SamVanheer
commented
8 years ago I've added interfaces for the client side. I opted to keep the server and client interfaces separate to prevent versioning issues if shared interfaces were ever modified.
As with the server, there are 2 interfaces: IClientEngine: a new interface to the engine, this covers much of IServerEngine's new additions, as well as the ability to play sounds by index. This is very important because it allows the server to send sound indices to clients instead of being forced to send sample names. In some cases, like the event system, there is no way to send strings at all, so there is no way to tell clients to play sounds that way. PlaySoundByIndex would allow you to pass an integer argument along to play it, which is very useful to have.
It can be found here: https://github.com/SamVanheer/HLEnhanced/blob/iface_proposal/shared/engine/client/IClientEngine.h
Ideally, an entirely new interface for sounds could be added where all current and new sound methods are centralized.
IClientGameLib: like IServerGameLib, this provides missing callbacks. The ability to connect with other libraries is present in LibInit, and callbacks at specific moments allows the client to initialize and clean itself up. The client gains the ability to detect to which server a connection has been established (currently impossible), as well as the ability to reject connections on its own if the server's info doesn't meet criteria (e.g. missing or present tags).
A callback to notify when a map is about to start loading allows it to initialize per-map data, for example parsing worldspawn's entity data to load a keyvalue from it. I'm using that to load a script on the client side to handle client side scripting operations. Currently this requires a hack which has timing issues, with server network messages arriving before my hack gets to run.
It can be found here: https://github.com/SamVanheer/HLEnhanced/blob/iface_proposal/shared/game/client/IClientGameLib.h
I am aware that the client already has the means to connect to other libraries in IClientVGUI. However, that interface is not included in the SDK. I would like to request the addition of this interface, as well as the entire GoldSource era VGUI2 library code so mods can use it as well. Additionally, utility code compatible with it (CUtlDict, CUtlVector, KeyValues, etc) would be greatly appreciated. If any documentation exists for this, that would also be appreciated.
Lastly, experimentation has shown that Steamworks is accessible in the game libraries. If possible, could Steamworks access be given to game code? This would allow direct access to query for data, like client Steam IDs, server tags, etc.
I would like to request the addition of new interfaces for engine <-> game communication. The existing interfaces do not cover all necessary areas of game dev and can require ugly workarounds to achieve certain goals.
To that end, i have designed a proposal for a set of interfaces to allow communication between the server and the engine.
There are 2 interfaces in this proposal: IServerEngine: a new interface to the engine, this adds missing functionality, such as the ability to check what the highest entity index currently in use is, whether a model/sound/file has been precached, and whether a client has fully authenticated.
It can be found here: https://github.com/SamVanheer/HLEnhanced/blob/iface_proposal/shared/engine/server/IServerEngine.h
IServerGameLib: an interface that represents the server as a library and provides core callbacks needed to inform the server of map state changes in the engine. This is CRITICAL in order to write proper code, especially when it comes to initializing and cleaning up per-map data. It also provides a means to get any and all interfaces from any engine library, including the client, should it be a listen server.
It also includes the ability to handle entity creation on map start in the server, which allows for many improvements in map spawn logic. E.g. custom entities can be handled better than depending on global state to track when custom entities are being created.
The ability to handle game physics (excluding players, handled in pm_shared.cpp) also exists in it, allowing mods to implement completely custom physics.
Last but not least, a callback to notify when a client has fully authenticated also exists. Server operators have asked for this one specifically because getting a client's Steam ID can be difficult if authentication takes a while.
It can be found here: https://github.com/SamVanheer/HLEnhanced/blob/iface_proposal/shared/game/server/IServerGameLib.h
Should the documentation not adequately cover when callbacks should be invoked, i can with reasonable accuracy give you the function and location in that function to invoke them based on reverse engineered information.
I will be writing a version for the client side tomorrow to cover some things that are missing on that side, and probably refactor this code to deal with common issues.