Magical gene / no coat effect

Singer

Occasionally, and without warning, the horse plays music. Which record depends on the allele; how long and how loud are written on the allele copy. It plays the opening and then stops — which is the part you would recognise anyway.

Built, and not yet seen in game

The gene, its inheritance and its founder table exist and are covered by the test suite; the translator that turns it into behaviour was written against the 26.1.2 sources and is flagged unverified in its own comments. Nothing on this page has been watched happening to a horse. What to look at, and what is most likely to be wrong, is on To be verified.

What it does

CombinationOutcome
two copies of one alleleplays the opening of that record, now and then
two different allelesnothing
anything with an nnothing

Why only the opening

A record in Minecraft is one long sound that can only be played from its beginning. There is no way to start in the middle, so “a section” can only ever mean the first few seconds. The duration is epigenetic, so a line can be bred toward a longer excerpt.

Health

None.

Gene key
horsegenetics.singer
Alleles
one per music disc, plus n
Inheritance
homozygous recessive, matched pair
Reaches the game as
a sound effect with a stop
Epigenetic
duration and volume
Coat effect
none, ever
A herd of singers is an audio denial-of-service

Sound is cheap per firing and unbearable in aggregate. Several expressing horses in one pasture will overlap constantly, and there is no volume setting that fixes it. One at a time per area, with a cooldown — the arbitration is part of the gene, not a refinement.

Stopping a sound needs a per-listener packet

Playing is a one-shot; stopping partway is a stop-sound packet sent to everyone who can hear it. Cheap, but it is client state, so a listener who arrives mid-track and one who leaves must both end up correct.

Disc ids from other mods resolve live

Following lycan: a disc this game version has never heard of falls silent rather than erroring. An allele for a modded disc is legal and simply does nothing without that mod.

An engine limit written into the design

The original specification said “plays sections of a disc”, which is not possible. Rather than approximate it with note-block phrases — considered, and rejected because referencing music people already know is most of the charm — the gene takes the limit as its shape: the opening, for an epigenetic length. Recorded here so the impossible version is not attempted again.

Deliberately frivolous

It does nothing useful and it is not meant to. The magical side of the mod is allowed a few loci whose entire return is that they are funny to breed for, and a horse that will not stop playing Cat is one of them.

Planned source: common/genetics/genes/SingerGene.java