How to fix fps drops in my map?

Development Rendering
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1

I’m in edit mode, making a realistic looking map with a lot of vfx spawners that use niagara fire from ue5. When looking away from the center of my map it’s 60fps, but when just looking towards the center it drops to 20-30fps and running through the middle can give you 15-30 fps while on the edges 60fps. It’s a pretty center heavy map with a main building in the middle. I think it could be the abundance of fire vfx but not sure how to actually fix it without deleting too many vfx spawners.

Is there a practical way to maintain a 60fps throughout the whole map? or atleast reduce the center fps drops?

2

First step is to see what is causing the drops, try turning all the vfx spawners off to see if they are the culprit. If not you have more searching to do, but if they are you’ll simply have to get rid of some. Maybe try making your own fire particles that are cheaper than the built in ones. Set the emitters to run on the gpu as it can usually handle more particles, and optimize the particles so you can have as many as you want while maintaining good performance. You may have to sacrifice some realism for performance but optimization is a crucial part of game development to learn and sacrifices always have to be made

3

did some testing and seems they are not the culprit, it’s actually the point and spot lights. There are only about 25 of them and they aren’t set to moveable, although in a relatively small space, maybe 15 in the main building. Surely some lights shouldn’t drop fps this bad? Hasn’t happened to me before. Anything I can do?

4

Hello,

Try disabling ‘Cast Shadows’ on those lights.

5

one thing I don’t understand is I have another map that has far more lights than this one, all with cast shadows and it’s a steady 60 fps on everything. This new one for some reason, the lights cause hella lag. could it be because on this map I’m using more custom assets and materials and the lights reflect on them? I’m not sure, any ideas how to fix?

6

What sort of difference in performance did you see when disabling shadow casting?

Before materials/reflections, I’d wonder about overall polycount. If you look at these custom assets in wireframe view - do they seem reasonable? (not extremely dense)

I forget if it’s on by default or not - but if you go to Edit → Editor Preferences → Performance there is a checkbox for ‘Show Frame Rate and Memory’ - With this enabled, you might be able to troubleshoot in-editor instead of needing to launch a session every time.