navmesh/src/map-parsers/build-polys-from-grid-map.test.ts

A library for fast pathfinding using navigation meshes in JS

import buildPolysFromGridMap from "./build-polys-from-grid-map";

describe("buildPolysFromGridMap", () => {
  it("should return an empty array when passed in no walkable tiles", () => {
    const polys = buildPolysFromGridMap([
      [0, 0, 0],
      [0, 0, 0],
      [0, 0, 0],
    ]);
    expect(polys).toEqual([]);
  });

  it("should return one polygon for a grid of all walkable tiles", () => {
    const polys = buildPolysFromGridMap([
      [1, 1, 1],
      [1, 1, 1],
      [1, 1, 1],
    ]);
    expect(polys.length).toBe(1);
  });

  it("should return two polygons for a grid of two simple rectangular islands", () => {
    const polys = buildPolysFromGridMap([
      [0, 0, 0, 0, 1, 1],
      [1, 1, 1, 0, 1, 1],
      [1, 1, 1, 0, 1, 1],
      [1, 1, 1, 0, 1, 1],
      [0, 0, 0, 0, 1, 1],
    ]);
    expect(polys.length).toBe(2);
  });

  it("should return 15 polygons for a grid with 15 1x1 islands", () => {
    const polys = buildPolysFromGridMap([
      [1, 0, 1, 0, 1, 0, 1, 0, 1, 0],
      [0, 1, 0, 1, 0, 1, 0, 1, 0, 1],
      [1, 0, 1, 0, 1, 0, 1, 0, 1, 0],
    ]);
    expect(polys.length).toBe(15);
  });

  it("should return scale polygons based on given tile width and height", () => {
    const tileWidth = 20;
    const tileHeight = 40;
    const grid = [
      [1, 1],
      [1, 1],
    ];
    const polys = buildPolysFromGridMap(grid, tileWidth, tileHeight);
    const topLeft = { x: 0, y: 0 };
    const bottomRight = { x: tileWidth * 2, y: tileHeight * 2 };
    expect(polys[0]).toContainEqual(topLeft);
    expect(polys[0]).toContainEqual(bottomRight);
  });
});