Platform Chat

Built-in text chat for multiplayer games. Messages are routed through the host, validated, filtered, and displayed via the standard overlay UI - no game code required.

The API lives in the Sandbox.Platform namespace.

Project Settings

Chat can be configured in Project Settings > Platform:

• Chat Enabled - toggle the entire chat system on or off
• Show Chat UI - hide the built-in overlay while still processing messages and firing events (useful for custom chat UIs)
• Max Message Length - cap message length (up to 256 characters)

Sending Messages

Chat.Say( string message )

Send a chat message to the server. The host validates and broadcasts it to all connected players.

Chat.Say( "Hello everyone!" );

Chat.AddText( string message )

Add a local-only notification to the chat feed. Not networked.

Chat.AddText( $"{player.Name} joined the game" );

:::info Messages are automatically sanitized, rate-limited, and passed through Steam's text filter. Blocked users are filtered out on the receiving end. :::

Scene Events

Implement IChatEvent on a component to intercept, modify, suppress, or filter messages. This event fires in two places:

• On the host - before broadcasting. You can modify the message, suppress it, or set a RecipientFilter.
• On receiving clients - after delivery. You can still suppress the message to prevent it from showing in the UI.

public class TeamChat : Component, IChatEvent
{
    public void OnChatMessage( ChatMessageEvent e )
    {
        if ( !e.Message.StartsWith( "/team" ) )
            return;

        // Strip the command prefix
        e.Message = e.Message["/team ".Length..];

        // Only deliver to players on the same team
        var senderTeam = GetTeam( e.Sender );
        e.RecipientFilter = connection => GetTeam( connection ) == senderTeam;
    }
}

ChatMessageEvent