Add LuaJITEngine

Makefile

@@ -16,6 +16,7 @@ include $(RACK_DIR)/arch.mk
 DUKTAPE ?= 0
 QUICKJS ?= 1
 PYTHON ?= 1
+LUA ?= 1
 
 # Entropia File System Watcher
 efsw := dep/lib/libefsw-static-release.a
@@ -97,14 +98,19 @@ $(numpy): $(python)
 # 	cd dep/scipy-1.3.1 && "$(DEP_PATH)"/bin/python3.7 setup.py build -j4 install
 endif
 
-# # LuaJIT
-# luajit := dep/lib/luajit.a
-# DEPS += $(luajit)
-# $(luajit):
-# 	cd dep && $(WGET) "http://luajit.org/download/LuaJIT-2.0.5.tar.gz"
-# 	cd dep && $(SHA256) LuaJIT-2.0.5.tar.gz 874b1f8297c697821f561f9b73b57ffd419ed8f4278c82e05b48806d30c1e979
-# 	cd dep && $(UNTAR) LuaJIT-2.0.5.tar.gz
-# 	cd dep/LuaJIT-2.0.5 && $(MAKE)
+# LuaJIT
+ifeq ($(LUA), 1)
+SOURCES += src/LuaJITEngine.cpp
+luajit := dep/lib/libluajit-5.1.a
+OBJECTS += $(luajit)
+DEPS += $(luajit)
+$(luajit):
+	$(WGET) "http://luajit.org/download/LuaJIT-2.0.5.tar.gz"
+	$(SHA256) LuaJIT-2.0.5.tar.gz 874b1f8297c697821f561f9b73b57ffd419ed8f4278c82e05b48806d30c1e979
+	cd dep && $(UNTAR) ../LuaJIT-2.0.5.tar.gz
+	cd dep/LuaJIT-2.0.5 && $(MAKE)
+	cd dep/LuaJIT-2.0.5 && $(MAKE) PREFIX="$(DEP_PATH)" install
+endif
 
 # # Julia
 # julia := dep/lib/libjulia.a

README.md

@@ -124,6 +124,6 @@ sudo pacman -S premake
 ## Contributors
 
 - [Wes Milholen](https://grayscale.info/): panel design
-- [Andrew Belt](https://github.com/AndrewBelt): host code, Duktape (JavaScript)
+- [Andrew Belt](https://github.com/AndrewBelt): host code, Duktape (JavaScript), LuaJIT (in development), Python (in development)
 - [Jerry Sievert](https://github.com/JerrySievert): QuickJS (JavaScript)
 - add your name here

examples/gain.js

@@ -3,13 +3,13 @@
 
 function process(block) {
 	// Loop through each column
-	for (var i = 0; i < 6; i++) {
+	for (let i = 0; i < 6; i++) {
 		// Get input
-		var x = block.inputs[i][0]
+		let x = block.inputs[i][0]
 		// Get gain knob
-		var gain = block.knobs[i]
+		let gain = block.knobs[i]
 		// Apply gain to input
-		var y = x * gain
+		let y = x * gain
 		// Set gain light (red = 0)
 		block.lights[i][0] = gain
 		// Check mute switch

examples/gain.lua

@@ -0,0 +1,28 @@
+-- Simplest possible script using all variables
+-- by Andrew Belt
+
+function process(block)
+	-- Loop through each column
+	for i=1,6 do
+		-- Get input
+		x = block.inputs[i][1]
+		-- Get gain knob
+		gain = block.knobs[i]
+		-- Apply gain to input
+		y = x * gain
+		-- Set gain light (red = 0)
+		block.lights[i][1] = gain
+		-- Check mute switch
+		if block.switches[i] then
+			-- Mute output
+			y = 0
+			-- Enable mute light (red = 0)
+			block.switchLights[i][1] = 1
+		else
+			-- Disable mute light
+			block.switchLights[i][1] = 0
+		end
+		-- Set output
+		block.outputs[i][1] = y
+	end
+end

