three.js/test/unit/src/math/Triangle.tests.js

/* global QUnit */

import { BufferAttribute } from '../../../../src/core/BufferAttribute';
import { Triangle } from '../../../../src/math/Triangle';
import { Box3 } from '../../../../src/math/Box3';
import { Plane } from '../../../../src/math/Plane';
import { Vector3 } from '../../../../src/math/Vector3';
import {
	zero3,
	one3,
	two3
} from './Constants.tests';

export default QUnit.module( 'Maths', () => {

	QUnit.module( 'Triangle', () => {

		// INSTANCING
		QUnit.test( "Instancing", ( assert ) => {

			var a = new Triangle();
			assert.ok( a.a.equals( zero3 ), "Passed!" );
			assert.ok( a.b.equals( zero3 ), "Passed!" );
			assert.ok( a.c.equals( zero3 ), "Passed!" );

			var a = new Triangle( one3.clone().negate(), one3.clone(), two3.clone() );
			assert.ok( a.a.equals( one3.clone().negate() ), "Passed!" );
			assert.ok( a.b.equals( one3 ), "Passed!" );
			assert.ok( a.c.equals( two3 ), "Passed!" );

		} );

		// STATIC STUFF
		QUnit.todo( "getNormal", ( assert ) => {

			assert.ok( false, "everything's gonna be alright" );

		} );

		QUnit.todo( "getBarycoord", ( assert ) => {

			assert.ok( false, "everything's gonna be alright" );

		} );

		QUnit.todo( "containsPoint", ( assert ) => {

			assert.ok( false, "everything's gonna be alright" );

		} );

		// PUBLIC STUFF
		QUnit.test( "set", ( assert ) => {

			var a = new Triangle();

			a.set( one3.clone().negate(), one3, two3 );
			assert.ok( a.a.equals( one3.clone().negate() ), "Passed!" );
			assert.ok( a.b.equals( one3 ), "Passed!" );
			assert.ok( a.c.equals( two3 ), "Passed!" );

		} );

		QUnit.test( "setFromPointsAndIndices", ( assert ) => {

			var a = new Triangle();

			var points = [ one3, one3.clone().negate(), two3 ];
			a.setFromPointsAndIndices( points, 1, 0, 2 );
			assert.ok( a.a.equals( one3.clone().negate() ), "Passed!" );
			assert.ok( a.b.equals( one3 ), "Passed!" );
			assert.ok( a.c.equals( two3 ), "Passed!" );

		} );

		QUnit.test( "setFromAttributeAndIndices", ( assert ) => {

			var a = new Triangle();
			var attribute = new BufferAttribute( new Float32Array( [ 1, 1, 1, - 1, - 1, - 1, 2, 2, 2 ] ), 3 );

			a.setFromAttributeAndIndices( attribute, 1, 0, 2 );
			assert.ok( a.a.equals( one3.clone().negate() ), "Passed!" );
			assert.ok( a.b.equals( one3 ), "Passed!" );
			assert.ok( a.c.equals( two3 ), "Passed!" );

		} );

		QUnit.todo( "clone", ( assert ) => {

			assert.ok( false, "everything's gonna be alright" );

		} );

		QUnit.test( "copy", ( assert ) => {

			var a = new Triangle( one3.clone().negate(), one3.clone(), two3.clone() );
			var b = new Triangle().copy( a );
			assert.ok( b.a.equals( one3.clone().negate() ), "Passed!" );
			assert.ok( b.b.equals( one3 ), "Passed!" );
			assert.ok( b.c.equals( two3 ), "Passed!" );

			// ensure that it is a true copy
			a.a = one3;
			a.b = zero3;
			a.c = zero3;
			assert.ok( b.a.equals( one3.clone().negate() ), "Passed!" );
			assert.ok( b.b.equals( one3 ), "Passed!" );
			assert.ok( b.c.equals( two3 ), "Passed!" );

		} );

		QUnit.test( "getArea", ( assert ) => {

			var a = new Triangle();

			assert.ok( a.getArea() == 0, "Passed!" );

			var a = new Triangle( new Vector3( 0, 0, 0 ), new Vector3( 1, 0, 0 ), new Vector3( 0, 1, 0 ) );
			assert.ok( a.getArea() == 0.5, "Passed!" );

			var a = new Triangle( new Vector3( 2, 0, 0 ), new Vector3( 0, 0, 0 ), new Vector3( 0, 0, 2 ) );
			assert.ok( a.getArea() == 2, "Passed!" );

