scriptnode: add Value, MIDI CC, Tremolo and Test Tone preset scripts

scripts/dial.lua

@@ -0,0 +1,32 @@
+--- Value.
+--
+-- A single control output that emits a normalized value (0.0 - 1.0). The value
+-- is intended to be driven externally (host automation, MIDI mapping, etc.).
+--
+-- @script      value
+-- @type        DSP
+-- @license     GPL v3
+-- @author      Michael Fisher
+
+local function layout()
+    return {
+        audio   = { 0, 0 },
+        midi    = { 0, 0 },
+        control = { {}, {
+            { name = "Value", symbol = "value", min = 0.0, max = 1.0, default = 0.5 }
+        } }
+    }
+end
+
+local function process (_, _, _, _)
+    -- Output value is driven externally; nothing to compute here.
+end
+
+return {
+    type    = 'DSP',
+    layout  = layout,
+    process = process
+}
+
+-- SPDX-FileCopyrightText: Copyright (C) Kushview, LLC.
+-- SPDX-License-Identifier: GPL-3.0-or-later

scripts/midicc.lua

@@ -0,0 +1,66 @@
+--- MIDI CC.
+--
+-- Converts a normalized value (0.0 - 1.0) into a 0-127 MIDI Continuous Controller
+-- value. Emits a MIDI CC message on MIDI-out and exposes the scaled value as a
+-- control output. A message is only sent when the scaled value changes.
+--
+-- @script      midicc
+-- @type        DSP
+-- @license     GPL v3
+-- @author      Michael Fisher
+
+local MidiBuffer = require ('el.MidiBuffer')
+local midi       = require ('el.midi')
+local round      = require ('el.round')
+
+local output    = MidiBuffer.new()
+local lastValue = -1
+
+local function layout()
+    return {
+        audio   = { 0, 0 },
+        midi    = { 0, 1 },
+        control = { {
+            { name = "Value",   symbol = "value",   min = 0.0, max = 1.0, default = 0.0 },
+            { name = "CC",      symbol = "cc",      min = 0,   max = 127, default = 1 },
+            { name = "Channel", symbol = "channel", min = 1,   max = 16,  default = 1 }
+        }, {
+            { name = "Value", symbol = "value", min = 0, max = 127, default = 0 }
+        } }
+    }
+end
+
+local function prepare()
+    output:reserve (128)
+    output:clear()
+end
+
+local function process (_, m, p, c)
+    local out = m:get (1)
+    output:clear()
+
+    local value   = round.integer (p[1] * 127)
+    local cc      = round.integer (p[2])
+    local channel = round.integer (p[3])
+
+    -- Expose the scaled value as a control output.
+    c[1] = value
+
+    -- Only emit a message when the scaled value changes.
+    if value ~= lastValue then
+        output:insertPacked (midi.controller (channel, cc, value), 0)
+        lastValue = value
+    end
+
+    out:swap (output)
+end
+
+return {
+    type    = 'DSP',
+    layout  = layout,
+    prepare = prepare,
+    process = process
+}
+
+-- SPDX-FileCopyrightText: Copyright (C) Kushview, LLC.
+-- SPDX-License-Identifier: GPL-3.0-or-later

scripts/testtone.lua

@@ -0,0 +1,72 @@
+--- Test Tone.
+-- A simple sine wave generator, handy as a signal source for checking routing,
+-- levels and metering. Frequency is in Hz and Level scales the output amplitude.
+--
+-- @script      testtone
+-- @type        DSP
+-- @license     GPL v3
+-- @author      Michael Fisher
+
+-- Oscillator phase (radians) and current sample rate, kept across process blocks.
+local phase = 0.0
+local srate = 44100.0
+
+local function layout()
+    return {
+        audio   = { 0, 2 },
+        midi    = { 0, 0 },
+        control = {{
+            {
+                name    = "Frequency",
+                symbol  = "freq",
+                label   = "Hz",
+                min     = 20.0,
+                max     = 20000.0,
+                default = 440.0
+            },
+            {
+                name    = "Level",
+                symbol  = "level",
+                min     = 0.0,
+                max     = 1.0,
+                default = 0.5
+            }
+        }}
+    }
+end
+
+local function prepare (sampleRate, block)
+    srate = sampleRate
+    phase = 0.0
+end
+
+local function process (a, m, p)
+    local freq    = p[1]
+    local level   = p[2]
+    local nframes = a:length()
+    local nchans  = a:channels()
+    local inc     = (2.0 * math.pi * freq) / srate
+
+    for f = 1, nframes do
+        local s = level * math.sin (phase)
+
+        for c = 1, nchans do
+            a:set (c, f, s)
+        end
+
+        phase = phase + inc
+        if phase >= 2.0 * math.pi then
+            phase = phase - 2.0 * math.pi
+        end
+    end
+end
+
+return {
+    type    = 'DSP',
+    layout  = layout,
+    prepare = prepare,
+    process = process
+}
+
+-- SPDX-FileCopyrightText: Copyright (C) Kushview, LLC.
+-- SPDX-License-Identifier: GPL-3.0-or-later

