I really dislike having to make tufted furniture. I find it very finicky and limiting. I especially don’t like having to do this kind of tufting that curves both vertically and horizontally. Still, the end result can look pretty good.
Of course you could just do a fairly blocky massing model then throw something like Artisan’s subdivide and smoothe at it, but the poly count would end up being pretty high…so I generally hand-build stuff like this.
The poly count on this is surprisingly low…about 6,400 faces…and that includes the piping and the cushions.
I decided that the way to go on this was to make a single vertical segment of the back, then array it in a curve. Looking at the number of buttons, it seemed that if I created a simple curved back with a segment vertex corresponding to each button (including the offsets in the middle row) then that would give me enough segments to create a decently curved unit.
So I constructed a simple, unstudded model of the back as well as a component of a single dimple.
Then placed copies of the dimple just behind the surface of the back…one for each of the rows. I then physically stitched these together to form a repeatable unit with the bulging, cushioned bits in between…paying special attention to getting that distinctive, diamond shaped pattern of creases running from button to button
I made a component of this and arrayed it in a curve, then manually tweaked any slight mismatching of vertices. Being a component, the tweaks obviously updated right along the whole curve.
The rest of the sofa was a breeze, in comparison.