re-added MultiScript

The very first Godot version (when it was open sourced) had "MultiScript" which lets you use multiple scripts on one object.
With the addition of mulitple new scripting languages (VisualScript, soon C# and GDNative) it can be of use to combine scripts rather than delegating (with huge maintainance cost) or creating child nodes
which could impact performance.

I used the code from 0b806ee as the base and made it work with the current master.

7 files changed, 1049 insertions, 2 deletions

diff --git a/modules/gdscript/gd_script.cpp b/modules/gdscript/gd_script.cpp
index 2367f60740..fe20a842cf 100644
--- a/modules/gdscript/gd_script.cpp
+++ b/modules/gdscript/gd_script.cpp
@@ -1696,9 +1696,9 @@ void GDScriptLanguage::reload_tool_script(const Ref<Script> &p_script, bool p_so
 //same thing for placeholders
 #ifdef TOOLS_ENABLED
 
-			while (E->get()->placeholders.size()) {
+			for (Set<PlaceHolderScriptInstance *>::Element *P = E->get()->placeholders.front(); P; P = P->next()) {
 
-				Object *obj = E->get()->placeholders.front()->get()->get_owner();
+				Object *obj = P->get()->get_owner();
 				//save instance info
 				List<Pair<StringName, Variant> > state;
 				if (obj->get_script_instance()) {
diff --git a/modules/multiscript/SCsub b/modules/multiscript/SCsub
new file mode 100644
index 0000000000..0882406761
--- /dev/null
+++ b/modules/multiscript/SCsub
@@ -0,0 +1,7 @@
+#!/usr/bin/env python
+
+Import('env')
+
+env.add_source_files(env.modules_sources, "*.cpp")
+
+Export('env')
diff --git a/modules/multiscript/config.py b/modules/multiscript/config.py
new file mode 100644
index 0000000000..5698a37295
--- /dev/null
+++ b/modules/multiscript/config.py
@@ -0,0 +1,8 @@
+
+
+def can_build(platform):
+    return True
+
+
+def configure(env):
+    pass
diff --git a/modules/multiscript/multiscript.cpp b/modules/multiscript/multiscript.cpp
new file mode 100644
index 0000000000..b2633b7207
--- /dev/null
+++ b/modules/multiscript/multiscript.cpp
@@ -0,0 +1,750 @@
+/*************************************************************************/
+/*  multiscript.cpp                                                      */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                    http://www.godotengine.org                         */
+/*************************************************************************/
+/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+#include "multiscript.h"
+
+bool MultiScriptInstance::set(const StringName &p_name, const Variant &p_value) {
+
+	ScriptInstance **sarr = instances.ptr();
+	int sc = instances.size();
+
+	for (int i = 0; i < sc; i++) {
+
+		if (!sarr[i])
+			continue;
+
+		bool found = sarr[i]->set(p_name, p_value);
+		if (found)
+			return true;
+	}
+
+	if (String(p_name).begins_with("script_")) {
+		bool valid;
+		owner->set(p_name, p_value, &valid);
+		return valid;
+	}
+	return false;
+}
+
+bool MultiScriptInstance::get(const StringName &p_name, Variant &r_ret) const {
+
+	ScriptInstance **sarr = instances.ptr();
+	int sc = instances.size();
+
+	for (int i = 0; i < sc; i++) {
+
+		if (!sarr[i])
+			continue;
+
+		bool found = sarr[i]->get(p_name, r_ret);
+		if (found)
+			return true;
+	}
+	if (String(p_name).begins_with("script_")) {
+		bool valid;
+		r_ret = owner->get(p_name, &valid);
+		return valid;
+	}
+	return false;
+}
+void MultiScriptInstance::get_property_list(List<PropertyInfo> *p_properties) const {
+
+	ScriptInstance **sarr = instances.ptr();
+	int sc = instances.size();
+
+	Set<String> existing;
+
+	for (int i = 0; i < sc; i++) {
+
+		if (!sarr[i])
+			continue;
+
+		List<PropertyInfo> pl;
