regionBox関数

A window tight on one region, for drawing it on its own.

Two things decide it, and getting either wrong draws a country instead of a shape. The room around the region is a fraction of that side of it, not of its longest side. And the window takes the shape of the frame it will be drawn in (aspect, how much wider than tall), because an SVG scaled to fit keeps its window's proportions and fills the rest of the frame with whatever is next to it. With both right the region fills the side that limits it, and the room left over falls on the other side, where it does what the room was for: the neighbours show in outline, so it is a place rather than a blob. Framed where it is drawn, so a region in an inset is framed there.

import { regionBox } from "@johnmorrisdotca/chizu";

function regionBox(map: Frameable, code: string | number, aspect?: number): MapBox

import WORLD from "@johnmorrisdotca/chizu/world";
import { boxToViewBox, regionBox } from "@johnmorrisdotca/chizu";

const box = regionBox(WORLD, "IT", 4 / 3);
console.log((box.width / box.height).toFixed(3));
// 1.333

1.333