1
$\begingroup$

This is my first question here, i'd be so happy if you could help me out!

I'm building a procedural plant generator based on a spiral curve. I scatter the spiral as instances on a mesh, rotation aligned to the base mesh normals. Then i instance leaves on the points of the spiral and set the rotation so each leave is facing outwards from the center of the spiral. That works just fine by providing the vector from curve center to points on spiral and align euler to vector.

But ones i realize the spiral instances, the rotation of the leaves is off.

I did few hours research yesterday without finding a solution. I'm sure it can be solved with vector math, but i'm not good at it yet and also i don't understand what exactly changes with 'realizing instances'. I read the manual regarding this, but i can't wrap my head around what it means and how i have to manipulate vectors in this case to make it work.

I attached screenshots, first one showing desired rotation without realizing, second false rotation after realizing instances. Also i attached a simplified test .blend

Thanks for any help, explanations also highly appreciated!

enter image description here

enter image description here

$\endgroup$
2
  • $\begingroup$ The attached .blend doesn't look quite like on the screenshots, at least on my machine: i.imgur.com/EwGGGDh.png $\endgroup$ Dec 14, 2023 at 10:29
  • $\begingroup$ True, it's a simplified version, i just replaced the modelled leaves with planes, the geo node tree is the same and the rotation issue is visible on the planes as well if you unmute and mute the 'realize instance' node. Thanks for having a look! If you need the original file, i can upload that to, but filesize is bigger and i thought that this smaller files would clarifiy the case. $\endgroup$
    – Rolando
    Dec 14, 2023 at 11:00

1 Answer 1

0
$\begingroup$

Capture the instance rotation before realizing it, then rotate the other rotation by it:

$\endgroup$
2
  • $\begingroup$ Ahhhh, ok, thx a lot! I'll try this later, i'm not on my computer now. Man, i never used to rotate euler node... that really makes sense! $\endgroup$
    – Rolando
    Dec 14, 2023 at 11:55
  • 1
    $\begingroup$ Ok, i ran to the computer to try ;) It works like a charme, thx a lot. Also i'm happy to understand how and why! You saved my day!!!! $\endgroup$
    – Rolando
    Dec 14, 2023 at 12:05

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .