Please help with this rendering issue

Please can people advise me as to what is happening in my UE4 level. This is my first time using UE4 and so I do not know how to stop this. It only occurs in this localised area of the level, and persists through restarts and rebuilds.
Thank you

Since it is a BSP, rebuilding geometry might help. In the bug2.png file, is that also a BSP or a static mesh? If you do not have tris on the back side of the mesh, they will not render. One way to fix it is to add the tris in the modelling software, the other is to check ‘Use as Two Sided Material’ in the material that the mesh uses.

One could make an effect like that on purpose but I don’t suppose you did.

The wooden structures are a grouping of BSP. I will attempt a geometry rebuild and see if that fixes it.

Well it looks like you have some normals flipped. Have you checked to make sure all faces are point outward?

Hey Doomspell42,

It sounds like you are a bit new to game development as well, as ‘Tris’ is a common term in the game design community that refers to ‘Triangles’. Your tris and polys are the total count of triangles and polygons of the relative mesh.

I suggest taking a look at our documentation on Rendering and Graphics to familiarize yourself with the terminology, and some of the basics required for understanding game development within UE4.

Rendering and Graphics

UE4 Terminology

These should get you started on the right path to designing your game or project!


Rebuilding the geometry of the level did not solve the issue. I’m afraid I do not understand the term Tris, probably being new to the program. Selecting twin sided on the material also did not solve the problem. Below is a further screen shot showing the BSP structure highlighted using the Geometry tool.

As you can see below, I have simply duplicated the same group of BSP’s over and over to form the wooden walk way. The previous group was fine, as shown below. No settings have been changed. Also, UE4 bug.png was created with a default box BSP and was fine when moved out of the vicinity of that area of the level.

Thanks, i’ll take a look at these and see if i can find a solution in program.

Problem sorted, I converted the BSP group into a Static mesh. Thank you for the help :slight_smile: