Easy Patterns

Grid with a dark vignette

A picture built in steps: draw grid, then color it, then finish with a dark vignette. Every step is listed below with its exact numbers.

The target picture for the shader challenge "Grid with a dark vignette"
Recreate this picture. You pass at a 99% match, then try to write it in fewer characters than the par.

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 342 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

Space
p = (uv - 0.5) * float2(aspect, 1.0)
Step 1: Pattern
e = abs(frac(p * 5.0) - 0.5); m = step(0.47, max(e.x, e.y)) (lines on the cell borders)
Step 2: Colors
lerp(float3(0.07, 0.17, 0.08), float3(0.37, 0.94, 0.6), m)
Step 3: Finish
col *= 1.0 - 0.75 * smoothstep(0.4, 0.95, length(s)), s = (uv - 0.5) * float2(aspect, 1.0)

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