freesewing/tests/utils.test.js

let expect = require("chai").expect;
let freesewing = require("./dist/index.js");
let utils = freesewing.utils;

it("Should return the correct macro name", () => {
  expect(utils.macroName("test")).to.equal("_macro_test");
});

it("Should find the intersection of two endless line segments", () => {
  let a = new freesewing.Point(10, 20);
  let b = new freesewing.Point(20, 24);
  let c = new freesewing.Point(90, 19);
  let d = new freesewing.Point(19, 70);
  let X = freesewing.utils.beamsIntersect(a, b, c, d);
  expect(X.x).to.equal(60.49);
  expect(X.y).to.equal(40.2);
});

it("Should detect parallel lines", () => {
  let a = new freesewing.Point(10, 20);
  let b = new freesewing.Point(20, 20);
  let c = new freesewing.Point(90, 40);
  let d = new freesewing.Point(19, 40);
  expect(freesewing.utils.beamsIntersect(a, b, c, d)).to.equal(false);
  expect(freesewing.utils.linesIntersect(a, b, c, d)).to.equal(false);
});

it("Should detect vertical lines", () => {
  let a = new freesewing.Point(10, 20);
  let b = new freesewing.Point(10, 90);
  let c = new freesewing.Point(90, 40);
  let d = new freesewing.Point(19, 40);
  let X = freesewing.utils.beamsIntersect(a, b, c, d);
  expect(X.x).to.equal(10);
  expect(X.y).to.equal(40);
  X = freesewing.utils.beamsIntersect(c, d, a, b);
  expect(X.x).to.equal(10);
});

it("Should swap direction prior to finding beam intersection", () => {
  let a = new freesewing.Point(10, 20);
  let b = new freesewing.Point(00, 90);
  let c = new freesewing.Point(90, 40);
  let d = new freesewing.Point(19, 40);
  let X = freesewing.utils.beamsIntersect(a, b, c, d);
  expect(X.x).to.equal(7.14);
  expect(X.y).to.equal(40);
});

it("Should return false when two lines don't intersect", () => {
  let a = new freesewing.Point(10, 20);
  let b = new freesewing.Point(20, 24);
  let c = new freesewing.Point(90, 19);
  let d = new freesewing.Point(19, 70);
  expect(freesewing.utils.linesIntersect(a, b, c, d)).to.equal(false);
});

it("Should find the intersection of two line segments", () => {
  let a = new freesewing.Point(10, 10);
  let b = new freesewing.Point(90, 74);
  let c = new freesewing.Point(90, 19);
  let d = new freesewing.Point(11, 70);
  let X = freesewing.utils.linesIntersect(a, b, c, d);
  expect(X.x).to.equal(51.95);
  expect(X.y).to.equal(43.56);
});

it("Should find the intersection of two line segments - round() edge case", () => {
  let a = new freesewing.Point(45, 60);
  let b = new freesewing.Point(10, 30);
  let c = new freesewing.Point(55, 40);
  let d = new freesewing.Point(0, 55);
  let X = freesewing.utils.linesIntersect(a, b, c, d);
  expect(X.x).to.equal(29.71);
  expect(X.y).to.equal(46.9);
});

it("Should find the intersection of an endles line and a give X-value", () => {
  let a = new freesewing.Point(10, 10);
  let b = new freesewing.Point(90, 74);
  let X = freesewing.utils.beamIntersectsX(a, b, 69);
  expect(X.x).to.equal(69);
  expect(X.y).to.equal(57.2);
});

it("Should find the intersection of an endles line and a give Y-value", () => {
  let a = new freesewing.Point(10, 10);
  let b = new freesewing.Point(90, 74);
  let X = freesewing.utils.beamIntersectsY(a, b, 69);
  expect(X.x).to.equal(83.75);
  expect(X.y).to.equal(69);
});

it("Should detect vertical lines never pass a give X-value", () => {
  let a = new freesewing.Point(10, 10);
  let b = new freesewing.Point(10, 90);
  expect(freesewing.utils.beamIntersectsX(a, b, 69)).to.equal(false);
});

it("Should detect horizontal lines never pass a give Y-value", () => {
  let a = new freesewing.Point(10, 10);
  let b = new freesewing.Point(90, 10);
  expect(freesewing.utils.beamIntersectsY(a, b, 69)).to.equal(false);
});

