SurfacePointtype

A point of the Earth's surface as one picture shows it: where it falls (CSS pixels in the box), which way is straight up from the ground there on the screen (upX, upY: a direction whose length is how much of an upright stick the reader sees, 0 looking straight down on it and 1 seeing it side on) and facing, the cosine between the ground's upright and the way to the camera (above 0 the point faces the reader, at or below it is on the far side).

import type { SurfacePoint } from "@johnmorrisdotca/chikyu-earth/markers";

interface SurfacePoint {
    x: number;
    y: number;
    upX: number;
    upY: number;
    facing: number;
}

import type { SurfacePoint } from "@johnmorrisdotca/chikyu-earth/markers";

const middle: SurfacePoint = { x: 210, y: 210, upX: 0, upY: 0, facing: 1 };
console.log(middle.facing);

1