From bdaa6a191005498f429142e3ddac039e589b3c83 Mon Sep 17 00:00:00 2001
From: Alexander Alekhin <alexander.a.alekhin@gmail.com>
Date: Wed, 6 Oct 2021 19:09:22 +0000
Subject: [PATCH] highgui: repair Qt backend

---
 modules/highgui/CMakeLists.txt | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/modules/highgui/CMakeLists.txt b/modules/highgui/CMakeLists.txt
index 3ef1535d2d..c5541241a4 100644
--- a/modules/highgui/CMakeLists.txt
+++ b/modules/highgui/CMakeLists.txt
@@ -51,6 +51,8 @@ set(OPENCV_HIGHGUI_BUILTIN_BACKEND "")
 
 if(HAVE_QT)
   set(OPENCV_HIGHGUI_BUILTIN_BACKEND "QT${QT_VERSION_MAJOR}")
+  add_definitions(-DHAVE_QT)
+
   if(QT_VERSION_MAJOR GREATER 4)
     # "Automoc" doesn't work properly with opencv_world build, use QT<ver>_WRAP_CPP() directly
     #set(CMAKE_AUTOMOC ON)
@@ -75,6 +77,7 @@ if(HAVE_QT)
 
     set(qt_deps Core Gui Widgets Test Concurrent)
     if(HAVE_QT_OPENGL)
+      add_definitions(-DHAVE_QT_OPENGL)
       list(APPEND qt_deps OpenGL)
     endif()