# effects.rb -- Guile -> Ruby translation -*- snd-ruby -*-

# Translator/Author: Michael Scholz <mi-scholz@users.sourceforge.net>
# Created: Fri Feb 07 23:56:21 CET 2003
# Changed: Thu Apr 15 13:21:42 CEST 2010

# Commentary:
#
# Requires --with-motif and module libxm.so or --with-static-xm!
#
# Tested with Snd 11, Motif 2.2.3, Ruby 1.8.7.
#
# module Effects (see new-effects.scm)
#  plausible_mark_samples
#  map_chan_over_target_with_sync(target, decay, origin_func) do |in| ... end
#  effect_frames(target)
#  
#  effects_squelch_channel(amount, size, snd, chn)
#  effects_echo(input_samps, delay_time, echo_amoung, beg, dur, snd, chn)
#  effects_flecho_1(scaler, secs, input_samps, beg, dur, snd, chn)
#  effects_zecho_1(scaler, secs, frq, amp, input_samps, beg, dur, snd, chn)
#
#  effects_comb_filter(scaler, size, beg, dur, snd, chn)
#  effects_comb_chord(scaler, size, amp, interval_one, interval_two, beg, dur, snd, chn)
#  effects_moog(freq, q, beg, dur, snd, chn)
#  
#  effects_bbp(freq, bw, beg, dur, snd, chn)
#  effects_bbr(freq, bw, beg, dur, snd, chn)
#  effects_bhp(freq, beg, dur, snd, chn)
#  effects_blp(freq, beg, dur, snd, chn)
#  
#  effects_am(freq, en, beg, dur, snd, chn)
#  effects_rm(freq, en, beg, dur, snd, chn)
#
#  effects_cnv(snd0, amp, snd, chn)
#  effects_jc_reverb_1(volume, beg, dur, snd, chn)
#  effects_hello_dentist(frq, amp, beg, dur, snd, chn)
#  effects_fp(srf, osamp, osfrq, beg, dur, snd, chn)
#  effects_position_sound(mono_snd, pos, beg, dur, snd, chn)
#  effects_flange(amount, speed, time, beg, dur, snd, chn)
#  effects_cross_synthesis_1(cross_snd, amp, fftsize, r, beg, dur, snd, chn)
#
# Code:

require "clm"
require "snd-xm"
require "env"
require "extensions"
require "xm-enved"
require "rubber"
include Rubber
include Math
require "hooks"

$effects_menu = false           # for prefs

unless $mark_hook.member?("mark-buttons-effects-hook")
  mark_hook_proc = lambda do | |
    flag = marks?
    $mark_buttons.each do |w| set_sensitive(w, flag) end
  end
  
  $mark_hook.add_hook!("mark-buttons-effects-hook") do |id, snd, chn, reason|
    mark_hook_proc.call
  end

  $after_graph_hook.add_hook!("mark-buttons-effects-hook") do |snd, chn|
    mark_hook_proc.call
  end
end

module Effects
  def plausible_mark_samples
    snd = selected_sound
    chn = selected_channel
    if ms = marks(snd, chn)
      ms = ms.map do |x| mark_sample(x) end.sort
      if ms.length < 2
        Snd.display("mark-related action requires two marks")
        false
      else
        if ms.length == 2
          ms
        else
          lw = left_sample(snd, chn)
          rw = right_sample(snd, chn)
          cw = cursor(snd, chn)
          favor = if cw >= lw and cw <= rw
                    cw
                  else
                    0.5 * (lw + rw)
                  end
          centered_points = lambda do |points|
            if points.length == 2
              points
            else
              p1, p2, p3 = points[0, 3]
              if (p1 - favor).abs < (p3 - favor).abs
                [p1, p2]
              else
                centered_points.call(points[1..-1])
              end
            end
          end
          centered_points.call(ms)
        end
      end
    else
      Snd.display("mark-related action requires marks")
      false
    end
  end

  def map_chan_over_target_with_sync(target, decay, origin_func, &func)
    okay = case target
           when :sound
             (sounds or (Snd.display("no sound") and false))
           when :selection
             selection? or (Snd.display("no selection") and false)
           when :marks
             (sounds or marks(selected_sound, selected_channel).length < 2 or
               (Snd.display("no marks") and false))
           else
             true
           end
    if okay
      snc = sync()
      ssnd = selected_sound
      schn = selected_channel
      ms = (target == :marks and plausible_mark_samples)
      beg = case target
            when :sound
              0
            when :selection
              selection_position
            when :cursor
              cursor(selected_sound, selected_channel)
            else
              (ms ? ms[0] : 0)
            end
      overlap = (decay ? (srate().to_f * decay).round : 0)
      sndlst, chnlst = (snc > 0 ? all_chans() : [[ssnd], [schn]])
      sndlst.zip(chnlst) do |snd, chn|
        dur = if target == :sound or target == :cursor
                frames(snd, chn) - 1
              elsif target == :selection and selection?
                selection_position + selection_frames
              else
                ms[1]
              end
        if sync(snd) == snc
          map_chan(func.call(dur - beg), beg, dur + overlap, origin_func.call(dur - beg), snd, chn)
        end
      end
    end
  end

  def effect_frames(target)
    case target
    when :sound
      frames() - 1
    when :selection
      selection_frames
    else
      if ms = plausible_mark_samples
        y = ms.shift
        ms.each do |x| y -= x end
        1 + y.abs
      else
        1
      end
    end
  end

  def effects_squelch_channel(amount, size, snd = false, chn = false)
    f0 = make_moving_average(size)
    f1 = make_moving_average(size, :initial_element, 1.0)
    map_channel(lambda do |y|
                  y * moving_average(f1, ((moving_average(f0, y * y) < amount) ? 0.0 : 1.0))
                end, 0, false, snd, chn, false, format("%s(%s, %s", get_func_name, amount, size))
  end

  def effects_echo(input_samps, delay_time, echo_amount,
                   beg = 0, dur = false, snd = false, chn = false)
    del = make_delay((delay_time.to_f * srate(snd)).round)
    samp = 0
    samps = (input_samps or dur or frames(snd, chn))
    amp = echo_amount
    map_channel_rb(beg, dur, snd, chn, false,
                   format("%s(%s, %s, %s, %s, %s",
                          get_func_name, input_samps, delay_time,
                          echo_amount, beg, dur)) do |inval|
      samp += 1
      inval + delay(del, amp * (tap(del) + ((samp <= samps) ? inval : 0.0)))
    end
  end
    
  def effects_flecho_1(scaler, secs, input_samps,
                       beg = 0, dur = false, snd = false, chn = false)
    flt = make_fir_filter(:order, 4, :xcoeffs, [0.125, 0.25, 0.25, 0.125].to_vct)
    del = make_delay((secs.to_f * srate(snd)).round)
    samp = 0
    samps = (input_samps or dur or frames(snd, chn))
    amp = scaler
    map_channel_rb(beg, dur, snd, chn, false,
                   format("%s(%s, %s, %s, %s, %s",
                          get_func_name, scaler, secs, input_samps, beg, dur)) do |inval|
      samp += 1
      inval + delay(del, fir_filter(flt, amp * (tap(del) + ((samp <= samps) ? inval : 0.0))))
    end
  end

  def effects_zecho_1(scaler, secs, frq, amp, input_samps,
                      beg = 0, dur = false, snd = false, chn = false)
    os = make_oscil(:frequency, frq)
    len = (secs.to_f * srate()).round
    del = make_delay(len, :max_size, (len + amp + 1).to_i)
    samp = 0
    samps = (input_samps or dur or frames(snd, chn))
    map_channel_rb(beg, dur, snd, chn, false,
                   format("%s(%s, %s, %s, %s, %s, %s, %s",
                          get_func_name, scaler, secs, frq,
                          amp, input_samps, beg, dur)) do |inval|
      samp += 1
      inval + delay(del, amp * (tap(del) + ((samp <= samps) ? inval : 0.0)), amp * oscil(os))
    end
  end

  def effects_comb_filter(scaler, size, beg = 0, dur = false, snd = false, chn = false)
    delay_line = Vct.new(size)
    delay_loc = 0
    map_channel_rb(beg, dur, snd, chn, false,
                   format("%s(%s, %s, %s, %s", get_func_name, scaler, size, beg, dur)) do |inval|
      result = delay_line[delay_loc]
      delay_line[delay_loc] = inval + scaler * result
      delay_loc += 1
      if delay_loc >= size then delay_loc = 0 end
      result
    end
  end

  def effects_comb_chord(scaler, size, amp, interval_one, interval_two,
                         beg = 0, dur = false, snd = false, chn = false)
    c1 = make_comb(scaler, size)
    c2 = make_comb(scaler, size * interval_one)
    c3 = make_comb(scaler, size * interval_two)
    map_channel_rb(beg, dur, snd, chn, false,
                   format("%s(%s, %s, %s, %s, %s, %s, %s",
                          get_func_name, scaler, size, amp,
                          interval_one, interval_two, beg, dur)) do |inval|
      amp * (comb(c1, inval) + comb(c2, inval) + comb(c3, inval))
    end
  end

  def effects_moog(freq, q, beg = 0, dur = false, snd = false, chn = false)
    gen = make_moog_filter(freq, q)
    map_channel_rb(beg, dur, snd, chn, false,
                   format("%s(%s, %s, %s, %s", get_func_name, freq, q, beg, dur)) do |inval|
      moog_filter(gen, inval)
    end
  end

