Getting started with SlugBase!

Prerequisite

This guide assumes that you already know how to make Rain World mods. If that isn't the case, see the SlugTemplate Walkthrough to build a mod from the ground up.

Custom Slugcats

To create a simple SlugBase slugcat, start by making a file called slugbase\scholar.json. The name of this file isn't crucial and won't break if other mods name theirs the same. The contents must be a JSON object with at least the "id", "name", and "description" properties:

{
  "id": "Scholar",
  "name": "The Scholar",
  "description": "This is the description of The Scholar, and will appear on the main menu.<LINE>This will appear on line 2."
}
  • "id": A unique ID that isn't displayed to the user. Your mod will fail to load if another character has this ID!
  • "name": The display name of this character.
  • "description": The description of this character on the character select menu.
  • "features": An optional list of settings, abilities, or other features of this character or its save slot.

This will create a copy of Survivor called "The Scholar". That's not very interesting on its own; that's where features come in!

{
  "id": "Scholar",
  ...
  "features": {
    "color": "9530A1",
    "custom_colors": [
      { "name": "Body", "story": "9530A1" },
      { "name": "Eyes", "story": "FFFFFF" }
    ],
    "start_room": "SI_S04",
    "select_menu_scene": "Slugcat_Scholar"
  }
}

Now the Scholar is purple with white eyes, starts in Sky Islands, and will use the "Slugcat_Scholar" scene in the character select menu. See Built-In Features for a list of features you can use here. Most characters will need some new mechanics to set them apart from other campaigns. To implement those, see Custom Features.

Some features, such as color or stats, might take some iteration to get right. With SlugBase 2, you don't have to compile your mod and restart the game to make these changes; just edit the JSON file and they will apply immediately! This won't work with features that are only checked occasionally, such as "karma" or "start_room".

The Scholar will work as it is, but its character select scene will be blank. We need some sort of system for...

Custom Scenes

Custom scenes are made in a similar way to custom characters. To get started, you make a file called slugbase\scenes\slugcat_scholar.json. Again, the file name does not need to be unique. The JSON object needs at least the "id", "images", and "idle_depths" properties:

{
  "id": "Slugcat_Scholar",
  "scene_folder": "slugbase/scenes/slugcat_scholar",
  "images": [
    {"name": "flat",       "pos": [  0,   0], "depth": -1.0, "flatmode": true},
    {"name": "background", "pos": [442, 134], "depth":  3.5},
    {"name": "scholar",    "pos": [516, 185], "depth":  2.8, "shader": "Basic"},
    {"name": "foreground", "pos": [301,  18], "depth":  1.5}
  ],
  "idle_depths": [2.3, 2.9],
  "glow_pos": [730, 335],
  "mark_pos": [740, 575],
  "select_menu_pos": [-10, 100],
  "slugcat_depth": 2.8
}
  • "id": A unique ID. Your scene will fail to load if another scene has this ID!
  • "scene_folder": An optional path to the folder containing scene images. This is relative to StreamingAssets or your mod's folder, and defaults to illustrations.
  • "images": A list of image objects that make up this scene.
    • "name": A file name to append to "scene_folder" when loading this image, excluding the file extension.
    • "pos": The position of this image's bottom left corner relative to the bottom left of the screen. For an image of size 1366x768 this should be [0,0] to display in the center of the screen.
    • "depth": The depth of this object in the scene. This only determines how it will be blurred and how parallax will be applied. Layering follows the order specified, with earlier images being layered below later ones.
    • "shader": The shader to use when drawing this image. This may be "Normal", "Lighten", "LightEdges", "Rain", "Overlay", "Basic", "SoftLight", or "Multiply".
  • "idle_depths": A list of depths for the camera to focus on. The actual focus depth may be up to 0.5 greater than this. The focus depth will also disregard these values while the mouse is in motion. If you need an image to not be blurry, change "shader" to "Basic" and remove its depth map.

A few optional properties are specific to the character select menu:

  • "glow_pos": The position of the glow's center. This is typically centered on the character.
  • "mark_pos": The position of the mark's center. This is typically above the character's head.
  • "select_menu_pos": The offset of this scene when displayed in the select menu.
  • "slugcat_depth": The depth of the slugcat image in this scene. This is used to apply parallax to the mark and glow.
  • "dream_override": If this scene is used as a dream, should it override Moon and Pebble dreams being set.

