AI Shaky Movement On Slopes On The Client Side

[YuchenMei]

Hi, everyone,

I am trying to fix an issue where the AI shakes when walking up/down slopes (looking good on flat grounds). I think it dues to different movement modes on the server side and the client side because I can see on the server side, the AI is using MOVE_NavWalking but on the client side, it is using MOVE_Walking. (The navmesh only exists on the server side).

So when the navmesh is very different from the mesh collision (on slopes), the client-side prediction will be very different from the actual movement on the server side, then the server will correct the client which causes the jerky movement.

I changed the default movement on the server side to MOVE_Walking then the shake stops because both the server and the client are now using the same movement mode. But that’s not a good fix apparently. (MOVE_Walking is too expensive).

Any ideas what I can do to make the client AI movement prediction use MOVE_NavWalking so it matches the server movement mode (I am not sure whether it’s doable because there is no navmesh on the client side…) or anything I can do to get rid of the shaky movement on slopes on the client side?

Thanks in advance for any answers!

[JasonCoutee]

You can correct this a bit with client side navigation in project settings. The issue then seems to be that the clients will then see the ai as “is falling” if spawned by authority vs placed in the level. The pathfinding and walking mode will however be navmesh walking on both clients and server at this point. I currently have a UDN ticket checking on the isfalling client issues when authority spawned