  def effects_bbp(freq, bw, beg = 0, dur = false, snd = false, chn = false)
    flt = make_butter_band_pass(freq, bw)
    clm_channel(flt, beg, dur, snd, chn, false, false,
                format("%s(%s, %s, %s, %s", get_func_name, freq, bw, beg, dur))
  end

  def effects_bbr(freq, bw, beg = 0, dur = false, snd = false, chn = false)
    flt = make_butter_band_reject(freq, bw)
    clm_channel(flt, beg, dur, snd, chn, false, false,
                format("%s(%s, %s, %s, %s", get_func_name, freq, bw, beg, dur))
  end

  def effects_bhp(freq, beg = 0, dur = false, snd = false, chn = false)
    flt = make_butter_high_pass(freq)
    clm_channel(flt, beg, dur, snd, chn, false, false,
                format("%s(%s, %s, %s", get_func_name, freq, beg, dur))
  end

  def effects_blp(freq, beg = 0, dur = false, snd = false, chn = false)
    flt = make_butter_low_pass(freq)
    clm_channel(flt, beg, dur, snd, chn, false, false,
                format("%s(%s, %s, %s", get_func_name, freq, beg, dur))
  end

  def effects_am(freq, en, beg = 0, dur = false, snd = false, chn = false)
    os = make_oscil(:frequency, freq)
    e = (en and make_env(:envelope, en, :length, (dur or frames(snd, chn))))
    func = if e
             lambda do |inval| amplitude_modulate(1.0, inval, env(e) * oscil(os)) end
           else
             lambda do |inval| amplitude_modulate(1.0, inval, oscil(os)) end
           end
    map_channel(func, beg, dur, snd, chn, false,
                format("%s(%s, %s, %s, %s",
                       get_func_name, freq, (en ? en.inspect : "false"), beg, dur))
  end
  
  def effects_rm(freq, gliss_env, beg = 0, dur = false, snd = false, chn = false)
    os = make_oscil(:frequency, freq)
    e = (gliss_env and make_env(:envelope, gliss_env, :length, (dur or frames(snd, chn))))
    func = if e
             lambda do |inval| inval * env(e) * oscil(os) end
           else
             lambda do |inval| inval * oscil(os) end
           end
    map_channel(func, beg, dur, snd, chn, false,
                format("%s(%s, %s, %s, %s",
                       get_func_name, freq, (gliss_env ? gliss_env.inspect : "false"), beg, dur))
  end

  def effects_cnv(snd0, amp, snd = false, chn = false)
    snd0 = Snd.snd
    flt_len = frames(snd0)
    total_len = flt_len + frames(snd, chn)
    cnv = make_convolve(:filter, channel2vct, 0, flt_len, snd0)
    sf = make_sampler(0, snd, chn)
    out_data = Vct.new(total_len) do |i|
      convolve(cnv, lambda { |dir| next_sample(sf) })
    end
    free_sampler(sf)
    out_data.scale!(amp)
    max_samp = out_data.peak
    vct2channel(out_data, 0, total_len, snd, chn, false,
                format("%s(%s, %s", get_func_name, snd0, amp))
    if max_samp > 1.0 then set_y_bounds([-max_samp, max_samp], snd, chn) end
    max_samp
  end

  def effects_jc_reverb(input_samps, volume)
    allpass1 = make_all_pass(-0.7, 0.7, 1051)
    allpass2 = make_all_pass(-0.7, 0.7, 337)
    allpass3 = make_all_pass(-0.7, 0.7, 113)
    comb1 = make_comb(0.742, 4799)
    comb2 = make_comb(0.733, 4999)
    comb3 = make_comb(0.715, 5399)
    comb4 = make_comb(0.697, 5801)
    outdel1 = make_delay((0.013 * srate()).round)
    comb_sum = 0.0
    comb_sum_1 = 0.0
    comb_sum_2 = 0.0
    samp = 0
    lambda do |inval|
      allpass_sum = all_pass(allpass3,
                             all_pass(allpass2,
                                      all_pass(allpass1,
                                               (samp < input_samps ? inval : 0.0))))
      samp += 1
      comb_sum_2 = comb_sum_1
      comb_sum_1 = comb_sum
      comb_sum = (comb(comb1, allpass_sum) + comb(comb2, allpass_sum) + \
                  comb(comb3, allpass_sum) + comb(comb4, allpass_sum))
      inval + volume * delay(outdel1, comb_sum)
    end
  end

  def effects_jc_reverb_1(volume, beg = 0, dur = false, snd = false, chn = false)
    map_channel(effects_jc_reverb((dur or frames(snd, chn)), volume),
                beg, dur, snd, chn, false, format("%s(%s, %s, %s", get_func_name, volume, beg, dur))
  end
  
  def effects_hello_dentist(frq, amp, beg = 0, dur = false, snd = false, chn = false)
    rn = make_rand_interp(:frequency, frq, :amplitude, amp)
    i = j = 0
    len = (dur or frames(snd, chn)) 
    in_data = channel2vct(beg, len, snd, chn)
    out_len = (len.to_f * (1.0 + 2.0 * amp)).round
    out_data = make_vct(out_len)
    rd = make_src(:srate, 1.0, :input, lambda { |dir|
                    val = (i.between?(0, len - 1) ? in_data[i] : 0.0)
                    i += dir
                    val
                  })
    until i == len or j == out_len
      out_data[j] = src(rd, rand_interp(rn))
      j += 1
    end
    vct2channel(out_data, beg, j, snd, chn, false,
                format("%s(%s, %s, %s, %s",
                       get_func_name, frq, amp, beg, (len == frames(snd, chn) ? "false" : len)))
  end

  def effects_fp(srf, osamp, osfrq, beg = 0, dur = false, snd = false, chn = false)
    os = make_oscil(:frequency, osfrq)
    sr = make_src(:srate, srf)
    sf = make_sampler(beg)
    len = (dur or frames(snd, chn))
    out_data = Vct.new(len) do |i|
      src(sr, osamp * oscil(os),
          lambda do |dir|
            if dir > 0
              next_sample(sf)
            else
              previous_sample(sf)
            end
          end)
    end
    free_sampler(sf)
    vct2channel(out_data, beg, len, snd, chn, false,
                format("%s(%s, %s, %s, %s, %s",
                       get_func_name, srf, osamp, osfrq, beg,
                       (len == frames(snd, chn) ? "false" : len)))
  end

  def effects_position_sound(mono_snd, pos, beg = 0, dur = false, snd = false, chn = false)
    assert_type((sound?(mono_snd) or mono_snd == false), mono_snd, 0, "a sound index")
    assert_type((array?(pos) or number?(pos)), pos, 1, "an array or a number")
    len = frames(mono_snd)
    reader1 = make_sampler(0, mono_snd)
    if number?(pos)
      map_channel_rb(0, len, snd, chn, false,
                     format("%s(%s, %s", get_func_name, mono_snd, pos)) do |inval|
        inval + pos * read_sample(reader1)
      end
    else
      if array?(pos)
        e1 = make_env(:envelope, pos, :length, len)
        if number?(chn) and chn == 1
          map_channel(0, len, snd, chn, false,
                      format("%s(%s, %s", get_func_name, mono_snd, pos.inspect)) do |inval|
            inval + env(e1) * read_sample(reader1)
          end
        else
          map_channel(0, len, snd, chn, false,
                      format("%s(%s, %s", get_func_name, mono_snd, pos.inspect)) do |inval|
            inval + (1.0 - env(e1)) * read_sample(reader1)
          end
        end
      end
    end
  end

  def effects_flange(amount, speed, time, beg = 0, dur = false, snd = false, chn = false)
    ri = make_rand_interp(:frequency, speed, :amplitude, amount)
    len = (time.to_f * srate(snd)).round
    del = make_delay(:size, len, :max_size, (len + amount + 1).round)
    map_channel_rb(beg, dur, snd, chn, false,
                   format("%s(%s, %s, %s, %s, %s",
                          get_func_name, amount, speed, time, beg,
                          (number?(dur) and
                             (not dur == frames(snd, chn)) ? dur : "false"))) do |inval|
      0.75 * (inval + delay(del, inval, rand_interp(ri)))
    end
  end

  def effects_cross_synthesis_1(cross_snd, amp, fftsize, r,
                                beg = 0, dur = false, snd = false, chn = false)
    map_channel(effects_cross_synthesis(Snd.snd(cross_snd), amp, fftsize, r),
                beg, dur, snd, chn, false,
                format("%s(%s, %s, %s, %s, %s, %s",
                       get_func_name, cross_snd, amp, fftsize, r, beg, dur))
  end

  def effects_remove_dc(snd = false, chn = false)
    lastx = lasty = 0.0
    map_channel_rb(0, false, snd, chn, false, "effects_remove_dc(") do |inval|
      lasty = inval + (0.999 * lasty - lastx)
      lastx = inval
      lasty
    end
  end

  def effects_compand(snd = false, chn = false)
    tbl = vct(-1.00, -0.96, -0.90, -0.82, -0.72, -0.60, -0.45, -0.25,
              0.00, 0.25, 0.45, 0.60, 0.72, 0.82, 0.90, 0.96, 1.00)
    map_channel_rb(0, false, snd, chn, false, "effects_compand(") do |inval|
      array_interp(tbl, 8.0 + 8.0 * inval)
    end
  end
  
  #
  # --- Amplitude Effects ---
  #
  class Gain
    def initialize(label)
      @label = label
      @amount = 1.0
      @dlg = nil
      @target = :sound
      @envelope = nil
    end

    def inspect
      format("%s (%1.2f)", @label, @amount)
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_amount = 1.0
        sliders = Array.new(1)
        fr = nil
        @dlg = make_dialog(@label,
                           :info, "Move the slider to change the gain scaling amount",
                           :reset_cb, lambda do |w, c, i|
                             @envelope.envelope = [0.0, 1.0, 1.0, 1.0]
                             set_scale_value(sliders[0].scale, @amount = init_amount, 100.0)
                           end) do |w, c, i|
          with_env = ((@envelope.envelope != [0.0, 1.0, 1.0, 1.0]) and @envelope.scale(@amount))
          case @target
          when :sound
            with_env ? env_sound(with_env) : scale_by(@amount)
          when :selection
            if selection?
              with_env ? env_selection(with_env) : scale_selection_by(@amount)
            else
              snd_warning("no selection")
            end
          else
            if pts = plausible_mark_samples
              if with_env
                env_sound(with_env, pts[0], pts[1] - pts[0])
              else
                pos = false
                len = false
                if selection?
                  pos = selection_position
                  len = selection_frames
                end
                set_selection_member?(false)
                set_selection_position(pts[0])
                set_selection_frames(pts[1] - pts[0])
                scale_selection_by(@amount)
                if integer?(pos)
                  set_selection_position(pos)
                  set_selection_frames(len)
                else
                  set_selection_member?(false)
                end
              end
            end
          end
        end
        sliders[0] = @dlg.add_slider("gain", 0.0, init_amount, 5.0, 100) do |w, c, i|
          @amount = get_scale_value(w, i, 100.0)
        end
        frame = @dlg.add_frame([RXmNheight, 200])
        @dlg.add_target() do |t| @target = t end
        activate_dialog(@dlg.dialog)
        @envelope = make_xenved("gain", frame,
                                :envelope, [0.0, 1.0, 1.0, 1.0],
                                :axis_bounds, [0.0, 1.0, 0.0, 1.0])
      else
        activate_dialog(@dlg.dialog)
      end
    end
  end

  class Normalize
    def initialize(label)
      @label = label
      @amount = 1.0
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f)", @label, @amount)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_amount = 1.0
        sliders = Array.new(1)
        @dlg = make_dialog(@label,
                           :info, "Normalize scales amplitude to the normalize amount. \
Move the slider to change the scaling amount.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @amount = init_amount, 100.0)
                           end) do |w, c, i|
          case @target
          when :sound
            scale_to(@amount)
          when :selection
            selection? ? scale_selection_to(@amount) : snd_warning("no selection")
          else
            if pts = plausible_mark_samples
              pos = false
              len = false
              if selection?
                pos = selection_position
                len = selection_frames
              end
              set_selection_member?(false)
              set_selection_position(pts[0])
              set_selection_frames(pts[1] - pts[0])
              scale_selection_to(@amount)
              if integer?(pos)
                set_selection_position(pos)
                set_selection_frames(len)
              else
                set_selection_member?(false)
              end
            end
          end
        end
        sliders[0] = @dlg.add_slider("normalize", 0.0, init_amount, 1.0, 100) do |w, c, i|
          @amount = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end

  class Gate
    def initialize(label)
      @label = label
      @amount = 0.01
      @dlg = nil
      @size = 128
    end

    def inspect
      format("%s (%1.2f)", @label, @amount)
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_amount = 0.01
        sliders = Array.new(1)
        @dlg = make_dialog(@label,
                           :info, "Move the slider to change the gate intensity. \
Higher values gate more of the sound.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @amount = init_amount, 1000.0)
                           end) do |w, c, i|
          if (snc = sync()) > 0
            sndlst, chnlst = all_chans()
            sndlst.zip(chnlst) do |snd, chn|
              effects_squelch_channel(@amount * @amount, @size, snd, chn) if sync(snd) == snc
            end
          else
            effects_squelch_channel(@amount * @amount, @size, selected_sound, selected_channel)
          end
        end
        sliders[0] = @dlg.add_slider("gate", 0.0, init_amount, 0.1, 1000) do |w, c, i|
          @amount = get_scale_value(w, i, 1000.0)
        end
      end
      activate_dialog(@dlg.dialog)
    end
  end

  #
  # --- Delay Effects ---
  #
  class Echo
    def initialize(label)
      @label = label
      @delay_time = 0.5
      @amount = 0.2
      @dlg = nil
      @target = :sound
      @truncate = true
    end

    def inspect
      format("%s (%1.2f %1.2f)", @label, @delay_time, @amount)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_delay_time = 0.5
        init_amount = 0.2
        sliders = Array.new(2)
        @dlg = make_dialog(@label,
                           :info, "The sliders change the delay time and echo amount.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @delay_time = init_delay_time, 100.0)
                             set_scale_value(sliders[1].scale, @amount = init_amount, 100.0)
                           end) do |w, c, i|
          map_chan_over_target_with_sync(@target,
                                         (!@truncate and 4 * @delay_time),
                                         lambda { |s|
                                           format("effects_echo(%s, %s, %s",
                                                  (@target == :sound ? false : s),
                                                  @delay_time, @amount)
                                         }) do |s|
            size = (@delay_time * srate()).round
            d = make_delay(size)
            samp = 0
            lambda do |inval|
              samp += 1
              t = if samp <= s
                    inval
                  else
                    0.0
                  end
              inval + delay(d, @amount * (tap(d) + t))
            end
          end 
        end
        sliders[0] = @dlg.add_slider("delay time", 0.0, init_delay_time, 2.0, 100) do |w, c, i|
          @delay_time = get_scale_value(w, i, 100.0)
        end
        sliders[1] = @dlg.add_slider("echo amount", 0.0, init_amount, 1.0, 100) do |w, c, i|
          @amount = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
        @dlg.add_toggle() do |t| @truncate = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end

  class Filtered_echo
    def initialize(label)
      @label = label
      @scaler = 0.5
      @delay = 0.9
      @dlg = nil
      @target = :sound
      @truncate = true
    end

    def inspect
      format("%s (%1.2f %1.2f)", @label, @scaler, @delay)
    end
    
    def flecho_1(scaler, secs, input_samps)
      flt = make_fir_filter(:order, 4, :xcoeffs, [0.125, 0.25, 0.25, 0.125].to_vct)
      del = make_delay((secs.to_f * srate(snd)).round)
      samp = 0
      lambda do |inval|
        samp += 1
        inval + delay(del,
                      fir_filter(flt, scaler * (tap(del) + (samp <= input_samps ? inval : 0.0))))
      end
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_scaler = 0.5
        init_del = 0.9
        sliders = Array.new(2)
        @dlg = make_dialog(@label,
                           :info, "Move the sliders to the filter scaler and the \
delay time in seconds.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @scaler = init_scaler, 100.0)
                             set_scale_value(sliders[1].scale, @delay = init_del, 100.0)
                           end) do |w, c, i|
          map_chan_over_target_with_sync(@target,
                                         (!@truncate and 4 * @delay),
                                         lambda { |s|
                                           format("effects_flecho_1(%s, %s, %s",
                                                  @scaler, @delay, (@target == :sound ? false : s))
                                         }) do |s|
            flecho_1(@scaler, @delay, s)
          end
        end
        sliders[0] = @dlg.add_slider("filter scaler", 0.0, init_scaler, 1.0, 100) do |w, c, i|
          @scaler = get_scale_value(w, i, 100.0)
        end
        sliders[1] = @dlg.add_slider("delay time (secs)", 0.0, init_del, 3.0, 100) do |w, c, i|
          @delay = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
        @dlg.add_toggle() do |t| @truncate = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end

  class Modulated_echo
    def initialize(label)
      @label = label
      @scaler = 0.5
      @delay = 0.75
      @freq = 6
      @amp = 10.0
      @dlg = nil
      @target = :sound
      @truncate = true
    end

    def inspect
      format("%s (%1.2f %1.2f %1.2f %1.2f)", @label, @scaler, @delay, @freq, @amp)
    end

    def zecho_1(scaler, secs, frq, amp, input_samps)
      os = make_oscil(:frequency, frq)
      len = (secs.to_f * srate()).round
      del = make_delay(len, :max_size, (len + amp + 1).to_i)
      samp = 0
      lambda do |inval|
        samp += 1
        inval + delay(del,
                      scaler * (tap(del) + (samp <= input_samps ? inval : 0.0)), amp * oscil(os))
      end
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_scaler = 0.5
        init_del = 0.75
        init_freq = 6
        init_amp = 10.0
        sliders = Array.new(4)
        @dlg = make_dialog(@label,
                           :info, "Move the sliders to set the echo scaler, \
the delay time in seconds, the modulation frequency, and the echo amplitude.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @scaler = init_scaler, 100.0)
                             set_scale_value(sliders[1].scale, @delay = init_del, 100.0)
                             set_scale_value(sliders[2].scale, @freq = init_freq, 100.0)
                             set_scale_value(sliders[3].scale, @amp = init_amp, 100.0)
                           end) do |w, c, i|
          map_chan_over_target_with_sync(@target,
                                         (!@truncate and 4 * @delay),
                                         lambda { |s|
                                           format("effects_zecho_1(%s, %s, %s, %s, %s",
                                                  @scaler, @delay, @freq, @amp,
                                                  (@target == :sound ? false : s))
                                         }
                                         ) do |s|
            zecho_1(@scaler, @delay, @freq, @amp, s)
          end
        end
        sliders[0] = @dlg.add_slider("echo scaler", 0.0, init_scaler, 1.0, 100) do |w, c, i|
          @scaler = get_scale_value(w, i, 100.0)
        end
        sliders[1] = @dlg.add_slider("delay time (secs)", 0.0, init_del, 3.0, 100) do |w, c, i|
          @delay = get_scale_value(w, i, 100.0)
        end
        sliders[2] = @dlg.add_slider("modulation frequency",
                                     0.0, init_freq, 100.0, 100) do |w, c, i|
          @freq = get_scale_value(w, i, 100.0)
        end
        sliders[3] = @dlg.add_slider("modulation amplitude",
                                     0.0, init_amp, 100.0, 100) do |w, c, i|
          @amp = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
        @dlg.add_toggle() do |t| @truncate = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end

