そのため、three.js エディターを使用して .obj ファイルを JSON に変換しようとしました。ジオメトリのエクスポートをクリックしても、何も起こりません...
http://mrdoob.github.io/three.js/editor/
ただし、シーンをエクスポートすると、次のように大量の数値が得られます。
"2,1615,1614,1671,1672,1615,3683,3563,3682,3684,3567,57,1615,1672,1673,1616,1615,1672,1673,1616,3685,3567,3684,3686,3570" ,57,1616,1673,1674,1617,1616,1673,1674,1617,3687,3570,3686,3688,3573,57,1617,1674,1675,1618,1617,1674,1675,1618,3689,3573 ,3688,3690,3575,57,1618,1675,1676,1619,1618,1675,1676,1619,3691,3575,3690,3692,3577,57,1619,1676,1677,1620,1619,1676,1677 ,1620,3693,3577,3692,3694,3579,57,1620,1677,1678,1621,1620,1677,1678,1621,3695,3579,3694,3696,3581,57,1624,1679,1680,1625 ,1624,1679,1680,1625,3697,3587,3698,3698,3587,57,1625,1680,1681,1626,1625,1680,1681,1626,3699,3589,3700,3701,3590,57,1626 ,1681,1682,1627,1626,1681,1682,1627,3702,3590,3701,3703,3592,57,1627,1682,1683,1628,1627,1682,1683,1628,3704,3592,3703,3705 ,3594,57,1628,1683,1684,1629,1628,1683,1684,1629,3706,3594,3705,3707,3596,57,1629,1684,1685,1630,1629,1684,1685,1630,3708 ,3596,3707,3709,3598,57,1630,1685,1686,1631,1630,1685,1686,1631,3710,3598,3709,3711,3600,57,1631,1686,1687,1632,1631,1686,1687, 1632,3712,3600,3711,3713,3602,57,1632,1687,1688,1633,1632,1687,1688,1633,3714,3602,3713,3715,3604,57,1633,1688,1689,1634, 1633,1688,1689,1634,3716,3604,3715,3717,3606,57,1634,1689,1690,1635,1634,1689,1690,1635,3718,3608,3719,3720,3609,57,1635, 、 3613,57,1637,1692,1693,1638,1637,1692,1693,1638,3725,3613,3724,3726,3615,57,1638,1693,1694,1639,1638,1693,1694,1639,3727, 3615,3726,3728,3617,57,1639,1694,1695,1640,1639,1694,1695,1640,3729,3617,3728,3730,3619,57,1640,1695,169"3713,3602,57,1632,1687,1688,1633,1632,1687,1688,1633,3714,3602,3713,3715,3604,57,1633,1688,1689,1634,1633,1688,1689,1634, 3716,3604,3715,3717,3606,57,1634,1689,1690,1635,1634,1689,1690,1635,3718,3608,3719,3720,3609,57,1635,1690,1691,1636,1635, 1690,1691,1636,3721,3609,3720,3722,3611,57,1636,1691,1692,1637,1636,1691,1692,1637,3723,3611,3722,3724,3613,57,1637,1692, 1693,1638,1637,1692,1693,1638,3725,3613,3724,3726,3615,57,1638,1693,1694,1639,1638,1693,1694,1639,3727,3615,3726,3728,3617, 57,1639,1694,1695,1640,1639,1694,1695,1640,3729,3617,3728,3730,3619,57,1640,1695,169"3713,3602,57,1632,1687,1688,1633,1632,1687,1688,1633,3714,3602,3713,3715,3604,57,1633,1688,1689,1634,1633,1688,1689,1634, 3716,3604,3715,3717,3606,57,1634,1689,1690,1635,1634,1689,1690,1635,3718,3608,3719,3720,3609,57,1635,1690,1691,1636,1635, 1690,1691,1636,3721,3609,3720,3722,3611,57,1636,1691,1692,1637,1636,1691,1692,1637,3723,3611,3722,3724,3613,57,1637,1692, 1693,1638,1637,1692,1693,1638,3725,3613,3724,3726,3615,57,1638,1693,1694,1639,1638,1693,1694,1639,3727,3615,3726,3728,3617, 57,1639,1694,1695,1640,1639,1694,1695,1640,3729,3617,3728,3730,3619,57,1640,1695,169"、 3726,3615,57,1638,1693,1694,1639,1638,1693,1694,1639,3727,3615,3726,3728,3617,57,1639,1694,1695,1640,1639,1694,1695,1640, 3729,3617,3728,3730,3619,57,1640,1695,169"、 3726,3615,57,1638,1693,1694,1639,1638,1693,1694,1639,3727,3615,3726,3728,3617,57,1639,1694,1695,1640,1639,1694,1695,1640, 3729,3617,3728,3730,3619,57,1640,1695,169"
これは、探している JSON ファイルの内容ですか? もしそうなら、nameofmodel.json として保存しますか?