oasisscriptluainterpreter.cpp

使用stl技术,(还没看,是听说的)

/******************************************************************************
 * This source file is part of Bad Camel Gaming
 * Copyright (C) 2003  Zephie Greyvenstein
 * See Readme.html for acknowledgements
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *****************************************************************************/

/******************************************************************************
 * FILENAME    : oasisScriptLuaInterpreter.cpp
 * DESCRIPTION : The grunt of the lua language.
 * AUTHOR      : Gaw ([e-mail])
 *****************************************************************************/
//only compile if Lua is included in the library
#ifdef HAS_LUA
#include <vector>

#include "oasisScriptInterpreter.h"
#include "oasisScriptSystem.h"
#include "oasisVector3.h"
#include "oasisQuaternion.h"
#include "oasisScriptLuaInterpreter.h"

#include "OgreLogManager.h"

extern int tolua_engine_open( lua_State * );

namespace Oasis {
  
  scriptLuaInterpreter::scriptLuaInterpreter( ) 
    : scriptInterpreter( ) {   
    luaInterpreter = lua_open( ); 
    loadLibs( );
  }
  
  scriptLuaInterpreter::~scriptLuaInterpreter( ) {
    lua_close( luaInterpreter );
  }

  bool scriptLuaInterpreter::executeScript( string &name ) {
    scriptSystem::get( ).scriptLog( "Attempting to load " + name );
    return !lua_dofile( luaInterpreter, name.c_str( ) );
  }

  void *scriptLuaInterpreter::executeString( string &name, uint8 &type ) {
    int top = lua_gettop( luaInterpreter );
    lua_dostring( luaInterpreter, name.c_str( ) );
    //If anything in the size of the stack has changed, you have a return value
    //note the above technique doesn't work because a sub-interpreter
    //is started to evaluate the string.
    if( lua_gettop( luaInterpreter ) - top ) 
      return convertToC( ( void * ) NULL, type );
    
    type = '0';
    return ( void * ) NULL;
  }

  void scriptLuaInterpreter::reset( ) {
    lua_close( luaInterpreter );
    luaInterpreter = lua_open( ); 
    loadLibs( );
  }

  //This function displays errors to the console.
  int errorHandler( lua_State *L ) {
    string error = lua_tostring( L, 1 );
    scriptSystem::get( ).scriptLog( error );
    return 1;
  }
  
  void scriptLuaInterpreter::loadLibs( ) {
    lua_register( luaInterpreter, "_ALERT", ( lua_CFunction )&errorHandler );
    lua_register( luaInterpreter, "_OUTPUT", ( lua_CFunction )&errorHandler );
    luaopen_base( luaInterpreter ); 
    luaopen_table( luaInterpreter );
    luaopen_io( luaInterpreter );
    luaopen_string( luaInterpreter );
    luaopen_math( luaInterpreter );
    luaopen_debug( luaInterpreter ); 
    luaopen_loadlib( luaInterpreter ); 
    tolua_engine_open( luaInterpreter );
  }

  void scriptLuaInterpreter::loadLibrary(
                            int ( *callback )( lua_State * ) ) {
    callback( luaInterpreter ); 
  }

  void *scriptLuaInterpreter::convertFromC( void *cObject, uint8 type ) {
    //conversion from and to the stack are intertwined, pushing it on
    //now would only be error prone, this is done later.  During callFunction
    return cObject;
  }
  void scriptLuaInterpreter::_convertFromC( void *cObject, uint8 type ) {
    int i;
    //numbers
    if( type == 'i' || type == 'd' ) 
      lua_pushnumber( luaInterpreter, ( real ) *( int32 * ) cObject );
    else if( type == 'r' || type == 'f' )
      lua_pushnumber( luaInterpreter, *( real * ) cObject );

    //bool
    else if( type == 'b' ) 
      lua_pushboolean( luaInterpreter, *( bool * ) cObject );
    
    
    //vector
    else if( type == 'v' ) {
      lua_newtable( luaInterpreter );
      lua_pushnumber( luaInterpreter, ( ( vector3 * ) cObject )->z );
      lua_pushnumber( luaInterpreter, ( ( vector3 * ) cObject )->y );
      lua_pushnumber( luaInterpreter, ( ( vector3 * ) cObject )->x );
      for( i = 0; i < 3; i++ ) 
        lua_rawseti( luaInterpreter, -( 4-i ), i+1 );
      lua_pushstring( luaInterpreter, "n" );
      lua_pushnumber( luaInterpreter, 3 );
      lua_settable( luaInterpreter, -3 );
    }
    
    //quaternion
    else if( type == 'q' ) {
      lua_newtable( luaInterpreter );
      lua_pushnumber( luaInterpreter, ( ( quaternion * ) cObject )->z );
      lua_pushnumber( luaInterpreter, ( ( quaternion * ) cObject )->y );
      lua_pushnumber( luaInterpreter, ( ( quaternion * ) cObject )->x );
      lua_pushnumber( luaInterpreter, ( ( quaternion * ) cObject )->w );
      for( i = 0; i<4; i++ ) 
        lua_rawseti( luaInterpreter, -( 5-i ), i+1 );
      lua_pushstring( luaInterpreter, "n" );
      lua_pushnumber( luaInterpreter, 4 );
      lua_settable( luaInterpreter, -3 );
    }
    