  #
  # --- Filters ---
  #
  class Band_pass
    def initialize(label)
      @label = label
      @freq = 1000
      @bw = 100
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f %d)", @label, @freq, @bw)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_freq = 1000
        init_bw = 100
        sliders = Array.new(2)
        @dlg = make_dialog(@label,
                           :info, "Butterworth band-pass filter. \
Move the slider to change the center frequency and bandwidth.",
                           :reset_cb, lambda do |w, c, i|
                             @freq = init_freq
                             set_scale_value(sliders[0].scale, scale_log2linear(20, @freq, 22050))
                             change_label(sliders[0].label, "%1.2f" % @freq)
                             set_scale_value(sliders[1].scale, @bw = init_bw)
                           end) do |w, c, i|
          flt = make_butter_band_pass(@freq, @bw)
          case @target
          when :sound
            filter_sound(flt, false, false, false, false,
                         format("effects_bbp(%s, %s, 0, false", @freq, @bw))
          when :selection
            filter_selection(flt)
          else
            ms = plausible_mark_samples
            bg = ms[0]
            nd = ms[1] - ms[0] + 1
            clm_channel(flt, bg, nd, false, false, false, false,
                        format("effects_bbp(%s, %s, %s, %s", @freq, @bw, bg, nd))
          end
        end
        sliders[0] = @dlg.add_slider("center frequency",
                                     20, init_freq, 22050, 1, :log) do |w, c, i|
          @freq = scale_linear2log(20, Rvalue(i), 22050)
        end
        sliders[1] = @dlg.add_slider("bandwidth", 0, init_bw, 1000) do |w, c, i|
          @bw = get_scale_value(w, i)
        end
        @dlg.add_target([["entire sound", :sound, true],
                         ["selection", :selection, false]]) do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end

  class Band_reject
    def initialize(label)
      @label = label
      @freq = 100
      @bw = 100
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f %d)", @label, @freq, @bw)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_freq = 100
        init_bw = 100
        sliders = Array.new(2)
        @dlg = make_dialog(@label,
                           :info, "Butterworth band-reject filter. \
Move the slider to change the center frequency and bandwidth.",
                           :reset_cb, lambda do |w, c, i|
                             @freq = init_freq
                             set_scale_value(sliders[0].scale, scale_log2linear(20, @freq, 22050))
                             change_label(sliders[0].label, "%1.2f" % @freq)
                             set_scale_value(sliders[1].scale, @bw = init_bw)
                           end) do |w, c, i|
          flt = make_butter_band_reject(@freq, @bw)
          case @target
          when :sound
            filter_sound(flt, false, false, false, false,
                         format("effects_bbr(%s, %s, 0, false", @freq, @bw))
          when :selection
            filter_selection(flt)
          else
            ms = plausible_mark_samples
            bg = ms[0]
            nd = ms[1] - ms[0] + 1
            clm_channel(flt, bg, nd, false, false, false, false,
                        format("effects_bbr(%s, %s, %s, %s", @freq, @bw, bg, nd))
          end
        end
        sliders[0] = @dlg.add_slider("center frequency",
                                     20, init_freq, 22050, 1, :log) do |w, c, i|
          @freq = scale_linear2log(20, Rvalue(i), 22050)
        end
        sliders[1] = @dlg.add_slider("bandwidth", 0, init_bw, 1000) do |w, c, i|
          @bw = get_scale_value(w, i)
        end
        @dlg.add_target([["entire sound", :sound, true],
                         ["selection", :selection, false]]) do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  class High_pass
    def initialize(label)
      @label = label
      @freq = 100
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f)", @label, @freq)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_freq = 100
        sliders = Array.new(1)
        @dlg = make_dialog(@label,
                           :info, "Butterworth high-pass filter. \
Move the slider to change the high-pass cutoff frequency.",
                           :reset_cb, lambda do |w, c, i|
                             @freq = init_freq
                             set_scale_value(sliders[0].scale, scale_log2linear(20, @freq, 22050))
                             change_label(sliders[0].label, "%1.2f" % @freq)
                           end) do |w, c, i|
          flt = make_butter_high_pass(@freq)
          case @target
          when :sound
            filter_sound(flt, false, false, false, false,
                         format("effects_bhp(%s, 0, false", @freq))
          when :selection
            filter_selection(flt)
          else
            ms = plausible_mark_samples
            bg = ms[0]
            nd = ms[1] - ms[0] + 1
            clm_channel(flt, bg, nd, false, false, false, false,
                        format("effects_bhp(%s, %s, %s", @freq, bg, nd))
          end
        end
        sliders[0] = @dlg.add_slider("high-pass cutoff frequency",
                                     20, init_freq, 22050, 1, :log) do |w, c, i|
          @freq = scale_linear2log(20, Rvalue(i), 22050)
        end
        @dlg.add_target([["entire sound", :sound, true],
                         ["selection", :selection, false]]) do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  class Low_pass
    def initialize(label)
      @label = label
      @freq = 1000
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f)", @label, @freq)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_freq = 1000
        sliders = Array.new(1)
        @dlg = make_dialog(@label,
                           :info, "Butterworth low-pass filter. \
Move the slider to change the low-pass cutoff frequency.",
                           :reset_cb, lambda do |w, c, i|
                             @freq = init_freq
                             set_scale_value(sliders[0].scale, scale_log2linear(20, @freq, 22050))
                             change_label(sliders[0].label, "%1.2f" % @freq)
                           end) do |w, c, i|
          flt = make_butter_low_pass(@freq)
          case @target
          when :sound
            filter_sound(flt, false, false, false, false,
                         format("effects_blp(%s, 0, false", @freq))
          when :selection
            filter_selection(flt)
          else
            ms = plausible_mark_samples
            bg = ms[0]
            nd = ms[1] - ms[0] + 1
            clm_channel(flt, bg, nd, false, false, false, false,
                        format("effects_blp(%s, %s, %s", @freq, bg, nd))
          end
        end
        sliders[0] = @dlg.add_slider("low-pass cutoff frequency",
                                     20, init_freq, 22050, 1, :log) do |w, c, i|
          @freq = scale_linear2log(20, Rvalue(i), 22050)
        end
        @dlg.add_target([["entire sound", :sound, true],
                         ["selection", :selection, false]]) do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  class Comb
    def initialize(label)
      @label = label
      @scaler = 0.1
      @size = 50
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f %d)", @label, @scaler, @size)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_scaler = 0.1
        init_size = 50
        sliders = Array.new(2)
        @dlg = make_dialog(@label,
                           :info, "Move the slider to change the comb scaler and size.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @scaler = init_scaler, 100.0)
                             set_scale_value(sliders[1].scale, @size = init_size)
                           end) do |w, c, i|
          map_chan_over_target_with_sync(@target, false,
                                         lambda { |s|
                                           format("effects_comb_filter(%s, %s", @scaler, @size)
                                         }) do |ignored|
            comb_filter(@scaler, @size)
          end
        end
        sliders[0] = @dlg.add_slider("scaler", 0.0, init_scaler, 1.0, 100) do |w, c, i|
          @scaler = get_scale_value(w, i, 100.0)
        end
        sliders[1] = @dlg.add_slider("size", 1, init_size, 100) do |w, c, i|
          @size = get_scale_value(w, i)
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  class Comb_chord
    def initialize(label)
      @label = label
      @scaler = 0.95
      @size = 60
      @amp = 0.3
      @interval_one = 0.75
      @interval_two = 1.20
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f %d %1.2f %1.2f %1.2f)",
             @label, @scaler, @size, @amp, @interval_one, @interval_two)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_scaler = 0.95
        init_size = 60
        init_amp = 0.3
        init_one = 0.75
        init_two = 1.20
        sliders = Array.new(5)
        @dlg = make_dialog(@label,
                           :info, "Comb chord filter:
Creates chords by using filters at harmonically related sizes. \
Move the sliders to set the comb chord parameters.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @scaler = init_scaler, 100.0)
                             set_scale_value(sliders[1].scale, @size = init_size)
                             set_scale_value(sliders[2].scale, @amp = init_amp, 100.0)
                             set_scale_value(sliders[3].scale, @interval_one = init_one, 100.0)
                             set_scale_value(sliders[4].scale, @interval_two = init_two, 100.0)
                           end) do |w, c, i|
          map_chan_over_target_with_sync(@target, false,
                                         lambda { |s|
                                           format("effects_comb_chord(%s, %s, %s, %s, %s",
                                                  @scaler, @size, @amp,
                                                  @interval_one, @interval_two)
                                         }) do |ignored|
            comb_chord(@scaler, @size, @amp, @interval_one, @interval_two)
          end
        end
        sliders[0] = @dlg.add_slider("chord scaler", 0.0, init_scaler, 1.0, 100) do |w, c, i|
          @scaler = get_scale_value(w, i, 100.0)
        end
        sliders[1] = @dlg.add_slider("chord size", 1, init_size, 100) do |w, c, i|
          @size = get_scale_value(w, i)
        end
        sliders[2] = @dlg.add_slider("amplitude", 0.0, init_amp, 1.0, 100) do |w, c, i|
          @amp = get_scale_value(w, i, 100.0)
        end
        sliders[3] = @dlg.add_slider("interval one", 0.0, init_one, 2.0, 100) do |w, c, i|
          @interval_one = get_scale_value(w, i, 100.0)
        end
        sliders[4] = @dlg.add_slider("interval two", 0.0, init_two, 2.0, 100) do |w, c, i|
          @interval_two = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end

