init_elements()
z.A = point(0, 0)
z.B = point(12, 0)
z.C = line(z.A, z.B):equilateral().pc
function new_triangle()
  local x = z.A
  z.A = line(z.A, z.B):point(.15)
  z.B = line(z.B, z.C):point(.15)
  z.C = line(z.C, x):point(.15)
end