+		sarr[i]->get_property_list(&pl);
+
+		for (List<PropertyInfo>::Element *E = pl.front(); E; E = E->next()) {
+
+			if (existing.has(E->get().name))
+				continue;
+
+			p_properties->push_back(E->get());
+			existing.insert(E->get().name);
+		}
+	}
+
+	p_properties->push_back(PropertyInfo(Variant::NIL, "Scripts", PROPERTY_HINT_NONE, String(), PROPERTY_USAGE_CATEGORY));
+
+	for (int i = 0; i < owner->scripts.size(); i++) {
+
+		p_properties->push_back(PropertyInfo(Variant::OBJECT, "script_" + String::chr('a' + i), PROPERTY_HINT_RESOURCE_TYPE, "Script", PROPERTY_USAGE_EDITOR));
+	}
+
+	if (owner->scripts.size() < 25) {
+
+		p_properties->push_back(PropertyInfo(Variant::OBJECT, "script_" + String::chr('a' + (owner->scripts.size())), PROPERTY_HINT_RESOURCE_TYPE, "Script", PROPERTY_USAGE_EDITOR));
+	}
+}
+
+void MultiScriptInstance::get_method_list(List<MethodInfo> *p_list) const {
+
+	ScriptInstance **sarr = instances.ptr();
+	int sc = instances.size();
+
+	Set<StringName> existing;
+
+	for (int i = 0; i < sc; i++) {
+
+		if (!sarr[i])
+			continue;
+
+		List<MethodInfo> ml;
+		sarr[i]->get_method_list(&ml);
+
+		for (List<MethodInfo>::Element *E = ml.front(); E; E = E->next()) {
+
+			if (existing.has(E->get().name))
+				continue;
+
+			p_list->push_back(E->get());
+			existing.insert(E->get().name);
+		}
+	}
+}
+bool MultiScriptInstance::has_method(const StringName &p_method) const {
+
+	ScriptInstance **sarr = instances.ptr();
+	int sc = instances.size();
+
+	for (int i = 0; i < sc; i++) {
+
+		if (!sarr[i])
+			continue;
+
+		if (sarr[i]->has_method(p_method))
+			return true;
+	}
+
+	return false;
+}
+
+Variant MultiScriptInstance::call(const StringName &p_method, const Variant **p_args, int p_argcount, Variant::CallError &r_error) {
+
+	ScriptInstance **sarr = instances.ptr();
+	int sc = instances.size();
+
+	for (int i = 0; i < sc; i++) {
+
+		if (!sarr[i])
+			continue;
+
+		Variant r = sarr[i]->call(p_method, p_args, p_argcount, r_error);
+		if (r_error.error == Variant::CallError::CALL_OK)
+			return r;
+		else if (r_error.error != Variant::CallError::CALL_ERROR_INVALID_METHOD)
+			return r;
+	}
+
+	r_error.error = Variant::CallError::CALL_ERROR_INVALID_METHOD;
+	return Variant();
+}
+
+void MultiScriptInstance::call_multilevel(const StringName &p_method, const Variant **p_args, int p_argcount) {
+
+	ScriptInstance **sarr = instances.ptr();
+	int sc = instances.size();
+
+	for (int i = 0; i < sc; i++) {
+
+		if (!sarr[i])
+			continue;
+
+		sarr[i]->call_multilevel(p_method, p_args, p_argcount);
+	}
+}
+void MultiScriptInstance::notification(int p_notification) {
+
+	// ScriptInstance **sarr = instances.ptr();
+	int sc = instances.size();
+
+	for (int i = 0; i < sc; i++) {
+
+		ScriptInstance *instance = instances[i];
+
+		if (!instance)
+			continue;
+
+		instance->notification(p_notification);
+	}
+}
+
+Ref<Script> MultiScriptInstance::get_script() const {
+
+	return owner;
+}
+
+ScriptLanguage *MultiScriptInstance::get_language() {
+
+	return MultiScriptLanguage::get_singleton();
+}
+
+MultiScriptInstance::~MultiScriptInstance() {
+
+	owner->remove_instance(object);
+}
+
+Variant::Type MultiScriptInstance::get_property_type(const StringName &p_name, bool *r_is_valid) const {
+	bool valid = false;
+	Variant::Type type;
+
+	ScriptInstance **sarr = instances.ptr();
+	int sc = instances.size();
+
+	for (int i = 0; i < sc; i++) {
+
+		if (!sarr[i])
+			continue;
+
+		type = sarr[i]->get_property_type(p_name, &valid);
+		if (valid) {
+			*r_is_valid = valid;
+			return type;
+		}
+	}
+	*r_is_valid = false;
+	return Variant::NIL;
+}
+
