Per primitive rotation

[sergio]

Hello everyone, 

 

I am trying to recreate the per primitive rotation example i found here with VEX for learning purposes. The example file uses VOP to calculate a quaternion to rotate the points but when i do it in vex something weird happens and points doesn't behave as expected. I have also used qrotate() but no luck. Can you please take a look at file? Am i calculating the quaternion wrong?

 

Thanks in advance

 

 

Per_prim_rot_vex.hipnc

[sadhu]

Hello Sergio, I am not sure but following seems to be the issue 

 

In your pointvop_rotate_prims, makeinstancexform1 vop has no input P connection. Connect P from global inputs to P param on makeinstancexform1 vop and you will notice that your vop output is matching to vex output. I am guessing when no input is connected to P it assumes (0,0,0) value for P and trans para is taking care of the position. In instance expression, pivot is giving you position so don't need to specify P = @P, set it to (0,0,0).

 

Make following changes in your code. 

vector origin = (0,0,0);

final = instance(origin,@N,scale,rotate,Q,pivot);

Edited April 24, 2015 by sadhu

[sergio]

Yes that's it. I assumed it would default to position if none is fed but apperently it was 0,0,0. Thank you Sandeep, much appreciated.