@jscad/modeling/src/maths/vec3/lerp.test.js

Constructive Solid Geometry (CSG) Library for JSCAD

const test = require('ava')
const { lerp, fromValues } = require('./index')

const { compareVectors } = require('../../../test/helpers/index')

test('vec3: lerp() called with three parameters should update a vec3 with correct values', (t) => {
  const obs1 = fromValues(0, 0, 0)
  const ret1 = lerp(obs1, [0, 0, 0], [0, 0, 0], 0)
  t.true(compareVectors(obs1, [0, 0, 0]))
  t.true(compareVectors(ret1, [0, 0, 0]))

  const obs2 = fromValues(0, 0, 0)
  const ret2 = lerp(obs2, [1, 2, 3], [5, 6, 7], 0.00)
  t.true(compareVectors(obs2, [1, 2, 3]))
  t.true(compareVectors(ret2, [1, 2, 3]))

  const obs3 = fromValues(0, 0, 0)
  const ret3 = lerp(obs3, [1, 2, 3], [5, 6, 7], 0.75)
  t.true(compareVectors(obs3, [4, 5, 6]))
  t.true(compareVectors(ret3, [4, 5, 6]))

  const obs4 = fromValues(0, 0, 0)
  const ret4 = lerp(obs4, [1, 2, 3], [5, 6, 7], 1.00)
  t.true(compareVectors(obs4, [5, 6, 7]))
  t.true(compareVectors(ret4, [5, 6, 7]))
})