how does the grenade launcher bullet network work?

[mickey]

Hi

Can anyone discuss to me what happens when a player fires a grenade launcher?

Does the flow looks someting like:

1. client tag each bullet with an id and immediately sends network message that he has just fired
2. server receives fire message from client, adds it to a master list of bullets
3. every 50 ms server broadcasts all bullet positions, and resolves any collisions (with players and geometry)
4. each client receives updated bullet positions from server and renders them correctly. If the grenade hits or its timer has expired, it explodes. all of these info came from the server.

And if someone knows where all the network code is in the source please do point it out.

Thanks.

[divVerent]

For 2.4.2 this is true, except that the client just sends an input message (button pressed), and the server generates the ID (entity number).

In 2.4.2:

1. client sets a button flag to 1 and sends an input packet
2. server sends a network message of the grenade's creation (with an ID)
3. server calculates the grenade position every 50ms, and sends it to the client
4. finally, server sends a destroy message for the grenade to the client, and sends a particle effect and a sound message to the client too

In 2.5, it is:

1. client sets a button flag to 1 and sends an input packet
2. server sends a network message of the grenade's creation (with an ID)
3. server calculates the grenade position every 50ms, but does not send it (unless it's influenced by e.g. a jumppad)
4. client calculates the grenade position every render frame, and shows it
5. finally, server sends a destroy message for the grenade to the client, and sends a damage message to the client too, which the client will use to draw the explosion

So the difference is:

- In 2.5, the position isn't resent each frame.
- In 2.5, the sound and particle effect are in one message

[mand1nga]

The networking code resides on the Darkplaces engine and the logic is spread on the Nexuiz client and server layers which of course are run on top of Darkplaces.

See the following references:

http://ouns.nexuizninjaz.com/dev:repos

http://ouns.nexuizninjaz.com/dev:progra ... troduction

[mickey]

5. finally, server sends a destroy message for the grenade to the client, and sends a damage message to the client too, which the client will use to draw the explosion

thanks for the response guys. Does #5 also mean that calculating if a player has been hit is also done in the server and sends the clients if someone is hit?

How about collision with the geometry? I think this can be done by each of the clients - ie, no network message needs to be sent here.

[divVerent]

Collision with geometry is partially detected by the client (for bouncing, or stopping at the end of the shot). But the exact point is calculated by the server, just as well as whether someone is hit, to prevent cheating by using a manipulated client.