Align Geometry on Spline along TangentU and Y-Axis

[sant0s81]

Hey everybody,

some weeks I made a simple cave builder and it worked great.

But since I only used round circles, it was quite simple.

Now I want to create something similar, but with a flat ground, I attached an image what I mean.

 

Actually, I want to align the shape along the TangentU what works perfect, but at the same time on the Y-Axis so that the floor is correct.

The other thing is, that it makes no sense when the tunnel has a very steep angel, that ther is a floor - so there I want it based on the angel to become from the floor shape to a round shape.

Is it possible, to controll that somehow with a ramp?

Thanks alot and happy easter,

sant0s

Edited April 20, 2019 by sant0s81

[flcc]

For the align topicsmay be you may check this video from entagma : TD Essentials: Parallel Transport.

https://vimeo.com/251091418

 

[LaidlawFX]

Make sure you use the up vector for vertical alignment.

http://www.sidefx.com/docs/houdini/copy/instanceattrs.html

[sant0s81]

Hey, thx alot to you!

I finaly could manage to align the shape in a correct way by setting the Normal to Y.

But I get to another problem now: On some parts of the spline, the geometry is twisted.

Is there a way to fix that or at least, smooth the twist out?

 

Edited April 21, 2019 by sant0s81

[LaidlawFX]

This is a basic setup with using N and up. That I believe is doing what you want on a  figure 8.

Orient.hip

[sant0s81]

Hey @LaidlawFX

sry for late response, but thx alot! Thats great - so much more efficent than my setup.

I ll gonna work on that.

edit:
I am just trying to figure out, how to calculate the angel by normal.
Somehow I guess, I have to use the attribute VOP and create a cross product, at least I am reading all the time about that.

The goal is to get the angel (0° - 90°), feed that into a ramp and use the 0-1 value to control the scale of the circle.
Is that possible with the attribute VOP or only in VEX?

Thx again!

Edited April 24, 2019 by sant0s81