			// colinear triangle.
			var a = new Triangle( new Vector3( 2, 0, 0 ), new Vector3( 0, 0, 0 ), new Vector3( 3, 0, 0 ) );
			assert.ok( a.getArea() == 0, "Passed!" );

		} );

		QUnit.test( "getMidpoint", ( assert ) => {

			var a = new Triangle();
			var midpoint = new Vector3();

			assert.ok( a.getMidpoint( midpoint ).equals( new Vector3( 0, 0, 0 ) ), "Passed!" );

			var a = new Triangle( new Vector3( 0, 0, 0 ), new Vector3( 1, 0, 0 ), new Vector3( 0, 1, 0 ) );
			assert.ok( a.getMidpoint( midpoint ).equals( new Vector3( 1 / 3, 1 / 3, 0 ) ), "Passed!" );

			var a = new Triangle( new Vector3( 2, 0, 0 ), new Vector3( 0, 0, 0 ), new Vector3( 0, 0, 2 ) );
			assert.ok( a.getMidpoint( midpoint ).equals( new Vector3( 2 / 3, 0, 2 / 3 ) ), "Passed!" );

		} );

		QUnit.test( "getNormal", ( assert ) => {

			var a = new Triangle();
			var normal = new Vector3();

			assert.ok( a.getNormal( normal ).equals( new Vector3( 0, 0, 0 ) ), "Passed!" );

			var a = new Triangle( new Vector3( 0, 0, 0 ), new Vector3( 1, 0, 0 ), new Vector3( 0, 1, 0 ) );
			assert.ok( a.getNormal( normal ).equals( new Vector3( 0, 0, 1 ) ), "Passed!" );

			var a = new Triangle( new Vector3( 2, 0, 0 ), new Vector3( 0, 0, 0 ), new Vector3( 0, 0, 2 ) );
			assert.ok( a.getNormal( normal ).equals( new Vector3( 0, 1, 0 ) ), "Passed!" );

		} );

		QUnit.test( "getPlane", ( assert ) => {

			var a = new Triangle();
			var plane = new Plane();
			var normal = new Vector3();

			a.getPlane( plane );
			assert.notOk( isNaN( plane.distanceToPoint( a.a ) ), "Passed!" );
			assert.notOk( isNaN( plane.distanceToPoint( a.b ) ), "Passed!" );
			assert.notOk( isNaN( plane.distanceToPoint( a.c ) ), "Passed!" );
			assert.notPropEqual( plane.normal, {
				x: NaN,
				y: NaN,
				z: NaN
			}, "Passed!" );

			var a = new Triangle( new Vector3( 0, 0, 0 ), new Vector3( 1, 0, 0 ), new Vector3( 0, 1, 0 ) );
			a.getPlane( plane );
			a.getNormal( normal );
			assert.ok( plane.distanceToPoint( a.a ) == 0, "Passed!" );
			assert.ok( plane.distanceToPoint( a.b ) == 0, "Passed!" );
			assert.ok( plane.distanceToPoint( a.c ) == 0, "Passed!" );
			assert.ok( plane.normal.equals( normal ), "Passed!" );

			var a = new Triangle( new Vector3( 2, 0, 0 ), new Vector3( 0, 0, 0 ), new Vector3( 0, 0, 2 ) );
			a.getPlane( plane );
			a.getNormal( normal );
			assert.ok( plane.distanceToPoint( a.a ) == 0, "Passed!" );
			assert.ok( plane.distanceToPoint( a.b ) == 0, "Passed!" );
			assert.ok( plane.distanceToPoint( a.c ) == 0, "Passed!" );
			assert.ok( plane.normal.clone().normalize().equals( normal ), "Passed!" );

		} );

