/* the solar system 3D        */
/* coded by Ikeuchi Mitsuru   */
/* ver 0.0.1   2003.08.24     */
/* ver 0.0.2   2003.08.27  change to realistic r and v */

import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class solarSystem3D extends Applet
  implements MouseListener, MouseMotionListener,
    ItemListener, AdjustmentListener, Runnable {

/*-------------------------------------- define gloval -----*/

  Choice cvw;
  Scrollbar scs;
  Thread th = null;

  Dimension dim;
  Image imgOff;
  Graphics gOff;

  int sleepTime = 30;

  double scale = 1.0;
  int dispMode = 0;

  int dgX, dgY, dgXb,dgYb;
  double cx = 0.0;
  double cy = 0.0;
  double cz = 0.0;
  double theta = 15.0*3.14/180.0;
  double fai = 108.0*3.14/180.0;
  double dtheta = 0.0*3.14/180.0;
  double pai = 3.1415926536;

  double t = 0.0;              /* time (s)               */
  double dt = 3600.0;          /* time division (s)      */

  double solarSys[][] = {
  /*                mass(kg)  radious(m) orbitR(m) v_tan(m/s) color */
  /* 0 Sun     */ { 1.9890e30, 6.960e8,       0.0,      0.0,  0.01 },
  /* 1 Mercury */ { 3.3022e23, 2.440e6,  5.790e10,  4.790e4,  0.60 },
  /* 2 Venus   */ { 4.8690e24, 6.052e6,  1.082e11,  3.505e4,  0.85 },
  /* 3 Earth   */ { 5.9742e24, 6.378e6,  1.496e11,  2.980e4,  0.33 },
  /* 4 Mars    */ { 6.4191e23, 3.397e6,  2.280e11,  2.414e4,  0.08 },
  /* 5 Jupiter */ { 1.8988e27, 7.149e7,  7.784e11,  1.306e4,  0.45 },
  /* 6 Saturn  */ { 5.6841e26, 6.027e7, 1.4246e12,  9.650e3,  0.50 },
  /* 7 Uranus  */ { 8.6967e25, 2.556e7, 2.8669e12,  6.800e3,  0.55 },
  /* 8 Neptune */ { 1.0285e26, 2.476e7, 4.4860e12,  5.430e3,  0.60 },
  /* 9 Pluto   */ { 1.4000e22, 1.137e6, 5.8897e12,  4.740e3,  0.75 }
  };

  int Nmt = 10; 
  int NN = Nmt + 1;

  double AU = 1.49597870e11;

  /*  data from Web Version of MICA                        */ 
  /*  http://aa.usno.navy.mil/data/docs/WebMICA_2.html     */
  /*  2003 Jan 01 00:00:00.0 - 02:00:00.0                  */

  double posXYZ[][][] = { 
    { /* 0 Sun */
      { +0.001358537, -0.004387529, -0.001897513 },    
      { +0.001358834, -0.004387372, -0.001897454 },   
      { +0.001359131, -0.004387214, -0.001897394 } },
    { /* 1 Mercury */
      { +0.229184455, +0.198328442, +0.082759575 },
      { +0.228137761, +0.199079593, +0.083269366 },
      { +0.227087386, +0.199827443, +0.083777775 } },
    { /* 2 Venus */
      { -0.524625643, +0.428639950, +0.226207669 },
      { -0.525201284, +0.428059124, +0.225982795 },
      { -0.525776197, +0.427477699, +0.225757605 } },
    { /* 3 Earth */
      { -0.171170878, +0.883816752, +0.383177939 },
      { -0.171888243, +0.883698845, +0.383126842 },
      { -0.172605514, +0.883580456, +0.383075536 } },
    { /* 4 Mars */
      { -1.502331750, -0.557843298, -0.215113746 },
      { -1.502095722, -0.558288672, -0.215324408 },
      { -1.501859512, -0.558733978, -0.215535045 } },
    { /* 5 Jupiter */
      { -3.440225378, +3.671532995, +1.657499617 },
      { -3.440468380, +3.671356832, +1.657430024 },
      { -3.440711371, +3.671180657, +1.657360424 } },
    { /* 6 Saturn */
      { +0.617032002, +8.336344971, +3.416667095 },
      { +0.616787728, +8.336355304, +3.416681879 },
      { +0.616543453, +8.336365632, +3.416696661 } },
    { /* 7 Uranus */
      { +17.021312941, -9.560537477, -4.428021449 },
      { +17.021397975, -9.560416379, -4.427969614 },
      { +17.021483008, -9.560295281, -4.427917778 } },
    { /* 8 Neptune */
      { +19.520965719, -21.016674783, -9.088236086 },
      { +19.521064398, -21.016594627, -9.088205735 },
      { +19.521163077, -21.016514471, -9.088175383 } },
    { /* 9 Pluto */
      { -6.503495729, -29.044102940, -7.104381294 },
      { -6.503365358, -29.044136477, -7.104431040 },
      { -6.503234987, -29.044170013, -7.104480786 } }
  };


