update lua scripts

* add proper amplifier (smooth gain change) + text-example
* remove commented no-inplace from High/Low pass
* amend 913609be inline spectrogam re-init

diff --git a/scripts/amp4.lua b/scripts/amp4.lua
new file mode 100644 (file)
index 0000000..a348d16
--- /dev/null
+++ b/scripts/amp4.lua
@@ -0,0 +1,118 @@
+ardour {
+       ["type"]    = "dsp",
+       name        = "Amplifier",
+       category    = "Amplifier",
+       license     = "MIT",
+       author      = "Robin Gareus",
+       email       = "robin@gareus.org",
+       site        = "http://gareus.org",
+       description = [[ Versatile +/- 20dB multichannel amplifier]]
+}
+
+function dsp_ioconfig ()
+       return
+       {
+               { audio_in = -1, audio_out = -1},
+       }
+end
+
+
+function dsp_params ()
+       return
+       {
+               { ["type"] = "input", name = "Gain", min = -20, max = 20, default = 0, unit="dB"},
+       }
+end
+
+local lpf = 0.02 -- parameter low-pass filter time-constant
+local cur_gain = 0 -- current gain (dB)
+
+-- called once when plugin is instantiated
+function dsp_init (rate)
+       lpf = 780 / rate -- interpolation time constant
+end
+
+function low_pass_filter_param (old, new, limit)
+       if math.abs (old - new) < limit  then
+               return new
+       else
+               return old + lpf * (new - old)
+       end
+end
+
+-- use ardour's vectorized functions
+--
+-- This is as efficient as Ardour doing it itself in C++
+-- Lua function overhead is negligible
+--
+-- this also exemplifies the /simpler/ way of delegating the
+-- channel-mapping to ardour.
+
+function dsp_run (ins, outs, n_samples)
+       assert (#ins == #outs) -- ensure that we can run in-place (channel count matches)
+       local ctrl = CtrlPorts:array() -- get control port array (read/write)
+       local siz = n_samples
+       local off = 0
+       local changed = false
+
+       -- if the gain parameter was changed, process at most 64 samples at a time
+       -- and interpolate gain until the current settings match the target values
+       if cur_gain ~= ctrl[1] then
+               changed = true
+               siz = 32
+       end
+
+       while n_samples > 0 do
+               if siz > n_samples then siz = n_samples end
+               if changed then
+                       cur_gain = low_pass_filter_param (cur_gain, ctrl[1], 0.05)
+               end
+
+               local gain = ARDOUR.DSP.dB_to_coefficient (cur_gain) -- 10 ^ (0.05 * cur_gain)
+               for c = 1,#ins do -- process all channels
+                       -- check if output and input buffers for this channel are identical
+                       -- http://manual.ardour.org/lua-scripting/class_reference/#C:FloatArray
+                       if not ins[c]:sameinstance (outs[c]) then
+                               -- http://manual.ardour.org/lua-scripting/class_reference/#ARDOUR:DSP
+                               ARDOUR.DSP.copy_vector (outs[c]:offset (off), ins[c]:offset (off), siz)
+                       end
+                       ARDOUR.DSP.apply_gain_to_buffer (outs[c]:offset (off), siz, gain); -- process in-place
+               end
+               n_samples = n_samples - siz
+               off = off + siz
+       end
+
+       if changed then
+               self:queue_draw () -- notify display
+       end
+end
+
+-------------------------------------------------------------------------------
+--- inline display + text example
+
+local txt = nil -- cache globally
+function render_inline (ctx, w, max_h)
+       local ctrl = CtrlPorts:array ()
+
+       if not txt then
+               txt = Cairo.PangoLayout (ctx, "Mono 8px")
+       end
+
+       txt:set_text (string.format ("%+.2f dB", ctrl[1]));
+       tw, th = txt:get_pixel_size ()
+
+       local h = math.ceil (th + 4) -- use text-height with 4px padding
+       if (h > max_h) then h = max_h end -- but at most max-height
+
+       -- clear background
+       ctx:rectangle (0, 0, w, h)
+       ctx:set_source_rgba (.2, .2, .2, 1.0)
+       ctx:fill ()
+
+       -- center text
+       ctx:set_source_rgba (.8, .8, .8, 1.0)
+       ctx:move_to ( .5 * (w - tw), .5 * (h - th))
+       txt:show_in_cairo_context (ctx)
+
+       return {w, h}
+end

diff --git a/scripts/hplp.lua b/scripts/hplp.lua
index 3a1b7b981db53f4099bf96b8a0782c2ccacb8040..40cd22254efffefcae31ba2dacf5f1512b8e4481 100644 (file)
--- a/scripts/hplp.lua
+++ b/scripts/hplp.lua
@@ -150,16 +150,12 @@ function dsp_run (ins, outs, n_samples)
                for c = 1,#ins do
                        -- check if output and input buffers for this channel are identical
                        -- http://manual.ardour.org/lua-scripting/class_reference/#C:FloatArray
-                       if false then --- ins[c]:sameinstance (outs[c]) then
-                               for k = 1,o do
-                                       filters[c][k]:run (ins[c]:offset (off), siz) -- in-place processing
-                               end
-                       else
+                       if not ins[c]:sameinstance (outs[c]) then
                                -- http://manual.ardour.org/lua-scripting/class_reference/#ARDOUR:DSP
                                ARDOUR.DSP.copy_vector (outs[c]:offset (off), ins[c]:offset (off), siz)
-                               for k = 1,o do
-                                       filters[c][k]:run (outs[c]:offset (off), siz)
-                               end
+                       end
+                       for k = 1,o do
+                               filters[c][k]:run (outs[c]:offset (off), siz) -- in-place processing
                        end
                end
 

diff --git a/scripts/spectrogram.lua b/scripts/spectrogram.lua
index f82d4fe4bb2f34bc1f0e4ecf6536ec9756ef9399..980a308f959d0296aee2387fd3a59578096e1e15 100644 (file)
--- a/scripts/spectrogram.lua
+++ b/scripts/spectrogram.lua
@@ -215,6 +215,7 @@ function render_inline (ctx, w, max_h)
        -- re-create image surface
        if not img or img:get_width() ~= w or img:get_height () ~= h then
                img = Cairo.ImageSurface (Cairo.Format.ARGB32, w, h)
+               line = 0
        end
        local ictx = img:context ()