    //character
    else if( type == 'c' ) {
      char tmpstr[2];
      tmpstr[0] =  *( char * )cObject ;
      tmpstr[1] = 0;
      lua_pushstring( luaInterpreter, tmpstr );
    }
    else if( type == 's' ) 
     lua_pushstring( luaInterpreter, ( char * ) cObject ); 
    else 
      scriptSystem::get( ).scriptLog(
         " Error, bad typed passed to callFunction->_convertFromC " );
  }

  void *scriptLuaInterpreter::convertToC( void *scriptObject, uint8 &type ) {
    void *ret;
    int index = lua_gettop( luaInterpreter );
    int toptype = lua_type( luaInterpreter, index );
    
    if ( toptype == LUA_TBOOLEAN ) { 
      ret = ( void * ) new bool( lua_toboolean( luaInterpreter, index ) );
      type = 'b';
    }
        
    else if ( toptype == LUA_TNUMBER ) { 
      ret = ( void * ) new real( lua_tonumber( luaInterpreter, index ) );
      type = 'r';
    }
    
    else if ( toptype == LUA_TSTRING ) {
      ret = ( void * ) lua_tostring( luaInterpreter, index );
      type = 's';
    }
        
    //We are only supporting vectors and quaternions,
    //so the list must 1) be linear and 2) contain either
    //3 or 4 elements of type real.
    else if ( toptype == LUA_TTABLE ) {
      std::vector < real > list;
      int i = 1;
      
      for( ; ; i++ ) {
        //Get array entry 'index' and push result on stack
        lua_rawgeti( luaInterpreter, index, i ); 
        //nil signifies no other entries in array
        //-1 means the top element in the stack.
        if( lua_isnil( luaInterpreter, -1 )) break;  
        //PENDING: What happens when this isn't a number?
        list.push_back( lua_tonumber( luaInterpreter, -1 ) );
        lua_pop( luaInterpreter, 1 );
      }
      //clean up the nil element
      lua_pop( luaInterpreter, 1 );

      if( list.size() == 3 ) {
        ret = ( void * ) new vector3( list[0], list[1], list[2] );
        type = 'v';
      }
      else if( list.size() == 4 ) {
        ret = ( void * ) new quaternion( list[0], list[1],
                            list[2], list[3] );
        type = 'q';
      }
      //Should never be more than 4.
      else {
        ret = ( void * ) NULL;
        type = '0';
      }
    }

    //Let's support passing in the type 'quaternion' and 'vector3'
    else if( toptype == LUA_TUSERDATA || toptype == LUA_TLIGHTUSERDATA ) {
      lua_getmetatable( luaInterpreter, index );
      //http://celestia.teyssier.org/lxr/source/src/celestia/celx.cpp
      lua_rawget( luaInterpreter, LUA_REGISTRYINDEX );

      //If the class isn't registered
      if( lua_type( luaInterpreter, -1 ) != LUA_TSTRING ) {
        lua_pop( luaInterpreter, 1 );
        type = '0';
        return ( void * ) NULL;
      }

      const char *name = lua_tostring( luaInterpreter, -1 );      
      lua_pop( luaInterpreter, 1 );
      //invalid name
      if( !name ) {
        type = '0';
        ret = ( void * ) NULL;
      }

      //vector3
      else if(strcmp( name, "vector3" ) == 0) {
        vector3 *flua = ( vector3 * ) 
                lua_touserdata( luaInterpreter, index );
        ret = new vector3( flua->x, flua->y, flua->z );
        type = 'v';
      }

      //quaternion
      else if(strcmp( name, "quaternion" ) == 0) {
        quaternion *flua = ( quaternion * )
                lua_touserdata( luaInterpreter, index );
        ret = new quaternion( flua->w, flua->x, flua->y, flua->z );
        type = 'q';
      }
    }
    
    else {
      ret = ( void * ) NULL;
      type = '0';
    }

    return ret;
  }

  void *scriptLuaInterpreter::callFunction( string &name, string &types, 
                                        void **arguments,
                                        uint8 &returntype ) {
    int i;
    int top = lua_gettop( luaInterpreter );
    //Lookup our function in the globals table.
    lua_pushstring( luaInterpreter, name.c_str( ) );
    lua_gettable( luaInterpreter, LUA_GLOBALSINDEX );
    //push the arguments on the stack.
    //PENDING:  Do these arguments get reversed?
    for( i=0; i < types.length( ); i++ ) {
      _convertFromC( arguments[i], types[i] );
    }
    lua_call( luaInterpreter, types.length(), 1 ); 
    
    if( top < lua_gettop( luaInterpreter ) )
      return convertToC( ( void * ) NULL, returntype );
    else {
      returntype = '0';
      return ( void * ) NULL;
    }
  }
  void scriptLuaInterpreter::freeVariable( void *script_var ) {
  }
};

#endif