totte/Program.cs

using OpenTK.Graphics.OpenGL4;
using OpenTK.Mathematics;
using OpenTK.Windowing.Common;
using OpenTK.Windowing.Common.Input;
using OpenTK.Windowing.Desktop;
using OpenTK.Windowing.GraphicsLibraryFramework;
// https://docs.sixlabors.com/api/ImageSharp/SixLabors.ImageSharp.Image.html
using Image = SixLabors.ImageSharp.Image;
using SixLabors.Fonts;
using SixLabors.ImageSharp.Metadata.Profiles.Exif;
using SixLabors.ImageSharp.Metadata.Profiles.Xmp;
using SixLabors.ImageSharp.Drawing.Processing;
using SixLabors.ImageSharp.Drawing;
using SixLabors.ImageSharp.Formats.Jpeg;
using System;
using System.Diagnostics;
using System.Runtime.CompilerServices;
using System.Text;
using System.Xml.Linq;

namespace SemiColinGames;

public class FpsCounter {
  private readonly int[] frameTimes = new int[30];
  private double fps = 0;
  private int idx = 0;

  public int Fps {
    get => (int) Math.Ceiling(fps);
  }

  public void Update() {
    var now = Environment.TickCount;  // ms
    if (frameTimes[idx] != 0) {
      var timeElapsed = now - frameTimes[idx];
      fps = 1000.0 * frameTimes.Length / timeElapsed;
    }
    frameTimes[idx] = now;
    idx = (idx + 1) % frameTimes.Length;
  }
}

public class CameraInfo {
  public readonly Vector2i Resolution;

  private CameraInfo(Vector2i resolution) {
    Resolution = resolution;
  }

  public static readonly CameraInfo NIKON_D7000 = new(new Vector2i(4928, 3264));
  public static readonly CameraInfo CANON_EOS_R6M2 = new(new Vector2i(6000, 4000));
  public static readonly CameraInfo IPHONE_12_MINI = new(new Vector2i(4032, 3024));
}

public enum ToolState {
  Active,
  Done,
  Canceled
}

public interface ITool {
  void SetActivePhoto(Photo photo);
  ToolState HandleInput(UiGeometry geometry, KeyboardState input, MouseState mouse, Game game);
  string Status();
  void Draw(UiGeometry geometry, Game game);
}

public class ViewTool : ITool {
  Photo? activePhoto;

  public void SetActivePhoto(Photo photo) {
    activePhoto = photo;
  }

  public ToolState HandleInput(UiGeometry geometry, KeyboardState input, MouseState mouse, Game game) {
    return ToolState.Active;
  }

  public string Status() {
    return "";
  }

  public void Draw(UiGeometry geometry, Game game) {
  }
}


// FIXME: remove unneeded dependencies on "Game" or at least refactor them a bit.
public class CropTool : ITool {

  Photo activePhoto;
  Vector2i mouseDragStart;
  Vector2i mouseDragEnd;
  string status = "";

  public CropTool(Photo photo) {
    activePhoto = photo;
  }

  public void SetActivePhoto(Photo photo) {
    if (photo != activePhoto) {
      // FIXME: handle this sensibly.
    }
    activePhoto = photo;
  }

  public ToolState HandleInput(UiGeometry geometry, KeyboardState input, MouseState mouse, Game game) {
    Vector2i mousePosition = (Vector2i) mouse.Position;

    if (mouse.IsButtonPressed(MouseButton.Button1)) {
      if (geometry.PhotoBox.ContainsInclusive(mousePosition)) {
        mouseDragStart = mousePosition;
      }
    }

    if (mouse.IsButtonDown(MouseButton.Button1)) {
      if (geometry.PhotoBox.ContainsInclusive(mousePosition)) {
        // FIXME: really this should be clipped to the active photo's drawable area, not the whole photobox.
        mouseDragEnd = mousePosition;
      }
    }

