git:20260515.a7881b0 to git:20260515.b861afb

2 added, 2 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.
+ name: spirograph-python-matplotlib
metadata:
- skill-author: arcanum-artifex
+ 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.
- 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.
- 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)
- `use_gradient` (`yes`/`no`)
- `line_width`
- `alpha`
- `figure_size`
Color 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
- 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.
- 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.
- 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.
- 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:
- 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.
- 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:
- 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."
- "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?
- 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
- `figsize=(8, 8)`, `dpi=300`