Files
gregWiki/docs/guides/mod-developers/greg-hooks-showcase.md
Marvin ee3f30e502 docs: update sidebar and documentation to include greg hooks registry
- Added new items to the sidebar for 'greg-hooks-and-events' and 'greg-hooks-registry' under the Framework and Reference categories, respectively.
- Enhanced the documentation layout by including references to the greg hooks registry in various guides and topics, improving accessibility to hook-related information.
- Updated descriptions in the documentation to clarify the purpose and usage of the greg hooks and their registry.

This commit aims to improve the visibility and usability of the greg hooks registry within the documentation.
2026-04-10 03:36:30 +02:00

3.2 KiB

title, sidebar_label, description
title sidebar_label description
Greg hooks showcase (sample mod) Greg hooks showcase Subscribe to greg.* hooks via GregShowcaseMod, GregEventDispatcher, GregPayload, and optional OnCancelable veto.

Greg hooks showcase

The gregFramework repo ships GregShowcaseMod at mods/GregShowcaseMod/. It demonstrates the public API only:

  • GregEventDispatcher.On / Once / OnCancelable / UnregisterAll
  • GregHookName.Create(GregDomain.*, "Action")
  • GregPayload.Get<T> / GregPayload.Dump for anonymous payloads

Canonical hook strings

Runtime names look like greg.<DOMAIN>.<Action>. Always build them with GregHookName.Create — do not concatenate raw strings in mods.

Registry

greg_hooks.json at the gregFramework repository root is the canonical catalog (description, payloadSchema, strategy, optional legacy). A copy is emitted next to FrikaModdingFramework.dll for GregCompatBridge legacy resolution.

Authoritative documentation: greg hooks registry (IL2CPP) — regeneration script, whitelist, and Harmony deduplication rules.

FFI bridge and greg.* emission

DataCenterModLoader.EventDispatcher emits greg.* events through GregHookIntegration for the same gameplay moments as the Rust FFI event ids (money, cables, customers, save/load, etc.), even when the FFI bridge is not connected.

Payload access patterns

Pattern A — dynamic (anonymous types from compiler):

private static void OnMoneyChanged(object payload)
{
    dynamic p = payload;
    float delta = (float)p.coinChangeAmount;
    float balance = (float)p.newBalance;
    MelonLogger.Msg($"Δ={delta} → {balance}");
}

Pattern B — GregPayload (reflection, case-insensitive property names):

private static void OnReputationChanged(object payload)
{
    var amount = GregPayload.Get<float>(payload, "amount");
    var rep = GregPayload.Get<float>(payload, "reputation");
    MelonLogger.Msg($"Reputation: {amount} → {rep}");
}

Pattern C — typed record (when you define a shared contract in your mod or core):

// public record PlayerMoneyPayload(float CoinChangeAmount, float NewBalance, bool WithoutSound, bool Accepted);
// if (payload is PlayerMoneyPayload p) { ... }

Use GregPayload.Dump(payload) for one-line debug strings.

Prefix hooks and cancellation

Hooks that run before the original method (Harmony Prefix) can call GregEventDispatcher.InvokeCancelable(hookName, payload). Mods register GregEventDispatcher.OnCancelable(hookName, p => bool, modId); if any handler returns false, the integration can skip the original (e.g. Player.UpdateCoin).

Showcase: enable blockNegativeTransactions in content/modconfig.json to register a veto on large negative coinChangeAmount values.

Configuration

Edit content/modconfig.json next to the built DLL (defaults are copied from the repo). Keys include logPlayerEvents, logNetworkEvents, blockNegativeTransactions, reputationWarningThreshold.

See also