Difference between revisions of "Talk:Rotation"

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Fixed a few minor syntax errors and reworked the top of the article a bit. As an article it is quite far along though it still has a ways to go. [[User:Strife Onizuka|Strife Onizuka]] 03:32, 29 January 2007 (PST)
 
Fixed a few minor syntax errors and reworked the top of the article a bit. As an article it is quite far along though it still has a ways to go. [[User:Strife Onizuka|Strife Onizuka]] 03:32, 29 January 2007 (PST)
  
== Intro is aweful ==
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== Intro is awful ==
  
 
"gymbal lock" is something that affects mechanical systems with gyroscopes.  A quaternion rotation is a mathematical abstraction.  The term simply does not apply, and only serves to confuse things.  The reference to "SLERP" without a link is useless. [[User:Doran Zemlja|Doran Zemlja]]
 
"gymbal lock" is something that affects mechanical systems with gyroscopes.  A quaternion rotation is a mathematical abstraction.  The term simply does not apply, and only serves to confuse things.  The reference to "SLERP" without a link is useless. [[User:Doran Zemlja|Doran Zemlja]]
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Shouldn't the content of this page be moved to Category:LSL Rotation? It seems confusing to me to have multiple Rotation pages.
 
Shouldn't the content of this page be moved to Category:LSL Rotation? It seems confusing to me to have multiple Rotation pages.
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== GetRot()/SetRot() chart ==
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llGetLocalRot() and llGetRot() clearly do *not* return the same value in the root prim of an attachment.  While I believe that llGetRot() returns the avatar rotation as indicated, llGetLocalRot() I believe gives the rotation of the root prim relative to the attachment point (or the avatar?)

Revision as of 18:17, 22 July 2007

Fixed a few minor syntax errors and reworked the top of the article a bit. As an article it is quite far along though it still has a ways to go. Strife Onizuka 03:32, 29 January 2007 (PST)

Intro is awful

"gymbal lock" is something that affects mechanical systems with gyroscopes. A quaternion rotation is a mathematical abstraction. The term simply does not apply, and only serves to confuse things. The reference to "SLERP" without a link is useless. Doran Zemlja

Gimbal lock effects Euler angles to which you wrote an article using them everywhere without mention it; it is a gross oversight. That sentence is a bit complex on review and yes there is no SLERP article but that doesn't mean someone won't write one (it is better to leave open links then no links; no links give no hint that a page should be created). I may write a short one tomorrow, I already have a function that implements it (I've just been pressed for time). I will find a better article on gimbal lock, the wikipedia one is pretty poor in this regard as it fails to go into the programing implications. I gave you the benefit of the doubt and looked up 'gymbal' in the dictionary, to which it was nowhere to be found; but 'gimbal' was. Strife Onizuka 19:33, 31 January 2007 (PST)

Mirroring using quaternions

I think I have worked out how to mirror a point (and therefore an entire object in pieces,) using quaternions, but does anyone here know how to, or if it is even possible to, define a rotation that turns a left hand into a right hand or vise-versa? This is a three diminsional mirror operation, but in four diminsions it is a simple rotation. (I could be wrong, but based on my research into quaternions it seems right...)
Cron Stardust 22:16, 25 March 2007 (PDT)

It depends entirely upon which axis you want to mirror around. Save yourself some work and look up Jeffrey's Prim Mirror. Strife Onizuka 11:13, 26 March 2007 (PDT)

Moving this page

Shouldn't the content of this page be moved to Category:LSL Rotation? It seems confusing to me to have multiple Rotation pages.

GetRot()/SetRot() chart

llGetLocalRot() and llGetRot() clearly do *not* return the same value in the root prim of an attachment. While I believe that llGetRot() returns the avatar rotation as indicated, llGetLocalRot() I believe gives the rotation of the root prim relative to the attachment point (or the avatar?)