NPC Highlighter

1package com.example;
2
3import net.runelite.api.Client;
4import net.runelite.api.NPC;
5import net.runelite.api.events.NpcSpawned;
6import net.runelite.api.events.NpcDespawned;
7import net.runelite.client.eventbus.Subscribe;
8import net.runelite.client.plugins.Plugin;
9import net.runelite.client.plugins.PluginDescriptor;
10import net.runelite.client.ui.overlay.Overlay;
11import net.runelite.client.ui.overlay.OverlayManager;
12import net.runelite.client.ui.overlay.OverlayLayer;
13import javax.inject.Inject;
14import java.awt.*;
15import java.util.HashSet;
16import java.util.Set;
17
18@PluginDescriptor(
19    name = "NPC Highlighter",
20    description = "Highlights NPCs on screen"
21)
22public class NPCHighlighterPlugin extends Plugin {
23    @Inject
24    private Client client;
25
26    @Inject
27    private OverlayManager overlayManager;
28
29    // Track interesting NPCs using events (much better performance)
30    private final Set<NPC> highlightedNPCs = new HashSet<>();
31
32    @Subscribe
33    public void onNpcSpawned(NpcSpawned event) {
34        NPC npc = event.getNpc();
35        if (npc.getName() != null && npc.getName().contains("Goblin")) {
36            highlightedNPCs.add(npc);
37        }
38    }
39
40    @Subscribe
41    public void onNpcDespawned(NpcDespawned event) {
42        highlightedNPCs.remove(event.getNpc());
43    }
44
45    private final Overlay overlay = new Overlay() {
46        @Override
47        public Dimension render(Graphics2D graphics) {
48            // Only render tracked NPCs (much better performance)
49            for (NPC npc : highlightedNPCs) {
50                // Use Perspective to get NPC's model center point
51                net.runelite.api.coords.LocalPoint localPoint = 
52                    net.runelite.api.coords.LocalPoint.fromWorld(client, npc.getWorldLocation());
53                if (localPoint != null) {
54                    Point screenPoint = net.runelite.api.Perspective
55                        .localToCanvas(client, localPoint, client.getPlane());
56                    if (screenPoint != null) {
57                        // Draw highlight
58                        graphics.setColor(new Color(255, 0, 0, 100));
59                        graphics.fillOval(screenPoint.x - 20, screenPoint.y - 20, 40, 40);
60                        graphics.setColor(Color.RED);
61                        graphics.drawOval(screenPoint.x - 20, screenPoint.y - 20, 40, 40);
62                    }
63                }
64            }
65            return null;
66        }
67    };
68
69    {
70        overlay.setLayer(OverlayLayer.ABOVE_SCENE);
71    }
72
73    @Override
74    protected void startUp() {
75        overlayManager.add(overlay);
76    }
77
78    @Override
79    protected void shutDown() {
80        overlayManager.remove(overlay);
81    }
82}