+ScriptInstance::RPCMode MultiScriptInstance::get_rpc_mode(const StringName &p_method) const {
+	ScriptInstance **sarr = instances.ptr();
+	int sc = instances.size();
+
+	for (int i = 0; i < sc; i++) {
+
+		if (!sarr[i])
+			continue;
+		if (sarr[i]->has_method(p_method))
+			return sarr[i]->get_rpc_mode(p_method);
+	}
+	return RPC_MODE_DISABLED;
+}
+
+ScriptInstance::RPCMode MultiScriptInstance::get_rset_mode(const StringName &p_variable) const {
+	ScriptInstance **sarr = instances.ptr();
+	int sc = instances.size();
+
+	for (int i = 0; i < sc; i++) {
+
+		if (!sarr[i])
+			continue;
+
+		List<PropertyInfo> properties;
+		sarr[i]->get_property_list(&properties);
+
+		for (List<PropertyInfo>::Element *P = properties.front(); P; P = P->next()) {
+			if (P->get().name == p_variable) {
+				return sarr[i]->get_rset_mode(p_variable);
+			}
+		}
+	}
+	return RPC_MODE_DISABLED;
+}
+
+///////////////////
+
+bool MultiScript::is_tool() const {
+
+	for (int i = 0; i < scripts.size(); i++) {
+
+		if (scripts[i]->is_tool())
+			return true;
+	}
+
+	return false;
+}
+
+bool MultiScript::_set(const StringName &p_name, const Variant &p_value) {
+
+	_THREAD_SAFE_METHOD_
+
+	String s = String(p_name);
+	if (s.begins_with("script_")) {
+
+		int idx = s[7];
+		if (idx == 0)
+			return false;
+		idx -= 'a';
+
+		ERR_FAIL_COND_V(idx < 0, false);
+
+		Ref<Script> s = p_value;
+
+		if (idx < scripts.size()) {
+
+			if (s.is_null())
+				remove_script(idx);
+			else
+				set_script(idx, s);
+		} else if (idx == scripts.size()) {
+			if (s.is_null())
+				return false;
+			add_script(s);
+		} else
+			return false;
+
+		return true;
+	}
+
+	return false;
+}
+
+bool MultiScript::_get(const StringName &p_name, Variant &r_ret) const {
+
+	_THREAD_SAFE_METHOD_
+
+	String s = String(p_name);
+	if (s.begins_with("script_")) {
+
+		int idx = s[7];
+		if (idx == 0)
+			return false;
+		idx -= 'a';
+
+		ERR_FAIL_COND_V(idx < 0, false);
+
+		if (idx < scripts.size()) {
+
+			r_ret = get_script(idx);
+			return true;
+		} else if (idx == scripts.size()) {
+			r_ret = Ref<Script>();
+			return true;
+		}
+	}
+
+	return false;
+}
+void MultiScript::_get_property_list(List<PropertyInfo> *p_list) const {
+
+	_THREAD_SAFE_METHOD_
+
+	for (int i = 0; i < scripts.size(); i++) {
+
+		p_list->push_back(PropertyInfo(Variant::OBJECT, "script_" + String::chr('a' + i), PROPERTY_HINT_RESOURCE_TYPE, "Script"));
+	}
+
+	if (scripts.size() < 25) {
+
+		p_list->push_back(PropertyInfo(Variant::OBJECT, "script_" + String::chr('a' + (scripts.size())), PROPERTY_HINT_RESOURCE_TYPE, "Script"));
+	}
+}
+
+void MultiScript::set_script(int p_idx, const Ref<Script> &p_script) {
+
+	_THREAD_SAFE_METHOD_
+
+	ERR_FAIL_INDEX(p_idx, scripts.size());
+	ERR_FAIL_COND(p_script.is_null());
+
+	scripts[p_idx] = p_script;
+	Ref<Script> s = p_script;
+
+	for (Map<Object *, MultiScriptInstance *>::Element *E = instances.front(); E; E = E->next()) {
+
+		MultiScriptInstance *msi = E->get();
+		ScriptInstance *si = msi->instances[p_idx];
+		if (si) {
+			msi->instances[p_idx] = NULL;
+			memdelete(si);
+		}
+
+		if (p_script->can_instance())
+			msi->instances[p_idx] = s->instance_create(msi->object);
+	}
+}
+
+Ref<Script> MultiScript::get_script(int p_idx) const {
+
+	_THREAD_SAFE_METHOD_
+
+	ERR_FAIL_INDEX_V(p_idx, scripts.size(), Ref<Script>());
+
+	return scripts[p_idx];
+}
+void MultiScript::add_script(const Ref<Script> &p_script) {
+
+	_THREAD_SAFE_METHOD_
+	ERR_FAIL_COND(p_script.is_null());
+	Multi *script_owner = memnew(Multi);
+	script_instances.push_back(script_owner);
+	scripts.push_back(p_script);
+	Ref<Script> s = p_script;
+
