Meteor.hpp

/*
 * Stellarium
 * This file Copyright (C) 2004 Robert Spearman
 * 
 * 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 _METEOR_HPP_
#define _METEOR_HPP_

#include "renderer/StelVertexAttribute.hpp"
#include "renderer/StelVertexBuffer.hpp"
#include "StelProjector.hpp"
#include "VecMath.hpp"
class StelCore;

// all in km - altitudes make up meteor range
#define EARTH_RADIUS 6369.f
#define HIGH_ALTITUDE 115.f
#define LOW_ALTITUDE 70.f
#define VISIBLE_RADIUS 457.8f

class Meteor
{
public:
    Meteor(const StelCore*, double v);
    virtual ~Meteor();
    
    bool update(double deltaTime);
    
    void draw(const StelCore* core, StelProjectorP projector, class StelRenderer* renderer);
    
    bool isAlive(void);
    
private:
    struct Vertex
    {
        Vec3f position;
        Vec4f color;
        Vertex(const Vec3d& pos, const Vec4f& color) 
            : position(Vec3f(pos[0], pos[1], pos[2])), color(color) {}
        VERTEX_ATTRIBUTES(Vec3f Position, Vec4f Color);
    };

    StelVertexBuffer<Vertex>* vertexBuffer;

    Mat4d mmat; // tranformation matrix to align radiant with earth direction of travel
    Vec3d obs;  // observer position in meteor coord. system
    Vec3d position;  // equatorial coordinate position
    Vec3d posInternal;  // middle of train
    Vec3d posTrain;  // end of train
    bool train;      // point or train visible?
    double startH;  // start height above center of earth
    double endH;    // end height
    double velocity; // km/s
    bool alive;      // is it still visible?
    float mag;     // Apparent magnitude at head, 0-1
    float maxMag;  // 0-1
    float absMag;  // absolute magnitude
    float visMag;  // visual magnitude at observer
    double xydistance; // distance in XY plane (orthogonal to meteor path) from observer to meteor
    double initDist;  // initial distance from observer
    double minDist;  // nearest point to observer along path
    double distMultiplier;  // scale magnitude due to changes in distance 
};


#endif // _METEOR_HPP_