@cwhite
Thank you for the advice! This was really helpful.
As you mentioned, I didn’t notice the relationship with the translation limits.

I also think I now understand the concept: it’s not the actual “Motor” (the rotation anchor) that translates, but the constraint itself.
And the Motor is like just a additional soft constraint goals setting for position & rotation, rather than actual "Motor".
This is exactly what I was looking for! (as I mentioned in the background).

Now I can tightly constrain its position along a single axis (by increasing the stiffness of the Translation Limit),
while keeping its position with a bouncy effect (by lowering the damping of the Motor Position),
all within a single constraint relationship.

Thanks again for sharing your knowledge!

Hello,
does anyone know what the “Motor Target Position” inside the in Cone Twist Constraint actually means and how it works?
The documentation [www.sidefx.com] doesn’t really clarify it for me, and when I tried adjusting its values or changing my setup, I couldn’t see any noticeable difference in the results — the object itself or motor's rotation axes didn’t seem to be affected in any way.
I also haven’t been able to find any example scenes that make use of it.
If anyone has insight, I’d love to hear it.


Background:
What I’m really trying to build is something like a wheel with suspension that only moves along a single axis, and that led me to this attribute.
A bit of a side note, but although the official Car Rig SOP makes use of the Translation Limits property, when I try to apply it to achieve a bouncy motion strictly along a single axis, it doesn’t seem to allow for it—even if I tweak the Range or Stiffness—and it still tends to drift into the other axes.

So if I want to completely lock the motion outside of one axis, do I basically need to combine it with a slider constraint or use condir/condof?
The problem is that a slider makes it tricky to softly constrain to a single point along the axis, while condir/condof forces me to set it up for every other constraint, which I’d like to avoid if possible.

Sorry for the long background, but if anyone has advice on this as well, I’d really appreciate it.

Also +1 on this.

Migration to Vulkan in other softwares (such as TouchDesigner) is turning out really great on macOS.
Of course, native Metal support would be ideal, but I believe Houdini can achieve something similar.

Currently, the viewport in macOS lacks many of its functionalities or has very poor quality.
(like blooms, ambient occlusion, casting shadows)

I somehow believed that the 20.5 Vulkan update aims to address these issues and bring parity with the PC...
I'm genuinely looking forward to future support on this.

johnmather
Vulkan is unfortunately not supported on Apple silicon at this time due to macOS lacking native Vulkan support. We hope to change this in a future version.

Oh no... But thank you for making it clear.
Really hoping to see this in future!

I found Vulkan not selected by default, even not selectable in preferences.
Is it because of my Mac environment?(M2 Ultra)
I couldn't find anything written about this limitation.

**
TBH, I was really looking forward about Vulkan update in 20.5, since there was significant difference in viewport between PC and Mac.
(such as enabling bloom FX, quality of shadows and ambient occlusion, etc...)

Used 5-6 hours each for a few days, and it's been great! Huge thanks.

Hi Rob,
Thanks for letting us know about the situation inside SideFX.
Though I can't believe since I've seen many same situation around me, but now I will try to make some scene file (maybe with python script) that can reproduce the problem in stable, constant time.

I use intel Mac Pro, and have same problem through H18~H19.
The program runs perfectly fine under a hour after launch, but soon becomes sluggish.

I was told this setting below when I asked for support once.
It made situation a little better in my case. (though mainly remained)

inside Houdini.env:

I'm using macOS 12.1, but I think situation hasn't changed since 11(BigSur).

I'm not sure if it's related, but feels just like the same here.
There are no specific errors, but it gets slower and slower over time.
Typically after using around 1 hours or so, I won't be able to drag the viewport smoothly.(or even inside the network view)
Only thing that helps is to restart Houdini.

Once when I asked for support about this, I was told to set this inside Houdini.env:


It got a little better than before, but the situation still remained.
It seems to solve some problem inside viewport, not around UI.
I hope SideFX could look into this someday seriously.

I gathered two ways of merging shapes in hip.
Method A is an idea from yone80 (https://twitter.com/yone80).
Thank you for all the help.

Thank you vusta! This is simple and solid.
I've recieved some advices on twitter when using boolean in this situation, so I will share it here later.

Thank you BabaJ for the great example, it teaches me a lot. (I love wrangling)
I didn't know a usage of functions like intersect_all().
Now I'll start dealing with about how to make these methods work in any shapes or numbers of curves…

Thank you ndickson for the great help.
I understood about Hole SOP and the bridge, not to get errors in inner boundary.

And thanks for the long try with NURBS.. didn't know about trim SOP yet, so I'll try dealing with it.
Also will try to avoid NURBS too. All I want is to keep the vector shape as it is.
It is fine using either bezier curves or polygons.

I'm trying to find a procedural way to combine multiple curves in Houdini.
And for the first step, I tried to combine multiple circles as below, but couldn't make it happen..
(image above is done by Adobe Illustrator)

–

Here's a process i've been through.

At firt, I made a simillar state in Houdini. Still not combining.(#01)


Next, I tested combining only two circles. And It worked well.(#02)


And I tried to merge two states above using for-loop. (#01 and #02)

It works like combining curves one by one. Seemed it worked, but after 5 times of iteration, whole curve broke. This is because curvesect SOP's Keep Even/Keep Odd settings need to be changed depending on curves' positions or shapes. And I couldn't control this in any ways…


After a while, I came up with another method.
Which is to convert and combine as polygons first, then convert them again as NURBS.

Even though curves have to be resampled, worked well than the previous way.
(Boolean SOP is used for self-intersections, so I used left input only)


But when iteration comes to the end, center area gets filled with polygon.I tried Hole SOP couldn't resolve this.

If possible, I want to avoid converting/resampling as polygons or VDBs, and keep them as curves during operation.
(so the shapes won't change and keep accuracy)
Curvesect SOP was really nice but couldn't determine EVEN/ODD settings…

Sorry I'm new to Houdini, and my English is poor.
It would be really appreciated if you could give me any advice. Thank you.