Hmmm, but wouldn't it be cool if we could also have an intro slideshow like Survivor or Gourmand...

Custom Slideshows

Much the same way you created your Character Select Menu, create a file called slugbase\slideshows\slugecat_scholar.json. The file name also does not need to be unique. The JSON object needs at least the "id", "next_process", "scenes" properties. Each entry in the "scenes" property requires "name" and "images", and functions identically to the above custom scene object:

{
  "id": "Scholar_Intro",
  "slideshow_folder": "slugbase/slideshows/scholar_intro",
  "next_process": "Game",
  "music": {
    "name": "RW_Intro_Theme",
    "fade_in": 40
  },
  "scenes": [
    {
      "name": "scene1",
      "fade_in_start": 0,
      "fade_out_start": 7.1,
      "images": [
        {"name": "background1", "pos": [0,0], "depth": -1, "shader": "Basic"},
        {"name": "scholar1",    "pos": [0,0], "depth": 1.5}
      ],
      "camera_path": [ [10, 15, 0], [8.7, 5, 0.5] ]
    },
    {
      "name": "scene2",
      "fade_in_start": 8.1,
      "fade_in_end": 11.25,
      "fade_out_start": 17,
      "images": [
        {"name": "background2", "pos": [0,   0], "depth": -1,    "shader": "Basic"},
        {"name": "background3", "pos": [100,65], "depth": 4.15, "shader": "Basic"},
        {"name": "scholar2",    "pos": [10, 10], "depth": 1,    "shader": "Basic"}
      ],
      "movements": [ [-10,-25], [-2.5,4], [-3,7] ]
    }
  ]
}
  • "id": A unique ID. Your slideshow may fail to load if another slideshow has this ID!
  • "slideshow_folder": An optional path to the folder containing slideshow images. This is relative to StreamingAssets or your mod's folder, and defaults to illustrations.
  • "next_process": The process to go to when this slideshow is done playing. Common options will be Game for intro slideshows, and Credits or Statistics for outros.
  • "music": Play some music during your slideshow! If unspecified this defaults to silence.
    • "name": The name of the music to play. This should exactly match the name of one of the mp3 files in StreamingAssets\music\songs, excluding the file extension. Custom songs can be added by placing the mp3 file in mymod\music\songs\.
    • "fade_in": The time in seconds that the music takes to fully fade in. If unspecified this defaults to 40.
  • "scenes": Groups of images to display and when to display them.
    • "name": The scene's ID. This only needs to be unique in relation to other scenes in this slideshow's JSON.
    • "scene_folder": An optional path to the folder containing scene images. This is relative to StreamingAssets or your mod's folder, defaults to illustrations, and takes precedence over "slideshow_folder".
    • "fade_in_start": The time in seconds for the scene's images to start fading in.
    • "fade_in_end": The time in seconds when the scene's images finish their fade in animation. If unspecified this defaults to 1 second after the fade starts.
    • "fade_out_start": The time in seconds when the scene's images begin to fade out.
    • "images": The images to use in this scene, all displayed at once, with those in the list first being placed behind those later in the list.
      • "name": A file name to append to "scene_folder" or "slideshow_folder" when loading this image, excluding the file extension.
      • "pos": The position of this image's bottom left corner relative to the bottom left of the screen. For an image of size 1366x768 this should be [0,0] to display in the center of the screen.
      • "depth": The depth of this object in the scene. This only determines how it will be blurred and how parallax will be applied. Layering follows the order specified, with earlier images being layered below later ones.
      • "shader": The shader to use when drawing this image. This may be "Normal", "Lighten", "LightEdges", "Rain", "Overlay", "Basic", "SoftLight", or "Multiply".
    • "camera_path": An optional list of points for the camera to move along when displaying this scene. The first two elements of each point represent the camera position, and the optional third element represents the focal depth between 0 and 1.

Slideshows can be used for intros via the "intro_slideshow" feature, and outros when finishing the game via the "outro_slideshow" feature. You can start a slideshow manually by setting processManager.nextSlideshow and calling processManager.RequestMainProcessSwitch(ProcessManager.ProcessID.SlideShow).