Unit of measurement for directional parameters in the .scn file?

Jorgen

I've long been wondering in which unit directional parameters are given. For example, the sky box can take optional Pos=() and Orient=() parameters. The position is fairly straightforward, but what unit are the Orient parameters given in, and what is the zero reference for the three values? Is it only the X, Y and Z axis, or do GDB parameters such as Latitude and NorthDirection affect things too?

For a directional light source there is a similar Dir=() parameter which I suspect use the same units, right or wrong?
 
Hey Jorgen,
I haven't tested this out at all yet, but according to a tutorial written by Ewan "Uzzi" Chalker the following is:
Explanation of Orientation

(Pitch – up/ down, Rotation – left/ right, Yaw – lean left and right)

Rotate right -
Rotate left +

NE 7
N 6.33
NW 5.54
W 4.75
SW 3.875
S 3
SE 2.33
E 1.66
.3 + 22 degrees
5 degrees of pitch = 0.1
Click to expand...

After doing a little investigation into what these numbers ACTUALLY mean, I found that they're angles listed in radians where N is actually 0 instead of 6.33. To convert from radians to degrees, follow the formula: deg.= rad * 180 / pi. (or rad = deg * pi / 180 to find radians from degrees).

I don't know if the .scn file uses this same convention, I would imagine it does, though. Hopefully, you can figure out the rest from there (other axes and +/- rotation direction), but it sure seems as though they're using radians as their units for angles according to that tut.

-Chris
 
Thanks Chris! Radians makes sense now that I think about it. I always had a feeling it wrapped around somewhere between 6 and 7, but it never struck me why. I've always struggled when aligning the directional light source and the shadows with the sun in the sky dome, but now it should be a lot easier. :)
 
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