Irrlicht Engine

Hallo
Is it p

Unfortunately no, because internally ISceneNode saves position, rotation and scale instead of a matrix and just calculates the matrix from those when needed. It is possible to use an IDummyTransformationSceneNode as parent which accepts matrices directly. That has a bit overhead as the matrix is then multiplied by the scenenode matrix, but if you don't have too many nodes it won't matter much.

ok

You can use the quaternion::toEuler function if it's only about rotations and wanting to work with quaternions in your code.