    Vector2i start = game.ScreenToImage(mouseDragStart);
    // FIXME: this needs to be the actual width of the computed box.
    Vector2i size = game.ScreenToImage(mouseDragEnd) - start;

    status = $"({start.X}, {start.Y}) {size.X}x{size.Y}";

    if (input.IsKeyPressed(Keys.Enter)) {
      ApplyCrop(game);
      return ToolState.Done;
    }

    if (input.IsKeyPressed(Keys.Escape)) {
      activePhoto.CropRectangle = Rectangle.Empty;
      return ToolState.Canceled;
    }

    return ToolState.Active;
  }

  // left, right, top, bottom
  (int, int, int, int) GetCrop() {
    // FIXME: this expects the start point in the top left and the end point
    // in the bottom right; some sign flipping needs to occur to make anchors
    // in other direction work well.
    Vector2i start = mouseDragStart;
    Vector2i end = mouseDragEnd;
    // FIXME: choose the aspect ratio based on the original image aspect ratio.
    // FIXME: allow for unconstrained crop, 1:1, etc.
    end.Y = Math.Min(end.Y, start.Y + (end.X - start.X) * 4 / 6);
    end.X = start.X + (end.Y - start.Y) * 6 / 4;
    int left = Math.Min(start.X, end.X);
    int right = Math.Max(start.X, end.X);
    int top = Math.Min(start.Y, end.Y);
    int bottom = Math.Max(start.Y, end.Y);
    return (left, right, top, bottom);
  }

  void ApplyCrop(Game game) {
    var (left, right, top, bottom) = GetCrop();
    int area = (right - left) * (bottom - top);
    if (area == 0) {
      return;
    }

    Vector2i leftTop = game.ScreenToImage(left, top);
    Vector2i rightBottom = game.ScreenToImage(right, bottom);
    Rectangle crop = Rectangle.FromLTRB(leftTop.X, leftTop.Y, rightBottom.X, rightBottom.Y);
    // FIXME: make sure this doesn't exceed image.Bounds.
    // FIXME: once set, display it properly in the PhotoBox.
    activePhoto.CropRectangle = crop;
    Console.WriteLine(crop);
  }

  public void Draw(UiGeometry geometry, Game game) {
    var (left, right, top, bottom) = GetCrop();
    int area = (right - left) * (bottom - top);

    if (area == 0) {
      return;
    }
    Color4 shadeColor = new Color4(0, 0, 0, 0.75f);
    game.DrawFilledBox(new Box2i(0, 0, left, geometry.PhotoBox.Max.Y), shadeColor);
    game.DrawFilledBox(new Box2i(left, 0, geometry.PhotoBox.Max.X, top), shadeColor);
    game.DrawFilledBox(new Box2i(left, bottom, geometry.PhotoBox.Max.X, geometry.PhotoBox.Max.Y), shadeColor);
    game.DrawFilledBox(new Box2i(right, top, geometry.PhotoBox.Max.X, bottom), shadeColor);
    game.DrawBox(new Box2i(left, top, right, bottom), 1, Color4.White);
    game.DrawBox(new Box2i(left - 1, top - 1 , right + 1, bottom + 1), 1, Color4.Black);
    game.DrawBox(new Box2i(left - 2, top - 2 , right + 2, bottom + 2), 1, Color4.White);
    game.DrawHorizontalLine(left, Util.Lerp(top, bottom, 1.0 / 3), right, Color4.White);
    game.DrawHorizontalLine(left, Util.Lerp(top, bottom, 2.0 / 3), right, Color4.White);
    game.DrawVerticalLine(Util.Lerp(left, right, 1.0 / 3), top, bottom, Color4.White);
    game.DrawVerticalLine(Util.Lerp(left, right, 2.0 / 3), top, bottom, Color4.White);
  }

  public string Status() {
    return "[crop] " + status;
  }
}

// FIXME: this should probably be IDisposable?
public class Photo {
  public string Filename;
  public bool Loaded = false;
  public long LastTouch = 0;
  public Vector2i Size;
  public DateTime DateTimeOriginal;
  public string CameraModel = "";
  public string LensModel = "";
  public string ShortLensModel = "";
  public string FocalLength = "<unk>";
  public string FNumber = "<unk>";
  public string ExposureTime = "<unk>";
  public string IsoSpeed = "<unk>";
  public int Rating = 0;
  public ushort Orientation = 1;
  public Rectangle CropRectangle = Rectangle.Empty;

  private static long touchCounter = 0;
  private Texture texture;
  private Texture placeholder;
  private Image<Rgba32>? image = null;

  public Photo(string filename, Texture placeholder) {
    Filename = filename;
    this.placeholder = placeholder;
    texture = placeholder;

