From babef459b0a68a6dd425b724208bc38eee678bfe Mon Sep 17 00:00:00 2001
From: Christian Speckner <christian.speckner@mayflower.de>
Date: Wed, 30 Aug 2023 22:40:31 +0200
Subject: [PATCH] Account for HiDPI scaling when validating QIS blitter.

---
 src/common/FBSurfaceSDL2.cxx | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/common/FBSurfaceSDL2.cxx b/src/common/FBSurfaceSDL2.cxx
index 288341b4f..2de4aa737 100644
--- a/src/common/FBSurfaceSDL2.cxx
+++ b/src/common/FBSurfaceSDL2.cxx
@@ -281,8 +281,12 @@ void FBSurfaceSDL2::applyAttributes()
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void FBSurfaceSDL2::setScalingInterpolation(ScalingInterpolation interpolation)
 {
-  if (interpolation == ScalingInterpolation::sharp
-      && mySrcGUIR.h() >= myDstGUIR.h())
+  if (interpolation == ScalingInterpolation::sharp &&
+      (
+        static_cast<int>(mySrcGUIR.h()) >= myBackend.scaleY(myDstGUIR.h()) ||
+        static_cast<int>(mySrcGUIR.w()) >= myBackend.scaleX(myDstGUIR.w())
+      )
+  )
     interpolation = ScalingInterpolation::blur;
 
   if (interpolation == myInterpolationMode) return;