMagnitudeLimit){ flagPlanetMagnitudeLimit = b; emit flagPlanetMagnitudeLimitChanged(b);}}
    bool getFlagPlanetMagnitudeLimit() const {return flagPlanetMagnitudeLimit;}

    double getCustomStarMagnitudeLimit() const {return customStarMagLimit;}
    void setCustomStarMagnitudeLimit(double limit) {if(limit!=customStarMagLimit){ customStarMagLimit=limit; emit customStarMagLimitChanged(limit);}}
    double getCustomNebulaMagnitudeLimit() const {return customNebulaMagLimit;}
    void setCustomNebulaMagnitudeLimit(double limit) {if(limit!=customNebulaMagLimit){ customNebulaMagLimit=limit; emit customNebulaMagLimitChanged(limit);}}
    double getCustomPlanetMagnitudeLimit() const {return customPlanetMagLimit;}
    void setCustomPlanetMagnitudeLimit(double limit) {if(limit!=customPlanetMagLimit){ customPlanetMagLimit=limit; emit customPlanetMagLimitChanged(limit);}}

    float getLimitLuminance() const {return limitLuminance;}

    void setFlagLuminanceAdaptation(bool b) {if(b!=flagLuminanceAdaptation){ flagLuminanceAdaptation=b; emit flagLuminanceAdaptationChanged(b);}}
    bool getFlagLuminanceAdaptation() const {return flagLuminanceAdaptation;}

    void setFlagHasAtmosphere(bool b) {flagHasAtmosphere=b;}
    bool getFlagHasAtmosphere() const {return flagHasAtmosphere;}

    void setExtinctionCoefficient(double extCoeff) {if(extCoeff!=extinction.getExtinctionCoefficient()){ extinction.setExtinctionCoefficient(extCoeff); emit extinctionCoefficientChanged(extinction.getExtinctionCoefficient());}}
    double getExtinctionCoefficient() const {return extinction.getExtinctionCoefficient();}
    void setAtmosphereTemperature(double celsius) {if(celsius!=refraction.getTemperature()){refraction.setTemperature(celsius); emit atmosphereTemperatureChanged(refraction.getTemperature());}}
    double getAtmosphereTemperature() const {return refraction.getTemperature();}
    void setAtmospherePressure(double mbar) {if(mbar!=refraction.getPressure()){ refraction.setPressure(mbar); emit atmospherePressureChanged(refraction.getPressure());}}
    double getAtmospherePressure() const {return refraction.getPressure();}

    const Extinction& getExtinction() const {return extinction;}
    const Refraction& getRefraction() const {return refraction;}

    float getBig3dModelHaloRadius() const {return big3dModelHaloRadius;}
    void setBig3dModelHaloRadius(float r) {big3dModelHaloRadius=r;}
signals:
    void relativeStarScaleChanged(double b);
    void absoluteStarScaleChanged(double b);
    void twinkleAmountChanged(double b);
    void flagTwinkleChanged(bool b);
    void bortleScaleIndexChanged(int index);

    void flagStarMagnitudeLimitChanged(bool b);
    void flagNebulaMagnitudeLimitChanged(bool b);
    void flagPlanetMagnitudeLimitChanged(bool b);

    void customStarMagLimitChanged(double limit);
    void customNebulaMagLimitChanged(double limit);
    void customPlanetMagLimitChanged(double limit);

    void flagLuminanceAdaptationChanged(bool b);

    void extinctionCoefficientChanged(double coeff);
    void atmosphereTemperatureChanged(double celsius);
    void atmospherePressureChanged(double mbar);
    
private:
    // Debug
    float reverseComputeRCMag(float rmag) const;

    float computeLimitMagnitude() const;

    float computeLimitLuminance() const;

    float getMaxAdaptFov(void) const {return maxAdaptFov;}
    void setMaxAdaptFov(float fov) {maxAdaptFov = (fov < 60.f) ? 60.f : fov;}

    float getMinAdaptFov(void) const {return minAdaptFov;}
    void setMinAdaptFov(float fov) {minAdaptFov = (fov > 60.f) ? 60.f : fov;}

    void setInputScale(float in) {inScale = in;}
    float getInputScale() const {return inScale;}

    inline float pointSourceMagToLuminance(float mag) const {return std::exp(pointSourceMagToLnLuminance(mag));}

    float pointSourceLuminanceToMag(float lum);

    float pointSourceMagToLnLuminance(float mag) const;

    float findWorldLumForMag(float mag, float targetRadius);

    StelCore* core;
    StelToneReproducer* eye;

    Extinction extinction;
    Refraction refraction;

    float maxAdaptFov, minAdaptFov, lnfovFactor;
    bool flagStarTwinkle;
    bool flagForcedTwinkle;
    double twinkleAmount;

    bool flagHasAtmosphere;

    bool flagStarMagnitudeLimit;
    bool flagNebulaMagnitudeLimit;
    bool flagPlanetMagnitudeLimit;

    double starRelativeScale;
    double starAbsoluteScaleF;

    float starLinearScale;  // optimization variable

    float limitMagnitude;

    float limitLuminance;

    double customStarMagLimit;
    //  GZ To explain: we have 3 limits for stars, nebulae, planets. It's easier to maintain the pretty similar code in 1 place.
    double customNebulaMagLimit;
    double customPlanetMagLimit;

    StelTextureSP texHalo;

    void initColorTableFromConfigFile(class QSettings* conf);

    static Vec3f colorTable[128];

    int bortleScaleIndex;

    float inScale;

    // Variables used for GL optimization when displaying point sources
    struct StarVertex {
        Vec2f pos;
        unsigned char color[4];
    };
    
    StarVertex* vertexArray;

    unsigned char* textureCoordArray;
    
    class QOpenGLShaderProgram* starShaderProgram;
    struct StarShaderVars {
        int projectionMatrix;
        int texCoord;
        int pos;
        int color;
        int texture;
    };
    StarShaderVars starShaderVars;
    
    unsigned int nbPointSources;
    unsigned int maxPointSources;

    float maxLum;
    float oldLum;

    StelTextureSP texBigHalo;
    StelTextureSP texSunHalo;
    StelTextureSP texSunCorona;

    bool flagLuminanceAdaptation;

    float big3dModelHaloRadius;
};

#endif // _STELSKYDRAWER_HPP_