Set up a UE4 project to use SkookumScript

In order to run SkookumScript code as part of your project, the project must first be set up to use SkookumScript. We call this Skookifying a project.

Skookify your project

1. At the bottom of the Members widget, click the collapsed New Class or Member pane. A “Skookify your project?” confirmation message will display:

“Skookify your project?” confirmation message.

2. Click Yes to add the files SkookumScript needs to your project. (See Skookification: What happens under the hood below.)

3. If you are using a version control system such as Perforce, you will need to start tracking the project by adding the new Scripts folder and all its subfolders and files. (You do not have to add the Content\SkookumScript folder or files, since they are generated by the SkookumIDE.)

Congratulations, your project is now Skookified! You can now add snazzy SkookumScript code via the New Class or Member pane.

Skookification: What happens under the hood

When you Skookify your UE4 project, this is what happens:

• a Scripts folder is created, which contains a Skookum-project.ini project settings file that details all the overlays for the project
• a Project subfolder is created—this will contain SkookumScript code in the Project overlay
• compiled script binaries are placed in the Content\SkookumScript folder
• the SkookumScript UE4 Plugin is notified about Skookifying the project (which obviously requires the SkookumIDE be connected to the UE4 editor) and it does the following additional actions:
  • the project-specific Blueprints and C++ script bindings (those reflected to Blueprints) are analysed and the corresponding SkookumScript overlays and scripts are generated including the subfolders Project-Generated-BP and Project-Generated-C++
  • DefaultGame.ini is modified to include the SkookumScript compiled binaries in the cooked project data. If DefaultGame.ini is checked into version control, it will first be checked out.

Resolving name collisions: UE4 Blueprint and reflected C++ renaming system for generated SkookumScript

A class/struct/enum and property renaming system exists to resolve name collisions during the generation of SkookumScript code from UE4 Blueprints and reflected C++. Skookification of all class/struct/enum and data member names gets routed through the renaming system.

To use it, add entries to your project’s Config/SkookumScript.ini file.

Use the +RenameClasses key to specify a rename rule for a class/struct/enum in the format:

[package_name.]UE4TypeName->SkookumScriptClassName

Use the +RenameProperties key to specify a rename rule for a property/data member in the format:

[[package_name.]owner_name.]UE4PropertyName->@skookumscript_data_member_name

You can also use the package name (asset path) to resolve name clashes between assets with the same name located in different folders. The generic syntax is:

+RenameClasses=[/Path/To/AssetPackage.]UE4ClassOrStructOrEnumName->SkookumScriptClassName
+RenameProperties=[[/Path/To/AssetPackage.]UE4ClassOrStructName.]UE4PropertyName->@skookumscript_data_member_name

For example:

+RenameProperties=Hero.My Best Enemy->@my_nicest_enemy
+RenameClasses=Hero->Protagonist
+RenameClasses=/Game/MyBPStruct.MyBPStruct->MyBPStruct2

When you make changes to the SkookumScript.ini file, and change focus back to UE4 editor, the SkookumScript.ini file gets reloaded by the SkookumScript plugin and script files are regenerated based on the changes - then changing focus to the SkookumIDE and compiling applies the changes to the compiled SkookumScript binaries.

SkookumScript and non-SkookumScript projects: feature comparison

With both SkookumScript-enabled and non-SkookumScript projects, code snippets can be executed from the SkookumIDE Workbench (REPL) widgets using common engine commands. However, only SkookumSript-enabled projects can create project-specific SkookumScript commands. Likewise, only SkookumScript-enabled projects can call project-specific SkookumScript commands or project-specific C++-reflected commands.

Related: Disable or remove SkookumScript in a UE4 project

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