@rxflow/manhattan/cjs/geometry/Line.js

Manhattan routing algorithm for ReactFlow - generates orthogonal paths with obstacle avoidance

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.Line = void 0;
var _Point = require("./Point");
/**
 * Line class representing a line segment
 */
class Line {
  start;
  end;
  constructor(start, end) {
    this.start = start;
    this.end = end;
  }

  /**
   * Calculate intersection points with a rectangle
   * Returns an array of intersection points
   */
  intersect(rect) {
    const intersections = [];

    // Define rectangle edges
    const edges = [
    // Top edge
    {
      p1: new _Point.Point(rect.x, rect.y),
      p2: new _Point.Point(rect.x + rect.width, rect.y)
    },
    // Right edge
    {
      p1: new _Point.Point(rect.x + rect.width, rect.y),
      p2: new _Point.Point(rect.x + rect.width, rect.y + rect.height)
    },
    // Bottom edge
    {
      p1: new _Point.Point(rect.x, rect.y + rect.height),
      p2: new _Point.Point(rect.x + rect.width, rect.y + rect.height)
    },
    // Left edge
    {
      p1: new _Point.Point(rect.x, rect.y),
      p2: new _Point.Point(rect.x, rect.y + rect.height)
    }];

    // Check intersection with each edge
    for (const edge of edges) {
      const intersection = this.lineIntersection(this.start, this.end, edge.p1, edge.p2);
      if (intersection) {
        intersections.push(intersection);
      }
    }
    return intersections;
  }

  /**
   * Calculate intersection point between two line segments
   * Returns null if lines don't intersect
   */
  lineIntersection(p1, p2, p3, p4) {
    const x1 = p1.x,
      y1 = p1.y;
    const x2 = p2.x,
      y2 = p2.y;
    const x3 = p3.x,
      y3 = p3.y;
    const x4 = p4.x,
      y4 = p4.y;
    const denom = (x1 - x2) * (y3 - y4) - (y1 - y2) * (x3 - x4);

    // Lines are parallel
    if (Math.abs(denom) < 1e-10) {
      return null;
    }
    const t = ((x1 - x3) * (y3 - y4) - (y1 - y3) * (x3 - x4)) / denom;
    const u = -((x1 - x2) * (y1 - y3) - (y1 - y2) * (x1 - x3)) / denom;

    // Check if intersection is within both line segments
    if (t >= 0 && t <= 1 && u >= 0 && u <= 1) {
      return new _Point.Point(x1 + t * (x2 - x1), y1 + t * (y2 - y1));
    }
    return null;
  }
}
exports.Line = Line;