package torus;

   /**
   Given list of triangles (each a triple of xyz's) create Java3D object.
   A Shape3D object is created containing one array of triangles.
   The appearance parameter is just passed through.
   Demo for CSE391 course, G. Hart, Sept 2003
   */

import java.lang.Math.*;
import javax.media.j3d.*;
import javax.vecmath.*;

public class makeJ3DObj extends javax.media.j3d.Shape3D{
  public makeJ3DObj(xyz[][] triList, Appearance app) {

    TriangleArray tris = new TriangleArray(3*triList.length,
                          GeometryArray.COORDINATES | GeometryArray.NORMALS);

    for (int i=0; i<triList.length; i++){         // for each given triangle
      xyz v0=triList[i][0];                       // extract vertices
      xyz v1=triList[i][1];
      xyz v2=triList[i][2];

      // compute outward normal for lighting calculations
      xyz norm = xyz.unit(xyz.cross(xyz.minus(v1, v0), xyz.minus(v2, v0)));

      // convert points and normals to vecmath format
      tris.setCoordinate(3*i+0, new Point3f(v0.x, v0.y, v0.z));
      tris.setNormal    (3*i+0, new Vector3f(norm.x, norm.y, norm.z));
      tris.setCoordinate(3*i+1, new Point3f(v1.x, v1.y, v1.z));
      tris.setNormal    (3*i+1, new Vector3f(norm.x, norm.y, norm.z));
      tris.setCoordinate(3*i+2, new Point3f(v2.x, v2.y, v2.z));
      tris.setNormal    (3*i+2, new Vector3f(norm.x, norm.y, norm.z));
    }

    this.setGeometry(tris);              // put triangles in this object
    this.setAppearance(app);             // pass along given appearance
    //this.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);  // allow rotation
  }

}