From e68f76e6ab9457652d6de0712120695d2fbb81b8 Mon Sep 17 00:00:00 2001
From: John Preston <johnprestonmail@gmail.com>
Date: Wed, 21 Jul 2021 21:18:04 +0300
Subject: [PATCH] List and allow to query EGL extensions on Windows.

---
 ui/gl/gl_detection.cpp | 28 ++++++++++++++++++++++++++++
 ui/gl/gl_detection.h   |  3 +++
 2 files changed, 31 insertions(+)

diff --git a/ui/gl/gl_detection.cpp b/ui/gl/gl_detection.cpp
index 5973083..7b3f851 100644
--- a/ui/gl/gl_detection.cpp
+++ b/ui/gl/gl_detection.cpp
@@ -17,6 +17,12 @@
 #include <QtGui/QOpenGLFunctions>
 #include <QtWidgets/QOpenGLWidget>
 
+#ifdef Q_OS_WIN
+#include <QtGui/QGuiApplication>
+#include <qpa/qplatformnativeinterface.h>
+#include <EGL/egl.h>
+#endif // Q_OS_WIN
+
 #define LOG_ONCE(x) [[maybe_unused]] static auto logged = [&] { LOG(x); return true; }();
 
 namespace Ui::GL {
@@ -142,6 +148,15 @@ Capabilities CheckCapabilities(QWidget *widget) {
 			list.append(QString::fromLatin1(extension));
 		}
 		LOG(("OpenGL Extensions: %1").arg(list.join(", ")));
+
+#ifdef Q_OS_WIN
+		auto egllist = QStringList();
+		for (const auto &extension : EGLExtensions(context)) {
+			egllist.append(QString::fromLatin1(extension));
+		}
+		LOG(("EGL Extensions: %1").arg(egllist.join(", ")));
+#endif // Q_OS_WIN
+
 		return true;
 	}();
 
@@ -225,6 +240,19 @@ ANGLE CurrentANGLE() {
 	return ResolvedANGLE;
 }
 
+QList<QByteArray> EGLExtensions(not_null<QOpenGLContext*> context) {
+	const auto native = QGuiApplication::platformNativeInterface();
+	Assert(native != nullptr);
+
+	const auto display = static_cast<EGLDisplay>(
+		native->nativeResourceForContext(
+			QByteArrayLiteral("egldisplay"),
+			context));
+	return display
+		? QByteArray(eglQueryString(display, EGL_EXTENSIONS)).split(' ')
+		: QList<QByteArray>();
+}
+
 #endif // Q_OS_WIN
 
 } // namespace Ui::GL
diff --git a/ui/gl/gl_detection.h b/ui/gl/gl_detection.h
index c50cab7..6c1ef91 100644
--- a/ui/gl/gl_detection.h
+++ b/ui/gl/gl_detection.h
@@ -40,4 +40,7 @@ void ConfigureANGLE(); // Requires Ui::Integration being set.
 void ChangeANGLE(ANGLE backend);
 [[nodiscard]] ANGLE CurrentANGLE();
 
+[[nodiscard]] QList<QByteArray> EGLExtensions(
+	not_null<QOpenGLContext*> context);
+
 } // namespace Ui::GL