Mobhighlight

Mob Highlight

Draws vanilla glowing outlines over mobs within a radius — the spectral-arrow look, visible through walls — colored by rule. Modded entities included, with an in-game configuration screen.

It rides the vanilla outline pipeline, so the outline hugs the entity model itself rather than drawing a hitbox-style box.

Client-side only, no Mixin, nothing to install on the server.

Requires: Minecraft 1.21.11 · Fabric Loader 0.18.4 or newer · Fabric API

中文说明见 README.md。

Installation

Drop mobhighlight-<version>.jar and Fabric API into your mods/ folder.

Delete any older mobhighlight-*.jar first — two jars with the same mod id will abort startup.

Controls

Key	Action
H	Toggle, with an on/off message in chat
J	Open the configuration screen
] / [	Detection radius ±8 blocks

Both keys can be rebound from the General tab, which links to the vanilla Controls screen.

Configuration screen

Five tabs:

• General — master switch, through-wall display, invisible entities, outline yourself, radius, per-frame cap, correction interval, keybinds

• Default Rules — the seven auto-sorted categories (Player / Friendly / Neutral / Hostile / Aquatic / Ambient / Other), each with a toggle and a color swatch

• Custom Rules — pick your own entities, name them, give them a color (see below)

• Entity List — every entity including modded ones, with search and filter by mod. Each row cycles three states: follow rules / force glow / never glow

• Mod Sources — per-mod master toggle, the quick way out when a mod turns out to be incompatible

Through-wall display is on by default, which is the vanilla glow behavior at no extra cost. Turning it off outlines only what you can see, at the price of a raycast per frame.

Anything you change is written to config/mobhighlight.json immediately.

About the rules

Default rules sort entities by tag and registered category, with no hardcoded mob list anywhere, so modded mobs land in a sensible category on their own.

Where that gets it wrong, you can pull entities out with your own rule. Villagers are the usual example: registered as MISC with no category tag, so default rules can only file them under "Other". Click "Add entity" to get the category list, open a category, pick the entities — from then on they use that rule's color instead.

An entity already claimed by another rule shows up greyed out and unclickable; remove it from its current rule first. Removing an entity, or deleting the whole rule, puts it back on its default category and color right away.

Commands

Known issues

1. Some mods register an entity renderer without an outline variant. Rendering then throws Can't render an outline for this rendertype! and the game may crash. Vanilla glow has the same limitation — this mod just marks more entities at once and so hits it more easily. If it happens, search the log for that line and turn the offending mod off on the Mod Sources tab.

1. There is no way to tell yourself apart from other players, so anything closer than one block to the camera is treated as you and skipped. Set glowSelf to outline yourself too.

Building

JDK 21 and Gradle 9.x are needed (Loom 1.17 requires Gradle 9 or newer). From the project root:

The jar lands in build/libs/, named after mod_version in gradle.properties.

License

MIT