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3 posts tagged “ray-tracing”

2025

Pelican on a Bike—Raytracer Edition (via) beetle_b ran this prompt against a bunch of recent LLMs:

Write a POV-Ray file that shows a pelican riding on a bicycle.

This turns out to be a harder challenge than SVG, presumably because there are less examples of POV-Ray in the training data:

Most produced a script that failed to parse. I would paste the error back into the chat and let it attempt a fix.

The results are really fun though! A lot of them end up accompanied by a weird floating egg for some reason - here's Claude Opus 4:

3D scene. The bicycle has a sort of square frame in the wrong place, but good wheels. The pelican is stood on top - a large white blob, a smaller white blob head, a cylinder neck and a conical beak in the right place, plus legs that reach out-of-place pedals. A egg floats mysteriously in front of the bird.

I think the best result came from GPT-5 - again with the floating egg though!

The bike is a bit mis-shapen but has most of the right pieces. The pelican has legs that reach the pedals and is bending forward with a two-segmented neck and a good beak. A weird egg floats in the front wheel.

I decided to try this on the new gpt-5-codex-mini, using the trick I described yesterday. Here's the code it wrote.

./target/debug/codex prompt -m gpt-5-codex-mini \
  "Write a POV-Ray file that shows a pelican riding on a bicycle."

It turns out you can render POV files on macOS like this:

brew install povray
povray demo.pov # produces demo.png

The code GPT-5 Codex Mini created didn't quite work, so I round-tripped it through Sonnet 4.5 via Claude Code a couple of times - transcript here. Once it had fixed the errors I got this:

Two wheels (tire only) sit overlapping half embedded in the ground. The frame is a half-buried red triangle and some other lines. There is a white pall with a tiny yellow beak and two detached cylindrical arms. It's rubbish.

That's significantly worse than the one beetle_b got from GPT-5 Mini!

# 9th November 2025, 4:51 pm / 3d, ray-tracing, ai, generative-ai, llms, pelican-riding-a-bicycle, gpt-5

2024

City In A Bottle – A 256 Byte Raycasting System (via) Frank Force explains his brilliant 256 byte canvas ray tracing animated cityscape demo in detail.

# 26th May 2024, 6:25 pm / demoscene, javascript, ray-tracing

2008

WolfenFlickr 3D—An unlikely mashup. Brilliant: Wolfenstein 3D style raycasting in JavaScript with images on the walls that have been pulled in using Flickr’s JSONP API.

# 29th August 2008, 10:24 am / flickr, javascript, jsonp, ray-tracing, wolfenflickr, wolfenstein3d

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