uplot-vplugins/Source/Utils/@Ext/Distr.ts

Plugins for uPlot, by Venryx.

function roundDec(val, dec) {
	return Math.round(val * (dec = 10 ** dec)) / dec;
}

export const SPACE_BETWEEN = 1;
export const SPACE_AROUND = 2;
export const SPACE_EVENLY = 3;

const coord = (i, offs, iwid, gap)=>roundDec(offs + i * (iwid + gap), 6);

export function distr(numItems, sizeFactor, justify, onlyIdx, each) {
	const space = 1 - sizeFactor;

	let gap = (
		justify == SPACE_BETWEEN ? space / (numItems - 1) :
		justify == SPACE_AROUND ? space / (numItems) :
		justify == SPACE_EVENLY ? space / (numItems + 1) : 0
	);

	if (isNaN(gap) || gap == Infinity) gap = 0;

	const offs = (
		justify == SPACE_BETWEEN ? 0 :
		justify == SPACE_AROUND ? gap / 2 :
		justify == SPACE_EVENLY ? gap : 0
	);

	const iwid = sizeFactor / numItems;
	const _iwid = roundDec(iwid, 6);

	if (onlyIdx == null) {
		for (let i = 0; i < numItems; i++) each(i, coord(i, offs, iwid, gap), _iwid);
	} else each(onlyIdx, coord(onlyIdx, offs, iwid, gap), _iwid);
}