lightning

lightning — Procedural Jagged Bolt

A lightning bolt is a noisy line from A to B, drawn for ~150 ms with a glow shader, sparks at both endpoints, and camera shake on cast. The recipe builds the jagged path in GDScript (midpoint displacement on a polyline), feeds the verts into an ImmediateMesh, applies a ShaderMaterial for additive bloom + flicker, spawns hit-spark particles at each endpoint, and calls CameraShake.add_trauma(0.6) for the impact. Used for shock spells, tesla coils, weapon discharges, electric enemies.

When to use

• "Cast a lightning bolt from the wizard's hand to the enemy."
• "Chain lightning from one enemy to the next." (call cast_lightning per segment)
• "Tesla coil firing at the player every 2 seconds."
• "Energy weapon laser." (use the laser-beam variant)
• "Lightning strike from the sky."
• The user wants a short, dramatic energy connection between two points.

When NOT to use

• The user wants a continuous beam that holds (e.g., laser sniper holding the trigger) — use the same shader on a MeshInstance3D cylinder with continuous emission, not the ImmediateMesh one-shot pattern. (See variants for held-beam.)
• The user wants ambient electricity on an object (Frankenstein arcs) — use a custom shader on the mesh with screen-space arcs; this recipe is for two-point bolts.
• The user wants a 2D lightning effect on UI — canvas_item shader, not this.
• The user wants a tracer line for a bullet — use a simple ImmediateMesh without noise displacement; skip this recipe. The current Summer build has no Line3D (ClassDB.class_exists("Line3D") is false); Line2D is 2D-only.

Recipe

1. Files to create

addons/vfx/lightning/lightning.gdshader     # spatial shader for the bolt mesh
addons/vfx/lightning/lightning_caster.gd     # build path, draw, animate, spawn endpoints, shake
addons/vfx/lightning/lightning.tscn          # reusable scene

2. Shader code

addons/vfx/lightning/lightning.gdshader: