module Magick::RVG::Transformable

def translate(tx, ty = nil)

to tx.
to all y-coordinates. If ty is omitted it defaults
Add tx to all x-coordinates and ty 
def translate(tx, ty = nil)
  ty ||= tx
  begin
    @transforms << [:translate, [Float(tx), Float(ty)]]
  rescue ArgumentError
    raise ArgumentError, "arguments must be convertable to float (got #{tx.class}, #{ty.class})"
  end
  yield(self) if block_given?
  self
end