little changes to thumbnails / image load/unload constants

Program.cs

@@ -438,7 +438,7 @@ public class UiGeometry {
   public UiGeometry(Vector2i windowSize) {
     WindowSize = windowSize;
 
-    int numThumbnails = 20;
+    int numThumbnails = 15;
     int thumbnailHeight = WindowSize.Y / numThumbnails;
     int thumbnailWidth = (int) 1.0 * thumbnailHeight * activeCamera.Resolution.X / activeCamera.Resolution.Y;
     for (int i = 0; i < numThumbnails; i++) {
@@ -707,7 +707,7 @@ public class Game : GameWindow {
     // string[] files = Directory.GetFiles(@"c:\users\colin\pictures\photos\2023\07\14\");
     // string[] files = Directory.GetFiles(@"G:\DCIM\100EOSR6\");
     // string[] files = Directory.GetFiles(@"C:\Users\colin\Pictures\photos\2018\06\23");
-    string[] files = Directory.GetFiles(@"C:\Users\colin\Desktop\Germany all\105D7000");
+    string[] files = Directory.GetFiles(@"C:\Users\colin\Desktop\Germany all\104D7000");
     // string[] files = Directory.GetFiles(@"C:\Users\colin\Desktop\many-birds\");
 
     for (int i = 0; i < files.Count(); i++) {
@@ -736,9 +736,9 @@ public class Game : GameWindow {
   }
 
   private async void LoadAndUnloadImagesAsync() {
-    int minUnloadedImage = Math.Max(0, photoIndex - 40);
-    int maxUnloadedImage = Math.Min(photoIndex + 40, photos.Count - 1);
-    int minLoadedImage = Math.Max(0, photoIndex - 20);
+    int minUnloadedImage = Math.Max(0, photoIndex - 20);
+    int maxUnloadedImage = Math.Min(photoIndex + 30, photos.Count - 1);
+    int minLoadedImage = Math.Max(0, photoIndex - 10);
     int maxLoadedImage = Math.Min(photoIndex + 20, photos.Count - 1);
     // First, unload images that are far outside our window.
     // FIXME: also cancel any in-progress loading tasks that have moved outside our window.