it("Should find no intersections between a curve and a line", () => {
  let A = new freesewing.Point(10, 10);
  let Acp = new freesewing.Point(310, 40);
  let B = new freesewing.Point(110, 70);
  let Bcp = new freesewing.Point(-210, 40);
  let E = new freesewing.Point(-20, -20);
  let D = new freesewing.Point(30, -85);

  let hit = freesewing.utils.lineIntersectsCurve(E, D, A, Acp, Bcp, B);
  expect(hit).to.equal(false);
});

it("Should find 1 intersection between a curve and a line", () => {
  let A = new freesewing.Point(10, 10);
  let Acp = new freesewing.Point(310, 40);
  let B = new freesewing.Point(110, 70);
  let Bcp = new freesewing.Point(-210, 40);
  let E = new freesewing.Point(20, 20);
  let D = new freesewing.Point(30, -85);

  let hit = freesewing.utils.lineIntersectsCurve(E, D, A, Acp, Bcp, B);
  expect(hit.x).to.equal(20.85);
  expect(hit.y).to.equal(11.11);
});

it("Should find 3 intersections between a curve and a line", () => {
  let A = new freesewing.Point(10, 10);
  let Acp = new freesewing.Point(310, 40);
  let B = new freesewing.Point(110, 70);
  let Bcp = new freesewing.Point(-210, 40);
  let E = new freesewing.Point(20, -5);
  let D = new freesewing.Point(100, 85);

  let hits = freesewing.utils.lineIntersectsCurve(E, D, A, Acp, Bcp, B);
  expect(hits.length).to.equal(3);
});

it("Should find 9 intersections between two curves", () => {
  let A = new freesewing.Point(10, 10);
  let Acp = new freesewing.Point(310, 40);
  let B = new freesewing.Point(110, 70);
  let Bcp = new freesewing.Point(-210, 40);
  let C = new freesewing.Point(20, -5);
  let Ccp = new freesewing.Point(60, 300);
  let D = new freesewing.Point(100, 85);
  let Dcp = new freesewing.Point(70, -220);

  let hits = freesewing.utils.curvesIntersect(A, Acp, Bcp, B, C, Ccp, Dcp, D);
  expect(hits.length).to.equal(9);
});

it("Should find 1 intersection between two curves", () => {
  let A = new freesewing.Point(10, 10);
  let Acp = new freesewing.Point(310, 40);
  let B = new freesewing.Point(110, 70);
  let Bcp = new freesewing.Point(-210, 40);
  let C = new freesewing.Point(20, -5);
  let Ccp = new freesewing.Point(-60, 300);
  let D = new freesewing.Point(-200, 85);
  let Dcp = new freesewing.Point(-270, -220);

  let hit = freesewing.utils.curvesIntersect(A, Acp, Bcp, B, C, Ccp, Dcp, D);
  expect(hit.x).to.equal(15.58);
  expect(hit.y).to.equal(10.56);
});

it("Should find no intersection between two curves", () => {
  let A = new freesewing.Point(10, 10);
  let Acp = new freesewing.Point(310, 40);
  let B = new freesewing.Point(110, 70);
  let Bcp = new freesewing.Point(-210, 40);
  let C = new freesewing.Point(20, -5);
  let Ccp = new freesewing.Point(-60, -300);
  let D = new freesewing.Point(-200, 85);
  let Dcp = new freesewing.Point(-270, -220);

  let hit = freesewing.utils.curvesIntersect(A, Acp, Bcp, B, C, Ccp, Dcp, D);
  expect(hit).to.equal(false);
});

it("Should correctly format units", () => {
  expect(freesewing.utils.units(123.456)).to.equal("12.35cm");
  expect(freesewing.utils.units(123.456, "imperial")).to.equal('4.86"');
});

it("Should find a start or end point on beam", () => {
  let A = new freesewing.Point(12, 34);
  let B = new freesewing.Point(56, 78);
  let checkA = new freesewing.Point(12, 34);
  let checkB = new freesewing.Point(56, 78);
  expect(freesewing.utils.pointOnBeam(A, B, checkA)).to.equal(true);
  expect(freesewing.utils.pointOnBeam(A, B, checkB)).to.equal(true);
});

