const digits = /-?\d+\.?\d*/g;
export function extractNum(string) {
return string.replace(/\D/g,'');
}
export function getTracked(trackedAndTrackerEls) {
const sorted = [...trackedAndTrackerEls]
.sort((a, b) => a.id < b.id || extractNum(a.id) <= extractNum(b.id));
const groups = [];
const els = sorted.slice();
while (els.length) {
groups.push([els.pop(), els.pop()]);
}
return groups;
}
export function track(targetEl, trackingEl, transformMtx) {
let x = targetEl.getAttributeNS(null, 'x');
let y = targetEl.getAttributeNS(null, 'y');
let ptBefore = new DOMPoint(x, y);
let ptAfter = ptBefore.matrixTransform(transformMtx);
trackingEl.setAttributeNS(null, 'x', ptAfter.x);
trackingEl.setAttributeNS(null, 'y', ptAfter.y);
}
export default function getComputedTransformMatrix(el) {
const matrixSequence = getComputedStyle(el).transform.match(digits),
identityMatrix = '';
return new DOMMatrix(matrixSequence || identityMatrix);
}