		QUnit.test( "getBarycoord", ( assert ) => {

			var a = new Triangle();

			var bad = new Vector3( - 2, - 1, - 1 );
			var barycoord = new Vector3();
			var midpoint = new Vector3();

			a.getBarycoord( a.a, barycoord );
			assert.ok( barycoord.equals( bad ), "Passed!" );
			a.getBarycoord( a.b, barycoord );
			assert.ok( barycoord.equals( bad ), "Passed!" );
			a.getBarycoord( a.c, barycoord );
			assert.ok( barycoord.equals( bad ), "Passed!" );

			var a = new Triangle( new Vector3( 0, 0, 0 ), new Vector3( 1, 0, 0 ), new Vector3( 0, 1, 0 ) );
			a.getMidpoint( midpoint );

			a.getBarycoord( a.a, barycoord );
			assert.ok( barycoord.equals( new Vector3( 1, 0, 0 ) ), "Passed!" );
			a.getBarycoord( a.b, barycoord );
			assert.ok( barycoord.equals( new Vector3( 0, 1, 0 ) ), "Passed!" );
			a.getBarycoord( a.c, barycoord );
			assert.ok( barycoord.equals( new Vector3( 0, 0, 1 ) ), "Passed!" );
			a.getBarycoord( midpoint, barycoord );
			assert.ok( barycoord.distanceTo( new Vector3( 1 / 3, 1 / 3, 1 / 3 ) ) < 0.0001, "Passed!" );

			var a = new Triangle( new Vector3( 2, 0, 0 ), new Vector3( 0, 0, 0 ), new Vector3( 0, 0, 2 ) );
			a.getMidpoint( midpoint );

			a.getBarycoord( a.a, barycoord );
			assert.ok( barycoord.equals( new Vector3( 1, 0, 0 ) ), "Passed!" );
			a.getBarycoord( a.b, barycoord );
			assert.ok( barycoord.equals( new Vector3( 0, 1, 0 ) ), "Passed!" );
			a.getBarycoord( a.c, barycoord );
			assert.ok( barycoord.equals( new Vector3( 0, 0, 1 ) ), "Passed!" );
			a.getBarycoord( midpoint, barycoord );
			assert.ok( barycoord.distanceTo( new Vector3( 1 / 3, 1 / 3, 1 / 3 ) ) < 0.0001, "Passed!" );

		} );

		QUnit.test( "containsPoint", ( assert ) => {

			var a = new Triangle();
			var midpoint = new Vector3();

			assert.ok( ! a.containsPoint( a.a ), "Passed!" );
			assert.ok( ! a.containsPoint( a.b ), "Passed!" );
			assert.ok( ! a.containsPoint( a.c ), "Passed!" );

			var a = new Triangle( new Vector3( 0, 0, 0 ), new Vector3( 1, 0, 0 ), new Vector3( 0, 1, 0 ) );
			a.getMidpoint( midpoint );
			assert.ok( a.containsPoint( a.a ), "Passed!" );
			assert.ok( a.containsPoint( a.b ), "Passed!" );
			assert.ok( a.containsPoint( a.c ), "Passed!" );
			assert.ok( a.containsPoint( midpoint ), "Passed!" );
			assert.ok( ! a.containsPoint( new Vector3( - 1, - 1, - 1 ) ), "Passed!" );

			var a = new Triangle( new Vector3( 2, 0, 0 ), new Vector3( 0, 0, 0 ), new Vector3( 0, 0, 2 ) );
			a.getMidpoint( midpoint );
			assert.ok( a.containsPoint( a.a ), "Passed!" );
			assert.ok( a.containsPoint( a.b ), "Passed!" );
			assert.ok( a.containsPoint( a.c ), "Passed!" );
			assert.ok( a.containsPoint( midpoint ), "Passed!" );
			assert.ok( ! a.containsPoint( new Vector3( - 1, - 1, - 1 ) ), "Passed!" );

		} );

		QUnit.test( "intersectsBox", ( assert ) => {

			var a = new Box3( one3.clone(), two3.clone() );
			var b = new Triangle( new Vector3( 1.5, 1.5, 2.5 ), new Vector3( 2.5, 1.5, 1.5 ), new Vector3( 1.5, 2.5, 1.5 ) );
			var c = new Triangle( new Vector3( 1.5, 1.5, 3.5 ), new Vector3( 3.5, 1.5, 1.5 ), new Vector3( 1.5, 1.5, 1.5 ) );
			var d = new Triangle( new Vector3( 1.5, 1.75, 3 ), new Vector3( 3, 1.75, 1.5 ), new Vector3( 1.5, 2.5, 1.5 ) );
			var e = new Triangle( new Vector3( 1.5, 1.8, 3 ), new Vector3( 3, 1.8, 1.5 ), new Vector3( 1.5, 2.5, 1.5 ) );
			var f = new Triangle( new Vector3( 1.5, 2.5, 3 ), new Vector3( 3, 2.5, 1.5 ), new Vector3( 1.5, 2.5, 1.5 ) );

