// cyl1_base.java   compile    javac -cp . cyl1_base.java
//                  execute    java  -cp . cyl1_base
//                             writes      cyl1_base.dat
//                  execute    dat_to_stl cyl1_base.dat cyl1_base.stl
//
//           ********          cylinder covered by triangles
//       ****        ****
//    ***      ****      ***            point numbers
//  **      ***    ***      **
// *       * inside   *       *   outside top pt1+1 .. pt1+16
// |**     |***    ***|     **|
// |  ***  |   ****   |  ***  |        inside top pt3+1 .. pt3+16
// |     ****        ****     |
// |       | ******** |       |
// |       |          |       |
// |       |          |       |
// |       | ******** |       |
// |     ****        ****     |
// |  ***  |   ****   |  ***  |        inside bottom pt2+1 .. pt2+16
// |**     |***    ***|     **|
// *       * inside   *       *  outside bottom pt0+1 .. pt0+16
//  **      ***    ***      **
//    ***      ****      ***
//       ****        ****
//           ********

public class cyl1_base  // make cyl1_base.dat then .stl for 3D printer
{
  public cyl1_base()
  {
    int num_points = 0;
    double data_points[][] = new double[5000][3];
    int num_polys = 0;
    int k = 0; // k index+1/4 = num_polys
    int data_polys[] = new int[5000]; // 3 pt1 pt2 pt3  +1 index
    double pi = 3.14159265358979323846;
    double theta, x, y, z;
    double r = 10.0;
    int pts = 16;
    double dfct = (double)pts/2.0; // 0.0 to 2 pi
    double dtheta = pi/dfct;
    int pt0=0;      // outside bottom
    int pt1=pts;    // outside top
    int pt2=2*pts;  // inside botton
    int pt3=3*pts;  // inside top
    int pt4=4*pts;  // end
    
    System.out.println("cyl1_base.java writing cyl1_base.stl");
    System.out.println("r="+r+", pts="+pts+", dtheta="+dtheta);
    System.out.println("outside bottom points "+(pt0+1)+" to "+(pt1));
    System.out.println("outside top    points "+(pt1+1)+" to "+(pt2));
    
    for(int i=0; i<pts; i++) // generate vertices outside
    {
      theta = (double)i * dtheta;
      x = r * Math.sin(theta);
      y = r * Math.cos(theta);
      z = 0.0; // bottom
      data_points[i+pt0][0] = x;
      data_points[i+pt0][1] = y;
      data_points[i+pt0][2] = z;
      num_points++;
      z = 2.0; // top
      data_points[i+pt1][0] = x;
      data_points[i+pt1][1] = y;
      data_points[i+pt1][2] = z;
      num_points++;
    }

    System.out.println("added points, num_points="+num_points);

//    16    1     2
//    *  -> * ->  *    1 18 17   first
//     \ ^ | \    |    1  2 18
//    ^ \ \v ^\   v
//    |  v \  | v     16 17 32   last
//    *  <- *  <- *   16  1 17
//    32    17    18

    System.out.println(" ");
    System.out.println("generate triangles outside");
    for(int i=0; i<pts; i++) // generate triangles outside
    {
      data_polys[k++] = 3;
      data_polys[k++] = i+pt0+1;
      data_polys[k++] = i+pt1+2;
      data_polys[k++] = i+pt1+1;
      data_polys[k++] = 3;
      data_polys[k++] = i+pt0+1;
      data_polys[k++] = i+pt0+2;
      data_polys[k++] = i+pt1+2;
      if(i==0)
      {
        System.out.println(data_polys[k-8]+"  "+data_polys[k-7]+"  "+
			   data_polys[k-6]+"  "+data_polys[k-5]);
        System.out.println(data_polys[k-4]+"  "+data_polys[k-3]+"  "+
			   data_polys[k-2]+"  "+data_polys[k-1]);
      }
    }
    // fix last two triangles
    data_polys[k-2] = pt0+1;
    data_polys[k-1] = pt1+1;
    data_polys[k-6] = pt1+1;
    num_polys = k/4;
    System.out.println(data_polys[k-8]+"  "+data_polys[k-7]+"  "+
		       data_polys[k-6]+"  "+data_polys[k-5]);
    System.out.println(data_polys[k-4]+"  "+data_polys[k-3]+"  "+
		       data_polys[k-2]+"  "+data_polys[k-1]);
    System.out.println("added triangles, k="+k+", num_polys="+num_polys);
    System.out.println(" ");
    
    System.out.println("inside bottom points "+(pt2+1)+" to "+(pt3));
    System.out.println("inside top    points "+(pt3+1)+" to "+(pt4));

    r = 8.0;
    for(int i=0; i<pts; i++) // generate vertices inside
    {
      theta = (double)i * dtheta;
      x = r * Math.sin(theta);
      y = r * Math.cos(theta);
      z = 0.0; // bottom
      data_points[i+pt2][0] = x;
      data_points[i+pt2][1] = y;
      data_points[i+pt2][2] = z;
      num_points++;
      z = 2.0; // top
      data_points[i+pt3][0] = x;
      data_points[i+pt3][1] = y;
      data_points[i+pt3][2] = z;
      num_points++;
    }

    System.out.println("added points, num_points="+num_points);

//    48     33    34
//    *  <-  * <-  *   33 49 50   first
//       ^  ^ |^   ^   33 50 34
//    |   \ | v \  |
//    v    \     \     48 64 49   last
//    *  ->  *  -> *   48 49 33
//    64     49    50

