Rotation of a yarn

[cberkley]

Hi
I am using TexGen to create unit cell weaves for my 3rd year project. I am creating a python script for layered weaves and exporting these to test the macro structural properties.

I am having some problems with the rotate function Rotate (WXYZ (), XYZ ()). I believe the second part is the point at which the rotation occurs but what is the first bit?

I would appreciate some help on this. I am new to TexGen and coding in general

Chris

[louisepb]

Hi Chris,

The WXYZ is a quaternion ( see here: http://en.wikipedia.org/wiki/Quaternion ... l_rotation )

The documentation for creating a quaternion from either a normalised axis and angle, a new coordinate system or euler angles is here: http://texgen.sourceforge.net/api/struc ... x_y_z.html. You need to decide how best to specify your rotation, create your quaternion from this and then use it in the Rotate function.

Hope that helps,

Louise

[cberkley]

Louise
Thank you for your help but it would seem I still have a problem

Code: Select all

Angle=math.radians(12)
Yarn = CYarn(Textile.GetYarn(0))
Yarn.Rotate(WXYZ(XYZ, double Angle), XYZ(1,0,0.225))
Yarn.Translate(XYZ(0, 0, 0.3))
Textile.AddYarn(Yarn)

This is the code I wrote however it produces an error

File \2d weave.py", line 13
Yarn.Rotate(WXYZ(XYZ, double Angle), XYZ(1,0,0.225))
^
SyntaxError: invalid syntax

with the triangle under Angle
Apologies for bugging you

[louisepb]

Hi Chris,

You need to take the double out of the Rotate call. You also need to define the XYZ either in the same way as you've done the second one in the call or by defining an XYZ variable and using that.

Louise