var fn = `Math.min(${fn},Math.min(Y-0,${size}-Y))`
var fn = `Math.min(${fn},Math.min(Z-0,${size}-Z))`
for (var d = 0; d < depth; ++d) {
var fn = `Math.min(${fn},-Math.min(Math.min((Math.pow(3,${d})*X/${size})%1-1/3,2/3-(Math.pow(3,${d})*X/${size})%1),Math.min((Math.pow(3,${d})*Y/${size})%1-1/3,2/3-(Math.pow(3,${d})*Y/${size})%1)))`
var fn = `Math.min(${fn},-Math.min(Math.min((Math.pow(3,${d})*X/${size})%1-1/3,2/3-(Math.pow(3,${d})*X/${size})%1),Math.min(Math.min((Math.pow(3,${d})*Y/${size})%1-1/3,2/3-(Math.pow(3,${d})*Y/${size})%1),Math.min((Math.pow(3,${d})*Z/${size})%1-1/3,2/3-(Math.pow(3,${d})*Z/${size})%1))))`