+	for (Map<Object *, MultiScriptInstance *>::Element *E = instances.front(); E; E = E->next()) {
+
+		MultiScriptInstance *msi = E->get();
+
+		if (p_script->can_instance()) {
+			script_owner->real_owner = msi->object;
+			msi->instances.push_back(s->instance_create(script_owner));
+		} else {
+			msi->instances.push_back(NULL);
+		}
+
+		msi->object->_change_notify();
+	}
+
+	_change_notify();
+}
+
+void MultiScript::remove_script(int p_idx) {
+
+	_THREAD_SAFE_METHOD_
+
+	ERR_FAIL_INDEX(p_idx, scripts.size());
+
+	scripts.remove(p_idx);
+	script_instances.remove(p_idx);
+
+	for (Map<Object *, MultiScriptInstance *>::Element *E = instances.front(); E; E = E->next()) {
+
+		MultiScriptInstance *msi = E->get();
+		ScriptInstance *si = msi->instances[p_idx];
+		msi->instances.remove(p_idx);
+		if (si) {
+			memdelete(si);
+		}
+
+		msi->object->_change_notify();
+	}
+}
+
+void MultiScript::remove_instance(Object *p_object) {
+
+	_THREAD_SAFE_METHOD_
+	instances.erase(p_object);
+}
+
+bool MultiScript::can_instance() const {
+
+	return true;
+}
+
+StringName MultiScript::get_instance_base_type() const {
+
+	return StringName();
+}
+ScriptInstance *MultiScript::instance_create(Object *p_this) {
+
+	_THREAD_SAFE_METHOD_
+	MultiScriptInstance *msi = memnew(MultiScriptInstance);
+	msi->object = p_this;
+	msi->owner = this;
+
+	for (int i = 0; i < scripts.size(); i++) {
+
+		ScriptInstance *si;
+
+		if (scripts[i]->can_instance()) {
+			script_instances[i]->real_owner = p_this;
+			si = scripts[i]->instance_create(script_instances[i]);
+		} else {
+			si = NULL;
+		}
+
+		msi->instances.push_back(si);
+	}
+
+	instances[p_this] = msi;
+	p_this->_change_notify();
+	return msi;
+}
+bool MultiScript::instance_has(const Object *p_this) const {
+
+	_THREAD_SAFE_METHOD_
+	return instances.has((Object *)p_this);
+}
+
+bool MultiScript::has_source_code() const {
+
+	return false;
+}
+String MultiScript::get_source_code() const {
+
+	return "";
+}
+void MultiScript::set_source_code(const String &p_code) {
+}
+Error MultiScript::reload(bool p_keep_state) {
+
+	for (int i = 0; i < scripts.size(); i++)
+		scripts[i]->reload(p_keep_state);
+
+	return OK;
+}
+
+String MultiScript::get_node_type() const {
+
+	return "";
+}
+
+void MultiScript::_bind_methods() {
+}
+
+ScriptLanguage *MultiScript::get_language() const {
+
+	return MultiScriptLanguage::get_singleton();
+}
+
+///////////////
+
+MultiScript::MultiScript() {
+}
+
+MultiScript::~MultiScript() {
+	for (int i = 0; i < script_instances.size(); i++) {
+		memdelete(script_instances[i]);
+	}
+
+	script_instances.resize(0);
+}
+
+Ref<Script> MultiScript::get_base_script() const {
+	Ref<MultiScript> base_script;
+	return base_script;
+}
+
+bool MultiScript::has_method(const StringName &p_method) const {
+	for (int i = 0; i < scripts.size(); i++) {
+		if (scripts[i]->has_method(p_method)) {
+			return true;
+		}
+	}
+	return false;
+}
+
+MethodInfo MultiScript::get_method_info(const StringName &p_method) const {
+	for (int i = 0; i < scripts.size(); i++) {
+		if (scripts[i]->has_method(p_method)) {
+			return scripts[i]->get_method_info(p_method);
+		}
+	}
+	return MethodInfo();
+}
+
+bool MultiScript::has_script_signal(const StringName &p_signal) const {
+	for (int i = 0; i < scripts.size(); i++) {
+		if (scripts[i]->has_script_signal(p_signal)) {
+			return true;
+		}
+	}
+	return false;
+}
+
+void MultiScript::get_script_signal_list(List<MethodInfo> *r_signals) const {
+	for (int i = 0; i < scripts.size(); i++) {
+		scripts[i]->get_script_signal_list(r_signals);
+	}
+}
+
+bool MultiScript::get_property_default_value(const StringName &p_property, Variant &r_value) const {
+	for (int i = 0; i < scripts.size(); i++) {
+
+		if (scripts[i]->get_property_default_value(p_property, r_value)) {
+			return true;
+		}
+	}
+	return false;
+}
+
+void MultiScript::get_script_method_list(List<MethodInfo> *p_list) const {
+	for (int i = 0; i < scripts.size(); i++) {
+		scripts[i]->get_script_method_list(p_list);
+	}
+}
+
+void MultiScript::get_script_property_list(List<PropertyInfo> *p_list) const {
+	for (int i = 0; i < scripts.size(); i++) {
+		scripts[i]->get_script_property_list(p_list);
+	}
+}
+
+void MultiScript::update_exports() {
+	for (int i = 0; i < scripts.size(); i++) {
+		scripts[i]->update_exports();
+	}
+}
+
+MultiScriptLanguage *MultiScriptLanguage::singleton = NULL;
+
+MultiScriptLanguage *MultiScriptLanguage::get_singleton() {
+	return singleton;
+}
+
+String MultiScriptLanguage::get_name() const {
+	return "MultiScript";
+}
+
+void MultiScriptLanguage::init() {}
+
+String MultiScriptLanguage::get_type() const {
+	return "MultiScript";
+}
+
+String MultiScriptLanguage::get_extension() const {
+	return "";
+}
+
+Error MultiScriptLanguage::execute_file(const String &p_path) {
+	return OK;
+}
+
+void MultiScriptLanguage::finish() {}
+
+void MultiScriptLanguage::get_reserved_words(List<String> *p_words) const {}
+
+void MultiScriptLanguage::get_comment_delimiters(List<String> *p_delimiters) const {}
+
+void MultiScriptLanguage::get_string_delimiters(List<String> *p_delimiters) const {}
+
+Ref<Script> MultiScriptLanguage::get_template(const String &p_class_name, const String &p_base_class_name) const {
+	MultiScript *s = memnew(MultiScript);
+	s->base_class_name = p_base_class_name;
+	return Ref<MultiScript>(s);
+}
+
+bool MultiScriptLanguage::validate(const String &p_script, int &r_line_error, int &r_col_error, String &r_test_error, const String &p_path, List<String> *r_fn) const {
+	return true;
+}
+
+Script *MultiScriptLanguage::create_script() const {
+	return memnew(MultiScript);
+}
+
+bool MultiScriptLanguage::has_named_classes() const {
+	return false;
+}
+
+int MultiScriptLanguage::find_function(const String &p_function, const String &p_code) const {
+	return -1;
+}
+
+String MultiScriptLanguage::make_function(const String &p_class, const String &p_name, const PoolStringArray &p_args) const {
+	return "";
+}
+
+String MultiScriptLanguage::debug_get_error() const {
+	return "";
+}
+
+int MultiScriptLanguage::debug_get_stack_level_count() const {
+	return 0;
+}
+
+int MultiScriptLanguage::debug_get_stack_level_line(int p_level) const {
+	return 0;
+}
+
+String MultiScriptLanguage::debug_get_stack_level_function(int p_level) const {
+	return "";
+}
+
+String MultiScriptLanguage::debug_get_stack_level_source(int p_level) const {
+	return "";
+}
+
+void MultiScriptLanguage::debug_get_stack_level_locals(int p_level, List<String> *p_locals, List<Variant> *p_values, int p_max_subitems, int p_max_depth) {}
+
+void MultiScriptLanguage::debug_get_stack_level_members(int p_level, List<String> *p_members, List<Variant> *p_values, int p_max_subitems, int p_max_depth) {}
+
+void MultiScriptLanguage::debug_get_globals(List<String> *p_locals, List<Variant> *p_values, int p_max_subitems, int p_max_depth) {}
+
+String MultiScriptLanguage::debug_parse_stack_level_expression(int p_level, const String &p_expression, int p_max_subitems, int p_max_depth) {
+	return "";
+}
+
+void MultiScriptLanguage::get_recognized_extensions(List<String> *p_extensions) const {}
+
+void MultiScriptLanguage::get_public_functions(List<MethodInfo> *p_functions) const {}
+
+MultiScriptLanguage::MultiScriptLanguage() {
+	singleton = this;
+}
+
+MultiScriptLanguage::~MultiScriptLanguage() {}
