Hard EffectsAnimated
Spinning polar grid with a border
A picture built in steps: spin, then polar coordinates, then draw grid, then color it, then finish with a border. Every step is listed below with its exact numbers.
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 596 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: Spin
turn p by time * -0.9 radians: c = cos(angle), s = sin(angle), p = float2(c * p.x + s * p.y, -s * p.x + c * p.y)- Step 2: Polar coordinates
p = float2(atan2(p.y, p.x) / 3.1415927, length(p) * 2.0) (x = angle from -1 to 1, y = distance)- Step 3: Pattern
e = abs(frac(p * 4.0) - 0.5); m = step(0.42, max(e.x, e.y)) (lines on the cell borders)- Step 4: Colors
lerp(float3(0.19, 0.09, 0.15), lerp(float3(0.88, 0.32, 0.54), float3(0.43, 0.9, 0.75), uv.y), m)- Step 5: Finish
edge = min(min(uv.x, 1.0 - uv.x), min(uv.y, 1.0 - uv.y)); col = lerp(float3(0.73, 0.56, 0.97), col, smoothstep(0.04, 0.046, edge))
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