调用lua函数executeGlobalFunction
闲来无事,搞了搞cocos2dx的lua脚本,话说lua这东西几年前学过一段时间,也自己开发过c++接口,做过一些小东西,不过时间久远,记忆模糊。捡起来还是费了点功夫,下面就是我的一些体会。
cocos2dx使用的是tolua++来制作的lua接口,tolua++文档不多,网上的一些文章也是答非所问,所以自己看代码是最佳学习途径。
cocos2dx操作lua的类是CCLuaEngine,其中实现了加载与实行lua脚本,以及操作lua stack。
LuaCocos2d.cpp很主要,文件的开头注释也说明其是由tolua++自动生成的,我们想在lua中操作自己定义的类就是通过修改此文件实现的,两个重要函数是void tolua_reg_types (lua_State* tolua_S)与int tolua_Cocos2d_open (lua_State* tolua_S),前者是注册自定义类型,后者是定义其接口,调用关系是tolua_Cocos2d_open调用tolua_reg_types,而tolua_Cocos2d_open是在CCLuaEngine的init中调用的。
假设我要向lua注册新类,那么首先我要在tolua_reg_types中添加一行注册代码,然后在tolua_Cocos2d_open添加其接口说明,我将这两个步骤定义成两个函数,单独在一个文件中实现,文件名为cwLuaReg.cpp,内容为:
#include "cwLuaReg.h"
#include "cwGameObject.h"
#include "cwCollisionObject.h"
#include "cwGravityObject.h"
#ifdef __cplusplus
static int tolua_collect_cwGameObject(lua_State* tolua_S)
{
cwGameObject* self = (cwGameObject*) tolua_tousertype(tolua_S,1,0);
delete self;
return 0;
}
static int tolua_collect_cwGravityObject(lua_State* tolua_S)
{
cwGravityObject* self = (cwGravityObject*) tolua_tousertype(tolua_S,1,0);
delete self;
return 0;
}
#ifndef TOLUA_DISABLE_tolua_cw_GameObject_create00
static int tolua_cw_GameObject_create00(lua_State* tolua_S)
{
tolua_Error tolua_err;
if(!tolua_isusertable(tolua_S,1,"cwGameObject",0,&tolua_err) ||
!tolua_isnoobj(tolua_S,2,&tolua_err))
goto tolua_lerror;
else
{
{
cwGameObject* tolua_ret = (cwGameObject*) cwGameObject::create();
int nID = (tolua_ret) ? (int)tolua_ret->m_uID : -1;
int* pLuaID = (tolua_ret) ? &tolua_ret->m_nLuaID : NULL;
toluafix_pushusertype_ccobject(tolua_S, nID, pLuaID, (void*)tolua_ret,"cwGameObject");
}
}
return 1;
tolua_lerror:
return 0;
}
#endif //#ifndef TOLUA_DISABLE
#ifndef TOLUA_DISABLE_tolua_cw_GameObject_getSpeed00
static int tolua_cw_GameObject_getSpeed00(lua_State* tolua_S)
{
#ifndef TOLUA_RELEASE
tolua_Error tolua_err;
if (!tolua_isusertype(tolua_S,1,"cwGameObject",0,&tolua_err) ||
!tolua_isnoobj(tolua_S,2,&tolua_err))
goto tolua_lerror;
else
#endif
{
cwGameObject* self = (cwGameObject*) tolua_tousertype(tolua_S,1,0);
#ifndef TOLUA_RELEASE
if (!self) tolua_error(tolua_S,"invalid 'self' in function 'speed'", NULL);
#endif
{
float tolua_ret = (float) self->speed();
tolua_pushnumber(tolua_S,(lua_Number)tolua_ret);
}
}
return 1;
#ifndef TOLUA_RELEASE
tolua_lerror:
tolua_error(tolua_S,"#ferror in function 'speed'.",&tolua_err);
return 0;
#endif
}
#endif
#ifndef TOLUA_DISABLE_tolua_cw_GameObject_setSpeed00
static int tolua_cw_GameObject_setSpeed00(lua_State* tolua_S)
{
#ifndef TOLUA_RELEASE
tolua_Error tolua_err;
if (!tolua_isusertype(tolua_S,1,"cwGameObject",0,&tolua_err) ||
!tolua_isnumber(tolua_S,2,0,&tolua_err) ||
!tolua_isnoobj(tolua_S,3,&tolua_err))
goto tolua_lerror;
else
#endif
{
cwGameObject* self = (cwGameObject*) tolua_tousertype(tolua_S,1,0);
float speed = ((float) tolua_tonumber(tolua_S,2,0));
#ifndef TOLUA_RELEASE
if (!self) tolua_error(tolua_S,"invalid 'self' in function 'setSpeed'", NULL);
#endif
{
self->setSpeed(speed);
}
}
return 0;
#ifndef TOLUA_RELEASE
tolua_lerror:
tolua_error(tolua_S,"#ferror in function 'setSpeed'.",&tolua_err);
return 0;
#endif
}
#endif
#ifndef TOLUA_DISABLE_tolua_cw_GameObject_getMoveDir00
static int tolua_cw_GameObject_getMoveDir00(lua_State* tolua_S)
{
#ifndef TOLUA_RELEASE
tolua_Error tolua_err;
if (!tolua_isusertype(tolua_S,1,"cwGameObject",0,&tolua_err) ||
!tolua_isnoobj(tolua_S,2,&tolua_err))
goto tolua_lerror;
else
#endif
{
cwGameObject* self = (cwGameObject*) tolua_tousertype(tolua_S,1,0);
#ifndef TOLUA_RELEASE
if (!self) tolua_error(tolua_S,"invalid 'self' in function 'getMoveDir'", NULL);
#endif
cwVector2D& dir = self->moveDir();
tolua_pushnumber(tolua_S,(lua_Number)dir.x);
tolua_pushnumber(tolua_S,(lua_Number)dir.y);
}
return 2;
#ifndef TOLUA_RELEASE
tolua_lerror:
tolua_error(tolua_S,"#ferror in function 'getMoveDir'.",&tolua_err);
return 0;
#endif
}
#endif
#ifndef TOLUA_DISABLE_tolua_cw_GameObject_setMoveDir00
static int tolua_cw_GameObject_setMoveDir00(lua_State* tolua_S)
{
#ifndef TOLUA_RELEASE
tolua_Error tolua_err;
if (!tolua_isusertype(tolua_S,1,"cwGameObject",0,&tolua_err) ||
!tolua_isnumber(tolua_S,2,0,&tolua_err) ||
!tolua_isnumber(tolua_S,3,0,&tolua_err) ||
!tolua_isnoobj(tolua_S,4,&tolua_err))
goto tolua_lerror;
else
#endif
{
cwGameObject* self = (cwGameObject*) tolua_tousertype(tolua_S,1,0);
float dirX = ((float) tolua_tonumber(tolua_S,2,0));
float dirY = ((float) tolua_tonumber(tolua_S,3,0));
#ifndef TOLUA_RELEASE
if (!self) tolua_error(tolua_S,"invalid 'self' in function 'setMoveDir'", NULL);
#endif
self->setMoveDir(dirX, dirY);
}
return 0;
#ifndef TOLUA_RELEASE
tolua_lerror:
tolua_error(tolua_S,"#ferror in function 'getMoveDir'.",&tolua_err);
return 0;
#endif
}
#endif
#endif
TOLUA_API int tolua_cwLua_reg_types(lua_State* tolua_S)
{
//add by sunny
tolua_usertype(tolua_S,"cwGameObject");
tolua_usertype(tolua_S,"cwGravityObject");
//end sunny
return 1;
}
TOLUA_API int tolua_cwLua_reg(lua_State* tolua_S)
{
#ifdef __cplusplus
tolua_cclass(tolua_S,"cwGameObject","cwGameObject","CCSprite",tolua_collect_cwGameObject);
#else
tolua_cclass(tolua_S,"cwGameObject","cwGameObject","CCSprite",NULL);
#endif
tolua_beginmodule(tolua_S,"cwGameObject");
tolua_function(tolua_S,"create",tolua_cw_GameObject_create00);
tolua_function(tolua_S,"speed",tolua_cw_GameObject_getSpeed00);
tolua_function(tolua_S,"setSpeed",tolua_cw_GameObject_setSpeed00);
tolua_function(tolua_S,"moveDir",tolua_cw_GameObject_getMoveDir00);
tolua_function(tolua_S,"setMoveDir",tolua_cw_GameObject_setMoveDir00);
tolua_endmodule(tolua_S);
#ifdef __cplusplus
tolua_cclass(tolua_S,"cwGravityObject","cwGravityObject","cwGameObject",tolua_collect_cwGravityObject);
#else
tolua_cclass(tolua_S,"cwGravityObject","cwGravityObject","cwGameObject",NULL);
#endif
tolua_beginmodule(tolua_S,"cwGravityObject");
tolua_endmodule(tolua_S);
return 1;
}
将tolua_cwLua_reg_types和tolua_cwLua_reg分别加到LuaCocos2d.cpp对应函数末尾,这样两个类cwGameObject与cwGravityObject就可以在lua中使用了。
做到这还不能达到我的期望,原因是cocos2d的lua工程里,在AppDelegate::applicationDidFinishLaunching函数中只是加载并执行了hello.lua脚本文件,然后一切就都交给lua了,而我只是想使用lua实现一些AI方面的功能,即cwGameObject在需要执行AI时,调用lua中的一个函数。所以我需要的是一个可以调用lua函数的功能,查看了一下CCLuaEngine类,貌似没有我想要的,只能自己添了个函数:
virtual int executeGlobalFunction(const char* functionName, float dt, CCObject* pObject, const char* typeName);
functionName:被调lua函数名;dt:帧时间间隔;pObject:调用lua的对象;typeName:pObject对象类型
实现如下:
int CCLuaEngine::executeGlobalFunction(const char* functionName, float dt, CCObject* pObject, const char* typeName)
{
lua_getglobal(m_state, functionName);
if (!lua_isfunction(m_state, -1))
{
CCLOG("[LUA ERROR] name '%s' does not represent a Lua function", functionName);
lua_pop(m_state, 1);
return 0;
}
pushFloat(dt);
pushCCObject(pObject, typeName);
int error = lua_pcall(m_state, 2, 1, 0);
if (error)
{
CCLOG("[LUA ERROR] %s", lua_tostring(m_state, - 1));
lua_pop(m_state, 1); // clean error message
return 0;
}
// get return value
if (!lua_isnumber(m_state, -1))
{
lua_pop(m_state, 1);
return 0;
}
int ret = lua_tointeger(m_state, -1);
lua_pop(m_state, 1);
return ret;
}
基本上是照着其他函数扒下来的,不同之处就是加了两个push。
函数写的比较死,可以写一个接受可变参数的函数,做的通用些。
假设我要在cwGameObject的upadte函数中调用“do_obj_update”lua函数,写法如下:
void cwGameObject::update(float dt)
{
CCLuaEngine::defaultEngine()->executeGlobalFunction("do_obj_update", dt, this,"cwGameObject");
}
这样在创建cwGameObject时scheduleUpdate一下就可以了。
lua脚本:
-- for CCLuaEngine traceback
function __G__TRACKBACK__(msg)
print("----------------------------------------")
print("LUA ERROR: " .. tostring(msg) .. "\n")
print(debug.traceback())
print("----------------------------------------")
end
winSize = CCDirector:sharedDirector():getWinSize()
-- avoid memory leak
collectgarbage("setpause", 100)
collectgarbage("setstepmul", 5000)
function do_obj_update(dt, obj)
local x, y = obj:getPosition()
local vx, vy = obj:moveDir()
x = x + vx*dt*obj:speed()
y = y + vy*dt*obj:speed()
if x < 0 then
x = 0
obj:setMoveDir(-vx, vy)
end
if x > winSize.width then
x = winSize.width
obj:setMoveDir(-vx, vy)
end
if y < 0 then
y = 0
obj:setMoveDir(vx, -vy)
end
if y > winSize.height then
y = winSize.height
obj:setMoveDir(vx, -vy)
end
obj:setPosition(x, y)
end
print("test.lua loaded.")
