Magical gene / lines and strokes

Lacevein

Fine branching lace etches across the coat, rooted in two deep jewel-toned blooms at the withers and the poll.

What it can come out as

Outcome	Carrying
Lacevein	`Lvn/Lvn`
Lacevein, sparse	`Lvn/n`
Wild type	`n/n`

How each one is actually drawn - region by region, and the layers it is built from - is on the coding tab.

Crossing two of them

Finding one

About 1 in 2,500 wild horses is born showing this. That is the whole of the supply: catch one, or make one with the carrot below. Breeds set their own pools and a breed built around this gene will carry it far more often than the wild population does.

Wild pair	Shows as	How often
`Lvn/Lvn`	Lacevein	0.002% — 1 in 50,000
`Lvn/n`	Lacevein, sparse	0.038% — 1 in 2,632
`n/n`	Wild type	99.96%

Its gene carrot

The file

common/src/main/resources/horsegenetics/genes/lacevein.json — a data-driven gene, not a Java class. It is listed in the index.json beside it and registered by Genes' class initialiser at startup.

Key	`horsegenetics.lacevein`
Phase	magical — it adds signed colour in phase 3, after the pigment has resolved
Priority	384 — where it sits in the one `(priority, key)` paint order
Alleles	`Lvn` · `n`
Varies per horse	3 values drawn once off the expressing allele copy, so a foal that inherits the copy inherits the look
Built from	FRACTAL, PARTS, PATH, TOWARD

Why it is built this way

Named Lacevein rather than Lace: there is already a gene called Lace, and two entries a letter apart in the same list is a trap for whoever reads the genotype next.

The heterozygote is not a thinner version of the homozygote - it covers fewer PARTS and runs two octaves at a higher threshold, so it reads as a smaller, simpler marking rather than a faded one, and it carries one bloom instead of two.

The lace and the blooms are co-located, not connected. The reference shows veins BRANCHING OUT of the two deep centres, and nothing in this vocabulary measures connectivity back to a root: a ridged FRACTAL is unrooted global noise and a PATH carries one prescribed curve, so a vein here will sometimes pass near a bloom without visibly joining it. That is a different question - 'is this texel joined by an unbroken branch to that point' - and it is not a threshold away from any of the masks that exist.

What it paints

Each outcome, described the way the gene file describes it, and then the layers that draw it in the order they are painted. The prose is the part a reader checks a bake against; the list underneath is what the engine actually did.

Lacevein

Dense black lace forks and tapers across the body, neck, head and muzzle, rooted in two deep jewel-toned blooms at the withers and poll.

the lace — PARTS × FRACTAL, painted with TOWARD
the bloom at the withers — PATH, painted with TOWARD
and the bloom at the poll — PATH, painted with TOWARD

Lacevein, sparse

A sparser web of black lace crosses the body and neck, fading around a single faint bloom at the withers.

the lace — PARTS × FRACTAL, painted with TOWARD
and one faint bloom — PATH, painted with TOWARD

Wild type

Nothing.

Paints nothing.