    DateTime creationTime = File.GetCreationTime(filename);  // Local time.
    DateTimeOriginal = creationTime;
    ImageInfo info = Image.Identify(filename);
    Size = new(info.Size.Width, info.Size.Height);
    Rating = ParseRating(info.Metadata.XmpProfile);
    ParseExif(info.Metadata.ExifProfile);
  }

  public async void LoadAsync() {
    // We don't assign to this.image until Load() is done, because we might
    // edit the image due to rotation (etc) and don't want to try generating
    // a texture for it until that's already happened.
    LastTouch = touchCounter++;
    Image<Rgba32> tmp = await Image.LoadAsync<Rgba32>(Filename);
    Util.RotateImageFromExif(tmp, Orientation);
    image = tmp;
  }

  public void Unload() {
    Loaded = false;
    if (texture != placeholder) {
      texture.Dispose();
      texture = placeholder;
    }
  }

  public async void SaveAsJpegAsync(string outputRoot, JpegEncoder encoder) {
    // FIXME: if nothing was changed about this image, just copy the file bytes directly, possibly with metadata changed?
    string directory = System.IO.Path.Combine(
        outputRoot,
        String.Format("{0:D4}", DateTimeOriginal.Year),
        String.Format("{0:D2}", DateTimeOriginal.Month),
        String.Format("{0:D2}", DateTimeOriginal.Day));
    Directory.CreateDirectory(directory);
    string filename = System.IO.Path.Combine(directory, System.IO.Path.GetFileName(Filename));
    Console.WriteLine("saving " + filename);
    // FIXME: add comments / captions as ImageDescription?
    // FIXME: strip some Exif tags for privacy reasons?
    // FIXME: warn if the file already exists?
    using (Image<Rgba32> image = await Image.LoadAsync<Rgba32>(Filename)) {
      Util.RotateImageFromExif(image, Orientation);
      if (CropRectangle != Rectangle.Empty) {
        image.Mutate(x => x.Crop(CropRectangle));
      }

      ExifProfile exif = image.Metadata.ExifProfile ?? new();
      exif.SetValue<ushort>(ExifTag.Orientation, 1);
      exif.SetValue<string>(ExifTag.Artist, "Colin McMillen");
      exif.SetValue<string>(ExifTag.Copyright, "Colin McMillen");
      exif.SetValue<string>(ExifTag.Software, "Totte");
      exif.SetValue<ushort>(ExifTag.Rating, (ushort) Rating);
      DateTime now = DateTime.Now;
      string datetime = String.Format(
        "{0:D4}:{1:D2}:{2:D2} {3:D2}:{4:D2}:{5:D2}",
        now.Year, now.Month, now.Day, now.Hour, now.Minute, now.Second);
      exif.SetValue<string>(ExifTag.DateTime, datetime);

      image.Metadata.XmpProfile = UpdateXmp(image.Metadata.XmpProfile);

      await image.SaveAsync(filename, encoder);
    }
  }

  private XElement? GetXmpRoot(XmpProfile? xmp) {
    if (xmp == null) {
      return null;
    }
    XDocument? doc = xmp.GetDocument();
    if (doc == null) {
      return null;
    }
    return doc.Root;
  }

  private int ParseRating(XmpProfile? xmp) {
    XElement? root = GetXmpRoot(xmp);
    if (root == null) {
      return 0;
    }
    foreach (XElement elt in root.Descendants()) {
      if (elt.Name == "{http://ns.adobe.com/xap/1.0/}Rating") {
        int rating = 0;
        if (int.TryParse(elt.Value, out rating)) {
          return rating;
        }
      }
    }
    return 0;
  }

