Jon S Berndt wrote:

> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:flightgear-devel-
> Sent: 15 December 2004 17:34
> To: FlightGear developers discussions
> Subject: Re: [Flightgear-devel] control surface normalization
> On Wed, 15 Dec 2004 17:21:13 -0000
>   "Vivian Meazza" <[EMAIL PROTECTED]> wrote:
> > A quick search revealed that most, if not all, the 3d models in the
> > current inventory use normalized values for animating the control
> > surfaces.
> See, this further raises a red flag for me. How does the 3D model know
> how far to move the aerosurface? What does the "normalized value"
> represent? This requires (like the VRP) more communication between the
> flight modeler and the 3D modeler. Are they both using the same values
> for the maximum angular range for an aerosruface - that is, the value
> that "1" represents? There are software limits. There are hardware
> limits. Which one is being used by the 3D modeler? It seems to me that
> the sensible thing to do is to simply use the angular value provided
> by the FDM - the one that is being used to determine the forces and
> moments. To do otherwise invites errors and confusion, IMHO.

There are several points here. 

1. The fact is that most 3d (I think all, but I haven't checked) rightly or
wrongly already use normalized values. It would be a significant task to

2. I don't think we tell YASim the correct angles to use. Therefore the
normalized output, factored to produce the correct visual angles, is the way
to do it right now.

3. For consistency, and remember that some 3d models are used with both
YASim and other FDMs, we need normalized values.

4. It doesn't matter where the conversion is done. If FG is the only user of
normalized values, it makes sense to do it there. 

I have no doubt that this point was vigorously debated at some point in the
past, and for good reasons we are where we are. We need to revisit those
discussions and revalidate the decisions before making any change.



Flightgear-devel mailing list

Reply via email to