From 76e631ba0eae63371b796dc2035e816122edb3b9 Mon Sep 17 00:00:00 2001
From: Martin Reboredo <yakoyoku@gmail.com>
Date: Sun, 30 Jan 2022 20:08:03 -0300
Subject: [PATCH] Fix build failure in #764

---
 Gui/Gui.pro  | 9 +++++++--
 Gui/GuiFwd.h | 7 ++++++-
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/Gui/Gui.pro b/Gui/Gui.pro
index bda80d9691..0d27bb0b80 100644
--- a/Gui/Gui.pro
+++ b/Gui/Gui.pro
@@ -22,8 +22,13 @@ TEMPLATE = lib
 CONFIG += staticlib
 CONFIG += moc rcc
 CONFIG += boost opengl qt cairo python shiboken pyside 
-QT += gui core opengl network
-greaterThan(QT_MAJOR_VERSION, 4): QT += concurrent
+QT += gui core network
+
+greaterThan(QT_MAJOR_VERSION, 4) {
+    QT += concurrent
+} else {
+    QT += opengl
+}
 
 GUI_WRAPPER_DIR = Qt$${QT_MAJOR_VERSION}/NatronGui
 ENGINE_WRAPPER_DIR = Qt$${QT_MAJOR_VERSION}/NatronEngine
diff --git a/Gui/GuiFwd.h b/Gui/GuiFwd.h
index 511c16f9aa..0810859b30 100644
--- a/Gui/GuiFwd.h
+++ b/Gui/GuiFwd.h
@@ -49,7 +49,6 @@ class QFont;
 class QFontComboBox;
 class QFontMetrics;
 class QFrame;
-class QOpenGLShaderProgram;
 class QGraphicsLineItem;
 class QGraphicsPolygonItem;
 class QGraphicsScene;
@@ -95,6 +94,12 @@ class QWheelEvent;
 class QWidget;
 typedef boost::shared_ptr<QUndoStack> QUndoStackPtr;
 
+#if QT_VERSION >= QT_VERSION_CHECK(5, 4, 0)
+class QOpenGLShaderProgram;
+#else
+typedef QGLShaderProgram QOpenGLShaderProgram;
+#endif
+
 // Natron Gui
 NATRON_NAMESPACE_ENTER
 class AboutWindow;