examples/rainbow.lua

@@ -0,0 +1,44 @@
+-- Rainbow RGB LED example
+-- by Andrew Belt
+
+-- Call process() every 256 audio samples
+config.frameDivider = 256
+
+
+-- From https://en.wikipedia.org/wiki/HSL_and_HSV#HSV_to_RGB
+function hsvToRgb(h, s, v)
+	h = h * 6
+	c = v * s
+	x = c * (1 - math.abs(h % 2 - 1))
+	if (h < 1) then rgb = {c, x, 0}
+	elseif (h < 2) then rgb = {x, c, 0}
+	elseif (h < 3) then rgb = {0, c, x}
+	elseif (h < 4) then rgb = {0, x, c}
+	elseif (h < 5) then rgb = {x, 0, c}
+	else rgb = {c, 0, x}
+	end
+	m = v - c
+	rgb[1] = rgb[1] + m
+	rgb[2] = rgb[2] + m
+	rgb[3] = rgb[3] + m
+	return rgb
+end
+
+
+phase = 0
+function process(block)
+	phase = phase + block.sampleTime * config.frameDivider * 0.5
+	phase = phase % 1
+
+	for i=1,6 do
+		h = (1 - i / 6 + phase) % 1
+		rgb = hsvToRgb(h, 1, 1)
+		for c=1,3 do
+			block.lights[i][c] = rgb[c]
+			block.switchLights[i][c] = rgb[c]
+		end
+		block.outputs[i][1] = math.sin(2 * math.pi * h) * 5 + 5
+	end
+end
+
+display("Hello, world!")

src/DuktapeEngine.cpp

@@ -16,17 +16,19 @@ struct DuktapeEngine : ScriptEngine {
 
 	int run(const std::string& path, const std::string& script) override {
 		assert(!ctx);
+		ProcessBlock* block = getProcessBlock();
+
 		// Create duktape context
 		ctx = duk_create_heap_default();
 		if (!ctx) {
-			setMessage("Could not create duktape context");
+			display("Could not create duktape context");
 			return -1;
 		}
 
 		// Initialize globals
 		// user pointer
 		duk_push_pointer(ctx, this);
-		duk_put_global_string(ctx, DUK_HIDDEN_SYMBOL("p"));
+		duk_put_global_string(ctx, DUK_HIDDEN_SYMBOL("engine"));
 
 		// console
 		duk_idx_t consoleIdx = duk_push_object(ctx);
@@ -34,15 +36,6 @@ struct DuktapeEngine : ScriptEngine {
 			// log
 			duk_push_c_function(ctx, native_console_log, 1);
 			duk_put_prop_string(ctx, consoleIdx, "log");
-			// info (alias for log)
-			duk_push_c_function(ctx, native_console_log, 1);
-			duk_put_prop_string(ctx, consoleIdx, "info");
-			// debug
-			duk_push_c_function(ctx, native_console_debug, 1);
-			duk_put_prop_string(ctx, consoleIdx, "debug");
-			// warn
-			duk_push_c_function(ctx, native_console_warn, 1);
-			duk_put_prop_string(ctx, consoleIdx, "warn");
 		}
 		duk_put_global_string(ctx, "console");
 
