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Chikyu Earth地球

A line-drawn globe of the world's countries that turns at the Earth's own rate, with an optional realistic Earth from space and markers for any place.

Chikyu is the Japanese word 地球 for the Earth. About the name

Contents

Reference · The realistic Earth's pure parts

TilePerspectivetype

A camera that sees the Earth in perspective, from a place that can be a few kilometres above the ground, in the Earth's own axes (x toward longitude 90, y north, z toward longitude 0; the Earth's radius is 1).

Import it

import type { TilePerspective } from "@johnmorrisdotca/chikyu-earth/realistic";

Definition

interface TilePerspective {
    eye: readonly [
        number,
        number,
        number
    ];
    project(point: readonly [
        number,
        number,
        number
    ]): {
        x: number;
        y: number;
    } | null;
    ground(x: number, y: number): readonly [
        number,
        number,
        number
    ] | null;
}

Members

NameTypeDescription
eyereadonly [number, number, number]

Where the camera is.

project(point: readonly [number, number, number]): { x: number; y: number; } | null

Where a point of the Earth's surface falls in the box (CSS pixels), or null where it is behind the camera.

ground(x: number, y: number): readonly [number, number, number] | null

The point of the Earth's surface under a place in the box (a unit vector), or null where the box shows the sky.

Examples

import type { TilePerspective } from "@johnmorrisdotca/chikyu-earth/realistic";

const look: TilePerspective = { eye: [0, 0, 1.0235], project: (p) => ({ x: 400 + p[0] * 5000, y: 300 - p[1] * 5000 }), ground: () => [0, 0, 1] };
console.log(look.eye);
[ 0, 0, 1.0235 ]

What it prints (run when this page was built)

View sourceEdit on GitHubMade from the source of @johnmorrisdotca/chikyu-earth 0.51.1.