Cylindrical hard surface withouth pinching

Alexaurus3D

Hello! I'm new here, so I'm sorry if this topic is repeated and sorry for my english.
I have a cylindrical mesh with a hole, but when I want to add support edges to make it more rectangular i have pinching as a result.
Which is the best approach to make this kind of hard surface without the pinching? I read in internet the best solution is to add more subdiv but I want to have a low poly mesh.

This is where I want to add the edge supports.


More context of the mesh.

Blue circle is what I want and the yellow rectangle is what I want to avoid.

Thanks in advance!

Ghogiel

the brute force way is have more loops in the vertical cylinder the rectangle is cut into and using the inset method so as to use the existing loops as some of the support loops.

After insetting the rectangle, add support loops. I added some extra support loops (red) on top of this set up to hide the minor warping, I did that because I wanted to use edge constrain and slide the purple loops tighter to the rectangular cut out.

gnoop

You don't need extra loops .  Neither  so hi res cylinders.     You just have to project vertex normals  from a cylinder without hole .   it's a main reason why projecting vertex normals  from one object to another exists.

Alexaurus3D

Ghogiel said:

the brute force way is have more loops in the vertical cylinder the rectangle is cut into and using the inset method so as to use the existing loops as some of the support loops.

After insetting the rectangle, add support loops. I added some extra support loops (red) on top of this set up to hide the minor warping, I did that because I wanted to use edge constrain and slide the purple loops tighter to the rectangular cut out.

Hi! Thanks for the repy! I will try this method, looks very clear now! Thank you!

Alexaurus3D

gnoop said:

You don't need extra loops .  Neither  so hi res cylinders.     You just have to project vertex normals  from a cylinder without hole .   it's a main reason why projecting vertex normals  from one object to another exists.

By this you mean like baking a high poly onto a low poly? I'm a noob, sorry.

gnoop

Alexaurus3D said:

By this you mean like baking a high poly onto a low poly? I'm a noob, sorry.

It may be just your  initial cylindrical object  before  you did  the hole .The one  that you think has perfectly  ok shadings without artifacts.  But yes,   in many cases its easier to transfer vertex normals  from  hi poly object.  

Baking  usually assumes  per pixel  baking into textures.    It's not what I mean .     I am not Maya user   but as I recall  it's called  "Attribute transfer"  in MAya  .  So it's   "transfer"     rather than "baking"     Kind of projection  of  source object  vertex normals to  target  one.

 It's vertex normals  that make surface  shading   so you always can   edit them directly instead of extra loops.   In case of that hole  you could just make hard edge /split  vertex normals  (whatever it's called in Maya) and copy/paste vertex normals from where a vertex  normal is in right direction .       I do so in Blender ( pretty sure Maya should has the option too)      So sometimes  you can quickly cope with that  even without  "transfer" 

ps.   All this is relevant to  low poly in game meshes only.  If you use subdivision modelling   for offline rendering   then yes, extra loops  is a  right  way.