Natural gene / body size

LCORL / NCAPG (height)

Body height — the larger of the two size loci, and the first gene in this mod that changes how big a horse is without touching a pixel of its coat.

What it does

What it does: makes the horse taller. It is the larger of the two size genes and it changes nothing about the coat — a tall horse and a short one can be identical in colour.

Pair it against HMGA2, the pony gene, which pulls the other way.

Crossing two of them

Its gene carrot

A server may switch the resizing off

This locus is one of the ones that moves a horse’s size, and vanilla scales the hitbox from the model — so a world that would rather have tack and hitboxes sit exactly where vanilla puts them can set body.size false. The gene is still inherited, still reported and still worth breeding for; only the entity is held at 1.0×.

Gene key
horsegenetics.lcorl
Priority
84
Alleles
L n
Outcomes
lcorl-tall, lcorl-mixed, lcorl-plain
Coat effect
none — every outcome is a wild type
Default allele
n
Wild population
p(L) = 0.30
Founder draws
1 × nextFloat()
Catalogue entries
1 — it never changes what a horse looks like
It paints nothing, and that is what makes it free

Every combination of this gene is an expression marked wildType. That reads oddly for a gene that can change how big a horse is or kill a foal, and it is exactly right: wildType means changes nothing about the coat. Because none of the non-coat genes paints, Gene.affectsCoat() is false for all of them, they are left out of a horse’s texture key, and the genotype gallery collapses the whole locus into one entry however many alleles it has. What the gene actually does travels on the trait system instead.

The combination table

combination outcome scale speed jump
L/Llcorl-tall+0.10+0.020+0.04
L/nlcorl-mixed+0.05+0.010+0.02
n/nlcorl-plain
Answered: how size is drawn

The roadmap flagged the entity-scale path as unverified, check before designing. It is verified: Attributes.SCALE exists in 26.1.2, it is on the attribute supplier of every living entity (LivingEntity.createLivingAttributes), and vanilla scales the model and the hitbox from it. So the whole size system is one attribute write in HorseRecords.applyTraitsToEntity — no renderer-side scaling, no hand-written hitbox change, and a pony is genuinely a smaller target.

Why it also moves speed and jump

A taller horse covers more ground per stride and clears more. Those side effects are what stop the size loci being pure decoration, and they are what makes HMGA2’s pony allele a real trade rather than a strict downgrade.

Between this and HMGA2 the healthy size range runs from about 0.88 to 1.10 of a vanilla horse. The dwarfism loci reach further down by multiplying rather than subtracting — see the trait system for why that composition matters.

Source: common/genetics/genes/LcorlGene.java