SyncFlags.Interpolate: How Networked Property Interpolation Works — Supported Types, InterpolationBuffer, and Delay

SyncFlags.Interpolate: How Networked Property Interpolation Works

When [Sync( SyncFlags.Interpolate )] is applied to a property, proxy clients receive a smoothed value between network ticks rather than the raw snapped value.

Supported Types

Interpolation is only supported for these types:

• float


• double


• Angles


• Rotation


• Transform


• Vector3

How It Works

On proxy clients, the getter is wrapped by _syncGetValue. When SyncFlags.Interpolate is set:

1. An InterpolatedSyncVar<T> is created on first use, backed by an InterpolationBuffer<T>.
2. When a network update arrives, Update(value) adds the new value to the buffer with the current Time.NowDouble timestamp.
3. The getter queries the buffer at Time.NowDouble - Networking.InterpolationTime, returning a smoothed value.
4. Old buffer entries are culled when they are older than Networking.InterpolationTime 3.

public class MyComponent : Component
{
    // Smooth position on proxies
    [Sync( SyncFlags.Interpolate )] public Vector3 NetworkPosition { get; set; }

    // Smooth rotation on proxies
    [Sync( SyncFlags.Interpolate )] public Rotation NetworkRotation { get; set; }

    protected override void OnUpdate()
    {
        if ( IsProxy )
        {
            // NetworkPosition returns interpolated value on proxies
            WorldPosition = NetworkPosition;
        }
    }
}

Interpolation Delay

The interpolation introduces a delay of Networking.InterpolationTime seconds. This is a trade-off: smoother movement at the cost of slightly delayed position display.

Owner Behavior

On the owner, SyncFlags.Interpolate has no effect on the getter — it returns the raw value directly. Interpolation only applies on proxy clients.

Transform Interpolation vs SyncFlags.Interpolate

The GameObject transform has its own built-in interpolation system (controlled by NetworkFlags.NoInterpolation). SyncFlags.Interpolate is for custom [Sync] properties, not the transform.