Axis Angle To Euler (meulerrotation) --solved

[duckspeaker]

Looks like I should be able to use MEulerRotation API to convert my Axis Angle to (Maya required) Euler Rotation.
But I've never loaded an API...and I'm having trouble.
(I'm looking HERE)

My input would look something like this: axis="0 0 1" angle="39.90397"
(it's XYZ)

And I expect to do something like this:

CODE
     import maya.OpenMaya as OpenMaya
      TestOutput = OpenMaya.MEulerRotation (39.90397, kXYZ)
      print TestOutput

I'm clearly not doing this right...
Can anyone point me in the right direction?

[duckspeaker]

(I was out of town for a while...but I'm back now)

Kinda' solved.
Still no idea how to use an API

Found this:
X = atan2(y * sin(angle)- x * z * (1 - cos(angle)) , 1 - (y2 + z2 ) * (1 - cos(angle)))
Y = asin(x * y * (1 - cos(angle)) + z * sin(angle))
Z = atan2(x * sin(angle)-y * z * (1 - cos(angle)) , 1 - (x2 + z2) * (1 - cos(angle)))

(the above assumes radians)
Import math
Fill in the blanks and I'm golden.

(I still need to look into API usage at some point)

[joojaa]

Well yes your original code snipet make sno sense. It does not fulfill a single one of the constructors provided. In any case worg tool.

CODE
X = atan2(y * sin(angle)- x * z * (1 - cos(angle)) , 1 - (y2 + z2 ) * (1 - cos(angle)))
Y = asin(x * y * (1 - cos(angle)) + z * sin(angle))
Z = atan2(x * sin(angle)-y * z * (1 - cos(angle)) , 1 - (x2 + z2) * (1 - cos(angle)))

Yes but pythonically slow. Be warned tough your not actually chekking for the singularities very well. (for stable code sin and cos statements should allways be chekked for range in values and other calucative singularities chekked for validity. A hard lesson is probably going to be at the end of not doing this.)

[duckspeaker]

QUOTE(Joojaa @ 07/07/09, 06:13 AM) [snapback]310919[/snapback]
Yes but pythonically slow. Be warned tough your not actually chekking for the singularities very well. (for stable code sin and cos statements should allways be chekked for range in values and other calucative singularities chekked for validity. A hard lesson is probably going to be at the end of not doing this.)

That's an interesting point...I should check to validate my variables.
In this instance...They have probably already been proven though.

I tried a "real world" test this weekend.
The application started to slow down around 3000 referenced and instanced (though low-poly) objects....and was running very slow around 20,000 referenced, and instanced (of varying, but still low-poly) objects.

The speed is probably a result of low system memory...at about 3000 objects, I'm really pushing the 3gig of memory on my machine (Win XP64 and Maya take up 8/10 of the first gig by default)

I wonder if my small script is bleeding memory as it iterates through the XML. I'm not sure how Python in Maya handles garbage collection.

[joojaa]

QUOTE(Duckspeaker @ 07/13/09, 10:40 PM) [snapback]311479[/snapback]
I wonder if my small script is bleeding memory as it iterates through the XML. I'm not sure how Python in Maya handles garbage collection.

It probably is. Turn undo off.

[duckspeaker]

QUOTE(Joojaa @ 07/13/09, 01:54 PM) [snapback]311484[/snapback]
It probably is. Turn undo off.

Excellent response.
It's exactly what I did after speaking with a Flash Programmer I know.

Now...my memory is in check the entire process.

However the slow-down is still occurring.
I now wonder if it might be related to HOW maya handles instances.

I created a file of a small (maybe 75 faces) object instanced 3000+ times.
The resulting MB file takes a VERY long time to load.

[joojaa]

Use particle instancing!