  class Moog_filter
    def initialize(label)
      @label = label
      @cutoff_freq = 10000
      @resonance = 0.5
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f %1.2f)", @label, @cutoff_freq, @resonance)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_freq = 10000
        init_resonance = 0.5
        sliders = Array.new(2)
        @dlg = make_dialog(@label,
                           :info, "Moog filter:
Moog-style 4-pole lowpass filter with 24db/oct rolloff and variable resonance. \
Move the sliders to set the filter cutoff frequency and resonance.",
                           :reset_cb, lambda do |w, c, i|
                             @cutoff_freq = init_freq
                             set_scale_value(sliders[0].scale,
                                             scale_log2linear(20, @cutoff_freq, 22050))
                             change_label(sliders[0].label, "%1.2f" % @cutoff_freq)
                             set_scale_value(sliders[1].scale, @resonance = init_resonance, 100.0)
                           end) do |w, c, i|
          map_chan_over_target_with_sync(@target, false,
                                         lambda { |s|
                                           format("effects_moog(%s, %s",
                                                  @cutoff_freq, @resonance)
                                         }) do |ignored|
            moog(@cutoff_freq, @resonance)
          end
        end
        sliders[0] = @dlg.add_slider("cutoff frequency",
                                     20, init_freq, 22050, 1, :log) do |w, c, i|
          @cutoff_freq = scale_linear2log(20, Rvalue(i), 22050)
        end
        sliders[1] = @dlg.add_slider("resonance", 0.0, init_resonance, 1.0, 100) do |w, c, i|
          @resonance = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  #
  # --- Frequency Effects ---
  #
  class Adaptive
    def initialize(label)
      @label = label
      @size = 4
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%d)", @label, @size)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_size = 4
        sliders = Array.new(1)
        @dlg = make_dialog(@label,
                           :info, "Move the slider to change the saturation scaling factor.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @size = init_size)
                           end) do |w, c, i|
          map_chan_over_target_with_sync(@target, false,
                                         lambda { |s|
                                           format("adsat(%s", @size)
                                         }) do |ignored|
            mn = 0.0
            mx = 0.0
            n = 0
            vals = make_vct(@size)
            lambda do |val|
              if n == @size
                @size.times do |ii|
                  if vals[ii] >= 0.0
                    vals[ii] = mx
                  else
                    vals[ii] = mn
                  end
                end
                n, mx, mn = 0, 0.0, 0.0
                vals
              else
                vals[n] = val
                mx = [mx, val].max
                mn = [mn, val].min
                n += 1
                false
              end
            end
          end
        end
        sliders[0] = @dlg.add_slider("adaptive saturation size", 0, init_size, 10) do |w, c, i|
          @size = get_scale_value(w, i).round
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end

  class Sample_rate
    def initialize(label)
      @label = label
      @amount = 0.0
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f)", @label, @amount)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_amount = 0.0
        sliders = Array.new(1)
        @dlg = make_dialog(@label,
                           :info, "Move the slider to change the sample rate. \
Values greater than 1.0 speed up file play, negative values reverse it.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @amount = init_amount, 100.0)
                           end) do |w, c, i|
          case @target
          when :sound
            src_sound(@amount)
          when :selection
            selection? ? src_selection(@amount) : snd_warning("no selection")
          end
        end
        sliders[0] = @dlg.add_slider("sample rate", -2.0, init_amount, 2.0, 100) do |w, c, i|
          @amount = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target([["entire sound", :sound, true],
                         ["selection", :selection, false]]) do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  class Time_pitch
    def initialize(label)
      @label = label
      @dlg = nil
      @target = :sound
      @time_scale = 1.0
      @hop_size = 0.05
      @segment_length = 0.15
      @ramp_scale = 0.5
      @pitch_scale = 1.0
    end

    def inspect
      format("%s (%1.2f %1.2f)", @label, @time_scale, @pitch_scale)
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        time_scale = 1.0
        hop_size = 0.05
        seg_length = 0.15
        ramp_scale = 0.5
        pitch_scale = 1.0
        sliders = Array.new(5)
        @dlg = make_dialog(@label,
                           :info, "Move the sliders to change the time/pitch scaling parameters.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @time_scale = time_scale, 100.0)
                             set_scale_value(sliders[1].scale, @hop_size = hop_size, 100.0)
                             set_scale_value(sliders[2].scale, @segment_length = seg_length, 100.0)
                             set_scale_value(sliders[3].scale, @ramp_scale = ramp_scale, 100.0)
                             set_scale_value(sliders[4].scale, @pitch_scale = pitch_scale, 100.0)
                           end) do |w, c, i|
          snd = selected_sound
          save_controls(snd)
          reset_controls(snd)
          set_speed_control(@pitch_scale, snd)
          new_time = @pitch_scale * @time_scale.to_f
          if new_time != 1.0
            set_expand_control?(true, snd)
            set_expand_control(new_time, snd)
            set_expand_control_hop(@hop_size, snd)
            set_expand_control_length(@segment_length, snd)
            set_expand_control_ramp(@ramp_scale, snd)
          end
          if @target == :marks
            if ms = plausible_mark_samples
              apply_controls(snd, 0, ms[0], 1 + (ms[1] - ms[0]))
            end
          else
            apply_controls(snd, (@target == :sound ? 0 : 2))
          end
          restore_controls(snd)
        end
        sliders[0] = @dlg.add_slider("time scale", 0.0, time_scale, 5.0, 100) do |w, c, i|
          @time_scale = get_scale_value(w, i, 100.0)
        end
        sliders[1] = @dlg.add_slider("hop size", 0.0, hop_size, 1.0, 100) do |w, c, i|
          @hop_size = get_scale_value(w, i, 100.0)
        end
        sliders[2] = @dlg.add_slider("segment length", 0.0, seg_length, 0.5, 100) do |w, c, i|
          @segment_length = get_scale_value(w, i, 100.0)
        end
        sliders[3] = @dlg.add_slider("ramp scale", 0.0, ramp_scale, 0.5, 1000) do |w, c, i|
          @ramp_scale = get_scale_value(w, i, 100.0)
        end
        sliders[4] = @dlg.add_slider("pitch scale", 0.0, pitch_scale, 5.0, 100) do |w, c, i|
          @pitch_scale = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  class Src_timevar
    # Time-varying sample rate conversion (resample) (KSM)
    def initialize(label)
      @label = label
      @scale = 1.0
      @dlg = nil
      @target = :sound
      @envelope = nil
    end

    def inspect
      format("%s (%1.2f)", @label, @scale)
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_scale = 1.0
        init_env = 
        sliders = Array.new(1)
        fr = nil
        @dlg = make_dialog(@label,
                           :info, "Move the slider to change the src-timevar scaling amount.",
                           :reset_cb, lambda do |w, c, i|
                             @envelope.envelope = [0.0, 1.0, 1.0, 1.0]
                             set_scale_value(sliders[0].scale, @scale = init_scale, 100.0)
                           end) do |w, c, i|
          env = @envelope.scale(@scale)
          case @target
          when :sound
            src_sound(env)
          when :selection
            if selection_member?(selected_sound)
              src_selection(env)
            else
              snd_warning("no selection")
            end
          else
            if pts = plausible_mark_samples
              beg = pts[0]
              len = pts[1] - beg
              src_channel(make_env(env, :length, len), beg, len, selected_sound)
            end
          end
        end
        sliders[0] = @dlg.add_slider("resample factor", 0.0, init_scale, 10.0, 100) do |w, c, i|
          @scale = get_scale_value(w, i, 100.0)
        end
        frame = @dlg.add_frame([RXmNheight, 200])
        @dlg.add_target() do |t| @target = t end
        activate_dialog(@dlg.dialog)
        # out-of-range error if envelope hits 0.0
        # therefore y0 = 0.0001
        @envelope = make_xenved("src-timevar", frame,
                                :envelope, [0.0, 1.0, 1.0, 1.0],
                                :axis_bounds, [0.0, 1.0, 0.0001, 1.0])
      end
      activate_dialog(@dlg.dialog)
    end
  end

