Need a help. I cannot understand if Blender is corrupted or that's okay vertices to work like that

Hello, guys! I cannot say that i am a newbie in Blender, but I noticed weird behaviour after vertices. Let’s say i want to make a cube, apply a subdivision surface on it and then extrude the TOP (just one) vertice. Then I see that edges that conected to that vertice don’t go up proportionally. (I can’t really explain what i mean cause i am not a native speaker :slightly_smiling_face:). How to recreate it in images below). And that happens to absolutely new project. So I wonder, do I have to reinstall
blender or it is how that should be?

Ask you for help. Couldn’t find answers in google. Thanks a lot in advance!

You had proportional editing selected and the distance “includes” the next vertices ??

Hello! Welcome to the forums!

From your screenshot, nothing appears to be wrong with blender. If you want more than one vert to move when you drag that one up, you need to turn on proportional editing. If it’s already on, try middle mouse scrolling to increase the range of influence.

I am concerned about these parts, because it works fine from the other side

And proportional editing is turned off

Faces with 4 vertices are internally handled as triangles. So that its in fact two triangles. You normally dont see it, but for a quad its possible that not all points lie in the same plane. If that happens for a face then you will see the two triangles.

So no its no problem at all.

So for cube that’s fine either?

View from another side

And is there a way to fix it?

Its how GPUs work. Working with triangles has lots of advantages for them. Quad dominant meshes are just nice for modeling, cause it defines an edge flow as render primitive they just cause trouble. :grin:
You can mark the for quads on top and triangulate them, When blender sees them as triangles then you can spin/rotate the edge to lead to your center vertex.

Menu → Face → Triangulate Faces
Menu → Edge → Rotate Edge CW

That’s the preview - the face is NOT flat, so that’s what it looks like, just as if you bent a piece of paper in half.

Once you put a subdivision modifier on it, it’s probably a non-issue.

Indeed, your screenshot does not correspond to an extrusion of one vertex.
But that corresponds to a translation of one vertex.

So, it looks like you confused the way to extrude selection (E, yellow gizmo by default) and the way to move selection (G, RGB arrows gizmo).

You could use J to join the corner verts to the top one, you have to do it for all the corner verts one by one.

Or instead of just lifting one vert, extrude the connecting faces and then M to merge at center