oneshotlm
Compare all models on this prompt →

Bouncing balls in a heptagon · qwen3.6-flash

Show 20 numbered balls (1 to 20) dropping from the center of a heptagon that spins 360 degrees every 5 seconds. The balls are affected by gravity and friction, collide with each other, and bounce realistically off the rotating walls; show each ball's spin via the rotation of its number. Implement all collision detection yourself.

⛨ sandboxed Open in new tab ↗
transcript · 6 messages
user

Show 20 numbered balls (1 to 20) dropping from the center of a heptagon that spins 360 degrees every 5 seconds. The balls are affected by gravity and friction, collide with each other, and bounce realistically off the rotating walls; show each ball's spin via the rotation of its number. Implement all collision detection yourself.

assistant
thinking
The user wants a single-page web app with:
1. A spinning heptagon (7-sided polygon) that rotates 360° every 5 seconds
2. 20 numbered balls (1-20) dropping from the center
3. Physics simulation with gravity, friction
4. Ball-to-ball collisions
5. Ball-to-wall collisions (bouncing off rotating walls)
6. Ball spin visualization (rotation of the number on each ball)
7. All collision detection implemented manually

This is a complex physics simulation. Let me build it step by step using Canvas API.

Key physics considerations:
- The heptagon rotates, so wall collision normals change over time
- Need to compute the current vertex positions based on rotation angle
- Ball-wall collision: reflect velocity relative to wall normal, account for wall motion
- Ball-ball collision: elastic collision with proper momentum transfer
- Gravity pulls balls down
- Friction/damping slows things gradually
- Each ball has angular velocity for its spin

Let me write this comprehensive simulation.
write /tmp/ws/index.html (11528 bytes)
toolResult

Successfully wrote 11528 bytes to /tmp/ws/index.html

assistant
thinking
The file has been created. Let me verify it exists and is complete.
bash {"command":"wc -l /tmp/ws/index.html && head -3 /tmp/ws/index.html && echo \"---\" && tail -3 /tmp/ws/index.html"}
toolResult

405 /tmp/ws/index.html <!DOCTYPE html> <html lang="en"> <head> --- </script> </body> </html>

assistant
thinking
The file is created and ready. Let me provide a summary to the user.

Done! `index.html` has been written with all CSS, JS, and HTML in one self-contained file. Here's what it implements: **Physics Engine:** - **Gravity** pulls all 20 numbered balls downward at 980 px/s² - **Friction** (0.985 per frame) gradually slows motion - **Restitution coefficient** (0.7) for realistic bouncing off walls and each other - **4 sub-steps** per frame for stable collision resolution **Rotating Heptagon:** - Spins a full 360° every 5 seconds (`ω = 72°/s`) - Ball-wall collisions compute the wall's rotational velocity at the contact point, imparting realistic momentum transfer - Tangential friction on wall contact imparts spin to balls **Collision Detection (all implemented from scratch):** - **Ball vs Wall**: Finds closest point on each heptagon edge segment, resolves overlap, computes impulse along surface normal with wall-velocity-relative reflection - **Ball vs Ball**: Computes distance between centers, separates overlapping spheres, exchanges velocities along the collision normal using mass-weighted impulse equations, transfers tangential velocity into angular spin **Visual Features:** - Each ball is color-coded by its number (hue spectrum from 1→20) - Radial gradient highlights with specular-like sheen - Numbers rendered white inside each ball; an orientation dot tracks rotation - Balls glow via canvas shadow blur - Glowing heptagon with vertex dots and subtle interior fill - Background radial gradient from deep blue to near-black

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

modelqwen3.6-flash
vendorQwen
harnesspi-agent
generated2026-08-01

EVALUATION

3/5 working

Numbered balls fall and pile against rotating heptagon wall under gravity, but balls always cluster at one vertex without spreading around, and no interactive controls change behavior.

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.

idle motion7.0%
on click6.7%
on drag6.3%
on wheel6.6%
on enter + space6.6%
on arrow keys6.7%
on w/a/s/d6.7%
frame spread19.6 / 255
console errors0
js errors none

METRICS

runtime27.6s
tokens in13k
tokens out4.4k
cached0
cost / run$0.0073