How to make a character with no much polygons ? And how many polygons for a scene ?

Hey guys, i’m new here and with unreal engine 4, and before I start my project in UE4 i’d like to do all of the modeling, i’m using maya for the scene and Zbrush for the characters.
As for the scene I have been careful on the number of polygons I use for every object before I set everything up. Even if i know that with some scripts I’ll be able to delete and create some objects in game, I’d like to know how many polygons is it recommended to have on screen for a PC game ? I haven’t found any precise answer on the internet that’s why i’m here.

And for my second question, concerning the characters, I’ve read that it’s recommended to have something around 30k polygons, which seems really low.
So, how many polygons is it recommended for a character ? And if it’s really 30k, how do I make some details, with Zbrush, a character with 30k polygons looks like a silouhette with not much details, Do I have to retopologize it after ?

Thanks for the future answers !

It depends on what the needs of your game are, there’s no way to know for sure since every game is different you won’t know what the performance is like until you put everything together and start testing. At that point then you might have to make changes like lowering texture resolutions or adding level of detail to your meshes. People who have worked in games for a while have a pretty good idea how to get good detail while getting good performance, sometimes it just takes experience to be able to know how far to go.
If characters are important to your game, then you might use a higher detail for them and a lower detail for the environment, or you make the environment smaller. There’s many things that can affect performance.

To keep the details you’d need to bake the high poly mesh to get normal maps and apply those to the decimated low poly mesh.

You could also try one of the free mesh optimisation services:

https://www.simplygon.com/cloud
https://www.mixamo.com/decimator

You have zbrush, last time i seen it it had nice plugin called decimator.

You should bak normals and use them instead of millions of polys. 30k is really plenty for character.

Ok thanks, so If i understand correctly all of the details will be in the textures ?

The normal map is for small details, like wrinkles on a face. For characters it’s best to do retopology by hand, decimation does not take into account the edge flow that is required for a person to deform correctly. Zbrush has all of the tools for that.

I have about 2 million polygons in one scene, and my fps was slow to 10. I use exponential heigh fog, and for detail models i use 3 LODs and fps is still go down. I have good pc, games like Far Cry 4 run in Ultra graphic, and Witcher 3 Very High. So anyone have a information, how many polygons in open world have game like witcher, far cry, uncharted etc?

2-10 million seems about normal for a modern AAA game http://polycount.com/discussion/141061/polycounts-in-next-gen-games-thread

You should take into account other factors: Texture resolution and Mip Gen Setting, Shaders, Particles, Post Process Effects can also eat up some of you frames. Normally, I pay attention to any change in FPS when I make some changes to my scene. It helps me to debug any problem before there are too many things are placed in my scenes.

So if i have many textures 4096px with no compression [PNG oryginal format RGBA], that is really weight for GPU and/or CPU? I think, it only need much RAM. If i resize textures to 2048px or compressed to 50%, my efficiency go up? I need advice UE programmer.

Modeling for games involves a lot of retopology techniques;
And retopo/baking is a science/job at itself, it’s like remaking the same model again and again and again… most artists hate it.