From 93957145376d0b7c91ec22f28f9e0b29c527afac Mon Sep 17 00:00:00 2001
From: Ilya Fedin <fedin-ilja2010@ya.ru>
Date: Sat, 8 Apr 2023 09:54:15 +0400
Subject: [PATCH] Avoid event loop being throttled by OpenGL

By default, Qt uses swap interval of 1 what causes the (egl|wgl|glx)SwapBuffers call to wait for vblank. Using swap interval of 0 makes the call to return immediately.
---
 ui/rp_widget.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/ui/rp_widget.cpp b/ui/rp_widget.cpp
index afa77b9..35fbe2f 100644
--- a/ui/rp_widget.cpp
+++ b/ui/rp_widget.cpp
@@ -44,6 +44,12 @@ public:
 
 TWidget::TWidget(QWidget *parent)
 : TWidgetHelper<QWidget>(*(new TWidgetPrivate), parent, {}) {
+	[[maybe_unused]] static const auto Once = [] {
+		auto format = QSurfaceFormat::defaultFormat();
+		format.setSwapInterval(0);
+		QSurfaceFormat::setDefaultFormat(format);
+		return true;
+	}();
 }
 
 namespace Ui {