From 746eb80300f788e1c340f8d5b363a9eac94f7499 Mon Sep 17 00:00:00 2001
From: John Preston <johnprestonmail@gmail.com>
Date: Thu, 1 Sep 2022 11:23:16 +0400
Subject: [PATCH] Allow interface scale of 50%.

---
 ui/style/style_core_scale.cpp |  2 +-
 ui/style/style_core_scale.h   | 11 +++++++----
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/ui/style/style_core_scale.cpp b/ui/style/style_core_scale.cpp
index 2aefdc2..9e0038f 100644
--- a/ui/style/style_core_scale.cpp
+++ b/ui/style/style_core_scale.cpp
@@ -21,7 +21,7 @@ int DevicePixelRatio() {
 }
 
 void SetDevicePixelRatio(int ratio) {
-	DevicePixelRatioValue = ratio;
+	DevicePixelRatioValue = std::clamp(ratio, 1, kScaleMax / kScaleMin);
 }
 
 int Scale() {
diff --git a/ui/style/style_core_scale.h b/ui/style/style_core_scale.h
index 93ac4da..2fba205 100644
--- a/ui/style/style_core_scale.h
+++ b/ui/style/style_core_scale.h
@@ -16,7 +16,7 @@
 namespace style {
 
 inline constexpr auto kScaleAuto = 0;
-inline constexpr auto kScaleMin = 75;
+inline constexpr auto kScaleMin = 50;
 inline constexpr auto kScaleDefault = 100;
 inline constexpr auto kScaleMax = 300;
 
@@ -34,9 +34,12 @@ void SetScale(int scale);
 
 template <typename T>
 [[nodiscard]] inline T ConvertScale(T value, int scale) {
-	return (value < 0.)
-		? (-ConvertScale(-value, scale))
-		: T(base::SafeRound((double(value) * scale / 100.) - 0.01));
+	if (value < 0.) {
+		return -ConvertScale(-value, scale);
+	}
+	const auto result = T(base::SafeRound(
+		(double(value) * scale / 100.) - 0.01));
+	return (!std::is_integral_v<T> || !value || result) ? result : 1;
 }
 
 template <typename T>