merge index and introduction

docs/Modding/plugins/index.md

@@ -1,7 +1,75 @@
 # Plugins
 
+!!! note
+
+    Writing plugins require some very basic familiarity with C++
+
+
 Plugins are native modules loaded by Northstar. Because they're not limited to any API provided by the game, plugins are a powerful tool to enable you to do almost anything you could with a custom Northstar Client.
 
 For example, you could write a plugin that [compiles maps](https://github.com/catornot/furnace) at runtime, allows squirrel scripts to save and load recorded animations [from disk](https://github.com/uniboi/recanim) or provide [discord rpc](https://github.com/R2Northstar/NorthstarDiscordRPC) integration.
 
-However because plugins have full access to your system plugins should be treated with caution and regular scripts are preferred if possible.
+However because plugins have full access to your system plugins should be treated with caution and regular scripts are preferred if possible.
+
+## Installation
+
+Any `.dll` file located in the directories `<Northstar Profile>/plugins/` and `<Northstar Profile>/packages/<Thunderstore package>/plugins/` will be attempted to load as a plugin.
+
+To manually install a plugin, copy the plugin `.dll` into the `<Northstar Profile>/plugins/` directory.
+
+!!! note
+
+    The default northstar profile name is `R2Northstar`. Profiles are located in the same location as `NorthstarLauncher.exe`.
+
+
+Any Plugin is only valid if it exposes every required [interface](interfaces.md).
+
+If a plugin does not expose every Interface the Launcher requires, it is unloaded immediately.
+
+## Development
+
+To debug a plugin it's recommended to compile Northstar itself or download the debug data from the [Release Page](https://github.com/R2Northstar/NorthstarLauncher/releases).
+
+When developing a plugin it's usually easier to output the binary directly in the `<profile>/plugins/` directory, the `packages/` directory is usually only used for complete packaged mods downloaded from Thunderstore.
+
+### Valid plugins
+
+Every plugin must fulfill these criteria to be considered valid by Northstar.
+
+Invalid plugins get unloaded as soon as possible.
+
+- The plugin module must export a function named [`CreateInterface`](interfaces.md/#createinterface) that returns an interface instance when called.
+
+- Every [required interface](required-interfaces.md) must be exposed via `CreateInterface`
+
+### Debugging
+
+If you know how to use a debugger you can safely skip this.
+
+For simplicity it's assumed your development environment is Visual Studio and you're compiling Northstar from source.
+
+Otherwise are the steps basically the same everywhere else.
+
+1. Clone the [Launcher](https://github.com/R2Northstar/NorthstarLauncher)
+
+2. Set the binary output directory to the location wherever you have installed your game. The compiled `NorthstarLauncher.exe` should be outputted next to `Titanfall.exe`.
+
+3. Launch `NorthstarLauncher.exe` with a debugger or attach a debugger to a running process
+
+4. Load debug symbols of your plugin(s) (`myplugin.pdb`) in the debugger
+
+That's it.
+
+### Hooks
+
+Any Plugin can install hooks anywhere in memory it desires. However, plugins should avoid hooks if possible because of conflicts with Northstar itself or hooks installed by other plugins.
+
+It is not generically possible to determine if a given address has already been hooked by a different plugin and there is currently **no mechanism for plugins to share information which addresses have hooks installed**.
+
+Northstar does not expose an interface to (un)install hooks. Every plugin is expected to use their own provider.
+
+## Examples and Libraries
+
+- A small plugin [""framework""](https://github.com/uniboi/NSPluginTemplate/) to show the basics of writing plugins and Squirrel bindings in C
+
+- A complete [Rust plugin library](https://crates.io/crates/rrplug) that allows you to easily integrate safely with large parts of the engine itself