@@ -67,7 +60,7 @@ struct DuktapeEngine : ScriptEngine {
 		if (duk_pcompile_lstring_filename(ctx, 0, script.c_str(), script.size()) != 0) {
 			const char* s = duk_safe_to_string(ctx, -1);
 			WARN("duktape: %s", s);
-			setMessage(s);
+			display(s);
 			duk_pop(ctx);
 			return -1;
 		}
@@ -75,7 +68,7 @@ struct DuktapeEngine : ScriptEngine {
 		if (duk_pcall(ctx, 0)) {
 			const char* s = duk_safe_to_string(ctx, -1);
 			WARN("duktape: %s", s);
-			setMessage(s);
+			display(s);
 			duk_pop(ctx);
 			return -1;
 		}
@@ -91,7 +84,7 @@ struct DuktapeEngine : ScriptEngine {
 			duk_pop(ctx);
 			// bufferSize
 			duk_get_prop_string(ctx, -1, "bufferSize");
-			block->bufferSize = duk_get_int(ctx, -1);
+			setBufferSize(duk_get_int(ctx, -1));
 			duk_pop(ctx);
 		}
 		duk_pop(ctx);
@@ -99,7 +92,7 @@ struct DuktapeEngine : ScriptEngine {
 		// Keep process function on stack for faster calling
 		duk_get_global_string(ctx, "process");
 		if (!duk_is_function(ctx, -1)) {
-			setMessage("No process() function");
+			display("No process() function");
 			return -1;
 		}
 
@@ -170,6 +163,7 @@ struct DuktapeEngine : ScriptEngine {
 
 	int process() override {
 		// block
+		ProcessBlock* block = getProcessBlock();
 		duk_idx_t blockIdx = duk_get_top(ctx) - 1;
 		{
 			// sampleRate
@@ -193,7 +187,7 @@ struct DuktapeEngine : ScriptEngine {
 		if (duk_pcall(ctx, 1)) {
 			const char* s = duk_safe_to_string(ctx, -1);
 			WARN("duktape: %s", s);
-			setMessage(s);
+			display(s);
 			duk_pop(ctx);
 			return -1;
 		}
@@ -204,7 +198,7 @@ struct DuktapeEngine : ScriptEngine {
 	}
 
 	static DuktapeEngine* getDuktapeEngine(duk_context* ctx) {
-		duk_get_global_string(ctx, DUK_HIDDEN_SYMBOL("p"));
+		duk_get_global_string(ctx, DUK_HIDDEN_SYMBOL("engine"));
 		DuktapeEngine* engine = (DuktapeEngine*) duk_get_pointer(ctx, -1);
 		duk_pop(ctx);
 		return engine;
@@ -212,22 +206,12 @@ struct DuktapeEngine : ScriptEngine {
 
 	static duk_ret_t native_console_log(duk_context* ctx) {
 		const char* s = duk_safe_to_string(ctx, -1);
-		INFO("VCV Prototype: %s", s);
-		return 0;
-	}
-	static duk_ret_t native_console_debug(duk_context* ctx) {
-		const char* s = duk_safe_to_string(ctx, -1);
-		DEBUG("VCV Prototype: %s", s);
-		return 0;
-	}
-	static duk_ret_t native_console_warn(duk_context* ctx) {
-		const char* s = duk_safe_to_string(ctx, -1);
-		WARN("VCV Prototype: %s", s);
+		INFO("Duktape: %s", s);
 		return 0;
 	}
 	static duk_ret_t native_display(duk_context* ctx) {
 		const char* s = duk_safe_to_string(ctx, -1);
-		getDuktapeEngine(ctx)->setMessage(s);
+		getDuktapeEngine(ctx)->display(s);
 		return 0;
 	}
 };

