Everest Events

Everest provides a number of events that can be subscribed to from within your code mod. This guide lists each event, the methods within Celeste that raise it, and any additional notes on it.

To subscribe to an event, use the following format:

Everest.Events.Level.OnLoadLevel += Your_OnLoadLevel_Method;

where Your_OnLoadLevel_Method is a method with arguments matching those listed in this guide:

private void Your_OnLoadLevel_Method(Level level, Player.IntroTypes playerIntro, bool isFromLoader){

}

Event Types

Celeste
Main Menu
Level
LevelLoader
Player
Input
Journal
Decal
FileSelectSlot
EventTrigger
CustomBirdTutorial

Events

Celeste

Event	Raised By	Notes
`OnExiting`()	Celeste.Celeste.OnExiting	Called after the main gameloop has finished running in Microsoft.Xna.Framework.Game.Run
`OnShutdown`()	Celeste.Celeste.Main	Called just before the Main method exits

Everest

Event	Raised By	Notes
`OnLoadMod`(EverestModuleMetadata meta)	‎Everest.Loader.LoadMod	Called when a mod finishes loading.
`OnRegisterModule`(EverestModule module)	Everest.Register	Called when a mod is registered.

MainMenu

Event	Raised By	Notes
`OnCreateButtons`(OuiMainMenu menu, List buttons)	Celeste.OuiMainMenu.Added Celeste.OuiMainMenu.RebuildMainAndTitle Celeste.Settings.Reload	Used for adding new MenuButtons to the OuiMainMenu Ex: Everest.CoreModule 🔗

LevelLoader

Event	Raised By	Notes
`OnLoadingThread`(Level level)	Celeste.LevelLoader.LoadingThread

Level

Event	Raised By	Notes
`OnPause`(Level level, int startIndex, bool minimal, bool quickReset)	Celeste.Level.Pause
`OnCreatePauseMenuButtons`(Level level, TextMenu menu, bool minimal)	Celeste.Level.Pause
`OnUnpause`(Level level)	Celeste.Level.Pause
`OnTransitionTo`(Level level, LevelData next, Vector2 direction)	Celeste.Level.TransitionTo
`OnLoadEntity`(Level level, LevelData levelData, Vector2 offset, EntityData entityData)	Celeste.Level.LoadCustomEntity
`OnLoadBackdrop`(MapData map, BinaryPacker.Element child, BinaryPacker.Element above)	Celeste.Mapdata.LoadCustomBackdrop
`OnLoadLevel`(Level level, Player.IntroTypes playerIntro, bool isFromLoader)	Celeste.Level.LoadLevel
`OnEnter`(Session session, bool fromSaveData)	Celeste.LevelEnter.Go	As of Everest 1436, is called on ctrl+f5
`OnExit`(Level level, LevelExit exit, LevelExit.Mode mode, Session session, HiresSnow snow)	Celeste.LevelExit.LevelExit
`OnComplete`(Level level)	Celeste.Level.RegisterAreaComplete

Player

Event	Raised By	Notes
`OnSpawn`(Player player)	Celeste.Player.Added
`OnDie`(Player player)	Celeste.Player.Die
`OnRegisterStates`(Player player)	Celeste.Player.PostCtor

Seeker

Event	Raised By	Notes
`OnRegisterStates`(Seeker seeker)	Celeste.Seeker constructor

AngryOshiro

Event	Raised By	Notes
`OnRegisterStates`(AngryOshiro oshiro)	Celeste.AngryOshiro constructor

Input

Event	Raised By	Notes
`OnInitialize`	Celeste.Input.Initialize
`OnDeregister`	Celeste.Input.Deregister

Journal

Event	Raised By	Notes
`OnEnter`(OuiJournal journal, Oui from)	Celeste.OuiJournal.Enter

Decal

Event	Raised By	Notes
`OnHandleDecalRegistry`(Decal decal, DecalRegistry.DecalInfo decalInfo)	Celeste.Decal.Added

