How to clear out rotation of loaded model - three.js

Question

I have a model, which is displayed in Three.js correctly. Top at the top, bottom at the bottom. However, model has a preset rotation of -1.57 on X axis. It means If I add any new object to the scene, axis of object will be not the same as the model axis. How can clear out or reset this preset rotation so the axis of model and axis of world will match and top will be still at the top? I hope I explained myself clear. Thank you.

Answer 1

How about to rotate yours model once by 1.57, "burn" this orientation back to the vertices of the model then saving it to new file.
// reset mesh rotation
mesh.rotation.y = 1.57;
// make current oreintation, the base of the model
applyMeshTransformation(mesh);
// export the model to new blob file (can saved from this to new file)
exportObject(mesh)
function applyMeshTransformation(mesh) {
// apply local matrix on geometry
mesh.updateMatrixWorld();
mesh.geometry.applyMatrix(mesh.matrixWorld);
// reset local matrix
mesh.position.set(0,0,0);
mesh.rotation.set(0,0,0);
mesh.scale.set(1,1,1);
mesh.updateMatrixWorld();
};
function exportObject(mesh) {
var objExporter = new THREE.ObjectExporter();
var output = JSON.stringify( objExporter.parse( mesh ), null, '\t' );
output = output.replace( /[\n\t]+([\d\.e\-\[\]]+)/g, '$1' );
var blob = new Blob( [ output ], { type: 'text/plain' } );
var objectURL = window.URL.createObjectURL( blob );
window.open( objectURL, '_blank' );
};