src/LuaJITEngine.cpp

@@ -0,0 +1,300 @@
+#include "ScriptEngine.hpp"
+#include <luajit-2.0/lua.hpp>
+
+
+struct LuaJITEngine : ScriptEngine {
+	lua_State* L = NULL;
+
+	~LuaJITEngine() {
+		if (L)
+			lua_close(L);
+	}
+
+	std::string getEngineName() override {
+		return "Lua";
+	}
+
+	int run(const std::string& path, const std::string& script) override {
+		ProcessBlock* block = getProcessBlock();
+
+		L = luaL_newstate();
+		if (!L) {
+			display("Could not create LuaJIT context");
+			return -1;
+		}
+
+		// Import a subset of the standard library
+		luaopen_base(L);
+		luaopen_string(L);
+		luaopen_table(L);
+		luaopen_math(L);
+
+		// Set user pointer
+		lua_pushlightuserdata(L, this);
+		lua_setglobal(L, "_engine");
+
+		// Set global functions
+		lua_pushcfunction(L, native_print);
+		lua_setglobal(L, "print");
+
+		lua_pushcfunction(L, native_display);
+		lua_setglobal(L, "display");
+
+		// Set config
+		lua_newtable(L);
+		{
+			// frameDivider
+			lua_pushinteger(L, 32);
+			lua_setfield(L, -2, "frameDivider");
+			// bufferSize
+			lua_pushinteger(L, 1);
+			lua_setfield(L, -2, "bufferSize");
+		}
+		lua_setglobal(L, "config");
+
+		// Compile script
+		if (luaL_loadbuffer(L, script.c_str(), script.size(), path.c_str())) {
+			const char* s = lua_tostring(L, -1);
+			WARN("LuaJIT: %s", s);
+			display(s);
+			lua_pop(L, 1);
+			return -1;
+		}
+
+		// Run script
+		if (lua_pcall(L, 0, 0, 0)) {
+			const char* s = lua_tostring(L, -1);
+			WARN("LuaJIT: %s", s);
+			display(s);
+			lua_pop(L, 1);
+			return -1;
+		}
+
+		// Get config
+		lua_getglobal(L, "config");
+		{
+			// frameDivider
+			lua_getfield(L, -1, "frameDivider");
+			int frameDivider = lua_tointeger(L, -1);
+			setFrameDivider(frameDivider);
+			lua_pop(L, 1);
+			// bufferSize
+			lua_getfield(L, -1, "bufferSize");
+			int bufferSize = lua_tointeger(L, -1);
+			setBufferSize(bufferSize);
+			lua_pop(L, 1);
+		}
+		lua_pop(L, 1);
+
+		// Get process function
+		lua_getglobal(L, "process");
+		if (!lua_isfunction(L, -1)) {
+			display("No process() function");
+			return -1;
+		}
+
+		// Create block object
+		lua_newtable(L);
+		{
+			// inputs
+			lua_newtable(L);
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_newtable(L);
+				for (int j = 0; j < block->bufferSize; j++) {
+					lua_pushnumber(L, 0.0);
+					lua_rawseti(L, -2, j + 1);
+				}
+				lua_rawseti(L, -2, i + 1);
+			}
+			lua_setfield(L, -2, "inputs");
+			// outputs
+			lua_newtable(L);
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_newtable(L);
+				for (int j = 0; j < block->bufferSize; j++) {
+					lua_pushnumber(L, 0.0);
+					lua_rawseti(L, -2, j + 1);
+				}
+				lua_rawseti(L, -2, i + 1);
+			}
+			lua_setfield(L, -2, "outputs");
+			// knobs
+			lua_newtable(L);
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_pushnumber(L, 0.0);
+				lua_rawseti(L, -2, i + 1);
+			}
+			lua_setfield(L, -2, "knobs");
+			// switches
+			lua_newtable(L);
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_pushboolean(L, false);
+				lua_rawseti(L, -2, i + 1);
+			}
+			lua_setfield(L, -2, "switches");
+			// lights
+			lua_newtable(L);
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_newtable(L);
+				for (int c = 0; c < 3; c++) {
+					lua_pushnumber(L, 0.0);
+					lua_rawseti(L, -2, c + 1);
+				}
+				lua_rawseti(L, -2, i + 1);
+			}
+			lua_setfield(L, -2, "lights");
+			// switchLights
+			lua_newtable(L);
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_newtable(L);
+				for (int c = 0; c < 3; c++) {
