L-system tree · qwen3.8-2.4t-a95b
Using the pre-provided p5.min.js (global p5), grow a procedural L-system fractal tree that branches recursively and sways gently in the wind.
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Using the pre-provided p5.min.js (global p5), grow a procedural L-system fractal tree that branches recursively and sways gently in the wind.
thinking
Create a single index.html that loads p5.min.js and implements an L-system tree that sways in the wind. Let's make it look nice: draw the L-system string as line segments with turtle graphics, apply a time-based sine-wave sway to branch angles (stronger sway for more deeply nested branches). Might include a regenerate button too. Keep it self-contained.
{"command":"ls -la /tmp/ws"}total 1012 drwxr-sr-x. 2 node node 23 Aug 13 01:28 . drwxrwsrwx. 3 root node 16 Aug 13 01:28 .. -rw-r--r--. 1 node node 1034532 Aug 13 01:28 p5.min.js
thinking
Write index.html. Design: - Use an L-system: Axiom "F", rules F -> "FF+[+F-F-F]-[-F+F+F]" or something similar. Iterate about 4–5 times. - Turtle interpretation: F = forward, + = turn left, - = turn right, [ = push, ] = pop. - Wind: per-depth sinusoidal sway, add angle offset proportional to depth and time. - Draw with stroke thickness and color based on depth (brown trunk → green leaves at the tips). - Add controls: buttons to grow/regenerate, sliders, etc. Keep it simple: a "Regrow" button, plus gradual growth animation (progress). Growth animation: reveal segments over time — nice touch. - Sway: each branch segment's angle += windStrength * sin(time * freq + phase based on position/depth) * depthFactor. Implementation: precompute the tree structure as recursive segments from the L-system so wind can be applied recursively. More simply: rebuild the turtle every frame with dynamic angles — cheap enough. 4 iterations: "F" -> rule with 9 chars... rule F -> "FF-[-F+F+F]+[+F-F-F]", length grows 2^n times per F, and the number of Fs roughly triples? Let's do a rough estimate: rule with 5 Fs per F → 5^n. n=4 gives 625 Fs, plus +, -, [, ]. No problem. n=5 gives 3125 segments, still fine per frame. Use p5 global mode. Per-frame turtle with wind: wind(t, depth) = base sway + noise/sin combination. Angle offset = windAmount * sin(t*1.5 + depth*0.7 + x*0.01) * (depth/maxDepth)^1.5. Growth: animate progress from 0→1; draw only the first progress*total segment length, or scale segment length. Easiest approach: scale segment length by ease(min(1, age)), and draw partial segments to stop drawing when cumulative exceeds limit. Track draw budget: maxSegments = floor(progress * total). Leaves: draw small circles/blossoms at branch tips (when reaching ] at max depth). UI: overlay div with title, regenerate button, wind slider (maybe). Minimal, just a few buttons. Use plain HTML elements and read values inside draw. Write the file.
I'll create a self-contained L-system tree with recursive branching, animated growth, and wind sway.
/tmp/ws/index.html (9592 bytes)Successfully wrote 9592 bytes to /tmp/ws/index.html
thinking
Quickly check for syntax errors with node (extract the JS? Just a simple sanity check — run node with a stub? Easier approach: parse with `node --check`? The script uses browser globals, but `node --check` only parses syntax).
{"command":"cd /tmp/ws && python3 -c \"\nimport re\nhtml = open('index.html').read()\njs = re.findall(r'<script>(.*)</script>', html, re.S)[/bin/bash: line 1: python3: command not found Command exited with code 127
thinking
Extract with node instead.
{"command":"cd /tmp/ws && node -e \"\nconst fs=require('fs');\nconst html=fs.readFileSync('index.html','utf8');\nconst m=html.match(/<scriptSYNTAX_OK -rw-r--r--. 1 node node 9604 Aug 13 01:29 index.html -rw-r--r--. 1 node node 1034532 Aug 13 01:28 p5.min.js
thinking
Should I also quickly verify the headless behavior? Can't easily run p5 without a browser. The syntax is OK, and the logic is reasonable. One concern: `random` is used inside the IIFE within draw, but — this is fine since p5's globals are registered on window, and draw is executed after setup. `leaves` is declared with const at the end of the IIFE but is referenced inside draw — hoisting: `const leaves` is in the TDZ until that line executes, but since the IIFE completes before setup/draw runs, there's no problem. Done.
Done. `index.html` is in place at `/tmp/ws/index.html` — fully self-contained, loading only the local `p5.min.js`. **What it does:** - **L-system grammar** — starts from axiom `F` and iterates a *stochastic* rule set (three `F →` productions chosen by probability), so every tree has a unique shape. Interpreted turtle-style: `F` draw, `+`/`-` turn, `[`/`]` push/pop branch state. - **Recursive fractal branching** — bracket depth drives visuals: thick brown bark at the trunk lerps to thin green tips, with leaf clusters and occasional pink blossoms at the outermost branches. - **Gentle wind sway** — layered sine waves with a slow gust envelope (`windAt`) add an angle offset to each segment, scaled by `(depth/maxDepth)^1.4` so the trunk barely moves while outer twigs flutter. When breezy, detached leaves drift off and tumble with the wind. - **Growth animation** — the tree grows from the ground up over ~4s with cubic ease-out, including partial-segment rendering for a smooth tip. - **Scene** — night-sky gradient, twinkling stars, crescent moon, grassy ground. - **Controls** — sliders for wind strength, branch angle, and iteration depth (3–5, up to ~3,000+ segments), plus a 🌱 Regrow button that reseeds the stochastic grammar. JS syntax verified with `node --check`. No network requests anywhere.
TAKE IT TO CODE
A single self-contained HTML file — copy it and open in any browser, or reuse the prompt with your own pi-agent run.
RUN
EVALUATION
A procedural L-system tree renders with slight sway, sliders for wind/angle/depth, but tree is oddly thin and elongated.
Vision grade · anthropic/claude-sonnet-5
MEASUREMENTS
Raw readings from the capture, not a verdict — the grade above is the only judgement. Percentages are how much of the screen changed; the measure under-reports sparse motion on a dark background.