Medium EffectsAnimated
Digital rain
Green code columns falling at different speeds, with bright heads and fading tails.
How this challenge works
You write a fragment shader that draws the picture above, live in your browser. A match bar shows how close you are, and the score combines accuracy, code size (the par is 566 characters in Unity (Built-in)) and GPU speed. Work in HLSL, GLSL, WGSL, Metal or Godot and export the result when you are done.
The numbers you need
- Grid
cells = float2(40.0, 30.0): g = floor(uv * cells), f = frac(uv * cells)- Per column
h = hash(float2(g.x, 0.0)), speed = 0.3 + h * 0.7- Head
head = frac(time * speed * 0.5 + h * 7.0)- Trail
exp(-frac(uv.y - (1.0 - head)) * 4.0)- Glyph on/off
step(0.35, hash(g + floor(time * 8.0 * h)))- Glyph box
step(0.15, f.x) * step(f.x, 0.85) * step(0.15, f.y) * step(f.y, 0.85)- Color
float3(0.1, 1.0, 0.3) * trail * glyph * box, on black
Helper functions provided
The toolbox has: hash(). Add them above your frag function with one click.
Solve it in your language
Unity (Built-in), Unity (URP), Unreal, Shadertoy / WebGL, OpenGL (LWJGL, raylib), three.js, GameMaker, LÖVE (Lua), Godot, Apple (iOS, macOS), WebGPU / Bevy.
Start coding