Highlight API
by NOIST1611
Highlight API is a Forge library that lets other mods draw outlines and filled regions around blocks, entities and arbitrary boxes in the world.
What it does
Highlight API supports custom highlights for blocks and entities, drawing outline or filled shapes around axis-aligned bounding boxes. A region can be marked between two block positions, so a single highlight covers a whole area. Each highlight can carry its own line width, colour treatment and lifetime, and highlights can be set to persist indefinitely with delayed removal.
Other mods that depend on the library can choose how a highlight reacts to terrain. One depth mode keeps the outline hidden behind blocks, while the other draws it visible through walls. Built-in animations named Pulse, Blink and Fade cover common cases, and a custom animation can be added through the ICustomAnimation interface. The library is built for Forge 1.20.1 and is client-side only, so it adds nothing to the server.
Key features
Block and entity outlines
Outlines and filled shapes can be drawn around blocks, entities and axis-aligned bounding boxes.
Region highlighting
A region is defined by two block positions, and the highlight covers the box between them.
Built-in animations
Pulse, Blink and Fade are available out of the box, and custom animations can be registered through an interface.
Depth control
Highlights can be hidden behind blocks or drawn visible through them, selected per highlight.
Lifetime and line width
Highlights can persist for an eternal, delayed lifetime, and the line width of each outline can be set.
Gallery
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Mod developers
Developers who want to mark blocks, entities or regions in their own mod can call the library rather than writing rendering code.
Debugging and building
A highlighted region between two positions shows the area a feature covers during testing.
Who it’s for: Mod developers building Forge 1.20.1 content that needs world highlights, and players who run a mod depending on this library.
Questions
Does Highlight API need to be on the server?
Which Minecraft version does Highlight API support?
Is the source code available?
How is a custom animation added?
In the catalog
Highlight API is one of 3,514 Library mods on ModsFinder, and one of 1,576 Library mods for Forge. 34,764 mods support Minecraft 1.20.1.
More from NOIST1611
Similar mods
What the author says
A Minecraft Forge 1.20.1 library mod that adds support for custom highlights and outlines for blocks, entities and regions.
Official listing
- Modrinth page
- modrinth.com/mod/highlight-api
- Owner
- NOIST1611
- Published
- 2026-06-15
- Updated on Modrinth
- 2026-06-19
- Facts verified
- 2026-10-15