    System.out.println(" ");
    System.out.println("generate triangles inside");
    for(int i=0; i<pts; i++) // generate triangles inside
    {
      data_polys[k++] = 3;
      data_polys[k++] = i+pt2+1;
      data_polys[k++] = i+pt3+1;
      data_polys[k++] = i+pt3+2;
      data_polys[k++] = 3;
      data_polys[k++] = i+pt2+1;
      data_polys[k++] = i+pt3+2;
      data_polys[k++] = i+pt2+2;
      if(i==0)
      {
        System.out.println(data_polys[k-8]+"  "+data_polys[k-7]+"  "+
			   data_polys[k-6]+"  "+data_polys[k-5]);
        System.out.println(data_polys[k-4]+"  "+data_polys[k-3]+"  "+
			   data_polys[k-2]+"  "+data_polys[k-1]);
      }
    }
    // fix last two triangles
    data_polys[k-1] = pt2+1;
    data_polys[k-2] = pt3+1;
    data_polys[k-5] = pt3+1;
    num_polys = k/4;
    System.out.println(data_polys[k-8]+"  "+data_polys[k-7]+"  "+
		       data_polys[k-6]+"  "+data_polys[k-5]);
    System.out.println(data_polys[k-4]+"  "+data_polys[k-3]+"  "+
		       data_polys[k-2]+"  "+data_polys[k-1]);

    System.out.println("outside bottom points "+(pt0+1)+" to "+(pt1));
    System.out.println("inside  bottom points "+(pt2+1)+" to "+(pt3));

//    16     1     2
//    *  <-  * <-  *    1 33 34   first
//       ^  ^ |^   ^    1 34  2
//    |   \ | v \  |
//    v    \     \     16 48 33   last
//    *  ->  *  -> *   16 33  1
//    48     33    34

    System.out.println(" ");
    System.out.println("generate triangles bottom");
    for(int i=0; i<pts; i++) // generate triangles bottom
    {
      data_polys[k++] = 3;
      data_polys[k++] = i+pt0+1;
      data_polys[k++] = i+pt2+1;
      data_polys[k++] = i+pt2+2;
      data_polys[k++] = 3;
      data_polys[k++] = i+pt0+1;
      data_polys[k++] = i+pt2+2;
      data_polys[k++] = i+pt0+2;
      if(i==0)
      {
        System.out.println(data_polys[k-8]+"  "+data_polys[k-7]+"  "+
			   data_polys[k-6]+"  "+data_polys[k-5]);
        System.out.println(data_polys[k-4]+"  "+data_polys[k-3]+"  "+
			   data_polys[k-2]+"  "+data_polys[k-1]);
      }
    }
    // fix last two triangles
    data_polys[k-1] = pt0+1;
    data_polys[k-2] = pt2+1;
    data_polys[k-5] = pt2+1;
    num_polys = k/4;
    System.out.println(data_polys[k-8]+"  "+data_polys[k-7]+"  "+
		       data_polys[k-6]+"  "+data_polys[k-5]);
    System.out.println(data_polys[k-4]+"  "+data_polys[k-3]+"  "+
		       data_polys[k-2]+"  "+data_polys[k-1]);

    System.out.println("outside top points "+(pt1+1)+" to "+(pt2));
    System.out.println("inside  top points "+(pt3+1)+" to "+(pt4));

//    32     17   18
//    *  ->  * -> *   17 50 49   first
//     \ ^  |  ^  |   17 18 50
//    ^ \ \ v ^ \ v
//    |  v \  |  \    32 49 64   last
//    *  <-  * <- *   32 17 49
//    64     49   50

    System.out.println(" ");
    System.out.println("generate triangles top");
    for(int i=0; i<pts; i++) // generate triangles top
    {
      data_polys[k++] = 3;
      data_polys[k++] = i+pt1+1;
      data_polys[k++] = i+pt3+2;
      data_polys[k++] = i+pt3+1;
      data_polys[k++] = 3;
      data_polys[k++] = i+pt1+1;
      data_polys[k++] = i+pt1+2;
      data_polys[k++] = i+pt3+2;
      if(i==0)
      {
        System.out.println(data_polys[k-8]+"  "+data_polys[k-7]+"  "+
			   data_polys[k-6]+"  "+data_polys[k-5]);
        System.out.println(data_polys[k-4]+"  "+data_polys[k-3]+"  "+
			   data_polys[k-2]+"  "+data_polys[k-1]);
      }
    }
    // fix last two triangles
    data_polys[k-1] = pt3+1;
    data_polys[k-2] = pt1+1;
    data_polys[k-6] = pt3+1;
    num_polys = k/4;
    System.out.println(data_polys[k-8]+"  "+data_polys[k-7]+"  "+
		       data_polys[k-6]+"  "+data_polys[k-5]);
    System.out.println(data_polys[k-4]+"  "+data_polys[k-3]+"  "+
		       data_polys[k-2]+"  "+data_polys[k-1]);

    
    System.out.println("added triangles, k="+k+", num_polys="+num_polys);
    System.out.println(" ");
    
    new datwrite("cyl1_base.dat", data_points, num_points, data_polys, num_polys);
    
  } // end class cyl1_base

  public static void main (String[] args)
  {
    new cyl1_base();
  }
} // end  cyl1_base.java