  private XmpProfile? UpdateXmp(XmpProfile? xmp) {
    if (xmp == null) {
      return null;
    }
    string xmlIn = Encoding.UTF8.GetString(xmp.ToByteArray());
    int index = xmlIn.IndexOf("</xmp:Rating>");
    if (index == -1) {
      return xmp;
    }
    string xmlOut = xmlIn.Substring(0, index - 1) + Rating.ToString() + xmlIn.Substring(index);
    return new XmpProfile(Encoding.UTF8.GetBytes(xmlOut));
  }

  // Exif (and other image metadata) reference, from the now-defunct Metadata Working Group:
  // https://web.archive.org/web/20180919181934/http://www.metadataworkinggroup.org/pdf/mwg_guidance.pdf
  //
  // Specifically:
  //
  // In general, date/time metadata is being used to describe the following scenarios:
  // * Date/time original specifies when a photo was taken
  // * Date/time digitized specifies when an image was digitized
  // * Date/time modified specifies when a file was modified by the user
  //
  // Original Date/Time – Creation date of the intellectual content (e.g. the photograph), rather than the creation date of the content being shown
  // Exif DateTimeOriginal (36867, 0x9003) and SubSecTimeOriginal (37521, 0x9291)
  // IPTC DateCreated (IIM 2:55, 0x0237) and TimeCreated (IIM 2:60, 0x023C)
  // XMP (photoshop:DateCreated)
  //
  // Digitized Date/Time – Creation date of the digital representation
  // Exif DateTimeDigitized (36868, 0x9004) and SubSecTimeDigitized (37522, 0x9292)
  // IPTC DigitalCreationDate (IIM 2:62, 0x023E) and DigitalCreationTime (IIM 2:63, 0x023F)
  // XMP (xmp:CreateDate)
  //
  // Modification Date/Time – Modification date of the digital image file
  // Exif DateTime (306, 0x132) and SubSecTime (37520, 0x9290)
  // XMP (xmp:ModifyDate)
  //
  // See also: https://exiftool.org/TagNames/EXIF.html
  private void ParseExif(ExifProfile? exifs) {
    if (exifs == null) {
      return;
    }

    IExifValue<ushort>? orientation;
    if (exifs.TryGetValue(ExifTag.Orientation, out orientation)) {
      Orientation = orientation.Value;
    }

    IExifValue<string>? model;
    if (exifs.TryGetValue(ExifTag.Model, out model)) {
      CameraModel = model.Value ?? "";
    }

    IExifValue<string>? lensModel;
    if (exifs.TryGetValue(ExifTag.LensModel, out lensModel)) {
      LensModel = lensModel.Value ?? "";
      ShortLensModel = GetShortLensModel(LensModel);
    }

    IExifValue<Rational>? focalLength;
    if (exifs.TryGetValue(ExifTag.FocalLength, out focalLength)) {
      Rational r = focalLength.Value;
      FocalLength = $"{r.Numerator / r.Denominator}mm";
    }

    IExifValue<Rational>? fNumber;
    if (exifs.TryGetValue(ExifTag.FNumber, out fNumber)) {
      Rational r = fNumber.Value;
      if (r.Numerator % r.Denominator == 0) {
        FNumber = $"f/{r.Numerator / r.Denominator}";
      } else {
        int fTimesTen = (int) Math.Round(10f * r.Numerator / r.Denominator);
        FNumber = $"f/{fTimesTen / 10}.{fTimesTen % 10}";
      }
    }

