From c698d1ea1e19d292df4669d8190e340bb0968685 Mon Sep 17 00:00:00 2001
From: taj-ny <79316397+taj-ny@users.noreply.github.com>
Date: Thu, 5 Dec 2024 18:57:35 +0100
Subject: [PATCH] add support for KDecoration3

---
 CMakeLists.txt     | 10 +++++++++-
 src/CMakeLists.txt |  7 +++++--
 src/blur.cpp       | 20 ++++++++++++++++++--
 3 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b86759d43..7e155d254 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -73,7 +73,15 @@ if(${KWin_VERSION} VERSION_GREATER_EQUAL 6.1.90)
     add_compile_definitions(KWIN_6_2_OR_GREATER)
 endif()
 
-find_package(KDecoration2 REQUIRED)
+find_package(KDecoration2)
+find_package(KDecoration3)
+if (${KDecoration3_FOUND})
+    add_compile_definitions(KDECORATION3)
+endif()
+if(NOT ${KDecoration3_FOUND} AND NOT ${KDecoration2_FOUND})
+    message(fatal_error "Could not find KDecoration2 or KDecoration3.")
+endif()
+
 
 find_package(KWinDBusInterface CONFIG REQUIRED)
 
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 2ce5f865c..e659aa2a5 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -28,8 +28,11 @@ target_link_libraries(forceblur PRIVATE
     KWin::kwin
 
     KF6::ConfigGui
-
-    KDecoration2::KDecoration
 )
+if (${KDecoration3_FOUND})
+    target_link_libraries(forceblur PRIVATE KDecoration3::KDecoration)
+else()
+    target_link_libraries(forceblur PRIVATE KDecoration2::KDecoration)
+endif()
 
 install(TARGETS forceblur DESTINATION ${KDE_INSTALL_PLUGINDIR}/kwin/effects/plugins)
diff --git a/src/blur.cpp b/src/blur.cpp
index 72f435167..6bf17335e 100644
--- a/src/blur.cpp
+++ b/src/blur.cpp
@@ -41,7 +41,12 @@
 #include <KConfigGroup>
 #include <KSharedConfig>
 
+#ifdef KDECORATION3
+#include <KDecoration3/Decoration>
+#else
 #include <KDecoration2/Decoration>
+#endif
+
 #include <utility>
 
 Q_LOGGING_CATEGORY(KWIN_BLUR, "kwin_better_blur", QtWarningMsg)
@@ -420,7 +425,13 @@ void BlurEffect::setupDecorationConnections(EffectWindow *w)
         return;
     }
 
-    connect(w->decoration(), &KDecoration2::Decoration::blurRegionChanged, this, [this, w]() {
+    connect(w->decoration(),
+#ifdef KDECORATION3
+        &KDecoration3::Decoration::blurRegionChanged
+#else
+        &KDecoration2::Decoration::blurRegionChanged
+#endif
+        , this, [this, w]() {
         updateBlurRegion(w);
     });
 }
@@ -464,7 +475,12 @@ QRegion BlurEffect::decorationBlurRegion(const EffectWindow *w) const
         return QRegion();
     }
 
-    QRegion decorationRegion = QRegion(w->decoration()->rect()) - w->contentsRect().toRect();
+    QRect decorationRect = w->decoration()->rect()
+#ifdef KDECORATION3
+        .toAlignedRect()
+#endif
+        ;
+    QRegion decorationRegion = QRegion(decorationRect) - w->contentsRect().toRect();
     //! we return only blurred regions that belong to decoration region
     return decorationRegion.intersected(w->decoration()->blurRegion());
 }