@bokeh/bokehjs
Version:
Interactive, novel data visualization
105 lines • 3.83 kB
JavaScript
export function point_in_poly(x, y, px, py) {
let inside = false;
let x1 = px[px.length - 1];
let y1 = py[py.length - 1];
for (let i = 0; i < px.length; i++) {
const x2 = px[i];
const y2 = py[i];
if ((y1 < y) != (y2 < y)) {
if ((x1 + (y - y1) / (y2 - y1) * (x2 - x1)) < x) {
inside = !inside;
}
}
x1 = x2;
y1 = y2;
}
return inside;
}
export function point_in_ellipse(x, y, angle, b, a, x0, y0) {
const A = ((Math.cos(angle) / a) ** 2 + (Math.sin(angle) / b) ** 2);
const B = 2 * Math.cos(angle) * Math.sin(angle) * ((1 / a) ** 2 - (1 / b) ** 2);
const C = ((Math.cos(angle) / b) ** 2 + (Math.sin(angle) / a) ** 2);
const eqn = A * (x - x0) ** 2 + B * (x - x0) * (y - y0) + C * (y - y0) ** 2;
const inside = eqn <= 1;
return inside;
}
export function dist_2_pts(p0, p1) {
return (p0.x - p1.x) ** 2 + (p0.y - p1.y) ** 2;
}
export function dist_to_segment_squared(p, v, w) {
const l2 = dist_2_pts(v, w);
if (l2 == 0) {
return dist_2_pts(p, v);
}
const t = ((p.x - v.x) * (w.x - v.x) + (p.y - v.y) * (w.y - v.y)) / l2;
if (t < 0) {
return dist_2_pts(p, v);
}
if (t > 1) {
return dist_2_pts(p, w);
}
const q = { x: v.x + t * (w.x - v.x), y: v.y + t * (w.y - v.y) };
return dist_2_pts(p, q);
}
export function dist_to_segment(p, v, w) {
return Math.sqrt(dist_to_segment_squared(p, v, w));
}
export function check_2_segments_intersect(l0_x0, l0_y0, l0_x1, l0_y1, l1_x0, l1_y0, l1_x1, l1_y1) {
/*
* Check if 2 segments (l0 and l1) intersect. Returns a structure with
* the following attributes:
* * hit (boolean): whether the 2 segments intersect
* * x (float): x coordinate of the intersection point
* * y (float): y coordinate of the intersection point
*/
const den = ((l1_y1 - l1_y0) * (l0_x1 - l0_x0)) - ((l1_x1 - l1_x0) * (l0_y1 - l0_y0));
if (den == 0) {
return { hit: false, x: null, y: null };
}
else {
let a = l0_y0 - l1_y0;
let b = l0_x0 - l1_x0;
const num1 = ((l1_x1 - l1_x0) * a) - ((l1_y1 - l1_y0) * b);
const num2 = ((l0_x1 - l0_x0) * a) - ((l0_y1 - l0_y0) * b);
a = num1 / den;
b = num2 / den;
const x = l0_x0 + (a * (l0_x1 - l0_x0));
const y = l0_y0 + (a * (l0_y1 - l0_y0));
return { hit: (a > 0 && a < 1) && (b > 0 && b < 1), x, y };
}
}
// Given two polygons, is any vertex of one inside the other
export function vertex_overlap(x0, y0, x1, y1) {
// need to check "both directions" to handle total inclusion cases
for (let i = 0; i < x0.length; i++) {
if (point_in_poly(x0[i], y0[i], x1, y1)) {
return true;
}
}
for (let i = 0; i < x1.length; i++) {
if (point_in_poly(x1[i], y1[i], x0, y0)) {
return true;
}
}
return false;
}
// Given two polygons, do any pair of edges intersect
export function edge_intersection(x0, y0, x1, y1) {
for (let i = 0; i < x0.length - 1; i++) {
for (let j = 0; j < x1.length - 1; j++) {
if (check_2_segments_intersect(x0[i], y0[i], x0[i + 1], y0[i + 1], x1[j], y1[j], x1[j + 1], y1[j + 1]).hit) {
return true;
}
}
// consider x1, y1 "closing" segment
if (check_2_segments_intersect(x0[i], y0[i], x0[i + 1], y0[i + 1], x1[x1.length - 1], y1[x1.length - 1], x1[0], y1[0]).hit) {
return true;
}
}
// consider x0, y0, "closing" segment
if (check_2_segments_intersect(x0[x0.length - 1], y0[x0.length - 1], x0[0], y0[0], x1[x1.length - 1], y1[x1.length - 1], x1[0], y1[0]).hit) {
return true;
}
return false;
}
//# sourceMappingURL=hittest.js.map