@antv/g2
Version:
the Grammar of Graphics in Javascript
79 lines • 2.79 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.OverlapDodgeY = void 0;
const d3_array_1 = require("d3-array");
function isSegmentIntersect([a, b], [c, d]) {
return d > a && b > c;
}
function useMap() {
const map = new Map();
const get = (key) => map.get(key);
const set = (key, value) => map.set(key, value);
return [get, set];
}
function getBoundsWithoutConnector(shape) {
const node = shape.cloneNode(true);
const connectorShape = node.getElementById('connector');
connectorShape && node.removeChild(connectorShape);
const { min, max } = node.getRenderBounds();
node.destroy();
return { min, max };
}
/**
* An iterative dodge method avoids label overlap. (n * log(n))
*/
const OverlapDodgeY = (options) => {
const { maxIterations = 10, maxError = 0.1, padding = 1 } = options;
return (labels) => {
const n = labels.length;
if (n <= 1)
return labels;
// Index y, x0, x, height, by label.
const [y0, setY0] = useMap();
const [y, setY] = useMap();
const [h, setH] = useMap();
const [xx, setXX] = useMap();
for (const label of labels) {
const { min, max } = getBoundsWithoutConnector(label);
const [x0, y0] = min;
const [x1, y1] = max;
setY0(label, y0);
setY(label, y0);
setH(label, y1 - y0);
setXX(label, [x0, x1]);
}
// Offsets position Y.
for (let iter = 0; iter < maxIterations; iter++) {
labels.sort((a, b) => (0, d3_array_1.ascending)(y(a), y(b)));
let error = 0;
for (let i = 0; i < n - 1; i++) {
const l0 = labels[i];
let j = i + 1;
let l1;
// Find the next label overlapping with the current label in x direction.
while ((l1 = labels[j]) && !isSegmentIntersect(xx(l0), xx(l1)))
j += 1;
if (l1) {
const y0 = y(l0);
const h0 = h(l0);
const y1 = y(l1);
const delta = y1 - (y0 + h0);
if (delta < padding) {
const newDelta = (padding - delta) / 2;
error = Math.max(error, newDelta);
setY(l0, y0 - newDelta);
setY(l1, y1 + newDelta);
}
}
}
if (error < maxError)
break;
}
for (const label of labels) {
label.style.y += y(label) - y0(label);
}
return labels;
};
};
exports.OverlapDodgeY = OverlapDodgeY;
//# sourceMappingURL=overlapDodgeY.js.map