From 27474c9563f504512830dd6e924fb631bbba4ef0 Mon Sep 17 00:00:00 2001
From: bruvzg <7645683+bruvzg@users.noreply.github.com>
Date: Thu, 1 Aug 2024 10:30:46 +0300
Subject: [PATCH] [Windows] Check if transparency is enabled in the project
 setting before applying DWM blur.

---
 platform/windows/display_server_windows.cpp | 55 +++++++++++----------
 1 file changed, 29 insertions(+), 26 deletions(-)

diff --git a/platform/windows/display_server_windows.cpp b/platform/windows/display_server_windows.cpp
index 36f3f632d5..0a7f3157f3 100644
--- a/platform/windows/display_server_windows.cpp
+++ b/platform/windows/display_server_windows.cpp
@@ -1333,13 +1333,15 @@ DisplayServer::WindowID DisplayServerWindows::create_sub_window(WindowMode p_mod
 		wd.is_popup = true;
 	}
 	if (p_flags & WINDOW_FLAG_TRANSPARENT_BIT) {
-		DWM_BLURBEHIND bb;
-		ZeroMemory(&bb, sizeof(bb));
-		HRGN hRgn = CreateRectRgn(0, 0, -1, -1);
-		bb.dwFlags = DWM_BB_ENABLE | DWM_BB_BLURREGION;
-		bb.hRgnBlur = hRgn;
-		bb.fEnable = TRUE;
-		DwmEnableBlurBehindWindow(wd.hWnd, &bb);
+		if (OS::get_singleton()->is_layered_allowed()) {
+			DWM_BLURBEHIND bb;
+			ZeroMemory(&bb, sizeof(bb));
+			HRGN hRgn = CreateRectRgn(0, 0, -1, -1);
+			bb.dwFlags = DWM_BB_ENABLE | DWM_BB_BLURREGION;
+			bb.hRgnBlur = hRgn;
+			bb.fEnable = TRUE;
+			DwmEnableBlurBehindWindow(wd.hWnd, &bb);
+		}
 
 		wd.layered_window = true;
 	}
@@ -2119,28 +2121,29 @@ void DisplayServerWindows::window_set_flag(WindowFlags p_flag, bool p_enabled, W
 		} break;
 		case WINDOW_FLAG_TRANSPARENT: {
 			if (p_enabled) {
-				//enable per-pixel alpha
-
-				DWM_BLURBEHIND bb;
-				ZeroMemory(&bb, sizeof(bb));
-				HRGN hRgn = CreateRectRgn(0, 0, -1, -1);
-				bb.dwFlags = DWM_BB_ENABLE | DWM_BB_BLURREGION;
-				bb.hRgnBlur = hRgn;
-				bb.fEnable = TRUE;
-				DwmEnableBlurBehindWindow(wd.hWnd, &bb);
-
+				// Enable per-pixel alpha.
+				if (OS::get_singleton()->is_layered_allowed()) {
+					DWM_BLURBEHIND bb;
+					ZeroMemory(&bb, sizeof(bb));
+					HRGN hRgn = CreateRectRgn(0, 0, -1, -1);
+					bb.dwFlags = DWM_BB_ENABLE | DWM_BB_BLURREGION;
+					bb.hRgnBlur = hRgn;
+					bb.fEnable = TRUE;
+					DwmEnableBlurBehindWindow(wd.hWnd, &bb);
+				}
 				wd.layered_window = true;
 			} else {
-				//disable per-pixel alpha
+				// Disable per-pixel alpha.
 				wd.layered_window = false;
-
-				DWM_BLURBEHIND bb;
-				ZeroMemory(&bb, sizeof(bb));
-				HRGN hRgn = CreateRectRgn(0, 0, -1, -1);
-				bb.dwFlags = DWM_BB_ENABLE | DWM_BB_BLURREGION;
-				bb.hRgnBlur = hRgn;
-				bb.fEnable = FALSE;
-				DwmEnableBlurBehindWindow(wd.hWnd, &bb);
+				if (OS::get_singleton()->is_layered_allowed()) {
+					DWM_BLURBEHIND bb;
+					ZeroMemory(&bb, sizeof(bb));
+					HRGN hRgn = CreateRectRgn(0, 0, -1, -1);
+					bb.dwFlags = DWM_BB_ENABLE | DWM_BB_BLURREGION;
+					bb.hRgnBlur = hRgn;
+					bb.fEnable = FALSE;
+					DwmEnableBlurBehindWindow(wd.hWnd, &bb);
+				}
 			}
 		} break;
 		case WINDOW_FLAG_NO_FOCUS: {