Blender Bug total mistery

flavie404

(Hello, i have a problem with my meshes they suddenly appear to have weird bug with normal only when i move my camera on axis like front or side and i can't use a knife tool normaly it just rip off the face completely in all case and i tested a new file it work fine here,and my normal are correctly calculated.

All my mesh are hand made and i use a rigify workflow to animate for unreal, i made this work for a moment now and it probably work but not being able to use the knife tool is a pain

I have realy no idea but maybe its cause i m using the steam version of blender that keep up to date the software and maybe my mesh didnt liked it but i suspect a lot more something else

i also tried to check with the 3d print addon see if there is some weird thing going on but there is no problem, also it was working fine before i think its when i parented my mesh to my rig but i dont understand)

**Edit 4 : I just changed my layout to see the file and test thing and in this form everything work properly this is realy weird its the same files**

What drive this problem then i can't isolate it

To Resume current status :

When im in the first layout of my blend file everything work perfectly, i can knife tool anything and there is no problem of normal anywhere but the second i change the layout (shown in those screenshot under) those problem appear


**This thing on the upper screenshot doesnt occur as stated upper when im not picking a side with the camera but i actualy can't knife tool and my mesh have weird behaviour with face etc.. except when i m in the the first layout of my blend file where everything work properly**

okidoki

to check the normals first .. Well..to be able to have a look at this problem you might want to restrict your model to a special part and then publish the blend file ?? So some might find any problematic setting.. somtimes it's just the graphic driver on some systems while on others there is everything okay..
In the WTF-image it looks like vieport culling.. but then the normals seem to be okay..  this thing with the hidden face alsmost look like some wrong clipping value.. but then this would show up also in *Object* mode.. ohh hidden.. there are no hidden faces in *Edit* mode (you know..reveal with Alt-H) ??

Ruz

have you checked the viewport clipping? also try disabling camera culling or clipping region and for each object apply all transforms
Thats all  can think of right now, though i am sure I have had this issue in the past

Also check the meshes normals, go to the overlays and check 'face orientation'

go to mesh, normals 'recaluculate outside'  if necessary

Tiles

I seem to remember that i have seen this once before. It was the corner normals that were troubled and were pointing into different directions like the faces would have split edges. In this case Recalculate Normals doesn't help, since they already points outwards. Try Set from Faces. It's in the same menu than Recalculate Normals. Edit Mode, Mesh menu, Normals sub menu.
And to see the corner normals, go to the Viewport Overlays.