Apply bone orientation and position to mesh without attaching

[Stalker]

Hi!

 

In my scene I have multiple instanced robots with single skeleton. When two of them get near enough each they should start shooting lasers.

 

Skeleton has a bone named "Arm.Gun L", its position and orientation already define the origin from where the laser is shot and its direction vector, the problem is that I can't find a way how to access the data. It need to be accessed and copied only once.

 

Find the bone:

this._bone = skeletons[0].bones.filter((b: BABYLON.Bone) => {	return b.name === "Arm.Gun L";})[0];

And when firing:

var l = this._laser.createInstance("l");l.position = ? // this._bone.?l.rotation = ? // this._bone.?

After looking through the docs for Bone and InstancedMesh (together with its base classes Mesh and Node) the only useful thing I found are local and globalMatrix methods on bones (if I could apply localMatrix to laser would probably do what I want with some minor fixes), but haven't found any efficient way of applying to a laser.

[JCPalmer]

Look at the matrix.decompose() method, for translation, rotation, & scale breakout.

[Stalker]

Didn't really thought using it like this. Smart!

Thanks, it works !

[Stalker]

If I may bug you for one more thing regarding this...

After searching through the forum (problem about rotation), I found out that Bone is presented like a point, so there isn't really any direction in which is facing.

 

I used the code bellow to get rotation, scale and translation.

var l = this._laser.clone("l");var s = BABYLON.Vector3.Zero();var r = new BABYLON.Quaternion();var t = BABYLON.Vector3.Zero();this._bone.getWorldMatrix().decompose(s, r, t);l.position.copyFrom(e.position.add(t));l.rotationQuaternion = r.clone();

Right is the result in BJS (red thing is added), and left how bone looks like in Blender. In BJS it should be rotated ~90deg by Y axis, so that it's parallel to the gun barrel.

That bone is the last one, so I can't use next descendant to calculate direction vector.