Build Version: 4.8.1-2591939
Description: Navigation mesh gets fully rebuilt as soon as the game is played, causing a huge fps drop on a big map with a large nav mesh. With “Runtime Generation” set to “Dynamic”.
- Make a large level with a very large nav mesh
- project settings-> nav mesh → runtime generation → dynamic
- Reload the editor, and make sure the “building navigation” message lasts at least 10 seconds
- construct a reasonably complex scene that takes the fps below max on your machine
A 20-40 fps drop just after begin play until the nav mesh is fully built. Instead I was hoping the engine could use the initial state of the pre-built nav mesh (like the Static option) and then continue working like Dynamic after that. As opposed to having to rebuild the mesh from scratch.
This issue seems to be the exact same as one found a while ago in 4.5: https://answers.unrealengine.com/questions/118670/45-navigation-mesh-rebuild-at-runtime-causing-20fp.html
I’ve also tried using the new option “Dynamic Modifiers Only” on “Runtime Generation”. But wasn’t able to get any navigation working at all. Same issue as this unanswered thread: https://answers.unrealengine.com/questions/246236/navigation-fail-with-dynamic-modifiers-only.html
I read the description of “Dynamic Modifiers Only” in: https://docs.unrealengine.com/latest/INT/Support/Builds/ReleaseNotes/2015/4_8/index.html That’s all the documentation I could find on it. And it sounds like it’s supposed to work exactly like the “Static” option when there are no nav modifiers in the map. But in practice it doesn’t work this way and I can’t figure out how to use it.