load Photos more async'ly

Program.cs

@@ -135,33 +135,39 @@ void main() {
   public int GetUniformLocation(string name) {
     return GL.GetUniformLocation(Handle, name);
   }
-
 }
 
+// FIXME: this should probably be IDisposable?
 public class Photo {
+  private string file;
   private Texture texture;
   private Texture placeholder;
-  private Image<Rgba32> image;
+  private Image<Rgba32>? image = null;
 
-  public Photo(Image<Rgba32> image, Texture placeholder) {
-    this.image = image;
+  public Photo(string file, Texture placeholder) {
+    this.file = file;
     this.placeholder = placeholder;
     texture = placeholder;
+  }
 
+  public async void Load() {
+    image = await Image.LoadAsync<Rgba32>(file);
     ExifProfile? exifs = image.Metadata.ExifProfile;
     if (exifs != null) {
       foreach (IExifValue exif in exifs.Values) {
         if (exif.Tag.ToString() == "Model") {
-          Console.WriteLine($"{exif.Tag}: {exif.GetValue()}");
+          Console.WriteLine($"{file} {exif.Tag}: {exif.GetValue()}");
         }
       }
     }
   }
 
   public Texture Texture() {
-   if (texture == placeholder) {
+   if (texture == placeholder && image != null) {
+    Console.WriteLine("making texture for " + file);
     texture = new Texture(image);
     image.Dispose();
+    image = null;
    }
    return texture;
  }
@@ -177,6 +183,7 @@ public class Texture : IDisposable {
     image.CopyPixelDataTo(pixelBytes);
 
     Handle = GL.GenTexture();
+    Console.WriteLine("GL.GenTexture #" + 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);
@@ -223,7 +230,7 @@ public class UiGeometry {
   public UiGeometry(Vector2i windowSize) {
     WindowSize = windowSize;
 
-    int numThumbnails = 20;
+    int numThumbnails = 10;
     int thumbnailHeight = WindowSize.Y / numThumbnails;
     int thumbnailWidth = (int) 1.0 * thumbnailHeight * activeCamera.Resolution.X / activeCamera.Resolution.Y;
     for (int i = 0; i < numThumbnails; i++) {
@@ -261,7 +268,6 @@ public class Game : GameWindow {
     1, 2, 3    // second triangle
   };
 
-  bool doneLoading = false;
   int VertexBufferObject;
   int ElementBufferObject;
   int VertexArrayObject;
@@ -355,22 +361,15 @@ public class Game : GameWindow {
     string[] files = Directory.GetFiles(@"c:\users\colin\pictures\photos\2023\07\14\");
     //string[] files = Directory.GetFiles(@"C:\Users\colin\Pictures\photos\2018\06\23");
 
-    List<Task<Image<Rgba32>>> imageTasks = new();
     for (int i = 0; i < files.Count(); i++) {
       string file = files[i];
       if (file.ToLower().EndsWith(".jpg")) {
-        imageTasks.Add(Image.LoadAsync<Rgba32>(file));
+        Photo photo = new Photo(file, TEXTURE_WHITE);
+        photos.Add(photo);
+        await Task.Run( () => { photo.Load(); });
+        Console.WriteLine("file " + i);
       }
     }
-    Console.WriteLine(DateTime.Now);
-    await Task.WhenAll(imageTasks);
-    Console.WriteLine(DateTime.Now);
-
-    foreach (Task<Image<Rgba32>> task in imageTasks) {
-      Photo photo = new(task.Result, TEXTURE_WHITE);
-      photos.Add(photo);
-    }
-    doneLoading = true;
   }
 
   protected override void OnUnload() {
@@ -379,9 +378,6 @@ public class Game : GameWindow {
 
   protected override void OnRenderFrame(FrameEventArgs e) {
     base.OnRenderFrame(e);
-    if (!doneLoading) {
-      return;
-    }
 
     GL.Clear(ClearBufferMask.ColorBufferBit);
     GL.BindBuffer(BufferTarget.ArrayBuffer, VertexBufferObject);