Statically linking plugins to a game project

[chaosgrid]

Is there a best practice or tutorial for this?

In the plugin documentation, it says:

Most plugin modules have no business exporting public APIs in header files in a Public source folder, because they will never be a direct dependency (statically linked against) by engine or game code. There are a few exceptions to this rule:

• If you are creating a game plugin (not engine plugin), and you want to allow the game to statically link against one of your plugin modules. This breaks the concept of a plugin a little bit, but is often useful for plugins that want to declare new UObject types that game classes can inherit from or use directly. The engine itself has no dependencies on this plugin, but the game project code and content may very well have direct dependencies.

However, in this discussion, it has been thoroughly discouraged to do just that:

Cannot find DLL when using an UObject exported via plugin from game module code

You have two options:

• Convert your plug-in module to a true plug-in and remove the game’s dependency to this module. Your game should provide some abstract API (through interface classes) that your plug-in module can implement. UdpMessaging is an example for a plug-in module that extends an existing API (the Messaging API).

• Convert your plug-in module to a library module and make it not a plug-in. The module’s code should be located inside your game’s Source directory. Your game can retain the hard dependency to this module. When your module gets compiled as a DLL, it will automatically be located in your game’s Binaries directory. Note that your game can have any number of modules. Check out the ShooterGame sample game, for example.

So, for my current project, I went the route of just putting it in the game code, however, the question still stands - who is correct and what is the best way to statically link a plugin to a game?

I think there is a valid use case, for example specific applications that all rely on a certain input tracker device or whatever. Or the other example, where you define new UObjects, to be used in many applications. Why would you copy/paste the module in all those different game projects instead of just referencing a statically linked plugin?

The reason Im asking if there is a best practice or if it is downright forbidden, is because I tried to statically link my plugin but I ran in the problem of the UE Editor having to load my plugin and being unable to load it from the plugin’s directory. Is this a bug or intentional?

Also related: How do I Statically link a plugin to my game code - Plugins - Epic Developer Community Forums

[getnamo]

Unless I misunderstand, all of my input plugins currently do this by exposing custom UObjects that get emitted from each controller event. If you use these plugin classes and then remove the plugins, on restart, the blueprints will generally remove the links to the objects with warnings.

Have a look at their source to see if this isn’t what you’re trying to do.

[chaosgrid]

@getnamo;184530

Unless I misunderstand, all of my input plugins currently do this by exposing custom UObjects that get emitted from each controller event. If you use these plugin classes and then remove the plugins, on restart, the blueprints will generally remove the links to the objects with warnings.

Have a look at their source to see if this isn’t what you’re trying to do.

Oh yeah, I’m not talking about Blueprints because as discussed in the first link, they only get evaluated at runtime and so can dynamically reference plugins.

I’m talking about statically linking to a plugin from within C++ code.

[getnamo]

@chaosgrid;184658

Oh yeah, I’m not talking about Blueprints because as discussed in the first link, they only get evaluated at runtime and so can dynamically reference plugins.

I’m talking about statically linking to a plugin from within C++ code.

The plugins support C++ binds as well, you can reference them within your C++ code with the right header after including the plugin module in your project build rules. This is shown in the razer hydra video near then end.

[chaosgrid]

@getnamo;184757

The plugins support C++ binds as well, you can reference them within your C++ code with the right header after including the plugin module in your project build rules. This is shown in the razer hydra video near then end.

Ah cool, just saw it! Great plugin by the way.

Guess I’ll have to compare and see what went wrong on my end…

[anonymous_user_0dc1700e]

What I would like to know is HOW you “hard link” vs “static” or “dyanmic” or “monolitic” link. The docs just mention the linkage type but don’t mention how to do any of them.