ive been modeling a city masterplan for an architecture project and Im a bit stuck. ive traced round all the buildings roads and fields with the (Ctrl + left click) tool. ive been adding the faces by selecting all the vertices (points?) and then pressing F to create a face.
now what i want to do with it is drape it over a very detailed landscape, I think you do this with the shrinkwrap modifier? but ive realised that the faces Ive created on my trace over arnt subdivided at all. but when i try to subdivide them it only adds more vertices to the edges, whats going on!? :frowning:

The answer is simple: Bmeshes, a.k.a. Ngons. In other words, when you pressed “F”, you created a single face with a contour made of a bunch of vertices. That’s what Blender does when you press “F”… altho, unless they have a good reason, people avoid to select more than 4 vertices at once so that Blender makes a quad.

The only solution is to select your giant face, “X” -> “Face only”. And restart doing faces (plural!), 4 vertices at a time. In the end, your mesh should look like a grid with some missing faces.

Your’e doing this hard way. Try Bsurfaces addon. F2 (spider script) does create face by selecting just one vertice. Bridge subdivided parallel parts of traced outlines and loop or knife cut across. You’ll get it back much faster using these tools.

The rookies must suffer. That’s the way we all learn. When something is a pain the mouse, we try to avoid it… :smiley:

More seriously, I didn’t know about this add-on. Fascinating…

amazing! :slight_smile: ill try it out today! that should help me shrink wrap it to the terrain im using!

ok. ive tried it out and i cant figure out what im doing wrong. ive taken all the edges that im left with and ive deleted all the faces. then i used the b-spline tool and selected all variations of the settings as well as the automatic join and only a few faces seem to get filled in. im sure theyre all joined as when i pushed F to create faces all the faces were created… just not the way id like…

Do not use Bsurfaces on all the mesh at once. Order of the selection of curves or mesh lines forming surface is important. If for some reason that will be 1,2,5,3,4 e.g., that’ll produce a mess. See this video at 2:00 about Open surfaces.
You might want to separate isolines to later select them in the right order.

Also this video about retopology is worth watching - you told that you already have very detailed landscape model

does this only work with the greese pencil? ive been using ctrl click? also, whats an isoline?

ive noticed theres a little tab that comes up in the video called surface sketching… i dont get that on mine at all…

this is what i have.
I just used the control and click method to trace over a background image of a masterplan. i didnt do it freehand since I thought that accuracy wise doing it with streight lines would be easier. as you can see ive modeled the terrain already using contour lines (i also used the control and click method to do this). I then applied an image displacement to the terrain to give it a more detailed geography. I just want to drape this masterplan over it so i can start to extrude the buildings and colour the paths and grass etc.

also im really sorry for how frantic i sound but i need to get this done by sunday :frowning: uni deadlines… Also also. i really appreciate your help :slight_smile:

heres another picture of what i have with the splines showing.

heres another picture of what i have with the splines showing.

ok. im going to try just making faces the same way i did before but then triangulating them all so that they can be subdivided and shrink-wrapped over the terrain. if there’s a better way to do this please let me know. also. is there a way of highlighting all the outlines of the buildings so that when it comes to extruding them i can find them again amongst all the mess of triangulation? I also would like the top of the buildings to be level. so is there some tool that i can use to tell a bunch of separate faces/ splines to all go to the same z position?