GPT-6 Astra generates a black-hole simulation that runs in the browser

A single demo, not an official launch

Researcher elvis posted a screenshot and short video on X showing GPT-6 Astra, OpenAI's new model, writing from scratch an interactive web page that simulates a journey into a black hole. The code executes directly in the browser with no external libraries or build tools.

Vanilla JavaScript, HTML, CSS, and custom shaders

The model used plain JavaScript alongside HTML and CSS for page structure, then added custom shaders in WebGL and GLSL. That WebGL/GLSL layer does the heavy lifting: the GPU computes the scene in parallel across every pixel instead of marching through them serially on the CPU.

Shaders on the GPU — not trivial for a language model

Producing valid GLSL that compiles and runs error-free requires understanding the render pipeline, GPU data types, and floating-point precision limits. The fact that the model delivered working code on the first try, or at least in the version shown, signals high-level coding ability in a domain that remains niche even for experienced developers.

One source, no metrics, no comparisons

The claim rests on a single tweet — no technical paper, no official product page, no reproducible benchmark. No runtime figures, memory usage, image quality versus a physics reference, or comparison with earlier model versions have been published. There is no way to know whether the example was cherry-picked from dozens of failed attempts.

Availability and access still unknown

No timeline has been given for when GPT-6 Astra will reach developers, through which interface — API, chat, coding environment — or whether licensing restrictions will apply to generated code. It also remains unclear whether the shader-writing capability is a general property of the model or the result of targeted training on a computer-graphics corpus.