Extrude part of objects makes error with displacement

[kevin1998223]

Hi, newbie here.
I'm using octane render and find out this problem while messing around, so I simply grab a cube to do some testing.
We can see only the part I extrude made these weird line that didn't cover the whole cube. (This can be fixed with projection but it still feels wrong to me cause it's just a simple object still)
https://imgur.com/a/Z94TEBD
And when I apply displacement on it, the part disappear entirely.
https://imgur.com/a/YPMIqoe

I can't figure out what exactly cause this. I'd done research and seeing someone else talking about it's two points that doubled confused the render engine or something like that, but it doesn't connect to me if a simple extrude cause this.
Can anyone explain the reason, and how to fix this? Appreciated!

[affixxius]

The lines you see are the texture stretching due to the UVs changing when you extruded. Same thing with the displacement. Before texturing, you must consider whether you have correct UVs.

This vid might help with UV basics

https://www.youtube.com/watch?v=O72fjPg ... 72fjPg4YX8

I hope this helps, good luck!

[kevin1998223]

The lines you see are the texture stretching due to the UVs changing when you extruded. Same thing with the displacement. Before texturing, you must consider whether you have correct UVs.

This vid might help with UV basics

https://www.youtube.com/watch?v=O72fjPg ... 72fjPg4YX8

I hope this helps, good luck!

Oh thanks!
I found out the problem on my side is that I never noticed there's another projection tag under the texture tag during watching the video, and I used to only use the projection node in octane texture.
Problem solved, huge thx!