Forums Technical Discussion Wiresolver & orient

Wiresolver & orient

   2460   10   1
User Avatar
Poulpito
Member
25 posts
Joined: Nov. 2013
Offline
 
Hi,

First, sorry for my english.

I can not recover the orientation of the point of simulation wire simulation.

I begin on Houdini mais i'm sure there is a simple solution to my problem.

Attachment Not Found


H16.5


Thank you.

Attachments:
test_animObjGeo_Q.hipnc (129.7 KB)

 Report
User Avatar
derrick
Staff
329 posts
Joined: July 2005
Offline
 
The orientation of each point in /obj/geo1/dopnet1 can be read from the “orient” point attribute. The attribute value is a quaternion describing how the geometry has rotated relative to its rest pose. /obj/geo1/copytopoints2 uses this attribute to orient each control.
 Report
User Avatar
Poulpito
Member
25 posts
Joined: Nov. 2013
Offline
 
Yes, I understand but my geometri is not at rest. She is animated.
The orientation is therefore incomplete. (local and not global)

I'm trying to recreate an orientation with PolyFrame but they flip.
 Report
User Avatar
derrick
Staff
329 posts
Joined: July 2005
Offline
 
I think I now understand what you are trying to do. Since the original geometry does not contain an “orient” attribute, the Wire Solver assigns a default value (the identity rotation) which isn't aligned to your geometry on most frames. You should provide an explicit “orient” attribute (see /obj/example/attribvop1 in the attached example).

Attachments:
test_animObjGeo_Q-2.hipnc (156.3 KB)

 Report
User Avatar
Poulpito
Member
25 posts
Joined: Nov. 2013
Offline
 
Ho yes, thank you.

In reality my animation comes from a alembic.
It is enough for me to extract the orient with primintrinsic(), i believe.
 Report
User Avatar
Poulpito
Member
25 posts
Joined: Nov. 2013
Offline
 
Hello,

Is it possible to find the position of a point in the world ?

Because for cable or other grain simulation, it's complicated for me to recover an animation of the object.
I come from 3ds Max where a simple link does the job.

Thank you.
 Report
User Avatar
derrick
Staff
329 posts
Joined: July 2005
Offline
 
How is the value you are wishing to obtain different from the “P” attribute? Could you post an example .hip file?
 Report
User Avatar
Poulpito
Member
25 posts
Joined: Nov. 2013
Offline
 
Sorry ^^

My question is clumsy, or my english.

Attachments:
p_world.hipnc (65.7 KB)

 Report
User Avatar
Poulpito
Member
25 posts
Joined: Nov. 2013
Offline
 
Hello,

I come back to my orientation problem.

I have prepared a scene that illustrates a part of my problem.
On this example add an @orient not sufi.

Would you have a solution?

Attachments:
copyorient_01.hipnc (144.1 KB)

 Report
User Avatar
derrick
Staff
329 posts
Joined: July 2005
Offline
 
If I understand what you are trying to do, the initial orient values do not match what you want them to represent. The Copy SOP applies the minimal rotation to align the geometry's Z-axis with each template point's normal but you want the orient values to reflect the rotation described by /obj/coil/transform2.

Disconnect the transform2 node then place it between the copy1 and OUT_wire nodes. This will cause the rotation to be applied to the orient values as desired.
 Report
User Avatar
Poulpito
Member
25 posts
Joined: Nov. 2013
Offline
 
I am sorry, I thought I had found an example that would explain a bug on my real scene. But no.^^

In reality, the lines are animated and then imported into Houdini in alembic.
I am then obliged to extract the orientation of the intrinsic ones for the copy.
But the simulation becomes wrong. May be because of the difference in orientation between these two software.

In the meantime I found a solution:
I merge the orient after the simulation with qmultiply().

Thank you.
 Report
  • Quick Links