/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

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 * file, You can obtain one at http://mozilla.org/MPL/2.0/.

 *

 * This file incorporates work covered by the following license notice:

 *

 *   Licensed to the Apache Software Foundation (ASF) under one or more

 *   contributor license agreements. See the NOTICE file distributed

 *   with this work for additional information regarding copyright

 *   ownership. The ASF licenses this file to you under the Apache

 *   License, Version 2.0 (the "License"); you may not use this file

 *   except in compliance with the License. You may obtain a copy of

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#include <drawinglayer/attribute/sdrlightingattribute3d.hxx>

#include <basegfx/color/bcolor.hxx>

#include <basegfx/vector/b3dvector.hxx>

#include <drawinglayer/attribute/sdrlightattribute3d.hxx>

namespace drawinglayer::attribute

{

        class ImpSdrLightingAttribute

        {

        public:

            // 3D light attribute definitions

            basegfx::BColor                         maAmbientLight;

            std::vector< Sdr3DLightAttribute >    maLightVector;

            ImpSdrLightingAttribute(

                const basegfx::BColor& rAmbientLight,

                std::vector< Sdr3DLightAttribute >&& rLightVector)

            :   maAmbientLight(rAmbientLight),

                maLightVector(std::move(rLightVector))

            {

            }

            ImpSdrLightingAttribute()

            {

            }

            // data read access

            const basegfx::BColor& getAmbientLight() const { return maAmbientLight; }

            const std::vector< Sdr3DLightAttribute >& getLightVector() const { return maLightVector; }

            bool operator==(const ImpSdrLightingAttribute& rCandidate) const

            {

                return (getAmbientLight() == rCandidate.getAmbientLight()

                    && getLightVector() == rCandidate.getLightVector());

            }

        };

        namespace

        {

            SdrLightingAttribute::ImplType& theGlobalDefault()

            {

                static SdrLightingAttribute::ImplType SINGLETON;

                return SINGLETON;

            }

        }

        SdrLightingAttribute::SdrLightingAttribute(

            const basegfx::BColor& rAmbientLight,

            std::vector< Sdr3DLightAttribute >&& rLightVector)

        :   mpSdrLightingAttribute(ImpSdrLightingAttribute(

                rAmbientLight, std::move(rLightVector)))

        {

        }

        SdrLightingAttribute::SdrLightingAttribute()

        :   mpSdrLightingAttribute(theGlobalDefault())

        {

        }

        SdrLightingAttribute::SdrLightingAttribute(const SdrLightingAttribute&) = default;

        SdrLightingAttribute::SdrLightingAttribute(SdrLightingAttribute&&) = default;

        SdrLightingAttribute::~SdrLightingAttribute() = default;

        bool SdrLightingAttribute::isDefault() const

        {

            return mpSdrLightingAttribute.same_object(theGlobalDefault());

        }

        SdrLightingAttribute& SdrLightingAttribute::operator=(const SdrLightingAttribute&) = default;

        SdrLightingAttribute& SdrLightingAttribute::operator=(SdrLightingAttribute&&) = default;

        bool SdrLightingAttribute::operator==(const SdrLightingAttribute& rCandidate) const

        {

            // tdf#87509 default attr is always != non-default attr, even with same values

            if(rCandidate.isDefault() != isDefault())

                return false;

            return rCandidate.mpSdrLightingAttribute == mpSdrLightingAttribute;

        }

        const std::vector< Sdr3DLightAttribute >& SdrLightingAttribute::getLightVector() const

        {

            return mpSdrLightingAttribute->getLightVector();

        }

        const basegfx::BColor& SdrLightingAttribute::getAmbientLightColor() const

        {

            return mpSdrLightingAttribute->maAmbientLight;

        }

        // color model solver

        basegfx::BColor SdrLightingAttribute::solveColorModel(

            const basegfx::B3DVector& rNormalInEyeCoordinates,

            const basegfx::BColor& rColor, const basegfx::BColor& rSpecular,

            const basegfx::BColor& rEmission, sal_uInt16 nSpecularIntensity) const

        {

            // initialize with emissive color

            basegfx::BColor aRetval(rEmission);

            // take care of global ambient light

            aRetval += mpSdrLightingAttribute->getAmbientLight() * rColor;

            const std::vector<Sdr3DLightAttribute>& rLightVector = mpSdrLightingAttribute->getLightVector();

            // prepare light access. Is there a light?

            const sal_uInt32 nLightCount(rLightVector.size());

            if(nLightCount && !rNormalInEyeCoordinates.equalZero())

            {

                // prepare normal

                basegfx::B3DVector aEyeNormal(rNormalInEyeCoordinates);

                aEyeNormal.normalize();

                for(sal_uInt32 a(0); a < nLightCount; a++)

                {

                    const Sdr3DLightAttribute& rLight(rLightVector[a]);

                    const double fCosFac(rLight.getDirection().scalar(aEyeNormal));

                    if(fCosFac > 0.0)

                    {

                        aRetval += (rLight.getColor() * rColor) * fCosFac;

                        if(rLight.getSpecular())

                        {

                            // expand by (0.0, 0.0, 1.0) in Z

                            basegfx::B3DVector aSpecularNormal(rLight.getDirection().getX(), rLight.getDirection().getY(), rLight.getDirection().getZ() + 1.0);

                            aSpecularNormal.normalize();

                            double fCosFac2(aSpecularNormal.scalar(aEyeNormal));

                            if(fCosFac2 > 0.0)

                            {

                                fCosFac2 = pow(fCosFac2, static_cast<double>(nSpecularIntensity));

                                aRetval += rSpecular * fCosFac2;

                            }

                        }

                    }

                }

            }

            // clamp to color space before usage

            aRetval.clamp();

            return aRetval;

        }

} // end of namespace

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