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How do I get the euler angles of bones?


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I'm trying to get the initial euler angles of the bones right when my model is loaded.


I tried this:

bone.getLocalMatrix().decompose(vec1, quat, vec2);


but the values I'm getting in vec3 are not correct.


The angles I want are relative to the parent bone.


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I didn't.  


toEulerAnglesToRef takes a Vector3:

public toEulerAnglesToRef(result: Vector3): Quaternion {            //result is an EulerAngles in the in the z-x-z convention            var qx = this.x;            var qy = this.y;            var qz = this.z;            var qw = this.w;            var qxy = qx * qy;            var qxz = qx * qz;            var qwy = qw * qy;            var qwz = qw * qz;            var qwx = qw * qx;            var qyz = qy * qz;            var sqx = qx * qx;            var sqy = qy * qy;            var determinant = sqx + sqy;            if (determinant !== 0.000 && determinant !== 1.000) {                result.x = Math.atan2(qxz + qwy, qwx - qyz);                result.y = Math.acos(1 - 2 * determinant);                result.z = Math.atan2(qxz - qwy, qwx + qyz);            } else {                if (determinant === 0.0) {                    result.x = 0.0;                    result.y = 0.0;                    result.z = Math.atan2(qxy - qwz, 0.5 - sqy - qz * qz); //actually, degeneracy gives us choice with x+z=Math.atan2(qxy-qwz,0.5-sqy-qz*qz)                } else //determinant == 1.000                {                    result.x = Math.atan2(qxy - qwz, 0.5 - sqy - qz * qz); //actually, degeneracy gives us choice with x-z=Math.atan2(qxy-qwz,0.5-sqy-qz*qz)                    result.y = Math.PI;                    result.z = 0.0;                }            }            return this;        }
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I just notice this comment in the toEulerAnglesToRef function:


//result is an EulerAngles in the in the z-x-z convention 



I'm thinking I'm going have to do some research on how to get an x-y-z euler from a matrix.  Heck, I'll probably just end up hard coded the angles into my code.

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I'm not very familiar with all this, but it seems the conversion from z-x-z to x-y-z convention is pretty complicated.


Basically you're looking to have the yaw/pitch/roll angles of your bone, right? If that's what you specifically need, then I guess BabylonJS doesn't have the right function for you. Although transforming a quaternion to x-y-z euler angles should be as feasible as what's currently implemented.


At any rate, please keep us informed on your progress: rotation issues are common and sometimes complicated, especially with quaternions involved.

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