site/node_modules/d3-hierarchy/src/treemap/squarify.js
2024-10-14 08:09:33 +02:00

67 lines
1.8 KiB
JavaScript

import treemapDice from "./dice.js";
import treemapSlice from "./slice.js";
export var phi = (1 + Math.sqrt(5)) / 2;
export function squarifyRatio(ratio, parent, x0, y0, x1, y1) {
var rows = [],
nodes = parent.children,
row,
nodeValue,
i0 = 0,
i1 = 0,
n = nodes.length,
dx, dy,
value = parent.value,
sumValue,
minValue,
maxValue,
newRatio,
minRatio,
alpha,
beta;
while (i0 < n) {
dx = x1 - x0, dy = y1 - y0;
// Find the next non-empty node.
do sumValue = nodes[i1++].value; while (!sumValue && i1 < n);
minValue = maxValue = sumValue;
alpha = Math.max(dy / dx, dx / dy) / (value * ratio);
beta = sumValue * sumValue * alpha;
minRatio = Math.max(maxValue / beta, beta / minValue);
// Keep adding nodes while the aspect ratio maintains or improves.
for (; i1 < n; ++i1) {
sumValue += nodeValue = nodes[i1].value;
if (nodeValue < minValue) minValue = nodeValue;
if (nodeValue > maxValue) maxValue = nodeValue;
beta = sumValue * sumValue * alpha;
newRatio = Math.max(maxValue / beta, beta / minValue);
if (newRatio > minRatio) { sumValue -= nodeValue; break; }
minRatio = newRatio;
}
// Position and record the row orientation.
rows.push(row = {value: sumValue, dice: dx < dy, children: nodes.slice(i0, i1)});
if (row.dice) treemapDice(row, x0, y0, x1, value ? y0 += dy * sumValue / value : y1);
else treemapSlice(row, x0, y0, value ? x0 += dx * sumValue / value : x1, y1);
value -= sumValue, i0 = i1;
}
return rows;
}
export default (function custom(ratio) {
function squarify(parent, x0, y0, x1, y1) {
squarifyRatio(ratio, parent, x0, y0, x1, y1);
}
squarify.ratio = function(x) {
return custom((x = +x) > 1 ? x : 1);
};
return squarify;
})(phi);