By this question, I mean how to build a perfect cylinder (not a subdivided prism) from 2 distant vertices, with a specified radius ? I have been trying so hard to find an easy way to do it.
Thanks if you can help !
Blender Stack Exchange is a question and answer site for people who use Blender to create 3D graphics, animations, or games. It only takes a minute to sign up.Sign up to join this community
There is two simple ways to make an edge into a cylinder, depending on your needs, one will fit the purpose.
The first one is to seperate your edge from whatever else you have in your current object by pressing P > Selection. Then Convert your mesh into a curve (best to search using F3) Object > Convert To > Curve. Then go to the curve setting (green curve in the properties panel) and change the Geometry > Bevel > Depth to your radius and the resolution to your preferred resolution. You could approximate your perfect cylinder by using very high numbers (like 360) sadly though there is a hard limit of 32 on that property (which is enough for most applications).
The second way of doing it is a bit more flexible in construction, but less flexible after it's done (can't really change the resolution without repeating these steps). This time we will stay within the mesh editmode. First select the transform space Normal (e.g. press , > Normal). Then select your edge and put the 3D Cursor on it by pressing Shift+S > Cursor to Selected.Then press E to extrude. Choose the X axis as it's perpendicular to the edge and type in your radius, finish operation. Then select the newly created face and choose the spin tool from the tools on the left (or use Shift+Space). Choose the correct looking axis in the top bar where the tool settings are. You can also already choose the steps there. Then use the tool to make your cylinder (hold ctrl for angle snapping). If your cylinder is looking weird on the inside try changing Auto Merge in the Last Operation Menu (F9). Now remove your internal edge and Merge by Distance (M) if needed and your are good to go.
There is countless more ways to do this actually. Ok heres a bonus way to do it, because its beautiful:
I would use the Skin Modifier. The vertices needs to be connected with an edge. The radius can then be adjusted with skin resize in Edit mode at the vertices.
To add a skin modifier and sds modifier gives of course rounded ends.
To have flat ends, don't use SDS directly. But apply the Skin Modifier. This gives you a box mesh. Then in edit mode remove the upper and lower face, add SDS, apply SDS, and add a face at the top and bottom of the cylinder.
Alternatively, mark the upper and lower edgeloops with a crease of 1 when doing SDS. Then you don't have to remove and readd the top and bottom face.
This is a bit complex but here goes.
in edit mode:
Select one vertex
snap the 3Dcursor to vertex with (Shift s - snap to selected)
exit edit mode
create a circle of the desired diameter and fill with triangle fan. (Shift a) The middle vertex of the triangle fan is needed later for snapping.
select the other vertex (in edit mode in the object with the vertex)
again snap the 3Dcursor to vertex
create an empty (Shift a) select the circle
add an object constraint: track to and select the empty as the target
The circle should now be perpendicular to the line between the two vertices.
now select the circle and enter edit mode of the circle
enable snap to vertex
and finally extrude the circle towards the second vertex.
if needed you can join the objects to create a single mesh.
I home that helps,