it("Should find whether a point lies on a line segment", () => {
  let A = new freesewing.Point(12, 34);
  let B = new freesewing.Point(56, 78);
  let check1 = A.shiftTowards(B, 10);
  let check2 = A.shiftTowards(B, 210);
  expect(freesewing.utils.pointOnLine(A, B, check1)).to.equal(true);
  expect(freesewing.utils.pointOnLine(A, B, check2)).to.equal(false);
});

it("Should find a start or end point on curve", () => {
  let A = new freesewing.Point(12, 34);
  let Acp = new freesewing.Point(123, 4);
  let B = new freesewing.Point(56, 78);
  let Bcp = new freesewing.Point(5, 678);
  let checkA = new freesewing.Point(12, 34);
  let checkB = new freesewing.Point(56, 78);
  expect(freesewing.utils.pointOnCurve(A, Acp, Bcp, B, checkA)).to.equal(true);
  expect(freesewing.utils.pointOnCurve(A, Acp, Bcp, B, checkB)).to.equal(true);
});

it("Should find the intersections of a beam and circle", () => {
  let A = new freesewing.Point(45, 45).attr("data-circle", 35);
  let B = new freesewing.Point(5, 50);
  let C = new freesewing.Point(25, 30);
  let intersections = freesewing.utils.beamIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C,
    "y"
  );
  expect(intersections.length).to.equal(2);
  expect(intersections[0].x).to.equal(45);
  expect(intersections[0].y).to.equal(10);
  expect(intersections[1].x).to.equal(10);
  expect(intersections[1].y).to.equal(45);
});

it("Should not find the intersections of this beam and circle", () => {
  let A = new freesewing.Point(75, 75).attr("data-circle", 35);
  let B = new freesewing.Point(5, 5);
  let C = new freesewing.Point(10, 5);
  let intersections = freesewing.utils.beamIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C
  );
  expect(intersections).to.equal(false);
});

it("Should find one intersections between this beam and circle", () => {
  let A = new freesewing.Point(5, 5).attr("data-circle", 5);
  let B = new freesewing.Point(0, 0);
  let C = new freesewing.Point(-10, 0);
  let intersections = freesewing.utils.beamIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C
  );
  expect(intersections.length).to.equal(1);
  expect(intersections[0].x).to.equal(5);
  expect(intersections[0].y).to.equal(0);
});

it("Should find one intersections between this tangent and circle", () => {
  let A = new freesewing.Point(5, 5).attr("data-circle", 5);
  let B = new freesewing.Point(0, 0);
  let C = new freesewing.Point(10, 0);
  let intersections = freesewing.utils.lineIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C
  );
  expect(intersections.length).to.equal(1);
  expect(intersections[0].x).to.equal(5);
  expect(intersections[0].y).to.equal(0);
});

it("Should find one intersection between this line and circle", () => {
  let A = new freesewing.Point(5, 5).attr("data-circle", 5);
  let B = new freesewing.Point(5, 5);
  let C = new freesewing.Point(26, 25);
  let intersections = freesewing.utils.lineIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C
  );
  expect(intersections.length).to.equal(1);
  expect(intersections[0].x).to.equal(8.62);
  expect(intersections[0].y).to.equal(8.45);
});

it("Should not find an intersections between this line and circle", () => {
  let A = new freesewing.Point(5, 5).attr("data-circle", 5);
  let B = new freesewing.Point(0, 0);
  let C = new freesewing.Point(-10, 0);
  let intersections = freesewing.utils.lineIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C
  );
  expect(intersections).to.equal(false);
});

it("Should find two intersections between this line and circle", () => {
  let A = new freesewing.Point(6, 7).attr("data-circle", 5);
  let B = new freesewing.Point(0, 10);
  let C = new freesewing.Point(10, 0);
  let intersections1 = freesewing.utils.lineIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C,
    "foo"
  );
  let intersections2 = freesewing.utils.lineIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C,
    "x"
  );
  let intersections3 = freesewing.utils.lineIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C,
    "y"
  );
  expect(intersections1.length).to.equal(2);
  expect(intersections2.length).to.equal(2);
  expect(intersections3.length).to.equal(2);
  expect(intersections1[0].sitsOn(intersections2[1])).to.equal(true);
  expect(intersections1[1].sitsOn(intersections2[0])).to.equal(true);
  expect(intersections1[0].sitsOn(intersections3[0])).to.equal(true);
  expect(intersections1[1].sitsOn(intersections3[1])).to.equal(true);
  expect(intersections1[0].x).to.equal(7.7);
  expect(intersections1[0].y).to.equal(2.3);
  expect(intersections1[1].x).to.equal(1.3);
  expect(intersections1[1].y).to.equal(8.7);
});