+					lua_pushnumber(L, 0.0);
+					lua_rawseti(L, -2, c + 1);
+				}
+				lua_rawseti(L, -2, i + 1);
+			}
+			lua_setfield(L, -2, "switchLights");
+		}
+
+		return 0;
+	}
+
+	int process() override {
+		ProcessBlock* block = getProcessBlock();
+
+		// Set block
+		{
+			// sampleRate
+			lua_pushnumber(L, block->sampleRate);
+			lua_setfield(L, -2, "sampleRate");
+
+			// sampleTime
+			lua_pushnumber(L, block->sampleTime);
+			lua_setfield(L, -2, "sampleTime");
+
+			// bufferSize
+			lua_pushinteger(L, block->bufferSize);
+			lua_setfield(L, -2, "bufferSize");
+
+			// inputs
+			lua_getfield(L, -1, "inputs");
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_rawgeti(L, -1, i + 1);
+				for (int j = 0; j < block->bufferSize; j++) {
+					lua_pushnumber(L, block->inputs[i][j]);
+					lua_rawseti(L, -2, j + 1);
+				}
+				lua_pop(L, 1);
+			}
+			lua_pop(L, 1);
+			// knobs
+			lua_getfield(L, -1, "knobs");
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_pushnumber(L, block->knobs[i]);
+				lua_rawseti(L, -2, i + 1);
+			}
+			lua_pop(L, 1);
+			// switches
+			lua_getfield(L, -1, "switches");
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_pushboolean(L, block->switches[i]);
+				lua_rawseti(L, -2, i + 1);
+			}
+			lua_pop(L, 1);
+		}
+
+		// Duplicate process function
+		lua_pushvalue(L, -2);
+		// Duplicate block
+		lua_pushvalue(L, -2);
+		// Call process function
+		if (lua_pcall(L, 1, 0, 0)) {
+			const char* err = lua_tostring(L, -1);
+			WARN("LuaJIT: %s", err);
+			display(err);
+			return -1;
+		}
+
+		// Get block
+		{
+			// outputs
+			lua_getfield(L, -1, "outputs");
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_rawgeti(L, -1, i + 1);
+				for (int j = 0; j < block->bufferSize; j++) {
+					lua_rawgeti(L, -1, j + 1);
+					block->outputs[i][j] = lua_tonumber(L, -1);
+					lua_pop(L, 1);
+				}
+				lua_pop(L, 1);
+			}
+			lua_pop(L, 1);
+			// knobs
+			lua_getfield(L, -1, "knobs");
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_rawgeti(L, -1, i + 1);
+				block->knobs[i] = lua_tonumber(L, -1);
+				lua_pop(L, 1);
+			}
+			lua_pop(L, 1);
+			// lights
+			lua_getfield(L, -1, "lights");
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_rawgeti(L, -1, i + 1);
+				for (int c = 0; c < 3; c++) {
+					lua_rawgeti(L, -1, c + 1);
+					block->lights[i][c] = lua_tonumber(L, -1);
+					lua_pop(L, 1);
+				}
+				lua_pop(L, 1);
+			}
+			lua_pop(L, 1);
+			// switchLights
+			lua_getfield(L, -1, "switchLights");
+			for (int i = 0; i < NUM_ROWS; i++) {
+				lua_rawgeti(L, -1, i + 1);
+				for (int c = 0; c < 3; c++) {
+					lua_rawgeti(L, -1, c + 1);
+					block->switchLights[i][c] = lua_tonumber(L, -1);
+					lua_pop(L, 1);
+				}
+				lua_pop(L, 1);
+			}
+			lua_pop(L, 1);
+		}
+
+		return 0;
+	}
+
+	static LuaJITEngine* getEngine(lua_State* L) {
+		lua_getglobal(L, "_engine");
+		LuaJITEngine* engine = (LuaJITEngine*) lua_touserdata(L, -1);
+		lua_pop(L, 1);
+		return engine;
+	}
+
+	static int native_print(lua_State* L) {
+		lua_getglobal(L, "tostring");
+		lua_pushvalue(L, 1);
+		lua_call(L, 1, 1);
+		const char* s = lua_tostring(L, 1);
+		INFO("LuaJIT: %s", s);
+		return 0;
+	}
+
+	static int native_display(lua_State* L) {
+		lua_getglobal(L, "tostring");
+		lua_pushvalue(L, 1);
+		lua_call(L, 1, 1);
+		const char* s = lua_tostring(L, -1);
+		if (!s)
+			s = "(null)";
+		getEngine(L)->display(s);
+		return 0;
+	}
+};
+
+
+ScriptEngine* createLuaJITEngine() {
+	return new LuaJITEngine;
+}