    // FIXME: could also show ExposureBiasValue, ExposureMode, ExposureProgram?
    IExifValue<Rational>? exposureTime;
    if (exifs.TryGetValue(ExifTag.ExposureTime, out exposureTime)) {
      Rational r = exposureTime.Value;
      if (r.Numerator == 1) {
        ExposureTime = $"1/{r.Denominator}";
      } else if (r.Numerator == 10) {
        ExposureTime = $"1/{r.Denominator / 10}";
      } else if (r.Denominator == 1) {
        ExposureTime = $"{r.Numerator }\"";
      } else if (r.Denominator == 10) {
        ExposureTime = $"{r.Numerator / 10}.{r.Numerator % 10}\"";
      } else {
        Console.WriteLine($"*** WARNING: unexpected ExposureTime: {r.Numerator}/{r.Denominator}");
        ExposureTime = r.ToString();
      }
    }

    IExifValue<ushort[]>? isoSpeed;
    if (exifs.TryGetValue(ExifTag.ISOSpeedRatings, out isoSpeed)) {
      ushort[]? iso = isoSpeed.Value;
      if (iso != null) {
        if (iso.Length != 1) {
          Console.WriteLine($"*** WARNING: unexpected ISOSpeedRatings array length: {iso.Length}");
        }
        if (iso.Length >= 1) {
          IsoSpeed = $"ISO {iso[0]}";
        }
      }
    }

    // FIXME: there is also a SubSecTimeOriginal tag we could use to get fractional seconds.
    // FIXME: I think the iPhone stores time in UTC but other cameras report it in local time.
    IExifValue<string>? dateTimeOriginal;
    if (exifs.TryGetValue(ExifTag.DateTimeOriginal, out dateTimeOriginal)) {
      DateTime date;
      if (DateTime.TryParseExact(
          dateTimeOriginal.Value ?? "",
          "yyyy:MM:dd HH:mm:ss",
          System.Globalization.CultureInfo.InvariantCulture,
          System.Globalization.DateTimeStyles.AssumeLocal,
          out date)) {
        DateTimeOriginal = date;
      } else {
        Console.WriteLine($"*** WARNING: unexpected DateTimeOriginal value: {dateTimeOriginal.Value}");
      }
    }
  }

  public string GetShortLensModel(string lensModel) {
    // Example Canon RF lens names:
    // RF16mm F2.8 STM
    // RF24-105mm F4-7.1 IS STM
    // RF35mm F1.8 MACRO IS STM
    // RF100-400mm F5.6-8 IS USM
    string[] tokens = lensModel.Split(' ');
    string result = "";
    foreach (string token in tokens) {
      if (token == "STM" || token == "IS" || token == "USM") {
        continue;
      }
      result += token + " ";
    }
    return result.Trim();
  }

  public Texture Texture() {
    LastTouch = touchCounter++;
    if (texture == placeholder && image != null) {
      // The texture needs to be created on the GL thread, so we instantiate
      // it here (since this is called from OnRenderFrame), as long as the
      // image is ready to go.
      texture = new Texture(image);
      image.Dispose();
      image = null;
      Loaded = true;
    }
    return texture;
  }

  public string Description() {
    string date = DateTimeOriginal.ToString("yyyy-MM-dd HH:mm:ss");
    return String.Format(
        "{0,6}  {1,-5}  {2,-7} {3,-10} {4}    {5,-20}    {6}",
        FocalLength, FNumber, ExposureTime, IsoSpeed, date, ShortLensModel, Filename);
  }
}

public class Texture : IDisposable {
  public int Handle;
  public Vector2i Size;

  private static int maxHandle = -1;
  private bool disposedValue = false;

  public Texture(Image<Rgba32> image) {
    Size = new Vector2i(image.Width, image.Height);
    byte[] pixelBytes = new byte[Size.X * Size.Y * Unsafe.SizeOf<Rgba32>()];
    image.CopyPixelDataTo(pixelBytes);