			assert.ok( b.intersectsBox( a ), "Passed!" );
			assert.ok( c.intersectsBox( a ), "Passed!" );
			assert.ok( d.intersectsBox( a ), "Passed!" );
			assert.ok( ! e.intersectsBox( a ), "Passed!" );
			assert.ok( ! f.intersectsBox( a ), "Passed!" );

		} );

		QUnit.test( "closestPointToPoint", ( assert ) => {

			var a = new Triangle( new Vector3( - 1, 0, 0 ), new Vector3( 1, 0, 0 ), new Vector3( 0, 1, 0 ) );
			var point = new Vector3();

			// point lies inside the triangle
			a.closestPointToPoint( new Vector3( 0, 0.5, 0 ), point );
			assert.ok( point.equals( new Vector3( 0, 0.5, 0 ) ), "Passed!" );

			// point lies on a vertex
			a.closestPointToPoint( a.a, point );
			assert.ok( point.equals( a.a ), "Passed!" );

			a.closestPointToPoint( a.b, point );
			assert.ok( point.equals( a.b ), "Passed!" );

			a.closestPointToPoint( a.c, point );
			assert.ok( point.equals( a.c ), "Passed!" );

			// point lies on an edge
			a.closestPointToPoint( zero3.clone(), point );
			assert.ok( point.equals( zero3.clone() ), "Passed!" );

			// point lies outside the triangle
			a.closestPointToPoint( new Vector3( - 2, 0, 0 ), point );
			assert.ok( point.equals( new Vector3( - 1, 0, 0 ) ), "Passed!" );

			a.closestPointToPoint( new Vector3( 2, 0, 0 ), point );
			assert.ok( point.equals( new Vector3( 1, 0, 0 ) ), "Passed!" );

			a.closestPointToPoint( new Vector3( 0, 2, 0 ), point );
			assert.ok( point.equals( new Vector3( 0, 1, 0 ) ), "Passed!" );

			a.closestPointToPoint( new Vector3( 0, - 2, 0 ), point );
			assert.ok( point.equals( new Vector3( 0, 0, 0 ) ), "Passed!" );

		} );

		QUnit.test( "isFrontFacing", ( assert ) => {

			var a = new Triangle();
			var dir = new Vector3();
			assert.ok( ! a.isFrontFacing( dir ), "Passed!" );

			var a = new Triangle( new Vector3( 0, 0, 0 ), new Vector3( 1, 0, 0 ), new Vector3( 0, 1, 0 ) );
			var dir = new Vector3( 0, 0, - 1 );
			assert.ok( a.isFrontFacing( dir ), "Passed!" );

			var a = new Triangle( new Vector3( 0, 0, 0 ), new Vector3( 0, 1, 0 ), new Vector3( 1, 0, 0 ) );
			assert.ok( ! a.isFrontFacing( dir ), "Passed!" );

		} );

		QUnit.test( "equals", ( assert ) => {

			var a = new Triangle(
				new Vector3( 1, 0, 0 ),
				new Vector3( 0, 1, 0 ),
				new Vector3( 0, 0, 1 )
			);
			var b = new Triangle(
				new Vector3( 0, 0, 1 ),
				new Vector3( 0, 1, 0 ),
				new Vector3( 1, 0, 0 )
			);
			var c = new Triangle(
				new Vector3( - 1, 0, 0 ),
				new Vector3( 0, 1, 0 ),
				new Vector3( 0, 0, 1 )
			);

			assert.ok( a.equals( a ), "a equals a" );
			assert.notOk( a.equals( b ), "a does not equal b" );
			assert.notOk( a.equals( c ), "a does not equal c" );
			assert.notOk( b.equals( c ), "b does not equal c" );

			a.copy( b );
			assert.ok( a.equals( a ), "a equals b after copy()" );

		} );

	} );

} );