src/Prototype.cpp

@@ -41,7 +41,7 @@ struct Prototype : Module {
 	ScriptEngine* scriptEngine = NULL;
 	int frame = 0;
 	int frameDivider;
-	ScriptEngine::ProcessBlock* block;
+	ProcessBlock* block;
 	int bufferIndex = 0;
 
 	efsw_watcher efsw = NULL;
@@ -53,7 +53,7 @@ struct Prototype : Module {
 		for (int i = 0; i < NUM_ROWS; i++)
 			configParam(SWITCH_PARAMS + i, 0.f, 1.f, 0.f, string::f("Switch %d", i + 1));
 
-		block = new ScriptEngine::ProcessBlock;
+		block = new ProcessBlock;
 		setPath("");
 	}
 
@@ -179,7 +179,7 @@ struct Prototype : Module {
 		// Reset process state
 		frameDivider = 32;
 		frame = 0;
-		*block = ScriptEngine::ProcessBlock();
+		*block = ProcessBlock();
 		bufferIndex = 0;
 		// Reset outputs and lights because they might hold old values
 		for (int i = 0; i < NUM_ROWS; i++)
@@ -203,7 +203,6 @@ struct Prototype : Module {
 			return;
 		}
 		scriptEngine->module = this;
-		scriptEngine->block = block;
 
 		// Run script
 		if (scriptEngine->run(path, script)) {
@@ -212,7 +211,6 @@ struct Prototype : Module {
 			scriptEngine = NULL;
 			return;
 		}
-		block->bufferSize = clamp(block->bufferSize, 1, MAX_BUFFER_SIZE);
 		this->engineName = scriptEngine->getEngineName();
 	}
 
@@ -296,12 +294,19 @@ struct Prototype : Module {
 };
 
 
-void ScriptEngine::setMessage(const std::string& message) {
+void ScriptEngine::display(const std::string& message) {
 	module->message = message;
 }
 void ScriptEngine::setFrameDivider(int frameDivider) {
 	module->frameDivider = frameDivider;
 }
+void ScriptEngine::setBufferSize(int bufferSize) {
+	bufferSize = clamp(bufferSize, 1, MAX_BUFFER_SIZE);
+	module->block->bufferSize = bufferSize;
+}
+ProcessBlock* ScriptEngine::getProcessBlock() {
+	return module->block;
+}
 
 
 struct FileChoice : LedDisplayChoice {

src/PythonEngine.cpp

@@ -103,6 +103,7 @@ struct PythonEngine : ScriptEngine {
 		DEFER({Py_DECREF(result);});
 
 		// Create block
+		ProcessBlock* block = getProcessBlock();
 		static PyStructSequence_Field blockFields[] = {
 			{"inputs", ""},
 			{"outputs", ""},
@@ -154,11 +155,11 @@ struct PythonEngine : ScriptEngine {
 		// Get process function from globals
 		processFunc = PyDict_GetItemString(mainDict, "process");
 		if (!processFunc) {
-			setMessage("No process() function");
+			display("No process() function");
 			return -1;
 		}
 		if (!PyCallable_Check(processFunc)) {
-			setMessage("process() is not callable");
+			display("process() is not callable");
 			return -1;
 		}
 
@@ -181,7 +182,7 @@ struct PythonEngine : ScriptEngine {
 			// if (!str)
 			// 	return -1;
 
-			// setMessage(str);
+			// display(str);
 			return -1;
 		}
 		DEFER({Py_DECREF(processResult);});
@@ -209,7 +210,7 @@ struct PythonEngine : ScriptEngine {
 		DEFER({Py_DECREF(msgS);});
 
 		const char* msg = PyUnicode_AsUTF8(msgS);
-		that->setMessage(msg);
+		that->display(msg);
 
