portal: combating the space-detection issue.
what needs to be tweaked next is how far away objects are spawned.
it should either be a trial&error adjustment or depend on the object's moving direction and the portal's angle in order to avoid issues with box collisions.
if the spawn distance to the portal is just a fixed value (as it was before this patch) or a constant factor (it is now) it can be too big for "nice" portal angles (in tight gaps with still enough space, but -> denied) and too small for bad angles (box collision esp. on big objects like barrels -> denied)
/*
** $Id: lualib.h,v 1.36.1.1 2007/12/27 13:02:25 roberto Exp $
** Lua standard libraries
** See Copyright Notice in lua.h
*/
#ifndef lualib_h
#define lualib_h
#include "lua.h"
/* Key to file-handle type */
#define LUA_FILEHANDLE "FILE*"
#define LUA_COLIBNAME "coroutine"
LUALIB_API int (luaopen_base) (lua_State *L);
#define LUA_TABLIBNAME "table"
LUALIB_API int (luaopen_table) (lua_State *L);
#define LUA_IOLIBNAME "io"
LUALIB_API int (luaopen_io) (lua_State *L);
#define LUA_OSLIBNAME "os"
LUALIB_API int (luaopen_os) (lua_State *L);
#define LUA_STRLIBNAME "string"
LUALIB_API int (luaopen_string) (lua_State *L);
#define LUA_MATHLIBNAME "math"
LUALIB_API int (luaopen_math) (lua_State *L);
#define LUA_DBLIBNAME "debug"
LUALIB_API int (luaopen_debug) (lua_State *L);
#define LUA_LOADLIBNAME "package"
LUALIB_API int (luaopen_package) (lua_State *L);
/* open all previous libraries */
LUALIB_API void (luaL_openlibs) (lua_State *L);
#ifndef lua_assert
#define lua_assert(x) ((void)0)
#endif
#endif