Bench Windows Terminal with a wall of 24-bits RGB ANSI scrolling chars

BenchWindowsTerminal.cs

// Bench Windows Terminal with a wall of 24-bits RGB ANSI scrolling chars
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Text;

var width = Console.WindowWidth;
var height = Console.WindowHeight;
var total = width * height;

if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
    WindowsHelper.EnableAnsiEscapeOnWindows();
}

var builder = new StringBuilder();

var totalMilli = 0.0;

// Enforce utf8
Console.OutputEncoding = Encoding.UTF8;

// Use the stream for rendering utf8 directly
var stream = Console.OpenStandardOutput();

Console.CursorVisible = false;

// Switch to alternate screen for the benchmark
Console.Out.Write("\x1b[?1049h");
Console.Out.Flush();

var clock = Stopwatch.StartNew();
const int count = 1000;
int i = 0;
for (i = 0; i < count; i++)
{

    builder.Length = 0;
    // Set cursor position 0,0
    builder.Append($"\x1b[0;0H");
    {
        for (int c = 0; c < total; c++)
        {
            var r = (byte)(c + i);
            var g = (byte)(r * 2);
            var b = (byte)(r * 4);
            var color = $"\x1b[38;2;{r};{g};{b}m";
            var o = (char)(' ' + 1 + (r  % ('z' - ' ')));
            builder.Append(color);
            builder.Append(o);
        }
        var reset = "\x1b[0m";
        builder.Append(reset);
    }
    var buffer = builder.ToString().ToCharArray();
    var utf8Buffer = Encoding.UTF8.GetBytes(buffer);

    clock.Restart();
    stream.Write(utf8Buffer);
    stream.Flush();
    clock.Stop();
    totalMilli += clock.Elapsed.TotalMilliseconds;
    Console.Title = $"[{i + 1}/{count}] Width x Height = {width}x{height} = {total}, Elapsed: {totalMilli / (i + 1)}ms";

    if (Console.KeyAvailable)
    {
        break;
    }
}
// Switch back to main screen
Console.Out.Write("\x1b[?1049l");
Console.Out.Flush();
Console.ResetColor();
Console.CursorVisible = true;
Console.WriteLine($"{width}x{height} = {total} Elapsed: {totalMilli / (i + 1)}ms");

internal static class WindowsHelper
{
    private const int STD_OUTPUT_HANDLE = -11;
    private const uint ENABLE_VIRTUAL_TERMINAL_PROCESSING = 0x0004;

    public static void EnableAnsiEscapeOnWindows()
    {
        var iStdOut = GetStdHandle(STD_OUTPUT_HANDLE);
        if (iStdOut != IntPtr.Zero && GetConsoleMode(iStdOut, out uint outConsoleMode))
        {
            SetConsoleMode(iStdOut, outConsoleMode | ENABLE_VIRTUAL_TERMINAL_PROCESSING);
        }
    }

    [DllImport("kernel32")]
    private static extern bool GetConsoleMode(IntPtr hConsoleHandle, out uint lpMode);

    [DllImport("kernel32")]
    private static extern bool SetConsoleMode(IntPtr hConsoleHandle, uint dwMode);

    [DllImport("kernel32")]
    private static extern IntPtr GetStdHandle(int nStdHandle);
}