Natural gene / performance

RYR2 (jumping)

Jumping ability — the locus that moves a stat nothing in this mod tracked before. Each J copy is worth 0.09 jump strength on a baseline of 0.50.

What it does

What it does: makes the horse jump higher, and nothing else. It is the only gene that touches jump.

Two copies are worth noticeably more than one, so it is worth breeding to fix.

Crossing two of them

Its gene carrot

Gene key
horsegenetics.ryr2
Priority
83
Alleles
J n
Outcomes
jumper, jumper-mixed, jumper-plain
Coat effect
none — every outcome is a wild type
Default allele
n
Wild population
p(J) = 0.20
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 jump strength
J/Jjumper+0.18
J/njumper-mixed+0.09
n/njumper-plain

Why jump strength exists now and did not before

Jump strength was on the “not tracked yet” list for as long as the stats were a random roll off the parents, because there was nothing sensible to roll it from. With the body resolved out of the genotype it costs one gene and one attribute write, and it gives a breeding programme a third axis to trade against speed.

The two size loci nudge it in both directions as well — a tall horse clears more and a pony clears less — so the range across the whole model runs about 0.46 to 0.72, inside vanilla’s 0.40.8.

Source: common/genetics/genes/Ryr2Gene.java