it("Should find the intersections of a line and circle", () => {
  let A = new freesewing.Point(45, 45).attr("data-circle", 35);
  let B = new freesewing.Point(5, 50);
  let C = new freesewing.Point(25, 30);
  let intersections = freesewing.utils.lineIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C
  );
  expect(intersections.length).to.equal(1);
  expect(intersections[0].x).to.equal(10);
  expect(intersections[0].y).to.equal(45);
});

it("Should not find intersections of this line and circle", () => {
  let A = new freesewing.Point(75, 75).attr("data-circle", 35);
  let B = new freesewing.Point(5, 5);
  let C = new freesewing.Point(10, 5);
  let intersections = freesewing.utils.lineIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C
  );
  expect(intersections).to.equal(false);
});

it("Should not find intersections of this line and circle", () => {
  let A = new freesewing.Point(45, 45).attr("data-circle", 35);
  let B = new freesewing.Point(40, 40);
  let C = new freesewing.Point(52, 50);
  let intersections = freesewing.utils.lineIntersectsCircle(
    A,
    A.attributes.get("data-circle"),
    B,
    C
  );
  expect(intersections).to.equal(false);
});

it("Should find intersections between circles", () => {
  A = new freesewing.Point(10, 10).attr("data-circle", 15);
  B = new freesewing.Point(30, 30).attr("data-circle", 35);

  let intersections1 = freesewing.utils.circlesIntersect(
    A,
    A.attributes.get("data-circle"),
    B,
    B.attributes.get("data-circle")
  );
  let intersections2 = freesewing.utils.circlesIntersect(
    A,
    A.attributes.get("data-circle"),
    B,
    B.attributes.get("data-circle"),
    "y"
  );
  expect(intersections1.length).to.equal(2);
  expect(intersections2.length).to.equal(2);
  expect(intersections1[0].x).to.equal(-2.81);
  expect(intersections1[0].y).to.equal(17.8);
  expect(intersections1[1].x).to.equal(17.8);
  expect(intersections1[1].y).to.equal(-2.81);
  expect(intersections2[0].x).to.equal(17.8);
  expect(intersections2[0].y).to.equal(-2.81);
  expect(intersections2[1].x).to.equal(-2.81);
  expect(intersections2[1].y).to.equal(17.8);
});

it("Should not find intersections between non-overlapping circles", () => {
  A = new freesewing.Point(10, 10).attr("data-circle", 15);
  B = new freesewing.Point(90, 90).attr("data-circle", 35);

  let intersections = freesewing.utils.circlesIntersect(
    A,
    A.attributes.get("data-circle"),
    B,
    B.attributes.get("data-circle")
  );
  expect(intersections).to.equal(false);
});

it("Should not find intersections between contained circles", () => {
  A = new freesewing.Point(10, 10).attr("data-circle", 15);
  B = new freesewing.Point(10, 10).attr("data-circle", 35);

  let intersections = freesewing.utils.circlesIntersect(
    A,
    A.attributes.get("data-circle"),
    B,
    B.attributes.get("data-circle")
  );
  expect(intersections).to.equal(false);
});

it("Should not find intersections between identical circles", () => {
  A = new freesewing.Point(10, 10).attr("data-circle", 35);
  B = new freesewing.Point(10, 10).attr("data-circle", 35);

  let intersections = freesewing.utils.circlesIntersect(
    A,
    A.attributes.get("data-circle"),
    B,
    B.attributes.get("data-circle")
  );
  expect(intersections).to.equal(false);
});

it("Should return scale for a given amount of stretch", () => {
  expect(freesewing.utils.stretchToScale(0)).to.equal(1);
  expect(freesewing.utils.stretchToScale(0.15)).to.equal(0.9);
});