Why is my Cubemap getting resized when imported?


I have a cubemap that I am using for a space sky sphere, I have created the cube map following the instructions set out in the docs, everything goes fine and the texture maps to the mesh correctly however, the texture is modified by the importer which changes the scaling which leads to a blurred texture I guess because the pixels are re sampled and stretched.

What should I be doing here to avoid the blurring? I’ve tried with textures of varying sizes so 512 x 512, 1024 x 1024 (6 images of each for each axis) but its always the same blurry image after importing as the image looks fine in Photoshop.

Would appreciate any suggestions,


It sounds like this passage from the docs is what is happening:

“The cubemap used for ambient lighting. The texture should be created by importing a .hdr image in the longitude/latitude sphere unwrapping format. The engine automatically precomputes blurry versions of the texture and stores the result in one cubemap texture. The lower resolution mips of the texture store the diffuse preconvolved version of the HDR environment.”


How do I avoid this?

Hi Maddius -

You will want to open the Texture in the Engine and change the Mip Gen Settings under Level of Detail. You can try a few but one of the Sharpen ones should fix up the blurry problem you are getting.

Thank You

Eric Ketchum

Thanks for the reply however,

Looks like this (How to implement a standard cubemapped skybox? - Pipeline & Plugins - Unreal Engine Forums) thread has the answer which is pretty much what I expected, all images are down sampled to 512 which causes the blur.

UE4 seems to be geared towards procedural skies.


You just can set Mip Gen Settings to NoMipmaps

Setting Mip Gen Settings to NoMipmaps doesn’t work for me. My HDR is locked at 512x512x6 despite this setting change.

I’ve tried to change the maximumtexture size to 2048