    Handle = GL.GenTexture();
    if (Handle > maxHandle) {
      // Console.WriteLine("GL.GenTexture #" + Handle);
      maxHandle = Handle;
    }
    GL.ActiveTexture(TextureUnit.Texture0);
    GL.BindTexture(TextureTarget.Texture2D, Handle);
    GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Rgba, Size.X, Size.Y, 0, PixelFormat.Rgba, PixelType.UnsignedByte, pixelBytes);
    //GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int) TextureMinFilter.LinearMipmapLinear);
    GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int) TextureMinFilter.Linear);
    GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int) TextureMagFilter.Nearest);
    GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int) TextureWrapMode.ClampToBorder);
    GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int) TextureWrapMode.ClampToBorder);
    float[] borderColor = { 0.0f, 0.0f, 0.0f, 1.0f };
    GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureBorderColor, borderColor);
    // FIXME: should we use mipmaps?
    //GL.GenerateMipmap(GenerateMipmapTarget.Texture2D);
  }

  protected virtual void Dispose(bool disposing) {
    if (!disposedValue) {
      GL.DeleteTexture(Handle);
      disposedValue = true;
    }
  }

  ~Texture() {
    if (!disposedValue) {
      Console.WriteLine("~Texture(): resource leak? Dispose() should be called manually.");
    }
  }

  public void Dispose() {
    Dispose(true);
    GC.SuppressFinalize(this);
  }
}

public class UiGeometry {
  public static Vector2i MIN_WINDOW_SIZE = new(1024, 768);
  private static CameraInfo activeCamera = CameraInfo.CANON_EOS_R6M2;

  public readonly Vector2i WindowSize;
  public readonly Box2i ThumbnailBox;
  public readonly List<Box2i> ThumbnailBoxes = new();
  public readonly List<Box2i> StarBoxes = new();
  public readonly Box2i PhotoBox;
  public readonly Box2i StatusBox;

  public UiGeometry() : this(MIN_WINDOW_SIZE, 0) {}

  public UiGeometry(Vector2i windowSize, int starSize) {
    WindowSize = windowSize;

    int numThumbnails = Math.Max(WindowSize.Y / 100, 1);
    int thumbnailHeight = WindowSize.Y / numThumbnails;
    int thumbnailWidth = (int) 1.0 * thumbnailHeight * activeCamera.Resolution.X / activeCamera.Resolution.Y;

    Console.WriteLine($"thumbnail size: {thumbnailWidth} x {thumbnailHeight}");
    for (int i = 0; i < numThumbnails; i++) {
      Box2i box = Util.MakeBox(WindowSize.X - thumbnailWidth, i * thumbnailHeight, thumbnailWidth, thumbnailHeight);
      ThumbnailBoxes.Add(box);
    }

    int statusBoxHeight = 40;
    int statusBoxPadding = 4;
    PhotoBox = new Box2i(0, 0, WindowSize.X - thumbnailWidth, WindowSize.Y - statusBoxHeight - statusBoxPadding);
    StatusBox = new Box2i(0, WindowSize.Y - statusBoxHeight, WindowSize.X - thumbnailWidth, WindowSize.Y);
    ThumbnailBox = new Box2i(ThumbnailBoxes[0].Min.X, ThumbnailBoxes[0].Min.Y, WindowSize.X, WindowSize.Y);

    int starSpacing = 10;
    int starBoxLeft = (int) (PhotoBox.Center.X - 2.5 * starSize - starSpacing * 2);
    for (int i = 0; i < 5; i++) {
      Box2i box = Util.MakeBox(starBoxLeft + i * (starSize + starSpacing), PhotoBox.Max.Y - starSize - 10, starSize, starSize);
      StarBoxes.Add(box);
    }
  }
}

public static class Util {
  public const float PI = (float) Math.PI;

  public static int Lerp(int start, int end, double fraction) {
    return start + (int) ((end - start) * fraction);
  }

  public static Box2i MakeBox(int left, int top, int width, int height) {
    return new Box2i(left, top, left + width, top + height);
  }

  public static Image<Rgba32> MakeImage(float width, float height) {
    return new((int) Math.Ceiling(width), (int) Math.Ceiling(height));
  }

