How to update vertices geometry after rotate or move object

Question

I can use position & rotation values to transform a mesh.

Ok, I see how the changes looks right but I\'d want a way to transform the geometry vertices x,y,z, fre

Answer 1

While building a ground mesh using a PlaneGeometry, adding hills using a heightmap and then getting some random vertices from the mesh geometry and adding trees after rotating the ground using

ground_mesh.rotation.set(-Math.PI / 2, 0, 0);

the mesh.geometry vertices aren't rotated along with the mesh and my trees are placed in pre-mesh-rotation positions. I found a quick and easy solution by instead rotating the mesh using

ground_mesh.geometry.rotateX(-Math.PI / 2)

and everything, including my gravity collision detection, and the random vertices all provide the expected results.

The documentation mentions that rotateX shouldn't be used during the rendering loop.