earth.h


// Copyright (c) 2011-2012, Daniel Müller <dm@g4t3.de>
// Computer Graphics Systems Group at the Hasso-Plattner-Institute, Germany
// All rights reserved.
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#pragma once

namespace osgCloudyDay
{
        class  Earth
        {
        public:

                static const double atmosphericRefraction(const double altitude);

                static const double viewDistanceWithinAtmosphere(
                        const double y /* height component of the view direction on ground into the sky */
                ,   const bool refractionCorrected = false);
                
                static const double meanRadius();
                static double atmosphereThickness(); // if its density were uniform...
                static const double atmosphereThicknessNonUniform();

                static const double apparentMagnitudeLimit();
        };
}