diff --git a/CMakeLists.txt b/CMakeLists.txt
index dd9ceba..1f9a6cf 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -261,6 +261,7 @@ PRIVATE
     ui/abstract_button.h
     ui/animated_icon.cpp
     ui/animated_icon.h
+    ui/arc_angles.h
     ui/basic_click_handlers.cpp
     ui/basic_click_handlers.h
     ui/cached_special_layer_shadow_corners.cpp
diff --git a/ui/arc_angles.h b/ui/arc_angles.h
new file mode 100644
index 0000000..39c1ce2
--- /dev/null
+++ b/ui/arc_angles.h
@@ -0,0 +1,18 @@
+/*
+This file is part of Telegram Desktop,
+the official desktop application for the Telegram messaging service.
+
+For license and copyright information please follow this link:
+https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
+*/
+#pragma once
+
+namespace arc {
+
+constexpr auto kFullLength = 360 * 16;
+constexpr auto kHalfLength = (kFullLength / 2);
+constexpr auto kQuarterLength = (kFullLength / 4);
+constexpr auto kMinLength = (kFullLength / 360);
+constexpr auto kAlmostFullLength = (kFullLength - kMinLength);
+
+} // namespace arc
diff --git a/ui/effects/cross_animation.cpp b/ui/effects/cross_animation.cpp
index 18a9cd4..e847ab3 100644
--- a/ui/effects/cross_animation.cpp
+++ b/ui/effects/cross_animation.cpp
@@ -7,6 +7,7 @@
 #include "ui/effects/cross_animation.h"
 
 #include "ui/effects/animation_value.h"
+#include "ui/arc_angles.h"
 #include "ui/painter.h"
 
 #include <QtCore/QtMath>
@@ -17,7 +18,6 @@ namespace {
 
 constexpr auto kPointCount = 12;
 constexpr auto kStaticLoadingValue = float64(-666);
-constexpr auto kFullArcLength = 360 * 16;
 
 
 //
@@ -148,12 +148,12 @@ void CrossAnimation::paint(
 	auto pathDeleteSize = kPointCount;
 
 	const auto staticLoading = (loading == kStaticLoadingValue);
-	auto loadingArcLength = staticLoading ? kFullArcLength : 0;
+	auto loadingArcLength = staticLoading ? arc::kFullLength : 0;
 	if (loading > 0.) {
 		transformLoadingCross(loading, pathDelete, pathDeleteSize);
 
 		auto loadingArc = (loading >= 0.5) ? (loading - 1.) : loading;
-		loadingArcLength = qRound(-loadingArc * 2 * kFullArcLength);
+		loadingArcLength = qRound(-loadingArc * 2 * arc::kFullLength);
 	}
 
 	if (!staticLoading) {
@@ -184,9 +184,9 @@ void CrossAnimation::paint(
 		if (staticLoading) {
 			anim::DrawStaticLoading(p, roundPart, stroke, color);
 		} else {
-			auto loadingArcStart = kFullArcLength / 8;
+			auto loadingArcStart = arc::kQuarterLength / 2;
 			if (shown < 1.) {
-				loadingArcStart -= qRound(-(shown - 1.) * kFullArcLength / 4.);
+				loadingArcStart -= qRound(-(shown - 1.) * arc::kQuarterLength);
 			}
 			if (loadingArcLength < 0) {
 				loadingArcStart += loadingArcLength;
diff --git a/ui/effects/radial_animation.cpp b/ui/effects/radial_animation.cpp
index 2ae1d53..8de21b6 100644
--- a/ui/effects/radial_animation.cpp
+++ b/ui/effects/radial_animation.cpp
@@ -6,16 +6,14 @@
 //
 #include "ui/effects/radial_animation.h"
 
+#include "ui/arc_angles.h"
 #include "ui/painter.h"
 #include "styles/style_widgets.h"
 
 namespace Ui {
 namespace {
 
-constexpr auto kFullArcLength = 360 * 16;
-constexpr auto kQuarterArcLength = (kFullArcLength / 4);
-constexpr auto kMinArcLength = (kFullArcLength / 360);
-constexpr auto kAlmostFullArcLength = (kFullArcLength - kMinArcLength);
+constexpr auto kFullArcLength = arc::kFullLength;
 
 } // namespace
 
@@ -23,14 +21,14 @@ const int RadialState::kFull = kFullArcLength;
 
 void RadialAnimation::start(float64 prg) {
 	_firstStart = _lastStart = _lastTime = crl::now();
-	const auto iprg = qRound(qMax(prg, 0.0001) * kAlmostFullArcLength);
-	const auto iprgstrict = qRound(prg * kAlmostFullArcLength);
+	const auto iprg = qRound(qMax(prg, 0.0001) * arc::kAlmostFullLength);
+	const auto iprgstrict = qRound(prg * arc::kAlmostFullLength);
 	_arcEnd = anim::value(iprgstrict, iprg);
 	_animation.start();
 }
 
 bool RadialAnimation::update(float64 prg, bool finished, crl::time ms) {
-	const auto iprg = qRound(qMax(prg, 0.0001) * kAlmostFullArcLength);
+	const auto iprg = qRound(qMax(prg, 0.0001) * arc::kAlmostFullLength);
 	const auto result = (iprg != qRound(_arcEnd.to()))
 		|| (_finished != finished);
 	if (_finished != finished) {
@@ -101,13 +99,13 @@ void RadialAnimation::draw(
 }
 
 RadialState RadialAnimation::computeState() const {
-	auto length = kMinArcLength + qRound(_arcEnd.current());
-	auto from = kQuarterArcLength
+	auto length = arc::kMinLength + qRound(_arcEnd.current());
+	auto from = arc::kQuarterLength
 		- length
 		- (anim::Disabled() ? 0 : qRound(_arcStart.current()));
 	if (style::RightToLeft()) {
-		from = kQuarterArcLength - (from - kQuarterArcLength) - length;
-		if (from < 0) from += kFullArcLength;
+		from = arc::kQuarterLength - (from - arc::kQuarterLength) - length;
+		if (from < 0) from += arc::kFullLength;
 	}
 	return { _opacity, from, length };
 }