I'm overhauling combat, and part of that, I've cancelled all the vanilla events related to that (left click, left click on block, left click on entity, etc) and am now sending packets back and forth from server/client to determine when and how a player should attack. However, an element I'm missing server-side is the ability to get the entity currently being looked at. 

 

So when an entity is struck, the event is canceled and a packet is sent to server, to my capability class where the rest of the logic is done. I've sent over that entity's position but I've two questions:

 

1) Is raycasting based on the player's look vector unreliable server-side?

 

2) If I just do a basic AABB bound check, do you think it's too imprecise?

 

For both cases, I'm thinking of situations where an entity is flailing about, or shares similar coordinates with another mob (say, a Villager and a jumping chicken) that shares the same coordinates, but not necessarily the same boundary spaces. 

Should I be doing something else?

 

Edited May 13, 20205 yr by Turtledove

I already have a function that does line segment-plane intersections for an entity's location and height, but it's moreso for my AOE attacks, not for precise single-entity-hits.

Can't you just use Minecraft.getInstance().pointedEntity on the client and send the entity's id to the server? Be wary that if the player is not looking at an entity pointedEntity will be null.

Edited May 13, 20205 yr by kaydogz

47 minutes ago, Turtledove said:

1) Is raycasting based on the player's look vector unreliable server-side?

Yes.

Especially when there is lag, the entity under attack might already moved away from the player's look vac by the time the packet reaches the server.

You should send the entity under attack from the client to the server, and implement some sort of check to prevent cheating.

 

49 minutes ago, Turtledove said:

2) If I just do a basic AABB bound check, do you think it's too imprecise?

AFAIK AABB is precise enough for this.

Thanks all, got it resolved. I used both AABB and basic linear algebra to check for intersections.