This collection of classes provides a framework whereby the engine
may provide scripting capabilities in any "context". A C++
function may declare a plugin context by providing a list of names
function objects, then may call "play_slice()" on this context to
transfer control to lua. A lua script may generate some arguments
and request to call some of these, then yield to the engine. C++
will run them until one of them signals an error, or that the
context is now invalid (using a boolean return value).
The intended semantics is that lua may only make requests
corresponding to the current context. As soon as a new context
is used (play_slice() is called again) the old context is invalid
from lua's point of view -- calling those functions is a lua
error but not undefined behavior. This should be the case even if
the old context has not been destroyed yet in C++, for instance
if a lua request resulted in a new context being created. There is
a system of locks in place to ensure that when old contexts are
invalidated, stale requests are discarded.
We also add the coroutine library to our lua base. This because
threads are run as coroutines, and writing them requires the use
of coroutine yield from the standard library.
The lua show dialog used to get the video object from resources,
which is not ideal. In this version, lua kernel base internalizes
a pointer to the video object, and show_dialog is bound to a
method of the lua kernel base.
From now on, lua kernels which want to show dialogs need to be
constructed with a pointer to a CVideo, if it is null the lua will
fail with a runtime error.
The application lua kernel is constructed with the video for
game_launcher, and the game lua kernel is modified so that it is
owned by the play controller and not the game events manager, and
held in a boost scoped pointer rather than manually deleted. This
is because the game events manager doesn't have a video object,
also it conceptually seems independent of the lua kernel anyways.
The map generator lua kernels are constructed with NULL, but if a
user configuration dialog is provided (new feature) then when they
try to run it they will update with the mp_create's video pointer.
- Add an internal command logger to the lua kernel base, and expose
this.
- Redirect the internal lua `print` to the command logger.
- Add an external logger registration system to lua kernel, in
addition to the internal one.
- Add a lua console dialog which binds to a lua kernel base and
permits to review the contents of the logger and issue new commands,
and report errors.
- Add a hotkey binding to launch the lua console "`"
- Adds tab completion support to the lua console
In initial commit of the new lua kernels, I introduced a problem
by trying to use luaW_pcall and lua_pcall interchangeably via
polymorphism. This doesn't work because their return types don't
match, and it's alot of work to change luaW_pcall syntax. Besides
this there's no reason we can't use the custom error handler
everywhere.
This commits adds protected_call and load_string functions to lua
kernel base. These are an intended replacement for luaW_pcall,
and replace the "run" function. They do better error reporting
and allow to specify an error handler.
The error reporting is very flexible -- by default we select a
an error reporting function associated polymorphically to the lua
kernel, so the in-game lua kernel can send chat messages, and
others can do something else. However an arbitrary handler may
be specified, and exceptions instead of logging may also be
requested.
The application lua kernel is meant to interpret scripts to drive
the client. Its main features are, it stores a script in its
registry and provides a C++ function to call it with a config
as its argument. Its initialization also creates a "game_launcher"
object, which stands as a limited lua proxy for the C++
game_launcher object.
The game_launcher object is a table, holding a pointer to the
actual game_launcher it represents, and with metamethods to return
version info and the command line arguments. It also holds
callbacks to set the script for the current application lua kernel,
and to call the "play_multiplayer" function of game_launcher.
Currently it is readonly and you cannot write to its fields,
although that may change to allow the target server to be reset,
etc.
Some minor changes that are included in this commit:
- the actual C++ game launcher object provides an accessor to the
command line options.
- the scripting/lua_types.hpp file now has include guards
