Magical gene / spots and rings

Ocular

Eyes down the horse's neck - open ones, with a white, an iris in the line's own colour and a pupil. They are drawn off a single lattice, so every one of them is a real eye and not a smear that happens to be round.

What it can come out as

OutcomeCarrying
Many eyesOcu/Ocu
A few eyesOcu/n
Wild typen/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 5,000 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 pairShows asHow often
Ocu/OcuMany eyes0.001% — 1 in 100,000
Ocu/nA few eyes0.019% — 1 in 5,263
n/nWild type99.98%

Its gene carrot

The file

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

Keyhorsegenetics.ocular
Phasemagical — it adds signed colour in phase 3, after the pigment has resolved
Priority320 — where it sits in the one (priority, key) paint order
AllelesOcu · n
Varies per horse7 values drawn once off the expressing allele copy, so a foal that inherits the copy inherits the look
Built fromSPOTS, TOWARD

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.

Many eyes

Two copies, and the neck is crowded with them - most of the lattice carries an eye. Each is built from one cell of a single scatter, drawn four times at shrinking radius: a darker socket, the white, the iris and the pupil, concentric because they are the same cell rather than because anything lined them up. The iris colour is the horse's own and travels with the copy, so a line of these breeds an eye colour the way an ordinary line breeds a coat.

  1. the socket the lid sits in, a shade darker than the coat — SPOTS, painted with TOWARD
  2. the white of the eye — SPOTS, painted with TOWARD
  3. the iris — SPOTS, painted with TOWARD
  4. the pupil — SPOTS, painted with TOWARD

A few eyes

One copy. The same eyes, in the same places, but only about a third of the lattice carries one - a handful down the crest rather than a covering. The locus is dose-dependent rather than recessive: a single copy is visible, and a breeder can tell a carrier from a homozygote by counting.

  1. the socket the lid sits in, a shade darker than the coat — SPOTS, painted with TOWARD
  2. the white of the eye — SPOTS, painted with TOWARD
  3. the iris — SPOTS, painted with TOWARD
  4. the pupil — SPOTS, painted with TOWARD

Wild type

The horse has the usual number of eyes.

Paints nothing.