I have tried many experience like boolean, curves, begin with circle for retopology and extrude, bridge edge loop, Zbrush(zRemesher) and a friend with retopology(snapping).
Have you some idea for that torus ? thanks
(sry for my english language :p)
Are you wanting a flat top and bottom torus with a square hole center? Then extruding a circle will work then scale the inner part of the circle sections to make a square. With a 16 vert circle you would select the top 5 verts of the square and scale on its axis to zero and the same with the bottom section of the circle. Repeat on the sides as well selection the 5 verts at the side of the inner circle and scale to zero. That should now leave you with a circular outside with a square inside. You can then select the inner and outer verts and extrude them down to the thickness you are needing. Fill in the bottom section outer to the bottom section inner. You should now have a torus with a square hole in the center and a rounded outer. You can now add in loops as needed to create the geometry you desire and they will all be equal.
This is a 16 vert circle and subdivision surface of 2 on it. If you want the interior square sharper you can add a mean crease to the top bottom and inside corners of the hole to make it sharper looking.
From those pictures, I don’t think you want that topology. I think you want that UV map. Totally different.
If you use smooth shading, UV textures, vertex color, or CC subdiv-- anything that involves the interpolation of vertex values-- and you don’t have topo that follows the lines of your mesh, it will look bad. There is no getting around that.
So how do you get right.jpg? Well, if you look, not even those tiles look like what you’ve proposed. You get it by making a torus, flattening a few inner edge loops, seaming, and follow-active-quads UV mapping.
How do you get 6c7814e985ccc3d8d723ba84d14ac435.jpg ? With the exact same topology, but with a frontal projection UV map (probably combined with some other mapping techniques to minimize distortion.)