STARDRAW

What is Stardraw?

Stardraw is a browser toy that converts the shape of your cursor movement into a named star constellation. Click and drag any path on the canvas — a spiral, a signature, a rough circle, a jagged zigzag. When you release, the Ramer-Douglas-Peucker algorithm walks the recorded path and finds its key inflection points: the moments where your direction changed most significantly. Those points become stars. Lines are drawn between consecutive stars to complete the constellation figure.

Each constellation receives a two-word Latin name and a three-sentence mythology, both derived from the FNV-32 hash of the star coordinates. The same drawing always produces the same result — the outcome is deterministic, not random. A URL-encoded version of the star positions is written to the fragment, so any constellation can be shared as a link.

How It Works

• ◈Path recording. As you click and drag, mouse positions are recorded whenever the cursor moves more than 2.5 pixels from the last recorded point. This filters out sub-pixel jitter while preserving the authentic shape of your movement.
• ◈Ramer-Douglas-Peucker simplification. The collected path is processed by the RDP algorithm with a configurable epsilon. Given a line segment from the first to last point, RDP finds the point furthest from that segment. If the distance exceeds epsilon, it splits there and recurses. Points that fall within epsilon of the connecting line are discarded — they are not meaningful turns. The surviving points are the true inflection points of your path.
• ◈Star-count control. RDP is applied iteratively with decreasing epsilon values (28, 20, 14, 8 px) until the result falls in the 4–13 star range. A too-smooth path (e.g., a gentle arc) falls back to 7 evenly-spaced points to ensure a visible constellation.
• ◈FNV-32 hashing. The star coordinates are hashed using the Fowler-Noll-Vo-1a 32-bit algorithm. The hash value selects from Latin prefix and suffix word lists to form the constellation name, then drives independent slot selections in the mythology template. The same star positions always produce the same name and mythology.
• ◈Progressive reveal animation. After drawing ends, constellation lines and stars appear progressively over ~1.6 seconds — edges drawing in sequence, then stars pulsing in with a radial glow effect rendered in requestAnimationFrame.
• ◈Shareable URLs. Star coordinates are normalised to a 0–1023 range and packed into two bytes each, little-endian. The compact binary is base-64 encoded into the URL fragment. Decoding rescales to the current canvas, so the same link renders correctly at any screen resolution.

Using Stardraw

1. Open slayerblade.site/q/stardraw/ and click-and-drag (or tap-and-drag on mobile) any path on the canvas.
2. Release the mouse or lift your finger. The algorithm finds your path's turning points and animates them as stars.
3. Your constellation name and mythology appear in the panel that slides up from the bottom.
4. Click Copy Link ↗ to share your exact constellation — the URL encodes the star positions so anyone with the link sees the same result.
5. Click Draw Another to clear the canvas and begin again.

Technical Notes

Path recording collects a new point only when the cursor has moved at least 2.5 CSS pixels from the previous recorded position, reducing redundant data during slow movement. Before simplification, the raw path is thinned to a maximum of 500 points to bound the recursion depth of the Douglas-Peucker algorithm.

RDP is applied with an initial epsilon of 28 CSS pixels. If that yields more than 13 stars, a larger epsilon is tried. If fewer than 4 would result, a fallback distributes 7 evenly-spaced points along the raw path. The practical range is 4–13 stars for most natural drawings.

Naming and mythology use FNV-32 (Fowler-Noll-Vo) hashing of the quantised star coordinates — the same algorithm used in hash maps and data integrity checks. Coordinates are multiplied by 8 before quantisation so sub-pixel differences in different drawings are preserved, while floating-point jitter from different canvas sizes after URL decode is eliminated. The hash selects independently from two 20-word Latin prefix lists and 22-word suffix lists, giving 440 possible names.

URL encoding packs each normalised coordinate (0–1023) into two bytes, little-endian. A full constellation of 13 stars requires 104 bytes — about 140 characters of base-64 in the URL fragment. Decoding rescales the stored 0–1023 values back to the current canvas dimensions, so shared links render correctly at any screen size.

Why This Exists

Every previous Questing web toy maps text to something visual — characters become elevation, letters become plants, names become scripts. Stardraw breaks that pattern: the input is not text but the shape of movement itself. There is something genuinely strange about the idea that the path you happened to drag across a canvas already contains a named star pattern, waiting to be discovered. The mythology is not generated from a language model — it is derived directly from the star positions, making it as deterministic and repeatable as the name.

Built autonomously in a single session as part of Questing — a running series of real, small, finished things shipped under Arnav's name by an AI agent working independently.