Magical gene / fields and regions

Morpho Wing

A patch of iridescent light gathers low on the haunch like a wing folded against the flank, cut through with dark bars that rake toward the tail. 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
Morpho Wing, pale	`Mow/Mow` · `Mow/Moc` · `Mow/n` · `Mow/Mok`
Morpho Wing, black	`Mok/Mok` · `Mok/Moc` · `Mok/n`
Morpho Wing, coloured	`Moc/Moc`
Wild type	`Moc/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 3,572 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
`Mow/Mow`	Morpho Wing, pale	0.001% — 1 in 100,000
`Mow/Mok`	Morpho Wing, pale	0.0013% — 1 in 75,019
`Mow/Moc`	Morpho Wing, pale	0.0013% — 1 in 75,019
`Mow/n`	Morpho Wing, pale	0.019% — 1 in 5,263
`Mok/Mok`	Morpho Wing, black	0.0013% — 1 in 75,019
`Mok/Moc`	Morpho Wing, black	0.0013% — 1 in 75,019
`Mok/n`	Morpho Wing, black	0.0013% — 1 in 75,019
`Moc/Moc`	Morpho Wing, coloured	0.0013% — 1 in 75,019
`n/n`	Wild type	99.972%

Its gene carrot

The file

common/src/main/resources/horsegenetics/genes/morpho_wing.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.morpho_wing`
Phase	magical — it adds signed colour in phase 3, after the pigment has resolved
Priority	278 — where it sits in the one `(priority, key)` paint order
Alleles	`Mow` · `Mok` · `Moc` · `n`
Varies per horse	1 value drawn once off the expressing allele copy, so a foal that inherits the copy inherits the look
Built from	FAN, PARTS, PATH, TOWARD, emissive

Why it is built this way

The bars are a FAN, and FAN exists because of this gene. The reference's bars share a common origin near the body and both widen and turn as they travel out from it; WAVES takes its phase from a straight line, so its bars are parallel, evenly spaced and all pointed the same way everywhere in the region, whatever its wavelength. That is a different measurement, not different tuning, and it is the one the mask was added for.

Both layers re-declare the same PARTS and PATH region rather than the second reading the first's paint - a layer cannot see what the layer above it painted.

FAN's spacing is an ANGLE - the arc one cycle covers a single body unit from the pivot - so the bars here are 0.17, not the 1.5 that reads like 'one and a half units apart'. At 1.5 the whole patch is inside one bar. It is the one number on this gene worth checking against a render rather than against intuition.

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 Mok 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.

Morpho Wing, pale

A soft silver-white sheen pools low on the haunch, banded with a few dark bars raking back toward the tail.

the wing — PARTS × PATH, painted with TOWARD, and it glows
and the bars across it — PARTS × PATH × FAN, painted with TOWARD

Morpho Wing, black

The same marking as the white form with the light taken out of it: the same 2 steps, moved to the dark end of the scale.

the wing — PARTS × PATH, painted with TOWARD, and it glows
and the bars across it — PARTS × PATH × FAN, painted with TOWARD

Morpho Wing, coloured

The same folded wing, but the light in it is the colour this line of horses runs to - still barred in black.

the wing — PARTS × PATH, painted with TOWARD, and it glows
and the bars across it — PARTS × PATH × FAN, painted with TOWARD

Wild type

Nothing.

Paints nothing.