  // https://sirv.com/help/articles/rotate-photos-to-be-upright/
  public static void RotateImageFromExif(Image<Rgba32> image, ushort orientation) {
    if (orientation <= 1) {
      return;
    }
    // FIXME: I'm not convinced that all of these are correct, especially the
    // cases that involve flipping (because whether you're flipping before or
    // after rotation matters.)
    var operations = new Dictionary<ushort, (RotateMode, FlipMode)> {
      { 2, (RotateMode.None, FlipMode.Horizontal) },
      { 3, (RotateMode.Rotate180, FlipMode.None) },
      { 4, (RotateMode.None, FlipMode.Vertical) },
      { 5, (RotateMode.Rotate90, FlipMode.Vertical) },
      { 6, (RotateMode.Rotate90, FlipMode.None) },
      { 7, (RotateMode.Rotate270, FlipMode.Vertical) },
      { 8, (RotateMode.Rotate270, FlipMode.None) },
    };
    var (rotate, flip) = operations[orientation];
    image.Mutate(x => x.RotateFlip(rotate, flip));
  }

  public static Texture RenderText(string text) {
    return RenderText(text, 16);
  }

  public static Texture RenderText(string text, int size) {
    // Make sure that 0-length text doesn't end up as a 0-size texture, which
    // might cause problems.
    if (text.Length == 0) {
      text = " ";
    }
    Font font = SystemFonts.CreateFont("Consolas", size, FontStyle.Bold);
    TextOptions options = new(font);
    FontRectangle rect = TextMeasurer.Measure(text, new TextOptions(font));
    Image<Rgba32> image = MakeImage(rect.Width, rect.Height);
    IBrush brush = Brushes.Solid(Color.White);
    image.Mutate(x => x.DrawText(options, text, brush));
    Texture texture = new Texture(image);
    image.Dispose();
    return texture;
  }

  // FIXME: make a real icon stored as a PNG...
  public static OpenTK.Windowing.Common.Input.Image[] RenderAppIcon() {
    int size = 64;
    Font font = SystemFonts.CreateFont("MS Mincho", size, FontStyle.Bold);
    TextOptions options = new(font);
    Image<Rgba32> image = MakeImage(size, size);
    IBrush brush = Brushes.Solid(Color.Black);
    image.Mutate(x => x.DrawText(options, "撮", brush));
    byte[] pixelBytes = new byte[size * size * 4];
    image.CopyPixelDataTo(pixelBytes);
    image.Dispose();
    OpenTK.Windowing.Common.Input.Image opentkImage = new(size, size, pixelBytes);
    return new OpenTK.Windowing.Common.Input.Image[]{ opentkImage };
  }

  public static Texture RenderStar(float radius, bool filled) {
    IPath path = new Star(x: radius, y: radius + 1, prongs: 5, innerRadii: radius * 0.4f, outerRadii: radius, angle: Util.PI);
    // We add a little bit to the width & height because the reported
    // path.Bounds are often a little tighter than they should be & a couple
    // pixels end up obviously missing...
    Image<Rgba32> image = MakeImage(path.Bounds.Width + 2, path.Bounds.Height + 2);
    IBrush brush = Brushes.Solid(Color.White);
    IPen white = Pens.Solid(Color.White, 1.5f);
    IPen black = Pens.Solid(Color.Black, 3f);
    image.Mutate(x => x.Draw(black, path));
    if (filled) {
      image.Mutate(x => x.Fill(brush, path));
    }
    image.Mutate(x => x.Draw(white, path));
    Texture texture = new Texture(image);
    image.Dispose();
    return texture;
  }
}

public class Game : GameWindow {
  public Game(GameWindowSettings gwSettings, NativeWindowSettings nwSettings) : base(gwSettings, nwSettings) {
    activeTool = viewTool;
  }

  private static string outputRoot = @"c:\users\colin\desktop\totte-output";
  // private static string outputRoot = @"c:\users\colin\pictures\photos";

  private static Texture TEXTURE_WHITE = new(new Image<Rgba32>(1, 1, new Rgba32(255, 255, 255)));
  private static Texture TEXTURE_BLACK = new(new Image<Rgba32>(1, 1, new Rgba32(0, 0, 0)));
  private static Texture STAR_FILLED = Util.RenderStar(20, true);