+
+void MultiScriptLanguage::auto_indent_code(String &p_code, int p_from_line, int p_to_line) const {
+}
+
+void MultiScriptLanguage::add_global_constant(const StringName &p_variable, const Variant &p_value) {
+}
+
+void MultiScriptLanguage::reload_all_scripts() {
+}
+
+void MultiScriptLanguage::reload_tool_script(const Ref<Script> &p_script, bool p_soft_reload) {
+}
+
+void MultiScriptLanguage::get_public_constants(List<Pair<String, Variant> > *p_constants) const {
+}
+
+void MultiScriptLanguage::profiling_start() {
+}
+
+void MultiScriptLanguage::profiling_stop() {
+}
+
+int MultiScriptLanguage::profiling_get_accumulated_data(ScriptLanguage::ProfilingInfo *p_info_arr, int p_info_max) {
+	return 0;
+}
+
+int MultiScriptLanguage::profiling_get_frame_data(ScriptLanguage::ProfilingInfo *p_info_arr, int p_info_max) {
+	return 0;
+}
+
+void Multi::_bind_methods() {
+	// ClassDB::bind_method("call", &Multi::call);
+	// ClassDB::bind_method("call_multilevel", &Multi::call_multilevel);
+	// ClassDB::bind_method("call_multilevel_reversed", &Multi::call_multilevel_reversed);
+}
+
+Variant Multi::call(const StringName &p_method, const Variant **p_args, int p_argcount, Variant::CallError &r_error) {
+	if (real_owner)
+		return real_owner->call(p_method, p_args, p_argcount, r_error);
+	return Variant();
+}
+
+void Multi::call_multilevel(const StringName &p_method, const Variant **p_args, int p_argcount) {
+	if (real_owner)
+		real_owner->call_multilevel(p_method, p_args, p_argcount);
+}
+
+void Multi::call_multilevel_reversed(const StringName &p_method, const Variant **p_args, int p_argcount) {
+	if (real_owner)
+		real_owner->call_multilevel_reversed(p_method, p_args, p_argcount);
+}
diff --git a/modules/multiscript/multiscript.h b/modules/multiscript/multiscript.h
new file mode 100644
index 0000000000..7ec1d5402f
--- /dev/null
+++ b/modules/multiscript/multiscript.h
@@ -0,0 +1,200 @@
+/*************************************************************************/
+/*  multiscript.h                                                        */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                    http://www.godotengine.org                         */
+/*************************************************************************/
+/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+#ifndef MULTISCRIPT_H
+#define MULTISCRIPT_H
+
+#include "os/thread_safe.h"
+#include "script_language.h"
+
+class MultiScript;
+
+class Multi : public Object {
+	GDCLASS(Multi, Object)
+
+	friend class MultiScript;
+
+	Object *real_owner;
+
+public:
+	static void _bind_methods();
+
+	virtual Variant call(const StringName &p_method, const Variant **p_args, int p_argcount, Variant::CallError &r_error);
+	virtual void call_multilevel(const StringName &p_method, const Variant **p_args, int p_argcount);
+	virtual void call_multilevel_reversed(const StringName &p_method, const Variant **p_args, int p_argcount);
+};
+
+class MultiScriptInstance : public ScriptInstance {
+	friend class MultiScript;
+	mutable Vector<ScriptInstance *> instances;
+	Object *object;
+	mutable MultiScript *owner;
+
+public:
+	virtual bool set(const StringName &p_name, const Variant &p_value);
+	virtual bool get(const StringName &p_name, Variant &r_ret) const;
+	virtual void get_property_list(List<PropertyInfo> *p_properties) const;
+
+	virtual void get_method_list(List<MethodInfo> *p_list) const;
+	virtual bool has_method(const StringName &p_method) const;
+	virtual Variant call(const StringName &p_method, const Variant **p_args, int p_argcount, Variant::CallError &r_error);
