/**
 * dlentry.java - entry in a drawing list
 * Copyright (c) 1997 Will Ware, all rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    or its derived works must display the following acknowledgement:
 *      This product includes software developed by Will Ware.
 *
 * This software is provided "as is" and any express or implied warranties,
 * including, but not limited to, the implied warranties of merchantability
 * or fitness for any particular purpose are disclaimed. In no event shall
 * Will Ware be liable for any direct, indirect, incidental, special,
 * exemplary, or consequential damages (including, but not limited to,
 * procurement of substitute goods or services; loss of use, data, or
 * profits; or business interruption) however caused and on any theory of
 * liability, whether in contract, strict liability, or tort (including
 * negligence or otherwise) arising in any way out of the use of this
 * software, even if advised of the possibility of such damage.
 */

import java.awt.*;
import java.util.Vector;
import atom;

public class dl_bond extends dlentry
{
  public static final String rcsid =
  "$Id: dl_bond.java,v 1.2 1997/09/12 13:23:02 wware Exp $";
  private double x1[], r1;  // screen coordinates for first atom
  private double x2[], r2;
  private atom atm1, atm2;
  // gap between lines in double and triple bonds, in angstroms
  private static final double gap = 0.2;
  public dl_bond (atom a1, atom a2, view v)
  {
    atm1 = a1;
    atm2 = a2;
    vw = v;

    x1 = v.xyzToScreen (a1.x);
    r1 = radiusRatio * a1.covalentRadius () * v.zoomFactor;
    r1 *= v.perspectiveFactor (x1);

    x2 = v.xyzToScreen (a2.x);
    r2 = radiusRatio * a2.covalentRadius () * v.zoomFactor;
    r2 *= v.perspectiveFactor (x2);
  }
  public double zvalue ()
  {
    return (x1[2] + x2[2]) / 2;
  }
  public void quickpaint (Graphics g)
  {
    Color c1 = atm1.color ();
    Color c2 = atm2.color ();
    // Gray isn't quite dark enough to look good in a wireframe
    if (c1 == Color.gray) c1 = Color.black;
    if (c2 == Color.gray) c2 = Color.black;
    drawBondLine (g, c1, c2, x1, x2);
  }
  public void paint (Graphics g)
  {
    int i;
    double[] v1 = new double[3];
    double[] v2 = new double[3];
    double lensq = 0.0;
    double[] xdiff = new double[3];
    for (i = 0; i < 3; i++)
      {
	v1[i] = x1[i];
	v2[i] = x2[i];
	xdiff[i] = v1[i] - v2[i];
	lensq += xdiff[i] * xdiff[i];
      }
    r1 /= Math.sqrt(lensq);
    for (i = 0; i < 3; i++)
      v1[i] -= r1 * xdiff[i];
    r2 /= Math.sqrt(lensq);
    for (i = 0; i < 3; i++)
      v2[i] += r2 * xdiff[i];
    drawBondLine (g, Color.black, Color.black, v1, v2);
  }
}