PlaneRotationGizmo - use rotation if quaternion is null

aWeirdo · July 28, 2019, 7:15pm

Hey guys,
Could we update PlaneRotationGizmo to use mesh.rotation if no quaternion is set?
Currently it forces a change to use mesh.rotationQuaternion.

github.com

BabylonJS/Babylon.js/blob/master/src/Gizmos/planeRotationGizmo.ts#L103


var planeNormalTowardsCamera = new Vector3();
var localPlaneNormalTowardsCamera = new Vector3();


var tmpSnapEvent = { snapDistance: 0 };
var currentSnapDragDistance = 0;
var tmpMatrix = new Matrix();
var tmpVector = new Vector3();
var amountToRotate = new Quaternion();
this.dragBehavior.onDragObservable.add((event) => {
    if (this.attachedMesh) {
        if (!this.attachedMesh.rotationQuaternion) {
            this.attachedMesh.rotationQuaternion = Quaternion.RotationYawPitchRoll(this.attachedMesh.rotation.y, this.attachedMesh.rotation.x, this.attachedMesh.rotation.z);
        }


        // Remove parent priort to rotating
        var attachedMeshParent = this.attachedMesh.parent;
        if (attachedMeshParent) {
            this.attachedMesh.setParent(null);
        }


        // Calc angle over full 360 degree (https://stackoverflow.com/questions/43493711/the-angle-between-two-3d-vectors-with-a-result-range-0-360)

To avoid issues with back-compat,
perhaps a (parent) RotationGizmo.useQuaternion property (default true) which switches to a different dragBehavior function for each child gizmo when changed ?

…and if you’re unaware of this (like me) and mindlessly use mesh.rotation in the rest of your code, it bugs out and you spend an hour wondering what’s going on … while thinking it looks perfectly fine and should work

Deltakosh · July 29, 2019, 4:34pm

Pinging @Cedric

Cedric · July 29, 2019, 5:05pm

I’m taking a look

aWeirdo · July 29, 2019, 8:56pm

cool, thanks!

Cedric · July 29, 2019, 9:15pm

Hi @aWeirdo
I’m not sure about the change. Correct me if I’m wrong: I guess your tried to read back mesh.rotation after doing some rotation using the gizmo and it was out of sync?
If it’s what happen, I’d prefer add a synchronization system to update mesh.rotation from the quaternion instead of changing the gizmo to work on euler.

Cedric · July 29, 2019, 10:11pm

I did a simple change to always use the Euler angle here when an option constructor Boolean is set to true:
‘’’

github.com

BabylonJS/Babylon.js/blob/master/src/Gizmos/planeRotationGizmo.ts#L104


var localPlaneNormalTowardsCamera = new Vector3();


var tmpSnapEvent = { snapDistance: 0 };
var currentSnapDragDistance = 0;
var tmpMatrix = new Matrix();
var tmpVector = new Vector3();
var amountToRotate = new Quaternion();
this.dragBehavior.onDragObservable.add((event) => {
    if (this.attachedMesh) {
        if (!this.attachedMesh.rotationQuaternion) {
            this.attachedMesh.rotationQuaternion = Quaternion.RotationYawPitchRoll(this.attachedMesh.rotation.y, this.attachedMesh.rotation.x, this.attachedMesh.rotation.z);
        }


        // Remove parent priort to rotating
        var attachedMeshParent = this.attachedMesh.parent;
        if (attachedMeshParent) {
            this.attachedMesh.setParent(null);
        }


        // Calc angle over full 360 degree (https://stackoverflow.com/questions/43493711/the-angle-between-two-3d-vectors-with-a-result-range-0-360)
        var newVector = event.dragPlanePoint.subtract(this.attachedMesh.absolutePosition).normalize();

‘’’

I keep the calculation with the quaternion and set back the Euler angle here :
‘’’

github.com

BabylonJS/Babylon.js/blob/master/src/Gizmos/planeRotationGizmo.ts#L178


    Quaternion.RotationYawPitchRollToRef(tmpVector.y, -tmpVector.x, -tmpVector.z, amountToRotate);
}


if (this.updateGizmoRotationToMatchAttachedMesh) {
    // Rotate selected mesh quaternion over fixed axis
    this.attachedMesh.rotationQuaternion.multiplyToRef(amountToRotate, this.attachedMesh.rotationQuaternion);
} else {
    // Rotate selected mesh quaternion over rotated axis
    amountToRotate.multiplyToRef(this.attachedMesh.rotationQuaternion, this.attachedMesh.rotationQuaternion);
}


lastDragPosition.copyFrom(event.dragPlanePoint);
if (snapped) {
    tmpSnapEvent.snapDistance = angle;
    this.onSnapObservable.notifyObservers(tmpSnapEvent);
}


// Restore parent
if (attachedMeshParent) {
    this.attachedMesh.setParent(attachedMeshParent);
}

‘’’

But the Mesh.rotationQuaternion is not updated once you change the Mesh.rotation with code. Only the Quaternion to Euler works when using the Gizmo. So the 2 rotations are out of sync. Which might not be what you want ?

aWeirdo · July 30, 2019, 12:11am

Hi @Cedric
Thank you, i think this could work.
I only have my phone atm, but i’ll look at it tomorrow.

Cedric · July 30, 2019, 12:12am

Great! Then, I’ll do a PR if that’s what you need.

aWeirdo · July 31, 2019, 4:58pm

Hi @Cedric, I apologize for my poor responsiveness, busy few days.
Did you make any progress on this? i was unable to find a PR.

Cedric · July 31, 2019, 4:59pm

Hi @aWeirdo

I’m making the PR today

aWeirdo · July 31, 2019, 5:04pm

ok.
I made a local fix which i just updated & threw in a PG, as i was unsure if you had gotten around to it yet not fully back-compat.

https://playground.babylonjs.com/#E7GCJK

Cedric · July 31, 2019, 6:32pm

Here is the PR:

Cedric · July 31, 2019, 8:47pm

@aWeirdo It’s merged. It will be in nightly tomorrow

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PlaneRotationGizmo - use rotation if quaternion is null

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