UE4 - Applying Invisible materials to some bodyparts, improve FPS?

[DraxFX]

Hi, I have a human realistic character with 70,000 polys, plus cloth is almost 90,000, plus hair no idea… I thought this was too much but i tested Paragon characters… and some have the same amount of polys, Wrait is 67,000 polys.

Since in my character, cloth areas hide some bodyparts, chest, legs, etc… and for those areas i will also apply transparent materials, is it that my 90,000 polys is now only a 35,000 for unreal? even without cloth, ¿Does hiding body parts and making them transparent, reduces Unreal computing or FPS impact? or is still going to be impacted by animation?.. i won´t remove body parts, just hide them with invisible materials to change cloth styles in-game.

LOL i know a new system is coming for UE5, to allow hudge meshes… but that wont work for rigged meshes do, just static.

[Jared_Therriault]

Applying a transparent material to a mesh will not make it render faster. The opposite, in fact, there is a cost to translucency and masking. The vertices are still there, just deferring to render specific parts of the material.

If your player’s armor isn’t all one big mesh, you can set the ‘visible’ checkbox to off or ‘hidden in game’ to on in the details panel. This will not render them at all and save you some frames.

Alternatively, you can use the LOD generator in persona to create new LODs that can look just as good as the full resolution mesh, then set the minimum LOD parameter to exclude the higher resolution mesh or delete it altogether.

You could also retopologize these meshes in your 3D package of choice and reimport them, but if you’re like me you don’t want to go through that nightmare

You should look into profiling if you’re having performance issues. 70k polys isn’t that much for a main character these days, but could be an issue for having many characters onscreen (in which case, look into LODs). Try entering into the console ‘stat unit’ to get an idea of where the bottleneck might be, Game or GPU. Then enter ‘stat game’ or ‘stat gpu’ to try to ascertain the specific calls that are slowing you down.

Finally, if you need to drill down further, record a file for the session frontend using ‘stat startfile’ and ‘stat stopfile’ after you have a few seconds of performance issues recorded.