Magical gene / lines and strokes

Lace

A thread-fine net of white veining over the horse - lace, or a crazed glaze, rather than the broad blotches of Marble Tobiano. A third allele carries the same marking worked in greys instead of white - dark where the pale form is light, and the same number of steps.

What it can come out as

Outcome	Carrying
Lace	`Lac/Lac` · `Lac/Lah` · `Lac/n` · `Lac/Lak`
Lace, black	`Lak/Lak` · `Lak/Lah` · `Lak/n`
Lace, coloured	`Lah/Lah`
Wild type	`Lah/n` · `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 1,786 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
`Lac/Lac`	Lace	0.002% — 1 in 50,000
`Lac/Lak`	Lace	0.0027% — 1 in 37,495
`Lac/Lah`	Lace	0.0027% — 1 in 37,495
`Lac/n`	Lace	0.038% — 1 in 2,632
`Lak/Lak`	Lace, black	0.0027% — 1 in 37,495
`Lak/Lah`	Lace, black	0.0027% — 1 in 37,495
`Lak/n`	Lace, black	0.0027% — 1 in 37,495
`Lah/Lah`	Lace, coloured	0.0027% — 1 in 37,495
`n/n`	Wild type	99.944%

Its gene carrot

The file

common/src/main/resources/horsegenetics/genes/lace.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.lace`
Phase	magical — it adds signed colour in phase 3, after the pigment has resolved
Priority	377 — where it sits in the one `(priority, key)` paint order
Alleles	`Lac` · `Lak` · `Lah` · `n`
Varies per horse	7 values drawn once off the expressing allele copy, so a foal that inherits the copy inherits the look
Built from	CRACKLE, TOWARD

Why it is built this way

Imported from the magic-gene intake, 2026-09-08 (from the second Marble Tobiano sketch, which asked to be a distinct locus rather than an allele). The fine net is kept off the legs on purpose - a leg is four units wide, and two crackle nets on it resolve as a wash rather than as lace.

The black allele is the white one with the light taken out of it, and it sits one rung under white in the dominance series - so every combination that existed before it keeps the outcome it had, and only the pairs carrying Lak are new. The re-toning is a mapping rather than a repaint: every achromatic target moves into the dark end of the scale keeping its order and its spacing, and every SATURATED one is left alone, because that colour is the gene rather than its lightness.

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.

Lace

Two crackle nets at different cell sizes, both drawn as the channels rather than the cells, so what you get is line rather than patch. The finer of the two runs over the barrel, the neck and the head only - the legs keep the coarse net alone, which stops the pattern turning to a wash where the parts are narrow.

the lace ground - a fine net over most of the horse — CRACKLE inverted, painted with TOWARD
a second, tighter net threaded through the first — CRACKLE inverted, painted with TOWARD

Lace, black

The same marking as the white form with the light taken out of it: a single near-black tone.

the lace ground - a fine net over most of the horse — CRACKLE inverted, painted with TOWARD
a second, tighter net threaded through the first — CRACKLE inverted, painted with TOWARD

Lace, coloured

The same two nets in a colour the line carries. Fully recessive.

the lace ground - a fine net over most of the horse — CRACKLE inverted, painted with TOWARD
a second, tighter net threaded through the first — CRACKLE inverted, painted with TOWARD

Wild type

No lace.

Paints nothing.