Add "Hidden icons" rules, applied at draw time

MapIconsSettings.cs

@@ -2,9 +2,60 @@
 using ExileCore.Shared.Interfaces;
 using ExileCore.Shared.Nodes;
 using MinimapIcons.IconsBuilder;
+using System;
 
 namespace MinimapIcons;
 
+/// <summary>
+/// One "never draw an icon for this" entry, editable from the plugin menu.
+/// </summary>
+/// <remarks>
+/// The existing ignore mechanisms are both applied when the icon is *built*: entries in
+/// <c>ignored_entities.txt</c> and in <see cref="MinimapIcons.Ignored"/> make
+/// <c>IconsBuilder.SkipIcon</c> return before an icon object exists. That is fine for a
+/// permanent exclusion, but it means an entry cannot be undone without an area change, and
+/// the hardcoded list cannot be undone at all. These rules are applied at draw time instead,
+/// so toggling one takes effect on the next frame in both directions.
+/// </remarks>
+[Submenu]
+public class IconIgnoreRule
+{
+    public IconIgnoreRule()
+    {
+    }
+
+    public IconIgnoreRule(string label, string metadataRegex, bool hide)
+    {
+        Label = new TextNode(label);
+        MetadataRegex = new TextNode(metadataRegex);
+        Hide = new ToggleNode(hide);
+    }
+
+    [Menu("Hide", "On = matching entities get no icon. Off = they draw as normal.")]
+    public ToggleNode Hide { get; set; } = new ToggleNode(true);
+
+    [Menu("Label", "Free text, so the row is recognisable in this list. Not used for matching.")]
+    public TextNode Label { get; set; } = new TextNode("");
+
+    [Menu("Metadata regex", "Unanchored regex tested against the entity metadata path.")]
+    public TextNode MetadataRegex { get; set; } = new TextNode("");
+
+    // Names the row in the settings UI, which otherwise falls back to object.ToString() and shows
+    // every row as "MinimapIcons.IconIgnoreRule". The trailing ### keeps the ImGui id of the row
+    // stable while the visible part of the label changes, so the row does not collapse itself
+    // while you are typing in the label or pattern field.
+    public override string ToString()
+    {
+        var label = !string.IsNullOrWhiteSpace(Label?.Value)
+            ? Label.Value
+            : !string.IsNullOrWhiteSpace(MetadataRegex?.Value)
+                ? MetadataRegex.Value
+                : "(empty rule)";
+
+        return $"{label}###";
+    }
+}
+
 public class MapIconsSettings : ISettings
 {
     public ToggleNode DrawMonsters { get; set; } = new ToggleNode(true);
@@ -21,6 +72,23 @@ public class MapIconsSettings : ISettings
     public RangeNode<int> IconListRefreshPeriod { get; set; } = new RangeNode<int>(100, 0, 1000);
     public ToggleNode HighlightHiddenMonsters { get; set; } = new ToggleNode(true);
 
+    [Menu("Hidden icons", "Entities you never want an icon for, each with its own on/off. Unlike " +
+                          "ignored_entities.txt these are applied at draw time, so a toggle takes effect " +
+                          "immediately and can be undone without changing areas. Empty by default.",
+        CollapsedByDefault = true)]
+    public ContentNode<IconIgnoreRule> HiddenIcons { get; set; } =
+        new ContentNode<IconIgnoreRule>()
+        {
+            Content =
+            [
+            ],
+            EnableControls = true,
+            EnableItemCollapsing = true,
+            ItemFactory = () => new IconIgnoreRule(),
+            ItemFilter = (o, s) => o.Label.Value.Contains(s, StringComparison.OrdinalIgnoreCase) ||
+                                   o.MetadataRegex.Value.Contains(s, StringComparison.OrdinalIgnoreCase),
+        };
+
     [Menu(null, CollapsedByDefault = true)]
     public ContentNode<TextNode> AlwaysShownIngameIcons { get; set; } =
         new ContentNode<TextNode>()

MinimapIcons.cs

@@ -11,6 +11,7 @@
 using System.Collections.Generic;
 using System.Drawing;
 using System.Linq;
+using System.Text.RegularExpressions;
 using Color = SharpDX.Color;
 using RectangleF = SharpDX.RectangleF;
 using Vector2 = System.Numerics.Vector2;
@@ -158,6 +159,18 @@ public class MinimapIcons : BaseSettingsPlugin<MapIconsSettings>
 
     private readonly Dictionary<string, bool> IgnoreCache = new Dictionary<string, bool>();
 
