Serpentine

What it can come out as

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 893 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.

Its gene carrot

The file

common/src/main/resources/horsegenetics/genes/serpentine.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.

Why it is built this way

The source was an SVG: twelve posterised colours traced off a photograph of a cut mineral slab, about 210 KB of path data across thirteen layers. A field, not an outline - rebuilt as a rule.

Reading of the source: long bands running the length of the slab, muted and close in value, each pair separated by a much darker seam; a slate wash drifting across the whole thing independently of the bands; and bright green mineral scattered through it in two grades, coarse chips and fine dust.

The bands are STROKES rather than STRIPES. STRIPES gives parallel bands with an even pitch, which is a zebra; these wander, vary in width along their run and pinch out, and that is what the level set of a noise field does. Three fields on three seeds so the sage, the blue-grey and the seams do not sit on top of each other.

width against spacing is the constraint. 1.4 on a spacing that bottoms out at 3.2 is a ratio of 0.44, and the seams at 0.7 on 5.2 are far under - the seams have to stay thin because they are the only high-contrast element and a wash of them would eat the bands. Zebra's Coat is the standing lesson: ten wide on a three pitch and it rendered as a solid white neck.

The ore is two SPECKLEs on different seeds and different spacings, not one. A single scatter at one size reads as noise; a coarse grade at 1.1 and a fine one at 0.8, each with its own clumping drift, reads as mineral - which is a fact about grain rather than about density.

The slate drift and the stone ground share $mistSeed at different scales on purpose: the pale ground and the violet wash then pool in the same places, which is what stops the wash reading as a separate marking laid over the top.

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.

Serpentine

Streaky bands of taupe, sage and blue-grey run the length of the coat, seamed with dark red-brown, with bright green ore scattered through them.

1. the stone ground — NOISE, painted with TOWARD
2. the sage bands — STROKES, painted with TOWARD
3. the blue-grey bands — STROKES, painted with TOWARD
4. the slate drift — NOISE, painted with TOWARD
5. the dark seams between bands — STROKES, painted with TOWARD
6. the ore, coarse chips — SPECKLE, painted with TOWARD
7. the ore, fine dust — SPECKLE, painted with TOWARD

Coloured ore

The same stone, with the ore running a colour this line of horses carries instead of green.

The recessive coloured half of the usual pair, and the only thing it moves is the ore. The stone stays stone: its five colours are a value structure in muted earth, and putting a hue knob on them makes a horse the colour of a highlighter rather than a horse cut out of rock. The two ore grades share one hue and differ in lightness, 0.62 and 0.82, so the fine dust still reads as a paler grade of the same mineral.

1. the stone ground — NOISE, painted with TOWARD
2. the sage bands — STROKES, painted with TOWARD
3. the blue-grey bands — STROKES, painted with TOWARD
4. the slate drift — NOISE, painted with TOWARD
5. the dark seams between bands — STROKES, painted with TOWARD
6. the ore, coarse chips — SPECKLE, painted with TOWARD
7. the ore, fine dust — SPECKLE, painted with TOWARD

Wild type

Unmarked.

Paints nothing.