Calculate euler angles in DOTS by the Quaternion class

Unity Engine
,
1

Hello everyone!
I use Euler angles to calculate a boolean value:

    public static bool GetIsFlipDirection(Rotation rotation)
    {
        Quaternion rotationValue = rotation.Value;
        var anglesZ = rotationValue.eulerAngles.z;
        bool flipY = anglesZ > 90 && anglesZ < 270;
        return flipY;
    }

Is it a good way to use Quaternion in DOTS? Is it compatible with Burst? I really couldn’t find a way to use Unity.Mathematics to calculate Euler angles.

2

I used this

public static float3 ToEulerAngles(quaternion q) {
    float3 angles;

    // roll (x-axis rotation)
    double sinr_cosp = 2 * (q.value.w * q.value.x + q.value.y * q.value.z);
    double cosr_cosp = 1 - 2 * (q.value.x * q.value.x + q.value.y * q.value.y);
    angles.x = (float)math.atan2(sinr_cosp, cosr_cosp);

    // pitch (y-axis rotation)
    double sinp = 2 * (q.value.w * q.value.y - q.value.z * q.value.x);
    if (math.abs(sinp) >= 1)
        angles.y = (float)CopySign(math.PI / 2, sinp); // use 90 degrees if out of range
    else
        angles.y = (float)math.asin(sinp);

    // yaw (z-axis rotation)
    double siny_cosp = 2 * (q.value.w * q.value.z + q.value.x * q.value.y);
    double cosy_cosp = 1 - 2 * (q.value.y * q.value.y + q.value.z * q.value.z);
    angles.z = (float)math.atan2(siny_cosp, cosy_cosp);

    return angles;
}

private static double CopySign(double a, double b) {
    return math.abs(a) * math.sign(b);
}
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3

@mr-gmg Thank you very much.
I checked the performance of your solution.

[BurstCompile]
iterations: 10000000
Quaternion.eulerAngles   =>  ~670ms
ToEulerAngles()            =>  ~260ms
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