Texture sample/sample parameter

Unless you need some specific tiling/wrap/clamp/mirror combination, it's generally best to set all the texture sample/texture sample parameter nodes to “Shared: Wrap” This can give some sliiiight benefit on some AMD hardware. It can also help with decreasing some texture lookups.

 

 “Citation would be derived from one of AMD guides(~2015) for specific architecture as well as post of someone from Epic. It might/ might not apply to modern AMD cards.

The gist revolves in ALU being involved in fetching descriptors. It is not something one should bother with much on material editor level though.” - Deathrey

 

 

 

Textures (and their settings)

Compression settings

 

Default compression

should generally beused for albedo textures.

 

Normal map Compression

Should always be used for normal maps.

In almost no cases is it worth it to pack another texture in the blue channel and using some material nodes to append the Red/Green channel of a normal texture.

The Normal compression --under the hood-- Puts the Red channel of a normal map in the combined RGB channels, and the Green channel in the Alpha channel (which is basically a combined RGB channel to begin with), and generates the blue channel through magic code.

So unless a very specific situation, compress normal maps as normal maps please.

Normal map compression also means that each level of mipmap chain, that is generated for your texture by the engine, will be re-normalized.

This limits the possibility of storing anything other than an actual normal map using this compression setting.

 

 

Masks/Grayscale Compression

Useless, only disables “SRGB” in that case if you have a RGB packed texture just keep it at the “Default” setting and disable SRGB yourself. Saves you some error/warning head-aches when applying other textures in a material instance as the “Texture Samples” do not really like using different compression settings than their originally applied texture.

Use Alpha compression if your texture is a grayscale texture.

 

Alpha Compression

In my humble opinion, a highly undervalued compression setting.

It desaturates an RGB texture and puts it into the Alpha channel, removing the RGB channel.

If your texture is already a grayscale texture it simply puts it into the alpha channel.

Since the Alpha channel is basically an RGB channel in itself, it has the same amount of bits of RGB combined which results in much crisper albeit grayscale textures, so crisp in fact you often can get away with using smaller resolutions (saving resource size).

Additionally, it does not have any of the compression artifacts one can expect from the RGB channel packing compression algorithm.

 

Other compression settings.

All I can say is, use them accordingly. I myself do not use these as much (besides the vertex displacement one for vertex animation) so I cannot give extensive information about these settings.

 

Additional Texture settings

 

Compress without Alpha

If you accidentally imported your texture with an alpha channel, either go back and fix your mistake, or turn this on so the alpha gets removed, saving some resource size.
Keep in mind that the alpha channel-having version is still stored in the uasset, so you might want to go back to your authoring software and remove the alpha channel.

 

 

Compression Quality

I tend to not touch this as it's a “on a per situation” usage situation.
Increase the compression if the texture still looks good I guess, saving some resource size.

 

Texture Group

Very important to set this up properly! DO NOT FORGET!

Imagine you are playing a new highly anticipated game but you know your pc is not up to snuff to run this new game at the highest/ultra settings so you cherry pick through some graphical options.

Let's set world resolution (content related to the group “world”) to high.

Now, let's set “character detail” to Ultra because you want to see the hero in all its glory!

And finally, “Effects” will be set to medium, because who cares about sparkles right?!

If the artist did the job, lowering the “Effects” settings to medium would result in all textures potentially reducing in quality. (Lower texture resolution trough changing mipmap levels, and depending on how its set up, changing LOD levels to reduce polycounts)

If the artist forgot about this though, lowering the “Effects” settings to medium did nothing, as all the content it should affect still uses the “World” texture group.

Imagine how it feels if you play a game, you lower a certain graphic setting and the game still runs like poop… Right! That's why it's important to set this up right!

 

SRGB

Easy, if it's not albedo, generally turn this off.