  #
  # --- Modulation Effects ---
  #
  class Amplitude_modulation
    def initialize(label)
      @label = label
      @amount = 100.0
      @dlg = nil
      @target = :sound
      @envelope = nil
    end

    def inspect
      format("%s (%1.2f)", @label, @amount)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_amount = 100.0
        sliders = Array.new(1)
        fr = nil
        @dlg = make_dialog(@label,
                           :info, "Move the slider to change the modulation amount.",
                           :reset_cb, lambda do |w, c, i|
                             @envelope.envelope = [0.0, 1.0, 1.0, 1.0]
                             set_scale_value(sliders[0].scale, @amount = init_amount)
                           end) do |w, c, i|
          need_env = (@envelope.envelope != [0.0, 1.0, 1.0, 1.0])
          map_chan_over_target_with_sync(@target, false,
                                         lambda { |s|
                                           format("effects_am(%s, %s",
                                                  @amount,
                                                  ((need_env and @envelope.envelope) ?
                                                   @envelope.envelope.inspect : "false"))
                                         }) do |ignored|
            os = make_oscil(@amount)
            e = (need_env and make_env(@envelope.envelope, :length, effect_frames(@target)))
            if need_env
              lambda do |inval|
                amplitude_modulate(1.0, inval, env(e) * oscil(os))
              end
            else
              lambda do |inval|
                amplitude_modulate(1.0, inval, oscil(os))
              end
            end
          end
        end
        sliders[0] = @dlg.add_slider("amplitude modulation", 0.0, init_amount, 1000.0) do |w, c, i|
          @amount = get_scale_value(w, i)
        end
        frame = @dlg.add_frame([RXmNheight, 200])
        @dlg.add_target() do |t| @target = t end
        activate_dialog(@dlg.dialog)
        @envelope = make_xenved("amplitude modulation", frame,
                                :envelope, [0.0, 1.0, 1.0, 1.0],
                                :axis_bounds, [0.0, 1.0, 0.0, 1.0])
      else
        activate_dialog(@dlg.dialog)
      end
    end
  end  

  class Ring_modulation
    def initialize(label)
      @label = label
      @frequency = 100
      @radians = 100
      @dlg = nil
      @target = :sound
      @envelope = nil
    end

    def inspect
      format("%s (%d %d)", @label, @frequency, @radians)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_frequency = 100
        init_radians = 100
        sliders = Array.new(2)
        fr = nil
        @dlg = make_dialog(@label,
                           :info, "Move the sliders to change the modulation parameters.",
                           :reset_cb, lambda do |w, c, i|
                             @envelope.envelope = [0.0, 1.0, 1.0, 1.0]
                             set_scale_value(sliders[0].scale, @frequency = init_frequency)
                             set_scale_value(sliders[1].scale, @radians = init_radians)
                           end) do |w, c, i|
          need_env = (@envelope.envelope != [0.0, 1.0, 1.0, 1.0])
          map_chan_over_target_with_sync(@target, false,
                                         lambda { |s|
                                           format("effects_rm(%s, %s",
                                                  @frequency,
                                                  ((need_env and @envelope.envelope) ?
                                                   @envelope.envelope.inspect : "false"))
                                         }) do |ignored|
            os = make_oscil(@frequency)
            e = (need_env and make_env(@envelope.envelope, :length, effect_frames(@target)))
            len = frames()
            genv = make_env([0, 0, 1, hz2radians(@radians)], :length, len)
            if need_env
              lambda do |inval| inval * (env(e) * oscil(os)) end
            else
              lambda do |inval| inval * oscil(os) end
            end
          end
        end
        sliders[0] = @dlg.add_slider("modulation frequency", 0, init_frequency, 1000) do |w, c, i|
          @frequency = get_scale_value(w, i)
        end
        sliders[1] = @dlg.add_slider("modulation radians", 0, init_radians, 360) do |w, c, i|
          @radians = get_scale_value(w, i)
        end
        frame = @dlg.add_frame([RXmNheight, 200])
        @dlg.add_target() do |t| @target = t end
        activate_dialog(@dlg.dialog)
        @envelope = make_xenved("ring modulation", frame,
                                :envelope, [0.0, 1.0, 1.0, 1.0],
                                :axis_bounds, [0.0, 1.0, 0.0, 1.0])
      else
        activate_dialog(@dlg.dialog)
      end
    end
  end
  
  #
  # --- Reverbs ---
  #
  class Nrev
    def initialize(label)
      @label = label
      @amount = 0.1
      @filter = 0.5
      @feedback = 1.09
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f %1.2f %1.2f)", @label, @amount, @filter, @feedback)
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_amount = 0.1
        init_filter = 0.5
        init_feedback = 1.09
        sliders = Array.new(3)
        @dlg = make_dialog(@label,
                           :info, "Reverberator from Michael McNabb. \
Adds reverberation scaled by reverb amount, lowpass filtering, and feedback. \
Move the sliders to change the reverb parameters.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @amount = init_amount, 100.0)
                             set_scale_value(sliders[1].scale, @filter = init_filter, 100.0)
                             set_scale_value(sliders[2].scale, @feedback = init_feedback, 100.0)
                           end) do |w, c, i|
          snd = selected_sound
          save_controls(snd)
          reset_controls(snd)
          set_reverb_control?(true, snd)
          set_reverb_control_scale(@amount, snd)
          set_reverb_control_lowpass(@filter, snd)
          set_reverb_control_feedback(@feedback, snd)
          if @target == :marks
            if ms = plausible_mark_samples
              apply_controls(snd, 0, ms[0], 1 + (ms[1] - ms[0]))
            end
          else
            apply_controls(snd, (@target == :sound ? 0 : 2))
          end
          restore_controls(snd)
        end
        sliders[0] = @dlg.add_slider("reverb amount", 0.0, init_amount, 1.0, 100) do |w, c, i|
          @amount = get_scale_value(w, i, 100.0)
        end
        sliders[1] = @dlg.add_slider("reverb filter", 0.0, init_filter, 1.0, 100) do |w, c, i|
          @filter = get_scale_value(w, i, 100.0)
        end
        sliders[2] = @dlg.add_slider("reverb feedback", 0.0, init_feedback, 1.25, 100) do |w, c, i|
          @feedback = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  class Chowning
    def initialize(label)
      @label = label
      @decay = 2.0
      @volume = 0.1
      @dlg = nil
      @target = :sound
      @truncate = true
    end

    def inspect
      format("%s (%1.2f %1.2f)", @label, @decay, @volume)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_decay = 2.0
        init_volume = 0.1
        sliders = Array.new(2)
        @dlg = make_dialog(@label,
                           :info, "Nice reverb from John Chowning. \
Move the sliders to change the reverb parameters.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @decay = init_decay, 100.0)
                             set_scale_value(sliders[1].scale, @volume = init_volume, 100.0)
                           end) do |w, c, i|
          map_chan_over_target_with_sync(@target, (!@truncate and @decay),
                                         lambda { |s|
                                           format("effects_jc_reverb_1(%s, %s", s, @volume)
                                         }) do |s|
            effects_jc_reverb(s, @volume)
          end
        end
        sliders[0] = @dlg.add_slider("decay duration", 0.0, init_decay, 10.0, 100) do |w, c, i|
          @decay = get_scale_value(w, i, 100.0)
        end
        sliders[1] = @dlg.add_slider("reverb volume", 0.0, init_volume, 1.0, 100) do |w, c, i|
          @volume = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
        @dlg.add_toggle() do |t| @truncate = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end
  
  class Convolution
    def initialize(label)
      @label = label
      @sound_one = 0
      @sound_two = 1
      @amp = 0.01
      @dlg = nil
    end

    def inspect
      format("%s (%d %d %1.2f)", @label, @sound_one, @sound_two, @amp)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_one = 0
        init_two = 1
        init_amp = 0.01
        sliders = Array.new(3)
        @dlg = make_dialog(@label,
                           :info, "Very simple convolution. \
Move the sliders to set the numbers of the soundfiles to be convolved and the \
amount for the amplitude scaler.

Output will be scaled to floating-point values, resulting in very large \
(but not clipped) amplitudes. Use the Normalize amplitude effect to rescale the output.

The convolution data file typically defines a natural reverberation source, \
and the output from this effect can provide very striking reverb effects. \
You can find convolution data files on sites listed at \
http://www.bright.net/~dlphilp/linux_csound.html under Impulse Response Data.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @sound_one = init_one)
                             set_scale_value(sliders[1].scale, @sound_two = init_two)
                             set_scale_value(sliders[2].scale, @amp = init_amp, 100.0)
                           end) do |w, c, i|
          if sound?(@sound_one) and sound?(@sound_two)
            effects_cnv(@sound_one, @sound_two, @amp)
          else
            snd_warning(format("sound-one: %s, sound-two: %s",
                               sound?(@sound_one).to_s, sound?(@sound_two).to_s))
          end
        end
        sliders[0] = @dlg.add_slider("impulse response file", 0, init_one, 24) do |w, c, i|
          @sound_one = get_scale_value(w, i).round
        end
        sliders[1] = @dlg.add_slider("sound file", 0, init_two, 24) do |w, c, i|
          @sound_two = get_scale_value(w, i).round
        end
        sliders[2] = @dlg.add_slider("amplitude", 0.0, init_amp, 0.1, 100) do |w, c, i|
          @amp = get_scale_value(w, i, 100.0)
        end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  #
  # --- Various and Miscellaneous ---
  #
  class Placed
    def initialize(label)
      @label = label
      @mono_snd = 0
      @stereo_snd = 1
      @pan_pos = 45
      @dlg = nil
      @target = :sound
      @envelope = nil
    end

    def inspect
      format("%s (%d %d %d)", @label, @mono_snd, @stereo_snd, @pan_pos)
    end

