I decided to re-create an object I own in the game second life to POVray.
The coordinate system and rotations appear to match up more or less. Anyway
one object had three different rotations. I repeated the rotations in povray
and got an entirely diferent final angle. Now each rotation ( along the x,
y, and z axi's)individually, rotated identically.
e.g. a 20 degree angle along the  X axis matched a 20 degree angle in POVray

It was when taken together that they failed to match the expected rotation.
(<20,33,16>)

I then tried three rotations ( each with just one of the rotations)
for example
<20,0,0>
<0,33,0>
<0,0,16>
and still didnt match. I then swapping the three rotations and got different
final angles but none of them matched the expected final angle.
Has anyone tried to re-create secondlife objects in POVray and met the same
problem? Is there a solution?
straight object to object conversion should be possible, you'd think.

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Barehunter wrote:
> Has anyone tried to re-create secondlife objects in POVray and met the same
> problem? Is there a solution?

I'm guessing that in SL, after you rotate the object, the axis around 
which you rotate is also rotated and in POV it's not, or vice versa.

Try turning on the axes display in SL, rotating a prim, and seeing if 
the prim's axis has changed. I believe it *does* change in POV, but not 
SL, altho it has been a while.

-- 
   Darren New / San Diego, CA, USA (PST)
     The primary use of XML is as a technique
     to avoid documenting your interchange formats.

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Barehunter nous apporta ses lumieres en ce 2007/08/15 11:23:
> I decided to re-create an object I own in the game second life to POVray.
> The coordinate system and rotations appear to match up more or less. Anyway
> one object had three different rotations. I repeated the rotations in povray
> and got an entirely diferent final angle. Now each rotation ( along the x,
> y, and z axi's)individually, rotated identically.
> e.g. a 20 degree angle along the  X axis matched a 20 degree angle in POVray
> 
> It was when taken together that they failed to match the expected rotation.
> (<20,33,16>)
> 
> I then tried three rotations ( each with just one of the rotations)
> for example
> <20,0,0>
> <0,33,0>
> <0,0,16>
> and still didnt match. I then swapping the three rotations and got different
> final angles but none of them matched the expected final angle.
> Has anyone tried to re-create secondlife objects in POVray and met the same
> problem? Is there a solution?
> straight object to object conversion should be possible, you'd think.
> 
> 
> 
In POV-Ray, the rotation is applied successively to the 3 axis X, then Y, then 
Z. The axis never change during that operation: rotate about X, from where you 
ended, rotate around Y, then around Z.
Second Life may use another sequence.
It may use a rotating refference axis set. Rotate around X, and Y and Z change 
place, if you then rotate around Y, then X and Z will turn around Y. Same thing 
for Z. In that case, after the Y rotation, your X and Z will have changed. You 
may try the vreorient() macro from transform.inc. (not sure about the exact 
spelling, I've never used that include)
There is also another possibility: The angles are applied all at once in a polar 
coordinate system! In that case, a non-rotated object is rotation <0,90,90>. 
This mean that a point along the X axis is at 0 degree from the X axis, 90 
degree from the Y axis and the Z axis on a polar coordinate system.
Thus, in your case, a rotation of <20,33,16> mean take a vector from the origin 
to a point on the X axis, rotate it 20 degrees away rfom the X axis. Keeping 
that angle constant, rotate it 33 degrees away from the Y axis and 16 degrees 
away from the Z axis.
Using that convention, NOT all combinations of X,Y and Z values are possible: 
<10,10,10> is not deffined.

-- 
Alain
-------------------------------------------------
I find that the harder I work, the more luck I seem to have.
Thomas Jefferson

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"Barehunter" <nomail@nomail> wrote:
> I decided to re-create an object I own in the game second life to POVray.
> The coordinate system and rotations appear to match up more or less. Anyway
> one object had three different rotations. I repeated the rotations in povray
> and got an entirely diferent final angle. Now each rotation ( along the x,
> y, and z axi's)individually, rotated identically.
> e.g. a 20 degree angle along the  X axis matched a 20 degree angle in POVray
>
> It was when taken together that they failed to match the expected rotation.
> (<20,33,16>)
>
> I then tried three rotations ( each with just one of the rotations)
> for example
> <20,0,0>
> <0,33,0>
> <0,0,16>
> and still didnt match. I then swapping the three rotations and got different
> final angles but none of them matched the expected final angle.
> Has anyone tried to re-create secondlife objects in POVray and met the same
> problem? Is there a solution?
> straight object to object conversion should be possible, you'd think.



Did you ever find a solution to this?

Johanna Yascinth can seemingly recreate whole scenes from second life to
POVray..

http://johannahyacinth.blogspot.com/2007/02/weeks-work.html

I would be interested to find more information on this.

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