Cocos2d-x 3.1 Lua Binding

Cocos2d-x 3.1 Lua Binding

參考：http://www.cocos2d-x.org/docs/manual/code-ide/binding-custom-class-to-lua/en

添加須要綁定的C++類

在xcode中，把my文件夾拖到cocos2d_libs.xcodeproj中

HNLuaTest.h

//
//  HNLuaTest.h
//  cocos2d_libs
//
//  Created by Eleven Chen on 14-8-5.
//
//

#ifndef __cocos2d_libs__HNLuaTest__
#define __cocos2d_libs__HNLuaTest__

#include "cocos2d.h"
#include <string>


class Test : public cocos2d::Ref
{
public:
    
    static std::string helloMsg();
    
    static Test* create();
    
    bool init();
    static cocos2d::Vec2 left();
};

#endif /* defined(__cocos2d_libs__HNLuaTest__) */

HNLuaTest.cpp

//
//  HNLuaTest.cpp
//  cocos2d_libs
//
//  Created by Eleven Chen on 14-8-5.
//
//

#include "HNLuaTest.h"
using namespace cocos2d;

std::string Test::helloMsg()
{
    return "Hello from  HNLuaTest::helloMsg()";
}

Test* Test::create()
{
    return new Test();
}

bool Test::init()
{
    return true;
}

Vec2 Test::left()
{
    return Vec2(0, 0);
}

編寫ini文件

進入到tolua目錄：$(PROJECT_ROOT)/frameworks/cocos2d-x/tools/tolua

在以前先看看README文件，並安裝好環境。

README文件中提到必需要用android ndk r9b來編譯，由於編譯的時候用到了C++ std 4.7的頭文件，而r9b包含了4.7，我用的是r9d，只有4.6和4.8。我把*.ini文件裏面的4.7改爲4.8來編譯。

新建一個cocos2dx_custom.ini文件，而後從其餘文件裏面copy一份代碼過來修改，代碼裏面每個設置都有詳細的註釋。

[cocos2dx_custom]
# the prefix to be added to the generated functions. You might or might not use this in your own
# templates
prefix = cocos2dx_custom

# create a target namespace (in javascript, this would create some code like the equiv. to `ns = ns || {}`)
# all classes will be embedded in that namespace
target_namespace = cc

# the native namespace in which this module locates, this parameter is used for avoid conflict of the same class name in different modules, as "cocos2d::Label" <-> "cocos2d::ui::Label".
cpp_namespace = 

android_headers = -I%(androidndkdir)s/platforms/android-14/arch-arm/usr/include -I%(androidndkdir)s/sources/cxx-stl/gnu-libstdc++/4.8/libs/armeabi-v7a/include -I%(androidndkdir)s/sources/cxx-stl/gnu-libstdc++/4.8/include
android_flags = -D_SIZE_T_DEFINED_ 

clang_headers = -I%(clangllvmdir)s/lib/clang/3.3/include 
clang_flags = -nostdinc -x c++ -std=c++11

cocos_headers = -I%(cocosdir)s/cocos -I%(cocosdir)s/cocos/editor-support -I%(cocosdir)s/cocos/platform/android

cocos_flags = -DANDROID

cxxgenerator_headers = 

# extra arguments for clang
extra_arguments = %(android_headers)s %(clang_headers)s %(cxxgenerator_headers)s %(cocos_headers)s %(android_flags)s %(clang_flags)s %(cocos_flags)s %(extra_flags)s 

# what headers to parse
headers =  %(cocosdir)s/cocos/my/HNLuaTest.h

# what classes to produce code for. You can use regular expressions here. When testing the regular
# expression, it will be enclosed in "^$", like this: "^Menu*$".
classes = Test.*

# what should we skip? in the format ClassName::[function function]
# ClassName is a regular expression, but will be used like this: "^ClassName$" functions are also
# regular expressions, they will not be surrounded by "^$". If you want to skip a whole class, just
# add a single "*" as functions. See bellow for several examples. A special class name is "*", which
# will apply to all class names. This is a convenience wildcard to be able to skip similar named
# functions from all classes.

skip = 

rename_functions = 

rename_classes =

# for all class names, should we remove something when registering in the target VM?
remove_prefix = 

# classes for which there will be no "parent" lookup
classes_have_no_parents = Test

# base classes which will be skipped when their sub-classes found them.
base_classes_to_skip =

# classes that create no constructor
# Set is special and we will use a hand-written constructor
abstract_classes = 

# Determining whether to use script object(js object) to control the lifecycle of native(cpp) object or the other way around. Supported values are 'yes' or 'no'.
script_control_cpp = no