脚本很简单,do_obj_update函数只是做了一些边框判断。
别忘了修改AppDelegate::applicationDidFinishLaunching中加载的脚本文件名~~
cocos2dx使用的是tolua++来制作的lua接口,tolua++文档不多,网上的一些文章也是答非所问,所以自己看代码是最佳学习途径。
cocos2dx操作lua的类是CCLuaEngine,其中实现了加载与实行lua脚本,以及操作lua stack。
LuaCocos2d.cpp很主要,文件的开头注释也说明其是由tolua++自动生成的,我们想在lua中操作自己定义的类就是通过修改此文件实现的,两个重要函数是void tolua_reg_types (lua_State* tolua_S)与int tolua_Cocos2d_open (lua_State* tolua_S),前者是注册自定义类型,后者是定义其接口,调用关系是tolua_Cocos2d_open调用tolua_reg_types,而tolua_Cocos2d_open是在CCLuaEngine的init中调用的。
假设我要向lua注册新类,那么首先我要在tolua_reg_types中添加一行注册代码,然后在tolua_Cocos2d_open添加其接口说明,我将这两个步骤定义成两个函数,单独在一个文件中实现,文件名为cwLuaReg.cpp,内容为:
#include "cwLuaReg.h"
#include "cwGameObject.h"
#include "cwCollisionObject.h"
#include "cwGravityObject.h"
#ifdef __cplusplus
static int tolua_collect_cwGameObject(lua_State* tolua_S)
{
cwGameObject* self = (cwGameObject*) tolua_tousertype(tolua_S,1,0);
delete self;
return 0;
}
static int tolua_collect_cwGravityObject(lua_State* tolua_S)
{
cwGravityObject* self = (cwGravityObject*) tolua_tousertype(tolua_S,1,0);
delete self;
return 0;
}
#ifndef TOLUA_DISABLE_tolua_cw_GameObject_create00
static int tolua_cw_GameObject_create00(lua_State* tolua_S)
{
tolua_Error tolua_err;
if(!tolua_isusertable(tolua_S,1,"cwGameObject",0,&tolua_err) ||
!tolua_isnoobj(tolua_S,2,&tolua_err))
goto tolua_lerror;
else
{
{
cwGameObject* tolua_ret = (cwGameObject*) cwGameObject::create();
int nID = (tolua_ret) ? (int)tolua_ret->m_uID : -1;
int* pLuaID = (tolua_ret) ? &tolua_ret->m_nLuaID : NULL;
toluafix_pushusertype_ccobject(tolua_S, nID, pLuaID, (void*)tolua_ret,"cwGameObject");
}
}
return 1;
tolua_lerror:
return 0;
}
#endif //#ifndef TOLUA_DISABLE
#ifndef TOLUA_DISABLE_tolua_cw_GameObject_getSpeed00
static int tolua_cw_GameObject_getSpeed00(lua_State* tolua_S)
{
#ifndef TOLUA_RELEASE
tolua_Error tolua_err;
if (!tolua_isusertype(tolua_S,1,"cwGameObject",0,&tolua_err) ||
!tolua_isnoobj(tolua_S,2,&tolua_err))
goto tolua_lerror;
else
#endif
{
cwGameObject* self = (cwGameObject*) tolua_tousertype(tolua_S,1,0);
#ifndef TOLUA_RELEASE
if (!self) tolua_error(tolua_S,"invalid 'self' in function 'speed'", NULL);
#endif
{
float tolua_ret = (float) self->speed();
tolua_pushnumber(tolua_S,(lua_Number)tolua_ret);
}
}
return 1;
#ifndef TOLUA_RELEASE
tolua_lerror:
tolua_error(tolua_S,"#ferror in function 'speed'.",&tolua_err);
return 0;
#endif
}
#endif
#ifndef TOLUA_DISABLE_tolua_cw_GameObject_setSpeed00
static int tolua_cw_GameObject_setSpeed00(lua_State* tolua_S)
{
#ifndef TOLUA_RELEASE
tolua_Error tolua_err;
if (!tolua_isusertype(tolua_S,1,"cwGameObject",0,&tolua_err) ||
!tolua_isnumber(tolua_S,2,0,&tolua_err) ||
!tolua_isnoobj(tolua_S,3,&tolua_err))
goto tolua_lerror;
else
#endif
{
cwGameObject* self = (cwGameObject*) tolua_tousertype(tolua_S,1,0);