scripts/tremolo.lua

@@ -0,0 +1,74 @@
+--- Tremolo.
+-- Amplitude modulation driven by a sine LFO. Rate sets the modulation speed in
+-- Hz and Depth controls how far the level drops at the trough of the wave.
+--
+-- @script      tremolo
+-- @type        DSP
+-- @license     GPL v3
+-- @author      Michael Fisher
+
+-- LFO phase (radians) and current sample rate, kept across process blocks.
+local phase = 0.0
+local srate = 44100.0
+
+local function layout()
+    return {
+        audio   = { 2, 2 },
+        midi    = { 0, 0 },
+        control = {{
+            {
+                name    = "Rate",
+                symbol  = "rate",
+                label   = "Hz",
+                min     = 0.1,
+                max     = 20.0,
+                default = 4.0
+            },
+            {
+                name    = "Depth",
+                symbol  = "depth",
+                min     = 0.0,
+                max     = 1.0,
+                default = 0.5
+            }
+        }}
+    }
+end
+
+local function prepare (sampleRate, block)
+    srate = sampleRate
+    phase = 0.0
+end
+
+local function process (a, m, p)
+    local freq    = p[1]
+    local depth   = p[2]
+    local nframes = a:length()
+    local nchans  = a:channels()
+    local inc     = (2.0 * math.pi * freq) / srate
+
+    for f = 1, nframes do
+        -- LFO ranges 0..1; gain ranges (1 - depth)..1
+        local lfo  = 0.5 + 0.5 * math.sin (phase)
+        local gain = 1.0 - depth * (1.0 - lfo)
+
+        for c = 1, nchans do
+            a:set (c, f, a:get (c, f) * gain)
+        end
+
+        phase = phase + inc
+        if phase >= 2.0 * math.pi then
+            phase = phase - 2.0 * math.pi
+        end
+    end
+end
+
+return {
+    type    = 'DSP',
+    layout  = layout,
+    prepare = prepare,
+    process = process
+}
+
+-- SPDX-FileCopyrightText: Copyright (C) Kushview, LLC.
+-- SPDX-License-Identifier: GPL-3.0-or-later

src/nodes/scriptnode.cpp

@@ -8,15 +8,11 @@
 
 #include "luascripts.hpp"
 
-#include "sol/sol.hpp"
-#include "element/element.h"
-#include "el/factories.hpp"
 #include "engine/graphnode.hpp"
 #include "nodes/scriptnode.hpp"
 #include "scripting/bindings.hpp"
 #include "scripting/dspscript.hpp"
 #include "scripting/scriptloader.hpp"
-#include "scripting/scriptmanager.hpp"
 
 #define EL_LUA_DBG(x)
 // #define EL_LUA_DBG(x) DBG(x)
@@ -260,6 +256,18 @@ const String ScriptNode::getProgramName (int index) const
         case 3:
             return "MIDI Timecode (MTC) Generator";
             break;
+        case 4:
+            return "Value";
+            break;
+        case 5:
+            return "MIDI CC";
+            break;
+        case 6:
+            return "Tremolo";
+            break;
+        case 7:
+            return "Test Tone";
+            break;
     }
 
     String name = TRANS ("Program");
@@ -292,6 +300,23 @@ void ScriptNode::setCurrentProgram (int index)
         case 3:
             newDspCode = String::fromUTF8 (scripts::mtc_generator_lua, scripts::mtc_generator_luaSize);
             newUiCode.clear();
+            break;
+        case 4:
+            newDspCode = String::fromUTF8 (scripts::dial_lua, scripts::dial_luaSize);
+            newUiCode.clear();
+            break;
+        case 5:
+            newDspCode = String::fromUTF8 (scripts::midicc_lua, scripts::midicc_luaSize);
+            newUiCode.clear();
+            break;
+        case 6:
+            newDspCode = String::fromUTF8 (scripts::tremolo_lua, scripts::tremolo_luaSize);
+            newUiCode.clear();
+            break;
+        case 7:
+            newDspCode = String::fromUTF8 (scripts::testtone_lua, scripts::testtone_luaSize);
+            newUiCode.clear();
+            break;
     }
 
     dspCode.replaceAllContent (newDspCode);

src/nodes/scriptnode.hpp

@@ -45,7 +45,7 @@ class ScriptNode : public Processor,
     void setPlayHead (juce::AudioPlayHead*) override;
 
     //==========================================================================
-    int getNumPrograms() const override { return 4; }
+    int getNumPrograms() const override { return 8; }
     int getCurrentProgram() const override { return _program; }
     const String getProgramName (int index) const override;
     void setCurrentProgram (int index) override;

test/CMakeLists.txt

@@ -41,6 +41,7 @@ add_test(NAME "NodeTests" COMMAND test_element --run_test=NodeTests)
 add_test(NAME "OversamplerTests" COMMAND test_element --run_test=OversamplerTests)
 add_test(NAME "PluginManagerTests" COMMAND test_element --run_test=PluginManagerTests)
 add_test(NAME "PortListTests" COMMAND test_element --run_test=PortListTests)
+add_test(NAME "PresetScriptsTest" COMMAND test_element --run_test=PresetScriptsTest)
 add_test(NAME "PortTypeTests" COMMAND test_element --run_test=PortTypeTests)
 add_test(NAME "RootGraphTests" COMMAND test_element --run_test=RootGraphTests)
 add_test(NAME "ScriptInfoTest" COMMAND test_element --run_test=ScriptInfoTest)