    def place_sound(pan_env)
      len = frames(@mono_snd)
      if number?(pan_env)
        effects_position_sound(@mono_snd, pos, @stereo_snd, 1)
        effects_position_sound(@mono_snd, 1.0 - pos, @stereo_snd, 0)
      else
        effects_position_sound(@mono_snd, pan_env, @stereo_snd, 1)
        effects_position_sound(@mono_snd, pan_env, @stereo_snd, 0)
      end
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_mono_snd = 0
        init_stereo_snd = 1
        init_pan_pos = 45
        sliders = Array.new(3)
        @dlg = make_dialog(@label,
                           :info, "Mixes mono sound into stereo sound field.",
                           :reset_cb, lambda do |w, c, i|
                             @envelope.envelope = [0.0, 1.0, 1.0, 1.0]
                             set_scale_value(sliders[0].scale, @mono_snd = init_mono_snd)
                             set_scale_value(sliders[1].scale, @stereo_snd = init_stereo_snd)
                             set_scale_value(sliders[2].scale, @pan_pos = init_pan_pos)
                           end) do |w, c, i|
          if (e = @envelope.envelope) != [0.0, 1.0, 1.0, 1.0]
            place_sound(e)
          else
            place_sound(@pan_pos)
          end
        end
        sliders[0] = @dlg.add_slider("mono sound", 0, init_mono_snd, 50) do |w, c, i|
          @mono_snd = get_scale_value(w, i).round
        end
        sliders[1] = @dlg.add_slider("stereo sound", 0, init_stereo_snd, 50) do |w, c, i|
        @stereo_snd = get_scale_value(w, i).round
        end
        sliders[2] = @dlg.add_slider("pan position", 0, init_pan_pos, 90) do |w, c, i|
        @pan_pos = get_scale_value(w, i)
        end
        frame = @dlg.add_frame([RXmNheight, 200])
        @dlg.add_target() do |t| @target = t end
        activate_dialog(@dlg.dialog)
        @envelope = make_xenved("panning", frame,
                                :envelope, [0.0, 1.0, 1.0, 1.0],
                                :axis_bounds, [0.0, 1.0, 0.0, 1.0])
      end
      activate_dialog(@dlg.dialog)
    end
  end

  class Add_silence
    def initialize(label)
      @label = label
      @amount = 1.0
      @dlg = nil
    end

    def inspect
      format("%s (%1.2f)", @label, @amount)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_amount = 1.0
        sliders = Array.new(1)
        @dlg = make_dialog(@label,
                           :info, "Move the slider to change the number of seconds \
of silence added at the cursor position.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @amount = init_amount, 100.0)
                           end) do |w, c, i|
          insert_silence(cursor(), (srate().to_f * @amount).round)
        end
        sliders[0] = @dlg.add_slider("silence", 0.0, init_amount, 5.0, 100) do |w, c, i|
          @amount = get_scale_value(w, i, 100.0)
        end
      end
      activate_dialog(@dlg.dialog)
    end
  end

  class Contrast
    def initialize(label)
      @label = label
      @amount = 1.0
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f)", @label, @amount)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_amount = 1.0
        sliders = Array.new(1)
        @dlg = make_dialog(@label,
                           :info, "Move the slider to change the contrast intensity.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @amount = init_amount, 100.0)
                           end) do |w, c, i|
          peak = maxamp()
          save_controls
          reset_controls
          set_contrast_control?(true)
          set_contrast_control(@amount)
          set_contrast_control_amp(1.0 / peak)
          set_amp_control(peak)
          if @target == :marks
            if ms = plausible_mark_samples
              apply_controls(selected_sound, 0, ms[0], 1 + (ms[1] - ms[0]))
            end
          else
            apply_controls(selected_sound, (@target == :sound ? 0 : 2))
          end
          restore_controls
        end
        sliders[0] = @dlg.add_slider("contrast enhancement",
                                     0.0, init_amount, 10.0, 100) do |w, c, i|
          @amount = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end

  class Cross_synthesis
    def initialize(label)
      @label = label
      @sound = 1
      @amp = 0.5
      @fft_size = 128
      @radius = 6.0
      @dlg = nil
      @default_fft_widget = nil
      @target = :sound
    end

    def inspect
      format("%s (%d %1.2f %d %1.2f)", @label, @sound, @amp, @fft_size, @radius)
    end

    def effects_cross_synthesis(cross_snd, amp, fftsize, r)
      freq_inc = fftsize / 2
      fdr = make_vct(fftsize)
      fdi = make_vct(fftsize)
      spectr = make_vct(freq_inc)
      inctr = 0
      ctr = freq_inc
      radius = 1.0 - r / fftsize.to_f
      bin = srate() / fftsize.to_f
      formants = make_array(freq_inc) do |i| make_formant(i * bin, radius) end
      lambda do |inval|
        if ctr == freq_inc
          fdr = channel2vct(inctr, fftsize, cross_snd, 0)
          inctr += freq_inc
          spectrum(fdr, fdi, false, 2)
          fdr.subtract!(spectr)
          fdr.scale!(1.0 / freq_inc)
          ctr = 0
        end
        ctr += 1
        spectr.add!(fdr)
        amp * formant_bank(spectr, formants, inval)
      end
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_sound = 1
        init_amp = 0.5
        init_fft_size = 128
        init_radius = 6.0
        sliders = Array.new(3)
        @dlg = make_dialog(@label,
                           :info, "The sliders set the number of the soundfile \
to be cross_synthesized, the synthesis amplitude, the FFT size, and the radius value.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @sound = init_sound)
                             set_scale_value(sliders[1].scale, @amp = init_amp, 100.0)
                             @fft_size = init_fft_size
                             RXmToggleButtonSetState(@default_fft_widget, true, true)
                             set_scale_value(sliders[2].scale, @radius = init_radius, 100.0)
                           end) do |w, c, i|
          if sound?(@sound)
            map_chan_over_target_with_sync(@target, false,
                                           lambda { |s|
                                             format("effects_cross_synthesis_1(%s, %s, %s, %s",
                                                    @sound, @amp, @fft_size, @radius)
                                           }) do |ignored|
              effects_cross_synthesis(@sound, @amp, @fft_size, @radius)
            end
          else
            snd_warning(format("cross-snd: %s", sound?(@sound).to_s))
          end
        end
        sliders[0] = @dlg.add_slider("input sound", 0, init_sound, 20) do |w, c, i|
          @sound = get_scale_value(w, i).round
        end
        sliders[1] = @dlg.add_slider("amplitude", 0.0, init_amp, 1.0, 100) do |w, c, i|
          @amp = get_scale_value(w, i, 100.0)
        end
        sliders[2] = @dlg.add_slider("radius", 0.0, init_radius, 360.0, 100) do |w, c, i|
          @radius = get_scale_value(w, i, 100.0)
        end
        frame = @dlg.add_frame([RXmNpositionIndex, 2])
        frm = RXtCreateManagedWidget("frm", RxmFormWidgetClass, frame,
                                     [RXmNleftAttachment, RXmATTACH_FORM,
                                      RXmNrightAttachment, RXmATTACH_FORM,
                                      RXmNtopAttachment, RXmATTACH_FORM,
                                      RXmNbottomAttachment, RXmATTACH_FORM,
                                      RXmNbackground, basic_color])
        rc = RXtCreateManagedWidget("rc", RxmRowColumnWidgetClass, frm,
                                    [RXmNorientation, RXmHORIZONTAL,
                                     RXmNradioBehavior, true,
                                     RXmNradioAlwaysOne, true,
                                     RXmNentryClass, RxmToggleButtonWidgetClass,
                                     RXmNisHomogeneous, true,
                                     RXmNleftAttachment, RXmATTACH_FORM,
                                     RXmNrightAttachment, RXmATTACH_FORM,
                                     RXmNtopAttachment, RXmATTACH_FORM,
                                     RXmNbottomAttachment, RXmATTACH_NONE,
                                     RXmNbackground, basic_color])
        RXtCreateManagedWidget("FFT size", RxmLabelWidgetClass, frm,
                               [RXmNalignment, RXmALIGNMENT_BEGINNING,
                                RXmNtopAttachment, RXmATTACH_WIDGET,
                                RXmNtopWidget, rc,
                                RXmNbackground, basic_color])
        [64, 128, 256, 512, 1024, 4096].each do |s|
          button = RXtCreateManagedWidget(s.to_s, RxmToggleButtonWidgetClass, rc,
                                          [RXmNbackground, basic_color,
                                           RXmNvalueChangedCallback,
                                           [lambda do |w, c, i| @fft_size = c if Rset(i) end, s],
                                           RXmNset, (s == @fft_size)])
          if s == @fft_size
            @default_fft_widget = button
          end
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  class Flange
    def initialize(label)
      @label = label
      @speed = 2.0
      @amount = 5.0
      @time = 0.001
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f %1.2f %1.3f)", @label, @speed, @amount, @time)
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_speed = 2.0
        init_amount = 5.0
        init_time = 0.001
        sliders = Array.new(3)
        @dlg = make_dialog(@label,
                           :info, "Move the sliders to change the flange speed, amount, and time.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @speed = init_speed, 10.0)
                             set_scale_value(sliders[1].scale, @amount = init_amount, 10.0)
                             set_scale_value(sliders[2].scale, @time = init_time, 100.0)
                           end) do |w, c, i|
          map_chan_over_target_with_sync(@target, false,
                                         lambda { |s|
                                           format("effects_flange(%s, %s, %s",
                                                  @amount, @speed, @time)
                                         }) do |ignored|
            ri = make_rand_interp(:frequency, @speed, :amplitude, @amount)
            len = (@time.to_f * srate()).round
            del = make_delay(len, :max_size, (len + @amount + 1).to_i)
            lambda do |inval|
              0.75 * (inval + delay(del, inval, rand_interp(ri)))
            end
          end
        end
        sliders[0] = @dlg.add_slider("flange speed", 0.0, init_speed, 100.0, 10) do |w, c, i|
          @speed = get_scale_value(w, i, 10.0)
        end
        sliders[1] = @dlg.add_slider("flange amount", 0.0, init_amount, 100.0, 10) do |w, c, i|
          @amount = get_scale_value(w, i, 10.0)
        end
        sliders[2] = @dlg.add_slider("flange time", 0.0, init_time, 1.0, 100) do |w, c, i|
          @time = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  class Randomize_phase
    def initialize(label)
      @label = label
      @amp_scaler = 3.14
      @dlg = nil
    end

