Add NamePlateGui

Dalamud/Plugin/Services/INamePlateGui.cs

@@ -0,0 +1,37 @@
+using System.Collections.Generic;
+
+using Dalamud.Game.Gui.NamePlate;
+
+namespace Dalamud.Plugin.Services;
+
+/// <summary>
+/// Class used to modify the data used when rendering nameplates.
+/// </summary>
+public interface INamePlateGui
+{
+    /// <summary>
+    /// The delegate used for receiving nameplate update events.
+    /// </summary>
+    /// <param name="context">An object containing information about the pending data update.</param>
+    /// <param name="handlers>">A list of handlers used for updating nameplate data.</param>
+    public delegate void OnPlateUpdateDelegate(
+        INamePlateUpdateContext context, IReadOnlyList<INamePlateUpdateHandler> handlers);
+
+    /// <summary>
+    /// An event which fires when nameplate data is updated and at least one nameplate has important updates. The
+    /// subscriber is provided with a list of handlers for nameplates with important updates.
+    /// </summary>
+    event OnPlateUpdateDelegate? OnNamePlateUpdate;
+
+    /// <summary>
+    /// An event which fires when nameplate data is updated. The subscriber is provided with a list of handlers for all
+    /// nameplates. This event is likely to fire every frame even when no nameplates are actually updated, so in most
+    /// cases <see cref="OnNamePlateUpdate"/> is preferred.
+    /// </summary>
+    event OnPlateUpdateDelegate? OnDataUpdate;
+
+    /// <summary>
+    /// Requests that all nameplates should be redrawn on the following frame.
+    /// </summary>
+    void RequestRedraw();
+}