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djlane
11-27-2005, 04:38 PM
Ive been storing a quat value in an objects userproperties, like this:

setUserProp $Box01 "QUAT" $Torus01.rotation

which works fine but I think that this has converted the quat into a string.

so when I try to retrieve it from the user properties and use it as a quat again
Maxscript will say Unable to covert to type:Quaternion.

This is what the string looks like:

"(quat -0.164006 0.0264648 0.274527 0.94712)"


I`ve been trying to use the userproperty in a rotation script like this:

VAL = getUserProp $Box01 "QUAT"
VAL

So I suppose I am asking how do I convert a string back to a quat, as quat does
not work.

Thanks for reading

Dan
marktsang
11-27-2005, 05:55 PM
hi,
to turn the string back to a quat you could execute it

blah = "(quat -0.164006 0.0264648 0.274527 0.94712)"
bleet = execute blah

$.rotation = bleet

mark
djlane
11-27-2005, 06:53 PM
Cheers,

That worked great.

Dan
PEN
11-27-2005, 08:04 PM
Can I suggest another plan of attack. Don't use the userProps to store it. Create a custom attribute and store the quat there so that you can store is as a quat and not a string. Then there is no need for the conversion from quat to string and back again.
djlane
11-28-2005, 01:15 PM
Hi Paul,

I thought about that but ( I am showing my ignorance here) I was not sure how
to go about that. As a quat value has the word "quat" in it plus brackets so I didnt think a CA spinner could store it.

Is it easy to do?

Thanks

Dan
PEN
11-28-2005, 04:55 PM
You are not storing the word quat you are storing a quat value. Also you don't need a spinner but you do need to write your own CA def. As it turns out you can't directly store the quat you need to store a matrix. You just need to convert the quat to a matrix and then store it.


b=box()

--CA Def
def=attributes quatHolder
(
parameters params
(
matrixValue type:#matrix3
)
)

--Apply the def to the object
custAttributes.add b def

--Set the value of the matrix3
b.matrixValue=(quat -0.707107 0 0 0.707107) as matrix3

--Use that value to set the rotation of the box
b.rotation=inverse b.matrixValue.rotation


Let me know if that makes any sense to you.
djlane
11-28-2005, 05:33 PM
Thanks it worked great,I tried the example and I was able to get and set the matrixValue CA. would this way be faster for max to do rather than the converting string solution using execute?


Cheers

Dan
PEN
11-29-2005, 12:59 AM
You really want to try avoiding using execute. Best way that you could test it is read it in using a loop and a timeStamp and test to see how long both methods take.
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