編寫genbindings.py

爲了方便，每次綁定時不須要生成cocos2d-x的綁定代碼，新建一個genbindings_custom.py文件，而後複製genbindings.py的代碼過來，把下面的地方：

cmd_args = {'cocos2dx.ini' : ('cocos2d-x', 'lua_cocos2dx_auto'), \
                    'cocos2dx_extension.ini' : ('cocos2dx_extension', 'lua_cocos2dx_extension_auto'), \
                    'cocos2dx_ui.ini' : ('cocos2dx_ui', 'lua_cocos2dx_ui_auto'), \
                    'cocos2dx_studio.ini' : ('cocos2dx_studio', 'lua_cocos2dx_studio_auto'), \
                    'cocos2dx_spine.ini' : ('cocos2dx_spine', 'lua_cocos2dx_spine_auto'), \
                    'cocos2dx_physics.ini' : ('cocos2dx_physics', 'lua_cocos2dx_physics_auto'), \
                    'custom.ini': ('custom', 'lua_custom_auto'), \
                    'cocos2dx_custom.ini' : ('cocos2dx_custom', 'lua_cocos2dx_custom_auto'), \
                    }

改成

cmd_args = {'cocos2dx_custom.ini' : ('cocos2dx_custom', 'lua_cocos2dx_custom_auto'), \
                    }

運行genbindings_custom.py

./genbindings_custom.py

生成的代碼在 cocos/scripting/lua-bindings/auto裏面

mac和ios的集成

• 把生成的hpp和cpp拖到cocos2d_lua_bindings.xcodeproj/auto中

• 在cocos2d_lua_bindings.xcodeproj 的Build Settings中設置頭文件搜索，添加my

Android集成

• 在my文件夾中添加Android.mk文件，以下內容

LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)

LOCAL_MODULE := cocos_custom_static

LOCAL_MODULE_FILENAME := libmy

LOCAL_SRC_FILES := \
HNLuaTest.cpp

LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH) \
$(LOCAL_PATH)./

LOCAL_C_INCLUDES := $(LOCAL_PATH) \
$(LOCAL_PATH)./

LOCAL_CFLAGS += -Wno-psabi
LOCAL_EXPORT_CFLAGS += -Wno-psabi

LOCAL_WHOLE_STATIC_LIBRARIES := cocos2dx_static

include $(BUILD_STATIC_LIBRARY)

$(call import-module,.)

• 打開lua-bindings文件夾的Android.mk文件，添加如下內容

LOCAL_SRC_FILES := manual/CCLuaBridge.cpp \
                                #省略
                                auto/lua_cocos2dx_custom_auto.cpp \
                                ../../../external/lua/tolua/tolua_event.c \
                                #省略

註冊到Lua

修改AppDelegate.cpp

//register custom function
    //LuaStack* stack = engine->getLuaStack();
    //register_custom_function(stack->getLuaState());
    LuaStack *stack = engine->getLuaStack();
    auto L = stack->getLuaState();
    if (L)
    {
        lua_getglobal(L, "_G");
        register_all_cocos2dx_custom(L);
        lua_settop(L, 0);
    }
    
#if (COCOS2D_DEBUG>0)
    if (startRuntime())
        return true;
#endif
    engine->executeScriptFile(ConfigParser::getInstance()->getEntryFile().c_str());
    return true;

這裏不能按照本來代碼註釋的方法那樣作，那樣會出錯。

並且都是tolua_module這個函數裏面的 lua_rawget(L,-2);這一行出錯。

緣由是：

1. auto engine = LuaEngine::getInstance();
2. _defaultEngine->init();
3. executeScriptFile("Deprecated.lua");
4. _stack->clean();
5. lua_settop(_state, 0);

LuaEngine初始化的時候會運行3個lua文件，把stack給清空了。

在tolua_module函數中，lua_pushstring(L,name);後，棧只有一個元素，因此lua_rawget(L,-2);就會出錯。

只須要把_G放到棧中，再運行register_all_cocos2dx_custom(L);，若是模塊不在_G中，就添加到_G中，就能夠全局訪問了。

cocos code ide build custom runtime

測試

-- test custom
 local msg = cc.Test:helloMsg()
 print(msg)

輸出

綁定時候使用本身的命名空間

打開：cocos2d-x/tools/bindings-generator/targets/lua/conversions.yaml文件 在ns_map添加本身的命名空間：

ns_map:
    "cocos2d::extension::": "cc."
    "cocos2d::ui::": "ccui."
    "cocos2d::": "cc."
    "spine::": "sp."
    "cocostudio::": "ccs."
    "cocosbuilder::": "cc."
    "CocosDenshion::": "cc."
    # 我本身的命名空間
    "hunuo::": "hn."