about poly's in UE4

hey guys

I’m kinda new to the game design world and i really wanna learn some cool stuff about it and make some awesome game but i have one question.

how much poly’s should a full game have because everywhere i turn people are talking about if your game or character have to much poly’s your game will not
have the best look or run what about a game like cod2, arma3, gta5, they look pretty to me and how they get them to look so dam good if they have to worried about polygon and can i create a map like battlefield 4 in ue4 thanks for all the tips and help

Poly Count → always depends on the game, the map size and style. I would recommend you to take a look at some character modelling tutorials for game development → normally you create a high poly mesh - bake the normal map,… - simplify the mesh
I always try to stay as low as possible :slight_smile:

Yes, you can make every kind of map in the UE4 :wink: (even with destruction ->

A full game can have as many polygons as you want really, the limitation does not apply in the sense of total poly’s per game. What you need to be concerned with is the number of poly’s being drawn on screen at any time during the game.

For characters the recommendation for the last gen titles was to keep them below 30k tri’s, this is still a good recommendation, but you can go higher than this if required.

To keep the poly count down make sure you are baking as much information onto the low poly mesh as possible, using normal maps created based on your high poly mesh to fill in the smaller details, allowing you to use less poly’s for (almost) the same result. A lot of fine detail can be added through through the material, it is not always necessary to sculpt it onto the mesh.

Basically for all meshes you create try and reduce the poly count as far as possible while still retaining the detail you need. Use LOD’s and normal maps wherever possible to add in extra detail as it is required.

You can create a map like BF4 in UE4 as well, the maximum size is actually quite a bit larger than the map in that game. The details of the map and models that populate it will need to be created, but there is no limitation that would prevent you from creating a game of that scope. It will be very difficult without a large team, but technically it is possible given enough time. :slight_smile:

On stress test, I’ve had about 11 million + polys in frustrum at any time @ 60FPS on a GTX 470. Which is our base test (min specs) machine and a stand alone build…

I’d be far more concerned with lighting / shadows and materials (especially particles) and to a lesser extent anything containing alpha. Dynamic lighting with dynamic CSM equated to a 50 %+ (roughly) drop in speed, with RT shadows around 40 - 35 % and with a couple of basic fire particles about a 10% drop although there’s some work to do on that from our end. Too many particles last time I checked cripples a scene quickly…

Post effects don’t really seem to make that much difference, fill rate with 1.28GB (GTX 470) can be problematic at times.

We have a test bench which includes around 10 variations of machines, AMD / Nvidia (Intel) and PS4 devkits. When were further on I’ll post testing results.

Keep us updated on what you find regarding the impact on FPS due to various things. This could be really important information that could help people choose the right path early on in their projects.

How do you actually get Unreal Engine 4 to display how many polys are rendered in the current frame?!?
I knew the console command for it in UE3, but in UE 4.5 the stat rhi command displays very little information and no tri count for me.

I’m also really curious how your testing will go ShadowKindGames!

I think you can access that with a console command or with the profiler (dont know exactly where ^^)

Just in case someone else was wondering how to do this. The stat rhi console command displays the triangle and drawcall count now! NOT the stat D3d11rhi as it used to be in UDK iirc. Oddly enough the stat rhi command is not even in the quoted list, I found out about it in this video: which is very relevant to this topic.

What about NPCs? how much NPCs can a map lke this handle at once on screen?

It depends on too many factors, there’s no hard numbers for that kind of thing because every game is different and every object is going to be different.

Final Fantasy 15’s on-screen poly-count is 5 million polys. But that’s 4 main characters on screen and a ton of foliage. The caveat is the game runs with some input lag and caps at 30 fps. Each of the characters is made with 100k+ polys, that includes hair cards and clothes. I would use those numbers as a limit for even simple scenes because anything below 60 fps on the machine building the project could spell disaster when it comes time for shipping.

Depending on the visual fidelity of your project, you’ll have to do some stress testing to figure out your own budget. You may find that your models can be thrown about a scene quite generously before you see a performance hit, but remember that lighting, materials, physics, and particles will also take a hefty chunk out of your budget. So you need to put together a comprehensive test scene to really know.

In the case of one of my projects, I had a very large/complicated opening scene that ran at 0.5 fps until I had removed the collisions and turned off cast shadows from animated objects that now I can never let the player get near. Also grabbing chunks of the environment and using the “merge actors” right-click menu option and crushing the triangle count and material calls for many objects. Now runs at a smooth 60 fps on a laptop with a 970m, and the post process is using a heavy depth of field and exponential height fog (and atmospheric fog) to help blur distant objects.