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Medium 2DAnimated

Beating heart

A heart that pulses, using an implicit equation.

Play this challenge All challenges

The target picture for the shader challenge "Beating heart" — 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 330 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: q = (uv - 0.5) * float2(aspect, 1.0) * 2.6
Pulse: q = q / (1.0 + 0.1 * sin(time * 6.0))
Shift: q.y += 0.15
Equation: a = dot(q,q) - 1; h = a*a*a - q.x*q.x*q.y*q.y*q.y; inside when h < 0
Edge: 1.0 - smoothstep(-0.01, 0.01, h)
Colors: float3(0.1,0.05,0.12) / float3(0.95,0.2,0.35)

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.