    def inspect
      format("%s (%1.2f)", @label, @amp_scaler)
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_scaler = 3.14
        sliders = Array.new(1)
        @dlg = make_dialog(@label,
                           :info, "Move the slider to change the randomization amplitude scaler.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @amp_scaler = init_scaler, 100.0)
                           end) do |w, c, i|
          rotate_phase(lambda do |x| kernel_rand(@amp_scaler) end)
        end
        sliders[0] = @dlg.add_slider("amplitude scaler", 0.0, init_scaler, 100.0, 100) do |w, c, i|
          @amp_scaler = get_scale_value(w, i, 100.0)
        end
      end
      activate_dialog(@dlg.dialog)
    end
  end

  class Robotize
    def initialize(label)
      @label = label
      @samp_rate = 1.0
      @osc_amp = 0.3
      @osc_freq = 20
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f %1.2f %1.2f)", @label, @samp_rate, @osc_amp, @osc_freq)
    end
    
    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_rate = 1.0
        init_amp = 0.3
        init_freq = 20
        sliders = Array.new(3)
        @dlg = make_dialog(@label,
                           :info, "Move the sliders to set the sample rate, \
oscillator amplitude, and oscillator frequency.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @samp_rate = init_rate, 100.0)
                             set_scale_value(sliders[1].scale, @osc_amp = init_amp, 100.0)
                             set_scale_value(sliders[2].scale, @osc_freq = init_freq, 100.0)
                           end) do |w, c, i|
          ms = (@target == :marks and plausible_mark_samples)
          effects_fp(@samp_rate, @osc_amp, @osc_freq,
                     case @target
                     when :sound
                       0
                     when :selection
                       selection_position
                     else
                       ms[0]
                     end, case @target
                          when :sound
                            frames
                          when :selection
                            selection_frames
                          else
                            ms[1] - ms[0]
                          end)
        end
        sliders[0] = @dlg.add_slider("sample rate", 0.0, init_rate, 2.0, 100) do |w, c, i|
          @samp_rate = get_scale_value(w, i, 100.0)
        end
        sliders[1] = @dlg.add_slider("oscillator amplitude", 0.0, init_amp, 1.0, 100) do |w, c, i|
          @osc_amp = get_scale_value(w, i, 100.0)
        end
        sliders[2] = @dlg.add_slider("oscillator frequency", 0.0, init_freq, 60, 100) do |w, c, i|
          @osc_freq = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  class Rubber_sound
    def initialize(label)
      @label = label
      @factor = 1.0
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f)", @label, @factor)
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_factor = 1.0
        sliders = Array.new(1)
        @dlg = make_dialog(@label,
                           :info, "Stretches or contracts the time of a sound. \
Move the slider to change the stretch factor.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @factor = init_factor, 100.0)
                           end) do |w, c, i|
          rubber_sound(@factor)
        end
        sliders[0] = @dlg.add_slider("stretch factor", 0.0, init_factor, 5.0, 100) do |w, c, i|
          @factor = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end  

  class Wobble
    def initialize(label)
      @label = label
      @frequency = 50
      @amplitude = 0.5
      @dlg = nil
      @target = :sound
    end

    def inspect
      format("%s (%1.2f %1.2f)", @label, @frequency, @amplitude)
    end

    def post_dialog
      unless @dlg.kind_of?(Dialog) and widget?(@dlg.dialog)
        init_freq = 50
        init_amp = 0.5
        sliders = Array.new(2)
        @dlg = make_dialog(@label,
                           :info, "Move the sliders to set the wobble frequency and amplitude.",
                           :reset_cb, lambda do |w, c, i|
                             set_scale_value(sliders[0].scale, @frequency = init_freq, 100.0)
                             set_scale_value(sliders[1].scale, @amplitude = init_amp, 100.0)
                           end) do |w, c, i|
          ms = (@target == :marks and plausible_mark_samples)
          effects_hello_dentist(@frequency, @amplitude,
                                case @target
                                when :sound
                                  0
                                when :selection
                                  selection_position
                                else
                                  ms[0]
                                end, case @target
                                     when :sound
                                       frames
                                     when :selection
                                       selection_frames
                                     else
                                       ms[1] - ms[0]
                                     end)
        end
        sliders[0] = @dlg.add_slider("wobble frequency", 0, init_freq, 100, 100) do |w, c, i|
          @frequency = get_scale_value(w, i, 100.0)
        end
        sliders[1] = @dlg.add_slider("wobble amplitude", 0.0, init_amp, 1.0, 100) do |w, c, i|
          @amplitude = get_scale_value(w, i, 100.0)
        end
        @dlg.add_target() do |t| @target = t end
      end
      activate_dialog(@dlg.dialog)
    end
  end
end

#
# example menu
#
if provided? :xm
  unless defined? $__private_snd_menu__ and $__private_snd_menu__
    include Effects

    snd_main = make_snd_menu("Effects") do
      cascade("Amplitude Effects") do
        entry(Gain, "Gain")
        entry(Normalize, "Normalize")
        entry(Gate, "Gate")
      end
      cascade("Delay Effects") do
        entry(Echo, "Echo")
        entry(Filtered_echo, "Filtered echo")
        entry(Modulated_echo, "Modulated echo")
      end
      cascade("Filter Effects") do
        entry(Band_pass, "Band-pass filter")
        entry(Band_reject, "Band-reject filter")
        entry(High_pass, "High-pass filter")
        entry(Low_pass, "Low-pass filter")
        entry(Comb, "Comb filter")
        entry(Comb_chord, "Comb chord filter")
        entry(Moog_filter, "Moog filter")
      end
      cascade("Frequency Effects") do
        entry(Adaptive, "Adaptive saturation")
        entry(Sample_rate, "Sample rate conversion")
        entry(Time_pitch, "Time/pitch scaling")
        entry(Src_timevar, "Src-Timevar")
      end
      cascade("Modulation Effects") do
        entry(Amplitude_modulation, "Amplitude modulation")
        entry(Ring_modulation, "Ring modulation")
      end
      cascade("Reverbs") do
        entry(Nrev, "McNabb reverb")
        entry(Chowning, "Chowning reverb")
        entry(Convolution, "Convolution")
      end
      cascade("Various") do
        entry(Placed, "Place sound")
        entry(Add_silence, "Add silence")
        entry(Contrast, "Contrast enhancement")
        entry(Cross_synthesis, "Cross synthesis")
        entry(Flange, "Flange")
        entry(Randomize_phase, "Randomize phase")
        entry(Robotize, "Robotize")
        entry(Rubber_sound, "Rubber sound")
        entry(Wobble, "Wobble")
      end
      separator
      entry("Octave-down") do down_oct(2) end
      entry("Remove clicks") do
        find_click = lambda do |loc|
          reader = make_sampler(loc)
          samp0 = samp1 = samp2 = 0.0
          samps = make_vct(10)
          len = frames()
          samps_ctr = 0
          ret = false
          ctr = loc
          until c_g? or ctr == len
            samp0, samp1 = samp1, samp2
            samp2 = next_sample(reader)
            samps[samps_ctr] = samp0
            if samps_ctr < 9
              samps_ctr += 1
            else
              samps_ctr = 0
            end
            local_max = [0.1, vct_peak(samps)].max
            if ((samp0 - samp1).abs > local_max) and
                ((samp1 - samp2).abs > local_max) and
                ((samp0 - samp2).abs < (local_max / 2))
              ret = ctr - 1
              break
            end
            ctr += 1
          end
          ret
        end
        remove_click = lambda do |loc|
          if click = find_click.call(loc) and (not c_g?)
            smooth_sound(click - 2, 4)
            remove_click.call(click + 2)
          end
        end
        remove_click.call(2)
      end
      entry("Remove DC") do effects_remove_dc end
      entry("Spiker") do spike end
      entry("Compand") do effects_compand end
      entry("Invert") do scale_by(-1) end
      entry("Reverse") do reverse_sound end
      entry("Null phase") do zero_phase end
    end

    set_label_sensitive(menu_widgets[Top_menu_bar], "Effects", ((sounds() or []).length > 1))
    
    unless $open_hook.member?("effects-menu-hook")
      $open_hook.add_hook!("effects-menu-hook") do |snd| 
        set_label_sensitive(menu_widgets[Top_menu_bar], "Effects", true)
        false
      end
      
      $close_hook.add_hook!("effects-menu-hook") do |snd|
        set_label_sensitive(menu_widgets[Top_menu_bar], "Effects", ((sounds() or []).length > 1))
        false
      end
    end
    $effects_menu = true
  end
end

# effects.rb ends here