Sync Sprite renderer's flip with unet

Question

I am very new to Unity. I am working on a simple multiplayer game.

Problem I am facing is I am not able to sync the sprite renderer's flip state when we press left and right arrow keys.

Below is the code I tried.

[SerializeField] 
private SpriteRenderer spriteRenderer;

[Command]
void CmdProvideFlipStateToServer(bool state)
{
    spriteRenderer.flipX = state;
}

[ClientRpc]
void RpcSendFlipState(bool state)
{
    CmdProvideFlipStateToServer(state);
}

private void Flip()
{
    facingRight = !facingRight;
    if(isClient){
        spriteRenderer.flipX = !facingRight;
    }
    if(isLocalPlayer){
        RpcSendFlipState(spriteRenderer.flipX);
    }
}

Answer 1

I'm assuming what you want is:

In any moment the function Flip() is called on a Client.

=> his local Sprite is changed and you want to synchronize this over a server to the other clients.

---

If this is the case you re using Command and ClientRpc the wrong way:

• Command: is invoked on the Client but only executed on the Server
• ClientRpc: is invoked on the Server but only executed on (ALL) clients

=> your script should rather look somehow like

[SerializeField] 
private SpriteRenderer spriteRenderer;

// invoked by clients but executed on the server only
[Command]
void CmdProvideFlipStateToServer(bool state)
{
    // make the change local on the server
    spriteRenderer.flipX = state;

    // forward the change also to all clients
    RpcSendFlipState(state)
}

// invoked by the server only but executed on ALL clients
[ClientRpc]
void RpcSendFlipState(bool state)
{
    // skip this function on the LocalPlayer 
    // because he is the one who originally invoked this
    if(isLocalPlayer) return;

    //make the change local on all clients
    spriteRenderer.flipX = state;
}

// Client makes sure this function is only executed on clients
// If called on the server it will throw an warning
// https://docs.unity3d.com/ScriptReference/Networking.ClientAttribute.html
[Client]
private void Flip()
{
    //Only go on for the LocalPlayer
    if(!isLocalPlayer) return;

    // make the change local on this client
    facingRight = !facingRight;
    spriteRenderer.flipX = !facingRight;

    // invoke the change on the Server as you already named the function
    CmdProvideFlipStateToServer(spriteRenderer.flipX);
}