From 882d57326c39a0268587c75009a45ffeeb14b36f Mon Sep 17 00:00:00 2001
From: Mustafa Quraish <mustafaq9@gmail.com>
Date: Thu, 2 Sep 2021 17:50:06 -0400
Subject: LibGfx/Color: Use luminosity to compute grayscale value

Issue #9758 discusses this.
---
 Userland/Libraries/LibGfx/Color.h | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

(limited to 'Userland/Libraries')

diff --git a/Userland/Libraries/LibGfx/Color.h b/Userland/Libraries/LibGfx/Color.h
index ab459e6284..ba9d52feec 100644
--- a/Userland/Libraries/LibGfx/Color.h
+++ b/Userland/Libraries/LibGfx/Color.h
@@ -221,9 +221,14 @@ public:
             alpha() * other.alpha() / 255);
     }
 
+    constexpr u8 luminosity() const
+    {
+        return (red() * 0.2126f + green() * 0.7152f + blue() * 0.0722f);
+    }
+
     constexpr Color to_grayscale() const
     {
-        int gray = (red() + green() + blue()) / 3;
+        auto gray = luminosity();
         return Color(gray, gray, gray, alpha());
     }
 
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