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rotation not Z UP?

paulie Femto
Into the dark
Join date: 13 Sep 2003
Posts: 1,098
10-15-2005 11:04
Umm..maybe Im missin somethin. I did sleep through geometry class. But, why is an object rezzed with a rotation axis of X UP, not Z up?

By this I mean that an object with its rotation at <0,0,0> has its X axis up and down, instead of its Z axis.

This:
http://www.siggraph.org/education/materials/HyperGraph/modeling/mod_tran/3drota.htm
probably explains it, but the math is beyond me.

t just seems like Z should be up with rotation at <0,0,0>.
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Laukosargas Svarog
Angel ?
Join date: 18 Aug 2004
Posts: 1,304
10-15-2005 12:55
Cubes and Cylinders are rezzed z up, I can't see a logic either, especially as OpenGL's default is Y vertical, X horizontal and Z near far. Some objects even rez with X pointing down ! Personally I think they should rez with X fwd, Y left, and Z up, it would prevent me from forgetting to rotate prims to what LSL likes when I'm trying to script movement ;)
Strife Onizuka
Moonchild
Join date: 3 Mar 2004
Posts: 5,887
10-15-2005 13:08
When you take an object the rotation it had when you took it is the rotation it will have when you rez it (with the exception of llRezObject & llRezAtRoot which overrides that). New objects have default rotations other then zero; such as spheres.
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