Flashlight: Shader Light Engine

A real flashlight for Minecraft. Smooth beam, honest shadows, blinding glare.

Every flashlight mod does the same trick: invisible light blocks chasing your crosshair, chunky relights, light leaking through walls. Flashlight doesn't. It ships its own shader-driven light engine — a smooth volumetric cone that updates every frame, stops at walls, casts soft shadows and blinds anyone who looks into the lens. Built as the companion to Enhanced Darkness: in its pitch black you'll need one.

✦ Two lights, two jobs

	🔦 Flashlight	💡 Work Lantern
Role	cheap all-rounder	expensive floodlight
Beam	scroll to focus the lens: wide 25-block flood ↔ razor-thin 150-block spot	fixed ~40° wall of light, 55 blocks
Power	AA battery — 30 min	battery pack — 45 min
Recipe	iron + redstone + glass	gold, iron, redstone block

• Right-click — on/off. R — slam a fresh battery in, gun-reload style, with a chest-pull animation.
• Mouse wheel (flashlight on) — zoom the lens: floodlight for corridors, sniper beam for scouting.
• Batteries are consumables. Below 20% charge the beam visibly dies — reload or walk in the dark.

✦ The engine

No light blocks. No chunk relights. The cone is computed inside the game's core shaders — terrain, entities, dropped items, particles and even vanilla mob shadow blobs are cloned on the fly with the beam math injected. That means:

• Instant — the light moves the frame you move, with a subtle hand-lag inertia like a real torch.
• Honest — light is albedo × cone: real textures, real colours, zero noise, works in absolute darkness.
• Blocked by walls — a 48³ voxel map around the camera is ray-marched (DDA) per pixel; soft penumbra from three jittered rays, entities cast soft sphere shadows, and the beam dissolves vanilla shadow circles it hits.
• Multiplayer-native — up to four beams at once; everyone sees everyone's light, zoom level included.
• Blinding — glare is physics, not a sprite: its strength equals the actual cone intensity at your eyes, traced past blocks and mobs. Look into a lens up close and the screen whites out.
• Sodium-ready — with Sodium installed the beam is injected straight into its terrain shaders. Same light, same shadows, Sodium speed.

✦ Installation

1. Install Fabric Loader for Minecraft 26.1.x.
2. Install Fabric API.
3. Run Java 25.
4. Drop the jar into mods — on the client and the server (items and batteries are real).
5. Pairs best with Enhanced Darkness.

⚠️ Iris shaderpacks replace the game's shaders entirely — with a pack enabled the beam won't light terrain. Sodium alone works out of the box.

✦ License

MIT — source on GitHub.