/**
 * @file   Tetrahedron.java
 * @see    Cube.java
 * <P>
 * modified      Monday 09 November 1998
 * modified by   Robert S Laramee
 * <P>
 * description   The tetrahedron constructor was modified so that it is 
 *               passed a reference to the new BSPTree data structure
 *               Same goes for the makefaces() method.
 */
import java.awt.*;
import java.math.*;
import java.util.*;

//import matrix.*;

class Tetrahedron extends Solid
{
   private	Face	_faces[];
   private	Point4	_vtx[];	// vertices of the cube

   //-------- Tetrahedron ( Matrix4 xform, Color rgb ) -------------
   public Tetrahedron ( Matrix4 xform, Color rgb, BSPTree tree)
   {
       super( xform, rgb );
       makeFaces(tree);
   }
   //-------- Tetrahedron ( Color rgb ) -------------
   public Tetrahedron ( Color rgb, BSPTree tree )
   {
       super( rgb );
       makeFaces(tree);
   }
   //-------- Tetrahedron ( Tetrahedron ) -----------------------------------
   public Tetrahedron ( Tetrahedron l )
   {
       super( l );
   }
   //---------------------- copy ()  -----------------
   public Shape copy ( )
   {
       return new Tetrahedron( this );
   }
    /**
     * ---------------------- makeFaces ( ) 
     * The makeFaces() method was modified.  It gets a reference to the BSP
     * Tree list so each of the new faces can be added to the tree.
     * @param tree -a reference to the BSP Tree
     */
    private void makeFaces (BSPTree tree)  {

	Point4 temp[]={	new Point4(   0,  0,  0 ),	// left lower front
      			new Point4(   1,  0,  0 ),	// lower right front
       			new Point4( 0.5,  1, -0.5 ),	// middle top
       			new Point4(   0, 0.5, -1 ),	// middle bottom back
	               };
	_vtx = temp;
	_faces = new Face[4];
	for (int i = 0; i < _vtx.length; i++) {
	    _vtx[i] = _xform.timesPoint( _vtx[i] );
	}

	Color cols[] =  { _color, 	 	darken(_color, 0.6), 
			  darken(_color, 0.7), 	darken(_color, 0.8) };
	
	_faces[0] = new Face(cols[0],_vtx[0],_vtx[1],_vtx[2]); // front
	_faces[1] = new Face(cols[1],_vtx[0],_vtx[2],_vtx[3]); // left 
	_faces[2] = new Face(cols[2],_vtx[1],_vtx[3],_vtx[2]); // right 
	_faces[3] = new Face(cols[3],_vtx[0],_vtx[3],_vtx[1]); // bottom

	/** add the faces to the BSP Tree */
	for (int i = 0; i < _faces.length; i++) {
	    tree.addFace(new String("tetra_face["+i+"]"), _faces[i]);
	}
    }
   //---------------------- draw (Graphics, Matrix4)  -----------------
   public void draw ( Graphics  g, Matrix4 view )
   {
	for (int i = 0; i < _faces.length; i++ )
	    _faces[i].draw(g , view);
   }
   //---------------------- brighten (Color, double brightenRatio ) --------
   // This uses the "brightenRatio" parameter as a % amount to brighten the
   // Color.  So if you want the Color to be 110% of its current
   // brightness, pass in 1.1 as the brightenRatio parameter.
   // It is actually 

   public Color brighten ( Color rgb, double brightenRatio )
   {
      if ( brightenRatio < 0 )
         brightenRatio = -brightenRatio;
      return new Color ( Math.min(255, (int)(rgb.getRed()*brightenRatio)),
      			 Math.min(255, (int)(rgb.getGreen()*brightenRatio)),
      			 Math.min(255, (int)(rgb.getBlue()*brightenRatio)) );
   }
   //---------------------- darken (Color, double darkenRatio ) --------
   // This uses the "darkenRatio" parameter as a % amount to darken the
   // Color.  So if you want the Color to be 90% of its current
   // brightness, pass in .9 as the darkenRatio parameter.

   public Color darken ( Color rgb, double darkenRatio )
   {
      if ( darkenRatio < 0 )
         darkenRatio = -darkenRatio;
      if ( darkenRatio > 1 )
         darkenRatio = 1; 
      return new Color ( (int)(rgb.getRed()*darkenRatio),
      			 (int)(rgb.getGreen()*darkenRatio),
      			 (int)(rgb.getBlue()*darkenRatio) );
   }
}