float speed = ((float) tolua_tonumber(tolua_S,2,0));
#ifndef TOLUA_RELEASE
if (!self) tolua_error(tolua_S,"invalid 'self' in function 'setSpeed'", NULL);
#endif
{
self->setSpeed(speed);
}
}
return 0;
#ifndef TOLUA_RELEASE
tolua_lerror:
tolua_error(tolua_S,"#ferror in function 'setSpeed'.",&tolua_err);
return 0;
#endif
}
#endif
#ifndef TOLUA_DISABLE_tolua_cw_GameObject_getMoveDir00
static int tolua_cw_GameObject_getMoveDir00(lua_State* tolua_S)
{
#ifndef TOLUA_RELEASE
tolua_Error tolua_err;
if (!tolua_isusertype(tolua_S,1,"cwGameObject",0,&tolua_err) ||
!tolua_isnoobj(tolua_S,2,&tolua_err))
goto tolua_lerror;
else
#endif
{
cwGameObject* self = (cwGameObject*) tolua_tousertype(tolua_S,1,0);
#ifndef TOLUA_RELEASE
if (!self) tolua_error(tolua_S,"invalid 'self' in function 'getMoveDir'", NULL);
#endif
cwVector2D& dir = self->moveDir();
tolua_pushnumber(tolua_S,(lua_Number)dir.x);
tolua_pushnumber(tolua_S,(lua_Number)dir.y);
}
return 2;
#ifndef TOLUA_RELEASE
tolua_lerror:
tolua_error(tolua_S,"#ferror in function 'getMoveDir'.",&tolua_err);
return 0;
#endif
}
#endif
#ifndef TOLUA_DISABLE_tolua_cw_GameObject_setMoveDir00
static int tolua_cw_GameObject_setMoveDir00(lua_State* tolua_S)
{
#ifndef TOLUA_RELEASE
tolua_Error tolua_err;
if (!tolua_isusertype(tolua_S,1,"cwGameObject",0,&tolua_err) ||
!tolua_isnumber(tolua_S,2,0,&tolua_err) ||
!tolua_isnumber(tolua_S,3,0,&tolua_err) ||
!tolua_isnoobj(tolua_S,4,&tolua_err))
goto tolua_lerror;
else
#endif
{
cwGameObject* self = (cwGameObject*) tolua_tousertype(tolua_S,1,0);
float dirX = ((float) tolua_tonumber(tolua_S,2,0));
float dirY = ((float) tolua_tonumber(tolua_S,3,0));
#ifndef TOLUA_RELEASE
if (!self) tolua_error(tolua_S,"invalid 'self' in function 'setMoveDir'", NULL);
#endif
self->setMoveDir(dirX, dirY);
}
return 0;
#ifndef TOLUA_RELEASE
tolua_lerror:
tolua_error(tolua_S,"#ferror in function 'getMoveDir'.",&tolua_err);
return 0;
#endif
}
#endif
#endif
TOLUA_API int tolua_cwLua_reg_types(lua_State* tolua_S)
{
//add by sunny
tolua_usertype(tolua_S,"cwGameObject");
tolua_usertype(tolua_S,"cwGravityObject");
//end sunny
return 1;
}
TOLUA_API int tolua_cwLua_reg(lua_State* tolua_S)
{
#ifdef __cplusplus
tolua_cclass(tolua_S,"cwGameObject","cwGameObject","CCSprite",tolua_collect_cwGameObject);
#else
tolua_cclass(tolua_S,"cwGameObject","cwGameObject","CCSprite",NULL);
#endif
tolua_beginmodule(tolua_S,"cwGameObject");
tolua_function(tolua_S,"create",tolua_cw_GameObject_create00);
tolua_function(tolua_S,"speed",tolua_cw_GameObject_getSpeed00);
tolua_function(tolua_S,"setSpeed",tolua_cw_GameObject_setSpeed00);
tolua_function(tolua_S,"moveDir",tolua_cw_GameObject_getMoveDir00);
tolua_function(tolua_S,"setMoveDir",tolua_cw_GameObject_setMoveDir00);
tolua_endmodule(tolua_S);
#ifdef __cplusplus