+    // Compiled regexes for Settings.HiddenIcons keyed by pattern text, plus the per-path answers
+    // derived from them. A breach puts hundreds of icons behind a handful of distinct paths, so
+    // this turns the regex work into a dictionary hit after the first sighting of each path.
+    private readonly Dictionary<string, Regex> _hiddenIconRegexes = new(StringComparer.Ordinal);
+    private readonly HashSet<string> _badHiddenIconPatterns = new(StringComparer.Ordinal);
+    private readonly Dictionary<string, bool> _hiddenIconCache = new(StringComparer.Ordinal);
+
+    // Cheap hash of the rule set, so an edit in the menu invalidates the cache above. Recomputed
+    // once per frame rather than per icon, and an int rather than a joined string, because
+    // Render() runs every frame and should not allocate.
+    private int _hiddenIconSignature;
+
     private IngameUIElements _ingameUi;
     private bool? _largeMap;
     private float _mapScale;
@@ -257,6 +270,8 @@ public override void Render()
         var baseIcons = _iconListCache.Value;
         if (baseIcons == null) return;
 
+        RefreshHiddenIconRules();
+
         foreach (var icon in baseIcons)
         {
             if (icon?.Entity == null) continue;
@@ -267,6 +282,9 @@ public override void Render()
             if (IgnoreCache.GetOrAdd(icon.Entity.Path, () => Ignored.Any(x => icon.Entity.Path.StartsWith(x))))
                 continue;
 
+            if (IsHiddenByRule(icon.Entity.Path))
+                continue;
+
             if (icon.Entity.Path.StartsWith(
                     "Metadata/Monsters/AtlasExiles/BasiliskInfluenceMonsters/BasiliskBurrowingViper", StringComparison.Ordinal)
                 && icon.Entity.Rarity != MonsterRarity.Unique)
@@ -316,6 +334,76 @@ icon is not CustomIcon &&
         }
     }
 
+    /// <summary>
+    /// Drops the cached per-path answers whenever a rule's toggle or pattern changes, so an edit
+    /// in the menu takes effect on the next frame. Called once per frame, before the icon loop.
+    /// </summary>
+    private void RefreshHiddenIconRules()
+    {
+        var rules = Settings.HiddenIcons?.Content;
+        var signature = 17;
+        if (rules != null)
+        {
+            foreach (var rule in rules)
+            {
+                if (rule == null) continue;
+                signature = signature * 31 + (rule.Hide.Value ? 1 : 0);
+                signature = signature * 31 + (rule.MetadataRegex?.Value?.GetHashCode() ?? 0);
+            }
+        }
+
+        if (signature == _hiddenIconSignature) return;
+        _hiddenIconSignature = signature;
+        _hiddenIconCache.Clear();
+    }
+
+    private bool IsHiddenByRule(string path)
+    {
+        if (string.IsNullOrEmpty(path)) return false;
+        var rules = Settings.HiddenIcons?.Content;
+        if (rules == null || rules.Count == 0) return false;
+        if (_hiddenIconCache.TryGetValue(path, out var cached)) return cached;
+
+        var hidden = false;
+        foreach (var rule in rules)
+        {
+            if (rule == null || !rule.Hide.Value) continue;
+            var pattern = rule.MetadataRegex?.Value;
+            if (string.IsNullOrWhiteSpace(pattern)) continue;
+
+            var regex = GetHiddenIconRegex(pattern);
+            if (regex != null && regex.IsMatch(path))
+            {
+                hidden = true;
+                break;
+            }
+        }
+
+        _hiddenIconCache[path] = hidden;
+        return hidden;
+    }
+
+    private Regex GetHiddenIconRegex(string pattern)
+    {
+        if (_hiddenIconRegexes.TryGetValue(pattern, out var cached)) return cached;
+        // A half-typed pattern is a normal state while editing the field, so a pattern that fails
+        // to compile is reported once and then skipped rather than logged every frame.
+        if (_badHiddenIconPatterns.Contains(pattern)) return null;
+
+        try
+        {
+            var regex = new Regex(pattern, RegexOptions.Compiled);
+            _hiddenIconRegexes[pattern] = regex;
+            return regex;
+        }
+        catch (ArgumentException ex)
+        {
+            _badHiddenIconPatterns.Add(pattern);
+            LogError($"MinimapIcons: invalid hidden icon regex '{pattern}' -- rule skipped. {ex.Message}");
+            return null;
+        }
+    }
+
     private const float CameraAngle = 38.7f * MathF.PI / 180;
     private static readonly float CameraAngleCos = MathF.Cos(CameraAngle);
     private static readonly float CameraAngleSin = MathF.Sin(CameraAngle);