operations on rotations/quaternions and celx

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Rjp buisson
Posts: 31
Joined: 18.03.2002
With us: 22 years 8 months
Location: Paris France

operations on rotations/quaternions and celx

Post #1by Rjp buisson » 13.05.2004, 16:06

I am now trying to understand rotations/quaternions manipulation in lua-celx.
Concerning the document:
Celx Objects and Methods (for Celestia version 1.3.2)
(file version 1.5 -- April 26, 2004) availaible on Don site,
I have a few questions:

1- is there a observer:getoriention() or observer:getrotation() method available?

2- what difference (in effect and in parameter type) between
observer:setorientation(rot1)
observer:rotate(rot2)

3-there are 4 diferents binairy operators with 'rotations':
rot1+rot2
rot1*rot2
rot1*scalar
rot1*vector
Are the definition of the first 3 operators conform to the corresponding operators on Quaternions (algebra structure)?

4- what is the definition and meaning of the 4th mixed product (rot2= rot1*vector ) ??

Thanks to all of you...
JPierre.

don
Posts: 1709
Joined: 12.07.2003
With us: 21 years 4 months
Location: Colorado, USA (7000 ft)

Post #2by don » 13.05.2004, 22:27

Some of your questions may be answered by Harald's complete HTML version, located at: http://www.h-schmidt.net/celestia/lua-summary-1.1a.html

Hopefully he will be able to answer your other questions. I'm still learning Lua/Celx myself. :)
-Don G.
My Celestia Scripting Resources page

Avatar: Total Lunar Eclipse from our back yard, Oct 2004. Panasonic FZ1 digital camera (no telescope), 36X digital zoom, 8 second exposure at f6.5.


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