I’ve actually noticed this throughout previous versions. When UE4 is asked to render a lot on screen, doesn’t seem to matter what, the frame rate drops by sometimes, a whopping 20 frames. The drop only lasts about millisecond, but sometimes (on rare occurrences) the editor will hang for slightly longer than a second. I’ve tesed this in both my own levels and the examples provided by epic (those with a lot on screen I:E particle effects)
I:E I’ll be running a tilled landscape at a solid 38 FPS then when I release the Right mouse button and the frame drops, just quick enough for the fps reader to read it.
This isn’t a big bug, and honestly it doesn’t bother me to much. But just thought you guys would want to know.