WIP Image imports and file access

2024-06-28 21:03:56 +01:00
parent b5a2bab691
commit f933afc24f
17 changed files with 192 additions and 40 deletions
@@ -0,0 +1,53 @@
+using Avalonia.Media.Imaging;
+using SkiaSharp;
+
+namespace Toolkit.Avalonia;
+
+public class ImageResizer : 
+    IImageResizer
+{
+    public Bitmap Resize(Stream stream, 
+        int targetWidth, 
+        int targetHeight, 
+        bool maintainAspectRatio)
+    {
+        using SKBitmap original = SKBitmap.Decode(stream);
+
+        float widthRatio = (float)targetWidth / original.Width;
+        float heightRatio = (float)targetHeight / original.Height;
+        float scale = maintainAspectRatio ? Math.Max(widthRatio, heightRatio) : Math.Min(widthRatio, heightRatio);
+
+        int newWidth = (int)(original.Width * scale);
+        int newHeight = (int)(original.Height * scale);
+
+        using SKBitmap resized = new(newWidth, newHeight);
+        using SKCanvas canvas = new(resized);
+
+        canvas.Clear(SKColors.Transparent);
+        canvas.DrawBitmap(original, new SKRect(0, 0, newWidth, newHeight));
+
+        SKBitmap cropped;
+        if (maintainAspectRatio)
+        {
+            int cropX = (newWidth - targetWidth) / 2;
+            int cropY = (newHeight - targetHeight) / 2;
+
+            cropped = new SKBitmap(targetWidth, targetHeight);
+            using SKCanvas croppedCanvas = new(cropped);
+            SKRect cropRect = new(cropX, cropY, cropX + targetWidth, cropY + targetHeight);
+            croppedCanvas.Clear(SKColors.Transparent);
+            croppedCanvas.DrawBitmap(resized, cropRect, new SKRect(0, 0, targetWidth, targetHeight));
+        }
+        else
+        {
+            cropped = resized;
+        }
+
+        using SKImage image = SKImage.FromBitmap(cropped);
+        using MemoryStream outputStream = new();
+        image.Encode(SKEncodedImageFormat.Png, 100).SaveTo(outputStream);
+        outputStream.Seek(0, SeekOrigin.Begin);
+
+        return new Bitmap(outputStream);
+    }
+}