tolua_cclass(tolua_S,"cwGravityObject","cwGravityObject","cwGameObject",tolua_collect_cwGravityObject);
#else
tolua_cclass(tolua_S,"cwGravityObject","cwGravityObject","cwGameObject",NULL);
#endif
tolua_beginmodule(tolua_S,"cwGravityObject");
tolua_endmodule(tolua_S);
return 1;
}
将tolua_cwLua_reg_types和tolua_cwLua_reg分别加到LuaCocos2d.cpp对应函数末尾,这样两个类cwGameObject与cwGravityObject就可以在lua中使用了。
做到这还不能达到我的期望,原因是cocos2d的lua工程里,在AppDelegate::applicationDidFinishLaunching函数中只是加载并执行了hello.lua脚本文件,然后一切就都交给lua了,而我只是想使用lua实现一些AI方面的功能,即cwGameObject在需要执行AI时,调用lua中的一个函数。所以我需要的是一个可以调用lua函数的功能,查看了一下CCLuaEngine类,貌似没有我想要的,只能自己添了个函数:
virtual int executeGlobalFunction(const char* functionName, float dt, CCObject* pObject, const char* typeName);
functionName:被调lua函数名;dt:帧时间间隔;pObject:调用lua的对象;typeName:pObject对象类型
实现如下:
int CCLuaEngine::executeGlobalFunction(const char* functionName, float dt, CCObject* pObject, const char* typeName)
{
lua_getglobal(m_state, functionName);
if (!lua_isfunction(m_state, -1))
{
CCLOG("[LUA ERROR] name '%s' does not represent a Lua function", functionName);
lua_pop(m_state, 1);
return 0;
}
pushFloat(dt);
pushCCObject(pObject, typeName);
int error = lua_pcall(m_state, 2, 1, 0);
if (error)
{
CCLOG("[LUA ERROR] %s", lua_tostring(m_state, - 1));
lua_pop(m_state, 1); // clean error message
return 0;
}
// get return value
if (!lua_isnumber(m_state, -1))
{
lua_pop(m_state, 1);
return 0;
}
int ret = lua_tointeger(m_state, -1);
lua_pop(m_state, 1);
return ret;
}
基本上是照着其他函数扒下来的,不同之处就是加了两个push。
函数写的比较死,可以写一个接受可变参数的函数,做的通用些。
假设我要在cwGameObject的upadte函数中调用“do_obj_update”lua函数,写法如下:
void cwGameObject::update(float dt)
{
CCLuaEngine::defaultEngine()->executeGlobalFunction("do_obj_update", dt, this,"cwGameObject");
}
这样在创建cwGameObject时scheduleUpdate一下就可以了。
lua脚本:
-- for CCLuaEngine traceback
function __G__TRACKBACK__(msg)
print("----------------------------------------")
print("LUA ERROR: " .. tostring(msg) .. "\n")
print(debug.traceback())
print("----------------------------------------")
end
winSize = CCDirector:sharedDirector():getWinSize()
-- avoid memory leak
collectgarbage("setpause", 100)
collectgarbage("setstepmul", 5000)
function do_obj_update(dt, obj)
local x, y = obj:getPosition()
local vx, vy = obj:moveDir()
x = x + vx*dt*obj:speed()
y = y + vy*dt*obj:speed()
if x < 0 then
x = 0
obj:setMoveDir(-vx, vy)
end
if x > winSize.width then
x = winSize.width
obj:setMoveDir(-vx, vy)
end
if y < 0 then
y = 0
obj:setMoveDir(vx, -vy)
end
if y > winSize.height then
y = winSize.height
obj:setMoveDir(vx, -vy)
end
obj:setPosition(x, y)
end
print("test.lua loaded.")
脚本很简单,do_obj_update函数只是做了一些边框判断。
别忘了修改AppDelegate::applicationDidFinishLaunching中加载的脚本文件名~~
cocos2dx版本:cocos2d-2.0-x-2.0.3
http://blog.csdn.net/honghaier/article/details/8700574