#!/usr/bin/nawk -f $0
BEGIN {
  if(ARGC < 3) {
    frame_delay = 0.01;
    num_frames = 100
    num_verts = 15
    period = 2
  }
  else {
    num_frames  = ARGV[1];
    num_verts   = ARGV[2];
    frame_delay = ARGV[3];
  }
  pi2= 2*atan2(0,-1);

  printf("%d %d %f\n",num_frames,num_verts,frame_delay); 

  for(k=0;k<num_frames;k++) {
    t1 = (k/num_frames)*pi2;
    t3 = (k/(num_frames-1))*pi2;

    for(j=0;j<num_verts;j++) {
      t2 = (j/num_verts)*pi2;
      t4 = (j/(num_verts-1))*pi2;

      x = sin(t1*2+t2*11) * t2/pi2
      y = cos(t1*4+t2*10) * t2/pi2
      z = sin(t1*6+t2*9) * t2/pi2

#x = cos(t4*8) * sin(t4/2)
#y = sin(t4*8) * sin(t4/2)
      z = cos(t4/2)

#      scale(cos(t3)*0.4+0.6)
#      rotz(t1*4)
      rotx(pi2/3.33)
      roty(t1)

      red   = cos(t4) * 127 + 128
      green = sin(t4) * 127 + 128
      blue  = int((j/(num_verts-1)) * 255)

      printf("%d %f %f %f %02x%02x%02x\n",flags,x,y,z,blue,green,red);
    }
  }
  exit(0);
}

function rotx(angle) {
  y1 = y
  y =  cos(angle) * y1 + sin(angle) * z
  z = -sin(angle) * y1 + cos(angle) * z
}

function roty(angle) {
  z1 = z
  z =  cos(angle)*z1 + sin(angle) * x
  x = -sin(angle)* z1 + cos(angle) * x
}

function rotz(angle) {
  x1 = x
  x =  cos(angle) * x1 + sin(angle) * y
  y = -sin(angle) * x1 + cos(angle) * y
}

function scale(value) {
  x = x * value;
  y = y * value;
  z = z * value;
}
