c++调用lua的基本操作

目标: 用c++读取下面lua文件的变量，表，调用函数：

由于还有些表要我配，今天任务延期，没完成，明日再更新

name = "织法"
age = 25
color = {r=1.0,g=0.2,b=0.5,a=1.0}
arr = {1,2,3,4,5}
function Add(a,b)
    return a+b
end
function Squar(num)
    return num * num
end
function Dist2D(pointA,pointB)
    local xdst = pointA.x - pointB.x
    local ydst = pointA.y - pointB.y
    return math.sqrt(Squar(xdst) + Squar(ydst))
end
print("hello lua")

c++ luabase.h

#pragma once
#include<string>
#include<cstring>
#include<cstdlib>
#include<cstdio>
using namespace std;
#include "lua.hpp"

extern lua_State *L;

struct luaColor
{
    double r, g, b, a;
    void output();
};

struct luaVec2D
{
    int x, y;
    luaVec2D(int v_x, int v_y)
    {
        x = v_x;
        y = v_y;
    }
    ~luaVec2D() {}
    void pushToLuaState() const;
};

bool lua_checkf(int err);
#define LUA_CHECK(f) do{if(!lua_checkf(f))\
        return false;}while(0)
void loadLua();
void cloaseLua();
int loadInteger(const char* v_key);
const char* loadString(const char* v_key);
int lua_add(int a, int b);
bool loadColor(luaColor *v_color);
bool loadArr(int *arr, int n);
bool calPointDis(const luaVec2D &p1, const luaVec2D &p2, double &rst);

 

c++ luabase.cpp

#include"luabase.h"

lua_State *L;

bool lua_checkf(int err)
{
    if (!err)
    {
        printf("报错啦，错误信息是%s\n", lua_tostring(L, -1));
        return false;
    }
    return true;
}

#define LUA_CHECK(f) do{if(!lua_checkf(f))\
        return false;}while(0)


void loadLua()
{
    const string filename = "lua/test.lua";
    L = luaL_newstate();
    luaopen_base(L);
    luaL_openlibs(L);
    luaL_dofile(L, filename.data());
}

void cloaseLua()
{
    lua_close(L);
}

int loadInteger(const char* v_key)
{
    LUA_CHECK(lua_getglobal(L, v_key));
    int rst = lua_tointeger(L, -1);
    lua_pop(L, 1);
    return rst;
}

const char* loadString(const char* v_key)
{
    LUA_CHECK(lua_getglobal(L, v_key));
    lua_pop(L, 1);
    return lua_tostring(L, -1);
}

int lua_add(int a,int b)
{
    lua_getglobal(L, "Add");
    lua_pushinteger(L, a);
    lua_pushinteger(L, b);
    //All arguments and the function value are popped from the stack when the function is called
    if (lua_pcall(L, 2, 1, 0) != LUA_OK)
    {
        printf("报错啦，错误信息是%s\n",lua_tostring(L, -1));
    }
    int rst = lua_tointeger(L, -1);
    lua_pop(L, 1);//result
    return rst;
}

bool loadColor(luaColor *v_color)
{
    LUA_CHECK(lua_getglobal(L, "color"));
    LUA_CHECK(lua_getfield(L, -1, "r"));
    v_color->r = lua_tonumber(L, -1);
    lua_pop(L, 1);
    LUA_CHECK(lua_getfield(L, -1, "g"));
    v_color->g = lua_tonumber(L, -1);
    lua_pop(L, 1);
    LUA_CHECK(lua_getfield(L, -1, "b"));
    v_color->b = lua_tonumber(L, -1);
    lua_pop(L, 1);
    LUA_CHECK(lua_getfield(L, -1, "a"));
    v_color->a = lua_tonumber(L, -1);
    lua_pop(L, 1);
    lua_pop(L, 1);
    return true;
}

bool loadArr(int *arr, int n)
{
    LUA_CHECK(lua_getglobal(L, "arr"));
    for (int i = 1; i <= n; i++)
    {
        lua_pushnumber(L, i);
        LUA_CHECK(lua_gettable(L, -2));
        arr[i - 1] = lua_tointeger(L, -1);
        lua_pop(L,1);
    }
    lua_pop(L, 1);
    return true;
}

bool calPointDis(const luaVec2D &p1,const luaVec2D &p2,double &rst)
{
    LUA_CHECK(lua_getglobal(L, "Dist2D"));
    p1.pushToLuaState();
    p2.pushToLuaState();
    if (lua_pcall(L, 2, 1, 0) != LUA_OK)
    {
        printf("报错啦，错误信息是%s\n", lua_tostring(L, -1));
        return false;
    }
    rst = lua_tonumber(L, -1);
    lua_pop(L, 1);
    return true;
}

void luaColor::output()
{
    printf("color:{%d,%d,%d,%d}\n", (int)(r*255), (int)(g*255), (int)(b*255), (int)(a*255));
}

void luaVec2D::pushToLuaState()const
{
    lua_newtable(L);
    lua_pushstring(L, "x");
    lua_pushnumber(L, (lua_Number)x);
    //lua_settable(L, -3);
    lua_rawset(L, -3);
    lua_pushstring(L, "y");
    lua_pushnumber(L, (lua_Number)y);
    lua_rawset(L, -3);
}

 

 Main函数：

#include"luabase.h"

void printArr(int *arr, int n);


int main()
{
    loadLua();
    //printf("result = %d\n", rst
    int age = loadInteger("age");
    printf("age: %d\n", age);
    const char* name = loadString("name");
    printf("name: %s\n", name);
    int addrst = lua_add(2, 3);
    printf("call add 2 3 return %d\n", addrst);
    luaColor color;
    loadColor(&color);
    color.output();
    int arr[5];
    loadArr(arr, 5);
    printArr(arr, 5);
    luaVec2D p1(0,3), p2(4,0);
    double dist = 0;
    calPointDis(p1, p2, dist);
    printf("dis = %.2lf\n", dist);
    cloaseLua();
    system("pause");
    return 0;
}

void printArr(int *arr, int n)
{
    printf("arr: ");
    for (int i = 0; i < n; i++)
    {
        if (i)printf(" ");
        printf("%d",arr[i]);
    }
    printf("\n");
}