Is it possible to do rotations taking axis of the world and not of the object?
I need to do some rotations of an object, but after the first rotation, I can\'t do ot
Updated answer from @Neil (tested on r98
)
function rotateAroundWorldAxis(obj, axis, radians) {
let rotWorldMatrix = new THREE.Matrix4();
rotWorldMatrix.makeRotationAxis(axis.normalize(), radians);
rotWorldMatrix.multiply(obj.matrix);
obj.matrix = rotWorldMatrix;
obj.setRotationFromMatrix(obj.matrix);
}
THREE - r107
// select the Z world axis
this.myAxis = new Vector3(0, 0, 1);
// rotate the mesh 45 on this axis
this.mesh.rotateOnWorldAxis(this.myAxis, Math.degToRad(45));
animate() {
// rotate our object on its Y axis,
// but notice the cube has been transformed on world axis, so it will be tilted 45deg.
this.mesh.rotation.y += 0.008;
}
Somewhere around r59 this gets a lot easier (rotate around x):
bb.GraphicsEngine.prototype.calcRotation = function ( obj, rotationX)
{
var euler = new THREE.Euler( rotationX, 0, 0, 'XYZ' );
obj.position.applyEuler(euler);
}
Here's a small variation. Tested with r56.
THREE.Object3D._matrixAux = new THREE.Matrix4(); // global auxiliar variable
// Warnings: 1) axis is assumed to be normalized.
// 2) matrix must be updated. If not, call object.updateMatrix() first
// 3) this assumes we are not using quaternions
THREE.Object3D.prototype.rotateAroundWorldAxis = function(axis, radians) {
THREE.Object3D._matrixAux.makeRotationAxis(axis, radians);
this.matrix.multiplyMatrices(THREE.Object3D._matrixAux,this.matrix); // r56
THREE.Object3D._matrixAux.extractRotation(this.matrix);
this.rotation.setEulerFromRotationMatrix(THREE.Object3D._matrixAux, this.eulerOrder );
this.position.getPositionFromMatrix( this.matrix );
}
THREE.Object3D.prototype.rotateAroundWorldAxisX = function(radians) {
this._vector.set(1,0,0);
this.rotateAroundWorldAxis(this._vector,radians);
}
THREE.Object3D.prototype.rotateAroundWorldAxisY = function(radians) {
this._vector.set(0,1,0);
this.rotateAroundWorldAxis(this._vector,radians);
}
THREE.Object3D.prototype. rotateAroundWorldAxisZ = function(degrees){
this._vector.set(0,0,1);
this.rotateAroundWorldAxis(this._vector,degrees);
}
The three last lines are just to resync the params (position,rotation)
from the matrix... I wonder if there is a more efficient way to do that...
@acarlon Your answer might just have ended a week of frustration. I've refined your function a bit. Here are my variations. I hope this saves someone else the 20+ hours I spent trying to figure this out.
function calcRotationAroundAxis( obj3D, axis, angle ){
var euler;
if ( axis === "x" ){
euler = new THREE.Euler( angle, 0, 0, 'XYZ' );
}
if ( axis === "y" ){
euler = new THREE.Euler( 0, angle, 0, 'XYZ' );
}
if ( axis === "z" ){
euler = new THREE.Euler( 0, 0, angle, 'XYZ' );
}
obj3D.position.applyEuler( euler );
}
function calcRotationIn3D( obj3D, angles, order = 'XYZ' ){
var euler;
euler = new THREE.Euler( angles.x, angles.y, angles.z, order );
obj3D.position.applyEuler( euler );
}
This works beautifully in r91. Hope it helps.