Advanced Question Matrix to Euler angles

[Bibi Uncle]

Hi everyone!

I need to rotate a ship at its creation by a given angle of pitch, roll and yaw. I send a VECTOR3 that looks like this: _V(90, 0, 0), and my method should rotate the created vessel.

I have no knowledge of Euler angles, and only basic knowledge of matrices.

I managed to create a matrix that rotates the mesh correctly (tested with SetRotationMatrix). However, calling SetRotationMatrix leads to a little "popping" of the mesh (Orbiter doesn't refresh the matrix in the same frame?).

So, I would like to apply the matrix before creating the vessel: in VESSELSTATUS::arot. However, converting the matrix to the Euler angles does not work. I use the described formula in Orbiter API's documentation:

alpha = atan2(R23, R33)
beta = asin(R13)
gamma = atan2(R12, R11)

The results are weird. I can't find any consistency.

What am I doing wrong?

 

[martins]

This may have been a typo in the documentation. It should be

beta = -asin(R13)

(Hint: You can check that for yourself by solving the equation in the documentation for VESSEL::GetGlobalOrientation for alpha, beta and gamma).

Does that produce better results?

 

[Bibi Uncle]

Thanks Martin! It's working now with your correction! You should correct it from the doc. I verified and there is a typo in the 100830 version of the API_Reference.chm and API_Reference.pdf.

:thankyou: