heatslop#

A dumb-but-fun space heater app that maxes out your CPU and GPU to warm up your room. It renders a procedural fire animation on the GPU while all your CPU cores brute-force search for prime numbers.

Yes, it is exactly as stupid as it sounds.

What it does#

• GPU: Runs a 3-pass fire shader (generation, gaussian blur, bloom composite) as fast as possible with vsync off. Your GPU will earn its electricity bill.
• CPU: Every core runs trial division to find primes. The title bar shows how many primes have been found and how many primality tests are happening per second.
• Title bar: Live FPS, core count, primes found, and tests/sec for primes.

Screenshot#

It's fire. On your screen. You get it.

Building & Running#

cargo run --release

Press ESC or close the window to stop.

--release matters. You want optimized prime crunching if you're going to waste electricity.

The fire shader#

The fire effect is from ddsol's "Bring the Heat" on Shadertoy. The original GLSL is preserved unmodified in src/shaders/shadertoy/. A Rust adapter module wraps it with wgpu preambles and applies two minimal workarounds for naga's GLSL parser limitations (precomputed matrix product, hardcoded array sizes). The original code is never touched.

Credit and thanks to ddsol for the shader.

The slop disclosure#

This project was written almost entirely by an LLM. I designed the architecture (how the pieces connect, what the passes do, the module structure), but the vast majority of the code came out of wasting electricity. Hence the name.

This is not representative of how I normally work. My actual public-facing projects are not like this. When I use LLMs in real work, I read every single line, understand every single part, and treat the output as a starting point, not a finished product. This project exists because I wanted a space heater.

If you're wondering which LLM I used: I'm not saying. I don't do free advertising :p

License#

Dual licensed:

• The Rust code (everything except src/shaders/shadertoy/) is under the MIT License.
• The fire shader (src/shaders/shadertoy/) is by ddsol. I didn't find a specific license on the shader itself, but the default license for Shadertoy shaders is CC BY-NC-SA 3.0.