+	virtual void call_multilevel(const StringName &p_method, const Variant **p_args, int p_argcount);
+	virtual void notification(int p_notification);
+
+	virtual Ref<Script> get_script() const;
+
+	virtual ScriptLanguage *get_language();
+	virtual ~MultiScriptInstance();
+
+	// ScriptInstance interface
+public:
+	Variant::Type get_property_type(const StringName &p_name, bool *r_is_valid) const;
+	RPCMode get_rpc_mode(const StringName &p_method) const;
+	RPCMode get_rset_mode(const StringName &p_variable) const;
+};
+
+class MultiScript : public Script {
+
+	_THREAD_SAFE_CLASS_
+	friend class MultiScriptInstance;
+	friend class MultiScriptLanguage;
+	GDCLASS(MultiScript, Script)
+
+	StringName base_class_name;
+
+	Vector<Ref<Script> > scripts;
+	Vector<Multi *> script_instances;
+
+	Map<Object *, MultiScriptInstance *> instances;
+
+protected:
+	bool _set(const StringName &p_name, const Variant &p_value);
+	bool _get(const StringName &p_name, Variant &r_ret) const;
+	void _get_property_list(List<PropertyInfo> *p_list) const;
+
+	static void _bind_methods();
+
+public:
+	void remove_instance(Object *p_object);
+	virtual bool can_instance() const;
+
+	virtual StringName get_instance_base_type() const;
+	virtual ScriptInstance *instance_create(Object *p_this);
+	virtual bool instance_has(const Object *p_this) const;
+
+	virtual bool has_source_code() const;
+	virtual String get_source_code() const;
+	virtual void set_source_code(const String &p_code);
+	virtual Error reload(bool p_keep_state = false);
+
+	virtual bool is_tool() const;
+
+	virtual String get_node_type() const;
+
+	void set_script(int p_idx, const Ref<Script> &p_script);
+	Ref<Script> get_script(int p_idx) const;
+	void remove_script(int p_idx);
+	void add_script(const Ref<Script> &p_script);
+
+	virtual ScriptLanguage *get_language() const;
+
+	MultiScript();
+	~MultiScript();
+
+	virtual Ref<Script> get_base_script() const;
+	virtual bool has_method(const StringName &p_method) const;
+	virtual MethodInfo get_method_info(const StringName &p_method) const;
+	virtual bool has_script_signal(const StringName &p_signal) const;
+	virtual void get_script_signal_list(List<MethodInfo> *r_signals) const;
+	virtual bool get_property_default_value(const StringName &p_property, Variant &r_value) const;
+	virtual void get_script_method_list(List<MethodInfo> *p_list) const;
+	virtual void get_script_property_list(List<PropertyInfo> *p_list) const;
+	virtual void update_exports();
+};
+
+class MultiScriptLanguage : public ScriptLanguage {
+
+	static MultiScriptLanguage *singleton;
+
+public:
+	static _FORCE_INLINE_ MultiScriptLanguage *get_singleton();
+	virtual String get_name() const;
+
+	/* LANGUAGE FUNCTIONS */
+	virtual void init();
+	virtual String get_type() const;
+	virtual String get_extension() const;
+	virtual Error execute_file(const String &p_path);
+	virtual void finish();
+
+	/* EDITOR FUNCTIONS */
+	virtual void get_reserved_words(List<String> *p_words) const;
+	virtual void get_comment_delimiters(List<String> *p_delimiters) const;
+	virtual void get_string_delimiters(List<String> *p_delimiters) const;
+	virtual Ref<Script> get_template(const String &p_class_name, const String &p_base_class_name) const;
+	virtual bool validate(const String &p_script, int &r_line_error, int &r_col_error, String &r_test_error, const String &p_path = "", List<String> *r_fn = NULL) const;
+	virtual Script *create_script() const;
+	virtual bool has_named_classes() const;
+	virtual int find_function(const String &p_function, const String &p_code) const;
+	virtual String make_function(const String &p_class, const String &p_name, const PoolStringArray &p_args) const;
+