FileSelectSlot

Event	Raised By	Notes
`OnCreateButtons`(List<OuiFileSelectSlot.Button> buttons, OuiFileSelectSlot slot, EverestModuleSaveData modSaveData, bool fileExists)	Celeste.OuiFileSelectSlot.CreateButtons	Added in Everest 1459

Usage example:

// event registering (in the Load() method for example)
Everest.Events.FileSelectSlot.OnCreateButtons += addSilhouetteButton;

private void addSilhouetteButton(List<OuiFileSelectSlot.Button> buttons, OuiFileSelectSlot slot, EverestModuleSaveData saveData, bool fileExists) {
  // add a simple toggle button for an option in mod save data (SilhouetteEnabled)
  OuiFileSelectSlot.Button button = new OuiFileSelectSlot.Button {
    Label = $"Silhouette Mode: {(saveData as MyModuleSaveData).SilhouetteEnabled}",
    Scale = 0.7f
  };
  button.Action = () => {
    (saveData as MyModuleSaveData).SilhouetteEnabled = !(saveData as MyModuleSaveData).SilhouetteEnabled;
    button.Label = $"Silhouette Mode: {(saveData as MyModuleSaveData).SilhouetteEnabled}";
  };
  buttons.Add(button);

  // add a button opening a OuiFileSelectSlotSubmenu
  buttons.Add(new OuiFileSelectSlot.Button {
    Label = $"Silhouette Mode Options",
    Scale = 0.7f,
    Action = () => OuiFileSelectSlotSubmenu.Goto<OuiSilhouetteModeOptions>(slot, saveData, fileExists)
  });
}

Submenu implementation example:

using Celeste.Mod.UI;

namespace Celeste.Mod.MyMod {
  class OuiSilhouetteModeOptions : OuiFileSelectSlotSubmenu {
    public override string MenuName => "SILHOUETTE MODE OPTIONS";

    protected override void addOptionsToMenu(TextMenu menu, OuiFileSelectSlot slot, EverestModuleSaveData modSaveData, bool fileExists) {
      MyModuleSaveDatacastSaveData = (modSaveData as MyModuleSaveData);

      menu.Add(new TextMenu.SubHeader("Toggle"));
      menu.Add(new TextMenu.OnOff("Enabled", castSaveData.SilhouetteEnabled).Change(newValue => castSaveData.SilhouetteEnabled = newValue));
    }
  }
}

EventTrigger

Event	Raised By	Notes
`OnEventTrigger`(EventTrigger trigger, Player player, string eventID)	EventTrigger.OnEnter	Added in Everest 1767

CustomBirdTutorial

Event	Raised By	Notes
`onParseCommand`(string command)	CustomBirdTutorial constructor	Added in Everest 1925

Usage example:

Everest.Events.CustomBirdTutorial.OnParseCommand += onParseCommand;

private object OnParseCommand(string command) {
    // this method can return:
    // - a MTexture => displays that texture
    if (command == "StrawberryIcon") {
        return GFX.Gui["collectables/strawberry"];
    }
    // - a Vector2 representing a direction (x, y) => displays an arrow
    if (command == "DownLeft") {
        return new Vector2(-1, 1);
    }
    // - a ButtonBinding or VirtualButton => displays the button it is set to (useful for custom bindings)
    if (command == "RandomBinding") {
        return (_Settings as MaxHelpingHandModuleSettings).RandomBinding;
    }
    // - a string => displays that text
    if (command == "SayHi") {
        return "Hi!";
    }
    // if your mod doesn't recognize the command, return null to let other mods / Everest handle it instead.
    return null;
}

AssetReload

Event	Raised By	Notes
`OnBeforeReload`(bool silent)	Everest.AssetReloadHelper.Do
`OnAfterReload`(bool silent)	Everest.AssetReloadHelper.Do
`OnReloadLevel`(Level level)	Everest.AssetReloadHelper.ReloadLevel
`OnReloadAllMaps`(Level level)	Everest.AssetReloadHelper.ReloadAllMaps