 		Py_INCREF(Py_None);
 		return Py_None;

src/QuickJSEngine.cpp

@@ -65,7 +65,7 @@ struct QuickJSEngine : ScriptEngine {
 		// Create quickjs context
 		ctx = JS_NewContext(rt);
 		if (!ctx) {
-			setMessage("Could not create QuickJS context");
+			display("Could not create QuickJS context");
 			return -1;
 		}
 
@@ -107,13 +107,14 @@ struct QuickJSEngine : ScriptEngine {
 		// Compile string
     JSValue val = JS_Eval(ctx, script.c_str(), script.size(), path.c_str(), 0);
     if (JS_IsException(val)) {
-      setMessage(ErrorToString(ctx));
+      display(ErrorToString(ctx));
       JS_FreeValue(ctx, val);
       JS_FreeValue(ctx, global_obj);
 
       return -1;
     }
 
+    ProcessBlock* block = getProcessBlock();
     // config: Read values
     config = JS_GetPropertyStr(ctx, global_obj, "config");
     {
@@ -128,7 +129,7 @@ struct QuickJSEngine : ScriptEngine {
       JSValue buffer = JS_GetPropertyStr(ctx, config, "bufferSize");
       int32_t bufferValue;
       if (JS_ToInt32(ctx, &bufferValue, buffer) == 0) {
-        block->bufferSize = bufferValue;
+        setBufferSize(bufferValue);
       }
 
       JS_FreeValue(ctx, config);
@@ -204,7 +205,7 @@ struct QuickJSEngine : ScriptEngine {
     if (JS_IsException(hack)) {
       std::string errorString = ErrorToString(ctx);
       WARN("QuickJS: %s", errorString.c_str());
-      setMessage(errorString.c_str());
+      display(errorString.c_str());
     }
 
     JS_FreeValue(ctx, hack);
@@ -215,7 +216,7 @@ struct QuickJSEngine : ScriptEngine {
     if (JS_IsException(val)) {
       std::string errorString = ErrorToString(ctx);
       WARN("QuickJS: %s", errorString.c_str());
-      setMessage(errorString.c_str());
+      display(errorString.c_str());
 
       JS_FreeValue(ctx, val);
       JS_FreeValue(ctx, blockIdx);
@@ -232,6 +233,7 @@ struct QuickJSEngine : ScriptEngine {
     JSValue global_obj = JS_GetGlobalObject(ctx);
 
     // block
+    ProcessBlock* block = getProcessBlock();
     JSValue blockIdx = JS_GetPropertyStr(ctx, global_obj, "block");
     {
       // sampleRate
@@ -254,7 +256,7 @@ struct QuickJSEngine : ScriptEngine {
     if (JS_IsException(val)) {
       std::string errorString = ErrorToString(ctx);
       WARN("QuickJS: %s", errorString.c_str());
-      setMessage(errorString.c_str());
+      display(errorString.c_str());
 
