@zenghawtin/graph2d/src/data_structures/de9im.js

Javascript library for 2d geometry

/*
    Dimensionally extended 9-intersected model
    See https://en.wikipedia.org/wiki/DE-9IM for more details
 */
// const DISJOINT = RegExp('FF.FF....');
const EQUAL = RegExp('T.F..FFF.|T.F...F..');
const INTERSECT = RegExp('T........|.T.......|...T.....|....T....');
const TOUCH = RegExp('FT.......|F..T.....|F...T....');
const INSIDE = RegExp('T.F..F...');
const COVERED = RegExp('T.F..F...|.TF..F...|..FT.F...|..F.TF...');

class DE9IM {
    /**
     * Create new instance of DE9IM matrix
     */
    constructor() {
        /**
         * Array representing 3x3 intersection matrix
         * @type {Shape[]}
         */
        this.m = new Array(9).fill(undefined);
    }

    /**
     * Get Interior To Interior intersection
     * @returns {Shape[] | undefined}
     */
    get I2I() {
        return this.m[0];
    }

    /**
     * Set Interior To Interior intersection
     * @param geom
     */
    set I2I(geom) {
        this.m[0] = geom;
    }

    /**
     * Get Interior To Boundary intersection
     * @returns {Shape[] | undefined}
     */
    get I2B() {
        return this.m[1];
    }

    /**
     * Set Interior to Boundary intersection
     * @param geomc
     */
    set I2B(geom) {
        this.m[1] = geom;
    }

    /**
     * Get Interior To Exterior intersection
     * @returns {Shape[] | undefined}
     */
    get I2E() {
        return this.m[2];
    }

    /**
     * Set Interior to Exterior intersection
     * @param geom
     */
    set I2E(geom) {
        this.m[2] = geom;
    }

    /**
     * Get Boundary To Interior intersection
     * @returns {Shape[] | undefined}
     */
    get B2I() {
        return this.m[3];
    }

    /**
     * Set Boundary to Interior intersection
     * @param geom
     */
    set B2I(geom) {
        this.m[3] = geom;
    }

    /**
     * Get Boundary To Boundary intersection
     * @returns {Shape[] | undefined}
     */
    get B2B() {
        return this.m[4];
    }

    /**
     * Set Boundary to Boundary intersection
     * @param geom
     */
    set B2B(geom) {
        this.m[4] = geom;
    }

    /**
     * Get Boundary To Exterior intersection
     * @returns {Shape[] | undefined}
     */
    get B2E() {
        return this.m[5];
    }

    /**
     * Set Boundary to Exterior intersection
     * @param geom
     */
    set B2E(geom) {
        this.m[5] = geom;
    }

    /**
     * Get Exterior To Interior intersection
     * @returns {Shape[] | undefined}
     */
    get E2I() {
        return this.m[6];
    }

    /**
     * Set Exterior to Interior intersection
     * @param geom
     */
    set E2I(geom) {
        this.m[6] = geom;
    }

    /**
     * Get Exterior To Boundary intersection
     * @returns {Shape[] | undefined}
     */
    get E2B() {
        return this.m[7];
    }

    /**
     * Set Exterior to Boundary intersection
     * @param geom
     */
    set E2B(geom) {
        this.m[7] = geom;
    }

    /**
     * Get Exterior to Exterior intersection
     * @returns {Shape[] | undefined}
     */
    get E2E() {
        return this.m[8];
    }

    /**
     * Set Exterior to Exterior intersection
     * @param geom
     */
    set E2E(geom) {
        this.m[8] = geom;
    }

    /**
     * Return de9im matrix as string where<br/>
     * - intersection is 'T'<br/>
     * - not intersected is 'F'<br/>
     * - not relevant is '*'<br/>
     * For example, string 'FF**FF****' means 'DISJOINT'
     * @returns {string}
     */
    toString() {
        return this.m.map( e => {
            if (e instanceof Array && e.length > 0) {
                return 'T'
            }
            else if (e instanceof Array && e.length === 0) {
                return 'F'
            }
            else {
                return '*'
            }
        }).join("")
    }

    equal() {
        return EQUAL.test(this.toString());
    }

    intersect() {
        return INTERSECT.test(this.toString());
    }

    touch() {
        return TOUCH.test(this.toString());
    }

    inside() {
        return INSIDE.test(this.toString());
    }

    covered() {
        return COVERED.test(this.toString());
    }
}

export default DE9IM;