ShaderBattle

Medium Filters

Box blur

Blur the picture by averaging a 5 × 5 neighbourhood of samples.

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The target picture for the shader challenge "Box blur"
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 797 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

Radius
2 samples each way (5 × 5 = 25 samples)
Spacing
0.006 in uv units per step, in both x and y
Average
sum of all samples divided by 25

Helper functions provided

The toolbox has: scene(). 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

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