  int kind[] = new int[NN];
  double mass[] = new double[NN];
  double radious[] = new double[NN];
  double xx[] = new double[NN];   /* i-th x-position */
  double yy[] = new double[NN];   /* i-th y-position */
  double zz[] = new double[NN];   /* i-th z-position */
  double vx[] = new double[NN];   /* i-th x-velocity */
  double vy[] = new double[NN];   /* i-th y-velocity */
  double vz[] = new double[NN];   /* i-th z-velocity */
  double ffx[] = new double[NN];  /* i-th x-force    */
  double ffy[] = new double[NN];  /* i-th y-force    */
  double ffz[] = new double[NN];  /* i-th z-force    */
  double fbx[] = new double[NN];  /* i-th x-force before dt */
  double fby[] = new double[NN];  /* i-th y-force before dt */
  double fbz[] = new double[NN];  /* i-th z-force before dt */


  int srtz[][] = new int[2][NN];   /* z-sort work space */

  double px[] = new double[NN]; 
  double py[] = new double[NN]; 
  double pz[] = new double[NN]; 

  double pnt[][] = {
    { 0.0,    0.0,    0.0 },
    { 1.0e11, 0.0,    0.0 },
    { 0.0,    1.0e11, 0.0 },
    { 0.0,    0.0, 1.0e11 }
  };

  double ppnt[][] = new double[4][3];


/*----------------------------- applet control functions -----*/

  public void init() {
    resize(630,360);
    setBackground(Color.white);

    dim = getSize();
    imgOff = createImage(dim.width,dim.height);
    gOff = imgOff.getGraphics();

    scs= new Scrollbar(Scrollbar.HORIZONTAL,100,10,10,510);
    add(new Label("scale=")); add(scs);
    scs.addAdjustmentListener(this);

    addMouseListener(this);  
    addMouseMotionListener(this);

    cvw = new Choice();
    cvw.addItem("axis");  cvw.addItem("no axis");
    add(new Label("view=")); add(cvw);
    cvw.addItemListener(this); 

    setInitialPosition();
    offPaint();
    repaint();
  }

  public void start() {
    if (th == null) {
      th = new Thread(this);
      th.start();
    }
  }

  public void stop() {
    if (th != null) {
      th.stop();
      th = null;
    }
  }

  public void itemStateChanged(ItemEvent ev){
    if (ev.getSource() == cvw){
      dispMode = cvw.getSelectedIndex();
      offPaint();
      repaint(); 
    }
  }

  public void adjustmentValueChanged(AdjustmentEvent ev){
    if (ev.getSource() == scs) { 
      scale = 0.01*(double)(scs.getValue());
      repaint();
    }
  }

  public void mousePressed(MouseEvent ev){ }
  public void mouseReleased(MouseEvent ev){
    dgXb = 0; dgYb = 0;
    dgX = 0; dgY = 0;
  }
  public void mouseClicked(MouseEvent ev){ }
  public void mouseEntered(MouseEvent ev){ } 
  public void mouseExited (MouseEvent ev){ }

  public void mouseMoved  (MouseEvent ev){ }

  public void mouseDragged(MouseEvent ev){
    dgXb = dgX; dgYb = dgY;
    dgX=ev.getX();
    dgY=ev.getY();
    if (dgXb==0 && dgYb==0) {
      dgXb = dgX; dgYb = dgY;
    }
    theta -= 0.5*3.14/180.0*(dgX-dgXb);
    fai += 0.5*3.14/180.0*(dgY-dgYb);
  }

  public void run() {
    while (th != null) {
      try {
        calcposition();
        offPaint();
        repaint();
        Thread.sleep(sleepTime);
      } catch (InterruptedException e) { }
    }
  }

  public void update(Graphics g) {
    paint(g);
  }

  public void paint(Graphics g) {
    g.drawImage(imgOff,0,0,this);
  }


/* ----------------------------- offPaint -------------------- */

  void offPaint() {
    int i,j,k;
    int ix,iy,ir,ilx,ily,ilx2,ily2;
    double mag;

    gOff.setColor(Color.black);
    gOff.fillRect(0,0,dim.width,dim.height);

    rotate(theta,fai);
    zSort();


    if (dispMode==0) {

      for (i=0; i<Nmt; i++) {
        j = srtz[0][i];
        ix = (int)(scale*px[j]/1.0e9+0.499)+200;
        iy = -(int)(scale*py[j]/1.0e9+0.499)+180;
        mag = (pz[j]+1.0e12)/1.0e12;
        if (mag>2.0) {
          mag = 2.0;
        } else if (mag<0.1) {
          mag = 0.1;
        }
        ir = (int)(scale*radious[j]/1.0e6*mag+0.499)+3;
        if (j==0) {
          gOff.setColor(Color.gray);
          for (k=1; k<4; k++) {
            ilx = (int)(scale*ppnt[0][0]/1.0e9+0.499)+200;
            ily = -(int)(scale*ppnt[0][1]/1.0e9+0.499)+180;
            ilx2 = (int)(scale*ppnt[k][0]/1.0e9+0.499)+200;
            ily2 = -(int)(scale*ppnt[k][1]/1.0e9+0.499)+180;
            gOff.drawLine(ilx,ily,ilx2,ily2);

            if (k==1) {
              gOff.drawString("x",ilx2,ily2);
            } else if (k==2) {
              gOff.drawString("y",ilx2,ily2);
            } else if (k==3) {
              gOff.drawString("z",ilx2,ily2);
            } 

          }
        }
        gOff.setColor(Color.getHSBColor( (float)(solarSys[j][4]),0.95f,0.95f));
        gOff.fillOval(ix-ir/2,iy-ir/2, ir, ir);
      }

    } else if (dispMode==1) {

      for (i=0; i<Nmt; i++) {
        j = srtz[0][i];
        ix = (int)(scale*px[j]/1.0e9+0.499)+200;
        iy = -(int)(scale*py[j]/1.0e9+0.499)+180;
        mag = (pz[j]+1.0e12)/1.0e12;
        if (mag>2.0) {
          mag = 2.0;
        } else if (mag<0.1) {
          mag = 0.1;
        }
        ir = (int)(scale*radious[j]/1.0e6*mag+0.499)+3;
        gOff.setColor(Color.getHSBColor( (float)(solarSys[j][4]),0.95f,0.95f));
        gOff.fillOval(ix-ir/2,iy-ir/2, ir, ir);
      }

    }


    gOff.setColor(Color.yellow);
    gOff.drawString("scale="+(int)(scale*100.0+0.499)+"%",500,20);
    gOff.drawString("from 2003.01.01",500,40);
    gOff.drawString("t="+(int)(t/3600.0/24.0+0.499)+"(day)",500,60);

    gOff.setColor(Color.getHSBColor((float)(solarSys[0][4]),0.95f,0.95f));
    gOff.drawString("Sun",500,200);
    gOff.setColor(Color.getHSBColor((float)(solarSys[1][4]),0.95f,0.95f));
    gOff.drawString("Mercury",500,220);
    gOff.setColor(Color.getHSBColor((float)(solarSys[2][4]),0.95f,0.95f));
    gOff.drawString("Venus",500,240);
    gOff.setColor(Color.getHSBColor((float)(solarSys[3][4]),0.95f,0.95f));
    gOff.drawString("Earth",500,260);
    gOff.setColor(Color.getHSBColor((float)(solarSys[4][4]),0.95f,0.95f));
    gOff.drawString("Mars",500,280);
    gOff.setColor(Color.getHSBColor((float)(solarSys[5][4]),0.95f,0.95f));
    gOff.drawString("Jupiter",500,300);

    gOff.setColor(Color.yellow);
    gOff.drawString("Earth-Mars",500,90);
    gOff.drawString("d="+(int)(distance(3,4)/1.0e3+0.499)+"(km)",500,110);

/*
    gOff.setColor(Color.yellow);
    gOff.drawString("theta="+(int)(theta*180.0/3.1416+0.49)+"",500,90);
    gOff.drawString("fai="+(int)(fai*180.0/3.1416+0.49)+"",500,110);
*/
  }

  double distance(int i, int j) {
    double x,y,z;

    x = xx[i] - xx[j];
    y = yy[i] - yy[j];
    z = zz[i] - zz[j];
    return(Math.sqrt(x*x+y*y+z*z));

  }


/*-------------------------------------  sort z  ----------*/

  void zSort() {
    int i,j,w;

    for (i=0; i<Nmt; i++) {
      srtz[0][i] = i;
      srtz[1][i] = (int)(pz[i]/1.0e9+0.5);
    } 
    for (i=0; i<Nmt; i++) {
      for (j=0; j<Nmt-1; j++) {
        if (srtz[1][j]>srtz[1][j+1]) {
          w = srtz[0][j]; srtz[0][j]=srtz[0][j+1]; srtz[0][j+1]=w;
          w = srtz[1][j]; srtz[1][j]=srtz[1][j+1]; srtz[1][j+1]=w;
        }
      }
    }  
  
