zero_pad   xtlang

;creates a copy of the input buffer and pads with zeros
(bind-func zero_pad
  (lambda (buffer:float* buffer_size:i64 padded_buffer:float* padded_size:i64)
    (let ((n:i64 0))
      (dotimes (n padded_size)
        (cond ((< n buffer_size)
                (pset! padded_buffer n (pref buffer n)))
              (else
                (pset! padded_buffer n 0.0))))
      void)))