git:20260710.ffb3400 to git:20260710.0115f49

20 added, 20 removed. Audit A to A.

---

name: spirograph-python-matplotlib

- description: Create easy Python scripts that generate beautiful, unique spirograph-style generative art with Matplotlib, support multi-color or gradient background and main palettes, and always save the result as a PNG. Use when the user asks for creative coding, spirographs, procedural art, or quick art scripts with tunable inputs.

+ description: Create easy Python scripts that generate beautiful, unique spirograph-style generative art with Matplotlib, support multi-colour or gradient background and main palettes, and always save the result as a PNG. Use when the user asks for creative coding, spirographs, procedural art, or quick art scripts with tunable inputs.

metadata:

skill-author: 'arcanum-artifex'

---

# Spirograph Python Matplotlib

## What this skill does

This skill creates beginner-friendly Python scripts for creatives to generate spirograph-inspired artwork using Matplotlib.

The scripts produced by this skill:

- Accept user inputs for geometry and style.

- - Ask for both background color and main color inputs.

- - Support multiple colors for each palette and gradient blending.

+ - Ask for both background colour and main colour inputs.

+ - Support multiple colours for each palette and gradient blending.

- Ensure each output is unique by combining deterministic parameters with a uniqueness mechanism.

- Always save a PNG output file.

## When to use it

Use this skill when the user asks for:

- Spirograph or hypotrochoid/epitrochoid-style art in Python.

- Generative art scripts that are easy to run and modify.

- - Colorful creative outputs with gradients.

+ - Colourful creative outputs with gradients.

- Script-first workflows where PNG exports are required.

Do not use this skill for:

- Real-time GPU rendering pipelines.

- 3D engines or game frameworks.

- Non-Python stacks unless explicitly requested.

## Inputs the generated script should support

At minimum, the generated script should ask for:

- Geometry controls:

- `R` (outer radius)

- `r` (inner radius)

- `d` (offset)

- `points` (sampling density)

- `rotations` (curve coverage)

- Uniqueness controls:

- `seed` (optional deterministic repeatability)

- `variation_strength` (small randomized perturbation)

- `output_name` (PNG filename stem)

- Styling controls:

- - `background_colors` (one or more colors)

- - `main_colors` (one or more colors)

+ - `background_colors` (one or more colours)

+ - `main_colors` (one or more colours)

- `use_gradient` (`yes`/`no`)

- `line_width`

- `alpha`

- `figure_size`

- Color input can be hex (`#1f77b4`), CSS-like names (`gold`), or comma-separated lists.

+ Colour input can be hex (`#1f77b4`), CSS-like names (`gold`), or comma-separated lists.

## Instructions

1. Confirm objective and constraints.

- Restate that the script will be easy to run, produce unique outputs, and save PNG files every run.

2. Generate a single-file Python script first.

- Prefer one script (for example, `spirograph_art.py`) with clear sections:

- input parsing

- - color parsing and gradient helpers

+ - colour parsing and gradient helpers

- curve generation

- rendering

- PNG export

3. Implement spirograph math with stable defaults.

- Use a parametric curve (hypotrochoid or epitrochoid) and expose `R`, `r`, `d`, `points`, and `rotations`.

- Validate numeric ranges and provide beginner-safe defaults.

4. Enforce uniqueness per output.

- If `seed` is provided, use it for deterministic uniqueness.

- If no `seed` is provided, derive one from time + entropy.

- Apply controlled perturbations (`variation_strength`) to one or more geometry or style parameters.

- Include the seed in the output filename or metadata text on-canvas.

- 5. Implement background and main color systems.

+ 5. Implement background and main colour systems.

- - Parse single or multi-color input lists.

- - If multiple colors are supplied and gradient is enabled:

- - interpolate smoothly across the background and/or stroke colors.

+ - Parse single or multi-colour input lists.

+ - If multiple colours are supplied and gradient is enabled:

+ - interpolate smoothly across the background and/or stroke colours.

- If gradient is disabled:

- cycle or randomly choose from provided palettes in a seed-controlled way.

6. Render for visual quality.

- Use a high DPI figure.

- Hide axes and margins.

- Use anti-aliased lines.

- - Center and scale composition for balanced framing.

+ - Centre and scale composition for balanced framing.

- Prefer dark-on-light or light-on-dark contrast checks when possible.

7. Always export PNG.

- Save output on every run with `bbox_inches='tight'` and consistent DPI.

- Confirm save path in terminal output.

- Never skip file export, even if display fails.

8. Add usage instructions.

- Provide run command and one example input set.

- Keep explanation concise and creative-focused.

## Quality checks

- Before finalizing, verify:

+ Before finalising, verify:

- Script runs with Python + Matplotlib only (unless user asks for extras).

- - Both background and main color prompts exist.

- - Multi-color and gradient behavior works for both palettes.

+ - Both background and main colour prompts exist.

+ - Multi-colour and gradient behaviour works for both palettes.

- Two consecutive runs produce different outputs when no fixed seed is set.

- Same seed reproduces the same image.

- PNG file is always written.

## Output format

When using this skill, produce:

1. File edits:

- A runnable Python script (or minimal set of scripts) in the requested location.

2. Short run instructions:

- Dependencies and command to execute.

- 3. Save confirmation behavior:

+ 3. Save confirmation behaviour:

- Explain where PNGs are written and how names are generated.

4. Optional creative presets:

- Include 2-3 input presets (for example: neon bloom, monochrome etch, sunset ribbon).

## Example prompts

- "Create an easy Python spirograph script with gradient background and always save PNG."

- - "Make a creative coding script for unique spirograph art; ask me for multiple background and line colors."

+ - "Make a creative coding script for unique spirograph art; ask me for multiple background and line colours."

- "Build a Matplotlib spirograph generator with seed control and deterministic reruns."

## Ambiguities to confirm with the user

If not specified, ask these before final implementation:

- Should this be CLI prompts, command-line arguments, or both?

- Should gradients apply to background only, main lines only, or both?

- - Should uniqueness rely mostly on geometry variation, color variation, or both?

+ - Should uniqueness rely mostly on geometry variation, colour variation, or both?

- Preferred default canvas size and DPI?

If the user does not answer, default to:

- CLI prompts

- gradient support for both background and main lines

- - mixed geometry + color variation

+ - mixed geometry + colour variation

- `figsize=(8, 8)`, `dpi=300`