  }

/*-------------------------------------  rotate  ----------*/

  void rotate(double th,double fi) {
    int i;
    double cosTh,sinTh,cosFi,sinFi;

    cosTh = Math.cos(th); sinTh = Math.sin(th);
    cosFi = Math.cos(fi); sinFi = Math.sin(fi);
    for (i=0; i<Nmt; i++) {
      py[i] = cosFi*(yy[i]-cy)+sinFi*(zz[i]-cz) + cy; 
      pz[i] = -sinFi*(yy[i]-cy)+cosFi*(zz[i]-cz) + cz;
    } 
    for (i=0; i<4; i++) {
      ppnt[i][1] = cosFi*(pnt[i][1]-cy)+sinFi*(pnt[i][2]-cz) + cy; 
      ppnt[i][2] = -sinFi*(pnt[i][1]-cy)+cosFi*(pnt[i][2]-cz) + cz;
    } 

    for (i=0; i<Nmt; i++) {
      px[i] = cosTh*(xx[i]-cx)+sinTh*(pz[i]-cz) + cx; 
      pz[i] = -sinTh*(xx[i]-cx)+cosTh*(pz[i]-cz) + cz;
    } 
    for (i=0; i<4; i++) {
      ppnt[i][0] = cosTh*(pnt[i][0]-cx)+sinTh*(ppnt[i][2]-cz) + cx; 
      ppnt[i][2] = -sinTh*(pnt[i][0]-cx)+cosTh*(ppnt[i][2]-cz) + cz;
    } 

  }


/*-------------------------  set initial condition   ---------*/

  void setInitialPosition(){
    int i; 

    for (i=0; i<Nmt; i++) {
      mass[i] = solarSys[i][0];
      radious[i] = solarSys[i][1];
      xx[i] = posXYZ[i][1][0]*AU;
      yy[i] = posXYZ[i][1][1]*AU;
      zz[i] = posXYZ[i][1][2]*AU;
      vx[i] = (posXYZ[i][2][0]*AU-posXYZ[i][0][0]*AU)/7200.0;
      vy[i] = (posXYZ[i][2][1]*AU-posXYZ[i][0][1]*AU)/7200.0;
      vz[i] = (posXYZ[i][2][2]*AU-posXYZ[i][0][2]*AU)/7200.0;
      ffx[i] = 0.0;
      ffy[i] = 0.0;
      ffz[i] = 0.0;
      fbx[i] = 0.0;
      fby[i] = 0.0;
      fbz[i] = 0.0;
    }
    radious[0] = solarSys[0][1]/50.0;

  }


/*-------------------------------  molecules motion   ---------*/

  void calcposition(){
    int i;

    for (i=0; i<24; i++) {

      timeEvolution();

    }
  }


  void timeEvolution(){
    int i; 

    t = t + dt;

    for (i=0; i<Nmt; i++) {
      xx[i] += vx[i]*dt+0.5*dt*dt*ffx[i]/mass[i];
      yy[i] += vy[i]*dt+0.5*dt*dt*ffy[i]/mass[i];
      zz[i] += vz[i]*dt+0.5*dt*dt*ffz[i]/mass[i];
      fbx[i] = ffx[i];
      fby[i] = ffy[i];
      fbz[i] = ffz[i];
    }
    forceCalc();
    for (i=0; i<Nmt; i++) {
      vx[i] += 0.5*dt*(ffx[i]+fbx[i])/mass[i];
      vy[i] += 0.5*dt*(ffy[i]+fby[i])/mass[i];
      vz[i] += 0.5*dt*(ffz[i]+fbz[i])/mass[i];
    }

  }

  void forceCalc() {
    int i,j;
    double rij,f,fxij,fyij,fzij;

    for(i=0;i<Nmt;i++) {
      ffx[i] = 0.0;
      ffy[i] = 0.0;
      ffz[i] = 0.0;
    }

    for(i=0;i<Nmt;i++) {
      for(j=i+1;j<Nmt;j++) {
        rij = Math.sqrt((xx[i]-xx[j])*(xx[i]-xx[j])+(yy[i]-yy[j])*(yy[i]-yy[j])+(zz[i]-zz[j])*(zz[i]-zz[j]));
        f = force(rij,i,j);
        fxij = f*(xx[i]-xx[j])/rij;
        fyij = f*(yy[i]-yy[j])/rij;
        fzij = f*(zz[i]-zz[j])/rij;

        ffx[i] += fxij;
        ffy[i] += fyij;
        ffz[i] += fzij;

        ffx[j] += -fxij;
        ffy[j] += -fyij;
        ffz[j] += -fzij;
      }
    }
  }


  double force(double rij, int ii, int jj) {
    double gg;

    gg = 6.672e-11; 

    return ( -gg*mass[ii]*mass[jj]/(rij*rij) );
  }


/*----- end of molecules motion -----*/

}  

/*----- end of applet -----*/