RobustToolbox/Robust.Client/GameStates/NetGraphOverlay.cs

using System.Collections.Generic;
using Robust.Client.Graphics;
using Robust.Client.Graphics.Drawing;
using Robust.Client.Graphics.Overlays;
using Robust.Client.Interfaces.Console;
using Robust.Client.Interfaces.GameStates;
using Robust.Client.Interfaces.Graphics.Overlays;
using Robust.Client.Interfaces.ResourceManagement;
using Robust.Client.ResourceManagement;
using Robust.Shared.Interfaces.Network;
using Robust.Shared.Interfaces.Timing;
using Robust.Shared.IoC;
using Robust.Shared.Maths;
using Robust.Shared.Timing;

namespace Robust.Client.GameStates
{
    /// <summary>
    ///     Visual debug overlay for the network diagnostic graph.
    /// </summary>
    internal class NetGraphOverlay : Overlay
    {
        [Dependency] private readonly IGameTiming _gameTiming = default!;
        [Dependency] private readonly IClientNetManager _netManager = default!;
        [Dependency] private readonly IClientGameStateManager _gameStateManager = default!;

        private const int HistorySize = 60 * 3; // number of ticks to keep in history.
        private const int TargetPayloadBps = 56000 / 8; // Target Payload size in Bytes per second. A mind-numbing fifty-six thousand bits per second, who would ever need more?
        private const int MidrangePayloadBps = 33600 / 8; // mid-range line
        private const int BytesPerPixel = 2; // If you are running the game on a DSL connection, you can scale the graph to fit your absurd bandwidth.
        private const int LowerGraphOffset = 100; // Offset on the Y axis in pixels of the lower lag/interp graph.
        private const int MsPerPixel = 4; // Latency Milliseconds per pixel, for scaling the graph.

        /// <inheritdoc />
        public override OverlaySpace Space => OverlaySpace.ScreenSpace;

        private readonly Font _font;
        private int _warningPayloadSize;
        private int _midrangePayloadSize;

        private readonly List<(GameTick Tick, int Payload, int lag, int interp)> _history = new List<(GameTick Tick, int Payload, int lag, int interp)>(HistorySize+10);

        public NetGraphOverlay() : base(nameof(NetGraphOverlay))
        {
            IoCManager.InjectDependencies(this);
            var cache = IoCManager.Resolve<IResourceCache>();
            _font = new VectorFont(cache.GetResource<FontResource>("/Textures/Interface/Nano/NotoSans/NotoSans-Regular.ttf"), 10);

            _gameStateManager.GameStateApplied += HandleGameStateApplied;
        }

        private void HandleGameStateApplied(GameStateAppliedArgs args)
        {
            var toSeq = args.AppliedState.ToSequence;
            var sz = args.AppliedState.PayloadSize;

            // calc payload size
            _warningPayloadSize = TargetPayloadBps / _gameTiming.TickRate;
            _midrangePayloadSize = MidrangePayloadBps / _gameTiming.TickRate;

            // calc lag
            var lag = _netManager.ServerChannel!.Ping;

            // calc interp info
            var interpBuff = _gameStateManager.CurrentBufferSize - _gameStateManager.MinBufferSize;

            _history.Add((toSeq, sz, lag, interpBuff));
        }

        /// <inheritdoc />
        protected internal override void FrameUpdate(FrameEventArgs args)
        {
            base.FrameUpdate(args);

            var over = _history.Count - HistorySize;
            if (over > 0)
            {
                _history.RemoveRange(0, over);
            }
        }

        protected override void Draw(DrawingHandleBase handle)
        {
            // remember, 0,0 is top left of ui with +X right and +Y down

            var leftMargin = 300;
            var width = HistorySize;
            var height = 500;

            // bottom payload line
            handle.DrawLine(new Vector2(leftMargin, height), new Vector2(leftMargin + width, height), Color.DarkGray.WithAlpha(0.8f));

            // bottom lag line
            handle.DrawLine(new Vector2(leftMargin, height + LowerGraphOffset), new Vector2(leftMargin + width, height + LowerGraphOffset), Color.DarkGray.WithAlpha(0.8f));

            int lastLagY = -1;
            int lastLagMs = -1;
            // data points
            for (var i = 0; i < _history.Count; i++)
            {
                var state = _history[i];

