// Define the id of your board in BOARDID
var board = JXG.JSXGraph.initBoard(BOARDID, {
boundingbox: [-8, 8, 8, -8],
keepaspectratio: false,
axis: false
});
var view = board.create('view3d',
[
[-6, -3],
[8, 8], // 2D box of view
[
[-5, 5],
[-5, 5],
[-5, 5]
]
], // 3D bounding cube
{});
// Point A (free point)
var p = view.create('point3d', [1, 1, 2], {size: 5, name:'A'});
view.create('line3d', [p, [1, 0, 0], [0, () => -p.X() - 5]], {dash: 1});
view.create('line3d', [p, [0, 1, 0], [0, () => -p.Y() - 5]], {dash: 1});
view.create('line3d', [p, [0, 0, 1], [0, () => -p.Z() - 5]], {dash: 1});