       JS_FreeValue(ctx, val);
       JS_FreeValue(ctx, process);
@@ -286,7 +288,7 @@ struct QuickJSEngine : ScriptEngine {
                                     int argc, JSValueConst *argv) {
     if (argc) {
       const char *s = JS_ToCString(ctx, argv[0]);
-      INFO("VCV Prototype: %s", s);
+      INFO("QuickJS: %s", s);
     }
 		return JS_UNDEFINED;
 	}
@@ -294,7 +296,7 @@ struct QuickJSEngine : ScriptEngine {
                                     int argc, JSValueConst *argv) {
     if (argc) {
       const char *s = JS_ToCString(ctx, argv[0]);
-      DEBUG("VCV Prototype: %s", s);
+      DEBUG("QuickJS: %s", s);
     }
 		return JS_UNDEFINED;
 	}
@@ -302,7 +304,7 @@ struct QuickJSEngine : ScriptEngine {
                                     int argc, JSValueConst *argv) {
     if (argc) {
       const char *s = JS_ToCString(ctx, argv[0]);
-      INFO("VCV Prototype: %s", s);
+      INFO("QuickJS: %s", s);
     }
 		return JS_UNDEFINED;
 	}
@@ -310,7 +312,7 @@ struct QuickJSEngine : ScriptEngine {
                                     int argc, JSValueConst *argv) {
     if (argc) {
       const char *s = JS_ToCString(ctx, argv[0]);
-      WARN("VCV Prototype: %s", s);
+      WARN("QuickJS: %s", s);
     }
 		return JS_UNDEFINED;
 	}
@@ -318,7 +320,7 @@ struct QuickJSEngine : ScriptEngine {
                                     int argc, JSValueConst *argv) {
     if (argc) {
       const char *s = JS_ToCString(ctx, argv[0]);
-  		getQuickJSEngine(ctx)->setMessage(s);
+  		getQuickJSEngine(ctx)->display(s);
     }
 		return JS_UNDEFINED;
 	}

src/ScriptEngine.hpp

@@ -9,21 +9,20 @@ static const int MAX_BUFFER_SIZE = 4096;
 struct Prototype;
 
 
-struct ScriptEngine {
-	struct ProcessBlock {
-		float sampleRate = 0.f;
-		float sampleTime = 0.f;
-		int bufferSize = 1;
-		float inputs[NUM_ROWS][MAX_BUFFER_SIZE] = {};
-		float outputs[NUM_ROWS][MAX_BUFFER_SIZE] = {};
-		float knobs[NUM_ROWS] = {};
-		bool switches[NUM_ROWS] = {};
-		float lights[NUM_ROWS][3] = {};
-		float switchLights[NUM_ROWS][3] = {};
-	};
-	/** Set by module */
-	ProcessBlock* block = NULL;
+struct ProcessBlock {
+	float sampleRate = 0.f;
+	float sampleTime = 0.f;
+	int bufferSize = 1;
+	float inputs[NUM_ROWS][MAX_BUFFER_SIZE] = {};
+	float outputs[NUM_ROWS][MAX_BUFFER_SIZE] = {};
+	float knobs[NUM_ROWS] = {};
+	bool switches[NUM_ROWS] = {};
+	float lights[NUM_ROWS][3] = {};
+	float switchLights[NUM_ROWS][3] = {};
+};
 
+
+struct ScriptEngine {
 	// Virtual methods for subclasses
 	virtual ~ScriptEngine() {}
 	virtual std::string getEngineName() {return "";}
@@ -40,8 +39,10 @@ struct ScriptEngine {
 
 	// Communication with Prototype module.
 	// These cannot be called from your constructor, so initialize your engine in the run() method.
-	void setMessage(const std::string& message);
+	void display(const std::string& message);
 	void setFrameDivider(int frameDivider);
+	void setBufferSize(int bufferSize);
+	ProcessBlock* getProcessBlock();
 	// private
 	Prototype* module = NULL;
 };
@@ -53,11 +54,14 @@ struct ScriptEngine {
 ScriptEngine* createDuktapeEngine();
 ScriptEngine* createQuickJSEngine();
 ScriptEngine* createPythonEngine();
+ScriptEngine* createLuaJITEngine();
 
 inline ScriptEngine* createScriptEngine(std::string ext) {
 	ext = rack::string::lowercase(ext);
 	if (ext == "js")
 		return createQuickJSEngine();
+	else if (ext == "lua")
+		return createLuaJITEngine();
 	else if (ext == "py")
 		return createPythonEngine();
 	// Add your file extension check here.

tests/hello.lua

@@ -0,0 +1,11 @@
+
+config.frameDivider = 1
+config.bufferSize = 16
+
+function process(block)
+	for j=1,block.bufferSize do
+		block.outputs[1][j] = math.random()
+	end
+end
+
+print("Hello, world!")