+	/* DEBUGGER FUNCTIONS */
+
+	virtual String debug_get_error() const;
+	virtual int debug_get_stack_level_count() const;
+	virtual int debug_get_stack_level_line(int p_level) const;
+	virtual String debug_get_stack_level_function(int p_level) const;
+	virtual String debug_get_stack_level_source(int p_level) const;
+	virtual void debug_get_stack_level_locals(int p_level, List<String> *p_locals, List<Variant> *p_values, int p_max_subitems = -1, int p_max_depth = -1);
+	virtual void debug_get_stack_level_members(int p_level, List<String> *p_members, List<Variant> *p_values, int p_max_subitems = -1, int p_max_depth = -1);
+	virtual void debug_get_globals(List<String> *p_locals, List<Variant> *p_values, int p_max_subitems = -1, int p_max_depth = -1);
+	virtual String debug_parse_stack_level_expression(int p_level, const String &p_expression, int p_max_subitems = -1, int p_max_depth = -1);
+
+	/* LOADER FUNCTIONS */
+
+	virtual void get_recognized_extensions(List<String> *p_extensions) const;
+	virtual void get_public_functions(List<MethodInfo> *p_functions) const;
+
+	MultiScriptLanguage();
+	virtual ~MultiScriptLanguage();
+
+	// ScriptLanguage interface
+public:
+	void auto_indent_code(String &p_code, int p_from_line, int p_to_line) const;
+	void add_global_constant(const StringName &p_variable, const Variant &p_value);
+	void reload_all_scripts();
+	void reload_tool_script(const Ref<Script> &p_script, bool p_soft_reload);
+	void get_public_constants(List<Pair<String, Variant> > *p_constants) const;
+	void profiling_start();
+	void profiling_stop();
+	int profiling_get_accumulated_data(ProfilingInfo *p_info_arr, int p_info_max);
+	int profiling_get_frame_data(ProfilingInfo *p_info_arr, int p_info_max);
+};
+
+#endif // MULTISCRIPT_H
diff --git a/modules/multiscript/register_types.cpp b/modules/multiscript/register_types.cpp
new file mode 100644
index 0000000000..8170a2d9c1
--- /dev/null
+++ b/modules/multiscript/register_types.cpp
@@ -0,0 +1,51 @@
+/*************************************************************************/
+/*  register_types.cpp                                                   */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                    http://www.godotengine.org                         */
+/*************************************************************************/
+/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+#include "register_types.h"
+
+#include "multiscript.h"
+
+#include "core/script_language.h"
+
+static MultiScriptLanguage *script_multi_script = NULL;
+
+void register_multiscript_types() {
+	script_multi_script = memnew(MultiScriptLanguage);
+	ScriptServer::register_language(script_multi_script);
+	ClassDB::register_class<MultiScript>();
+
+	// ClassDB::register_class<Multi>();
+}
+
+void unregister_multiscript_types() {
+	if (script_multi_script) {
+		ScriptServer::unregister_language(script_multi_script);
+		memdelete(script_multi_script);
+	}
+}
diff --git a/modules/multiscript/register_types.h b/modules/multiscript/register_types.h
new file mode 100644
index 0000000000..b18d1adff2
--- /dev/null
+++ b/modules/multiscript/register_types.h
@@ -0,0 +1,31 @@
+/*************************************************************************/
+/*  register_types.h                                                     */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                    http://www.godotengine.org                         */
+/*************************************************************************/
+/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+void register_multiscript_types();
+void unregister_multiscript_types();