Suggested convenience function

[aitzolmuelas]

I have recently needed to use the method CalcAverageOmega from dgQuaternion to solve part of my custom character controller (worked quite fine by the way). The thing is I didn't want to have any more access to the internal c++ libraries, only Newton.h, so I added a function to Newton.h/cpp which I think is quite convenient (to avoid having to expose dg math library). I don't mind keeping this as a local change, but maybe it would be a good idea to add it to the official releases

Code: Select all

NEWTON_API void NewtonBodySetAverageOmega (const NewtonBody* const bodyPtr, const dFloat* const q0, const dFloat* const q1, dFloat inv_dt)
{
   TRACE_FUNCTION(__FUNCTION__);
   dgBody* const body = (dgBody *)bodyPtr;

  dgQuaternion quat0( q0[0], q0[1], q0[2], q0[3] );
  dgQuaternion quat1( q1[0], q1[1], q1[2], q1[3] );
   dgVector vector ( quat0.CalcAverageOmega( quat1, inv_dt ) );
   body->SetOmega (vector);
}


Also a function to set omega as a quaternion instead of euler angles would be convenient: I don't know about everyone else, but in the engine I'm currently working on almost everything is kept as quaternions.

[Julio Jerez]

CalcAverageOmega is in the dMath library.

[aitzolmuelas]

Yeah, I know, I was suggesting exposing it in the pure C newton interface

[Julio Jerez]

they are in the dMath class: ..newton-dynamics\packages\dMath\dQuaternion.h
you can just use the small library for you own persona usages.

The reason I do not like to add special function for resetting velocity, because there are many different permutations, to me SetOmega and GetOmega, let the use do what ever it need

[aitzolmuelas]

Fair enough. It was just a suggestion, but I can see your point that it would over-complicate the API.

[lperkins2]

How about creating a second, separate pure C header to hold the C wrappers for various utility functions? Something like <NewtonUtils.h>, which would leave the engine API as simple as possible, while not needing everyone to write their own C wrapper functions to use the utility packages.