Chunk Border Redstone Highlighter

One of the biggest causes of lag on high-performance servers: redstone circuits placed across chunk borders. This client-side mod highlights those risky blocks around you with a red wireframe box, letting you spot chunk-boundary issues before they hurt your TPS.

Why Are Chunk-Border Redstone Components Bad?

Minecraft splits the world into 16x16 chunks. Each chunk is loaded, saved, and ticked independently. When a redstone signal crosses a chunk boundary:

• Both chunks need to be updated every tick
• Observers, pistons, and hoppers trigger extra chunk load/save cycles
• Paper, Purpur, and Folia suffer the most because of their async chunk systems
• Synchronization locks are held across the boundary on async chunk implementations

Features

• One-key toggle — default O (rebindable in Options > Controls)
• 32-block radius scan around the player — finds every risky block nearby
• Smart boundary detection — uses localX == 0 || localX == 15 || localZ == 0 || localZ == 15 math (works correctly on negative coordinates too)
• Detected blocks:
  • Redstone
  • Repeater
  • Comparator
  • Observer
  • Piston (normal + sticky)
  • Hopper
• Minimal performance impact — scans every 10 ticks, only inspects border columns
• Uses 1.21.11's new Gizmo render API — clean, bug-free rendering
• No server-side install needed — client-only, works on any server

Usage

1. Download this mod and Fabric API
2. Drop both into your .minecraft/mods/ folder
3. Join a world or server
4. Press O — nearby chunk-border redstone components get wrapped in a red wireframe
5. Press O again to disable

Compatibility

Feature	Support
Minecraft	1.21.11
Mod Loader	Fabric (Loader 0.18.0+)
Fabric API	Required
Java	21+
Side	Client-only

Untested

• Quilt: Not tested, but should work since Quilt supports Fabric mods
• Forge/NeoForge: Not supported