Easy PatternsAnimated

Scrolling circle with a dark vignette

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

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The target picture for the shader challenge "Scrolling circle 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 397 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: Scroll: p.x += time * 0.15
Step 2: Pattern: d = length(p) - 0.24; m = 1.0 - smoothstep(0.0, 0.006, d)
Step 3: Colors: lerp(float3(0.17, 0.07, 0.09), lerp(float3(0.83, 0.56, 0.42), float3(0.38, 0.82, 0.72), uv.y), m)
Step 4: Finish: col *= 1.0 - 0.55 * smoothstep(0.4, 0.9, 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.

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How this challenge works

The numbers you need

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