fix(screenshots): Read back screenshots in their own format

src/Sentry.Unity/SentryScreenshot.cs

@@ -2,7 +2,6 @@
 using System.Threading.Tasks;
 using Sentry.Extensibility;
 using UnityEngine;
-using UnityEngine.Experimental.Rendering;
 using UnityEngine.Rendering;
 
 namespace Sentry.Unity;
@@ -56,11 +55,13 @@ internal static void CaptureAsync(SentryUnityOptions options, Action<byte[]?> on
     {
         var renderTexture = CaptureIntoRenderTexture(options, Screen.width, Screen.height);
         var (width, height) = ((uint)renderTexture.width, (uint)renderTexture.height);
+        var format = renderTexture.graphicsFormat;
 
         try
         {
-            // The texture has to stay out of the pool until the readback is done with it
-            AsyncGPUReadback.Request(renderTexture, 0, TextureFormat.RGBA32, readback =>
+            // The texture has to stay out of the pool until the readback is done with it. Reading it back in its own
+            // format, as converting fails for formats the platform can't ReadPixels from, e.g. BGRA on Metal.
+            AsyncGPUReadback.Request(renderTexture, 0, readback =>
             {
                 RenderTexture.ReleaseTemporary(renderTexture);
 
@@ -77,7 +78,7 @@ internal static void CaptureAsync(SentryUnityOptions options, Action<byte[]?> on
                     byte[]? bytes = null;
                     try
                     {
-                        bytes = ImageConversion.EncodeArrayToJPG(pixels, GraphicsFormat.R8G8B8A8_UNorm, width, height,
+                        bytes = ImageConversion.EncodeArrayToJPG(pixels, format, width, height,
                             0, options.ScreenshotCompression);
                     }
                     catch (Exception e)

test/Sentry.Unity.Tests/SentryScreenshotTests.cs

@@ -1,5 +1,8 @@
+using System.Collections;
+using System.Threading.Tasks;
 using NUnit.Framework;
 using UnityEngine;
+using UnityEngine.TestTools;
 
 namespace Sentry.Unity.Tests;
 
@@ -61,4 +64,21 @@ public void CaptureScreenshot_RestoresActiveRenderTexture()
             Object.Destroy(gameTarget);
         }
     }
+
+    // Unity logs an error when the readback has to convert from a format it can't ReadPixels from, e.g. BGRA on Metal
+    [UnityTest]
+    public IEnumerator CaptureAsync_ReadsBackScreenshot()
+    {
+        if (!SystemInfo.supportsAsyncGPUReadback)
+        {
+            Assert.Ignore("Async GPU readback is not supported.");
+        }
+
+        var screenshot = new TaskCompletionSource<byte[]?>();
+
+        SentryScreenshot.CaptureAsync(new SentryUnityOptions(), bytes => screenshot.SetResult(bytes));
+        yield return new WaitUntil(() => screenshot.Task.IsCompleted);
+
+        Assert.IsNotEmpty(screenshot.Task.Result);
+    }
 }