                // draw the payload size
                var xOff = leftMargin + i;
                var yoff = height - state.Payload / BytesPerPixel;
                handle.DrawLine(new Vector2(xOff, height), new Vector2(xOff, yoff), Color.LightGreen.WithAlpha(0.8f));

                // second tick marks
                if (state.Tick.Value % _gameTiming.TickRate == 0)
                {
                    handle.DrawLine(new Vector2(xOff, height), new Vector2(xOff, height+2), Color.LightGray);
                }

                // lag data
                var lagYoff = height + LowerGraphOffset - state.lag / MsPerPixel;
                lastLagY = lagYoff - 1;
                lastLagMs = state.lag;
                handle.DrawLine(new Vector2(xOff, lagYoff - 2), new Vector2(xOff, lagYoff - 1), Color.Blue.WithAlpha(0.8f));

                // interp data
                Color interpColor;
                if(state.interp < 0)
                    interpColor = Color.Red;
                else if(state.interp < _gameStateManager.TargetBufferSize - _gameStateManager.MinBufferSize)
                    interpColor = Color.Yellow;
                else
                    interpColor = Color.Green;

                handle.DrawLine(new Vector2(xOff, height + LowerGraphOffset), new Vector2(xOff, height + LowerGraphOffset + state.interp * 6), interpColor.WithAlpha(0.8f));
            }

            // top payload warning line
            var warnYoff = height - _warningPayloadSize / BytesPerPixel;
            handle.DrawLine(new Vector2(leftMargin, warnYoff), new Vector2(leftMargin + width, warnYoff), Color.DarkGray.WithAlpha(0.8f));

            // mid payload line
            var midYoff = height - _midrangePayloadSize / BytesPerPixel;
            handle.DrawLine(new Vector2(leftMargin, midYoff), new Vector2(leftMargin + width, midYoff), Color.DarkGray.WithAlpha(0.8f));

            // payload text
            DrawString((DrawingHandleScreen)handle, _font, new Vector2(leftMargin + width, warnYoff), "56K");
            DrawString((DrawingHandleScreen)handle, _font, new Vector2(leftMargin + width, midYoff), "33.6K");

            // interp text info
            if(lastLagY != -1)
                DrawString((DrawingHandleScreen)handle, _font, new Vector2(leftMargin + width, lastLagY), $"{lastLagMs.ToString()}ms");

            DrawString((DrawingHandleScreen)handle, _font, new Vector2(leftMargin, height + LowerGraphOffset), $"{_gameStateManager.CurrentBufferSize.ToString()} states");
        }

        protected override void Dispose(bool disposing)
        {
            _gameStateManager.GameStateApplied -= HandleGameStateApplied;

            base.Dispose(disposing);
        }

        private void DrawString(DrawingHandleScreen handle, Font font, Vector2 pos, string str)
        {
            var baseLine = new Vector2(pos.X, font.GetAscent(1) + pos.Y);

            foreach (var chr in str)
            {
                var advance = font.DrawChar(handle, chr, baseLine, 1, Color.White);
                baseLine += new Vector2(advance, 0);
            }
        }

        private class NetShowGraphCommand : IConsoleCommand
        {
            public string Command => "net_graph";
            public string Help => "net_graph <0|1>";
            public string Description => "Toggles the net statistics pannel.";

            public bool Execute(IDebugConsole console, params string[] args)
            {
                if (args.Length != 1)
                {
                    console.AddLine("Invalid argument amount. Expected 2 arguments.", Color.Red);
                    return false;
                }

                if (!byte.TryParse(args[0], out var iValue))
                {
                    console.AddLine("Invalid argument: Needs to be 0 or 1.");
                    return false;
                }

                var bValue = iValue > 0;
                var overlayMan = IoCManager.Resolve<IOverlayManager>();

                if(bValue && !overlayMan.HasOverlay(nameof(NetGraphOverlay)))
                {
                    overlayMan.AddOverlay(new NetGraphOverlay());
                    console.AddLine("Enabled network overlay.");
                }
                else if(overlayMan.HasOverlay(nameof(NetGraphOverlay)))
                {
                    overlayMan.RemoveOverlay(nameof(NetGraphOverlay));
                    console.AddLine("Disabled network overlay.");
                }

                return false;
            }
        }
    }
}