Hello,
how can I extract only the orientation from this matrix , without shear and scale? The quaternion function seems not to ignore the scales and shears that are stored in the matrix and this leads to different rotations.
I get strange mblur result when I try te calclate the w attribute from this.
thanks
Martin
MPM | Deformation gradient F to orientation
330 2 0-
- sanostol
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- animatrix_
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Hi Martin,
You can do this using the polardecomp [www.sidefx.com] VEX function:
You can do this using the polardecomp [www.sidefx.com] VEX function:
matrix3 R, S; polardecomp ( F, R, S ); vector4 q = quaternion ( R );
Senior FX TD @ Industrial Light & Magic
Get to the NEXT level in Houdini & VEX with Pragmatic VEX! [www.pragmatic-vfx.com] https://lnk.bio/animatrix [lnk.bio]
Get to the NEXT level in Houdini & VEX with Pragmatic VEX! [www.pragmatic-vfx.com] https://lnk.bio/animatrix [lnk.bio]

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