https://bugs.gentoo.org/961871
https://github.com/OGRECave/ogre/issues/3431
https://github.com/OGRECave/ogre/pull/3434

From 2130758685a58b963ee1012e0bf0ef50859d38f5 Mon Sep 17 00:00:00 2001
From: Pavel Rojtberg <rojtberg@gmail.com>
Date: Sat, 23 Aug 2025 01:36:01 +0200
Subject: [PATCH] Main: Bitwise - do not generate nan for bits=0

---
 OgreMain/include/OgreBitwise.h      | 2 +-
 Tests/OgreMain/src/BitwiseTests.cpp | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/OgreMain/include/OgreBitwise.h b/OgreMain/include/OgreBitwise.h
index 3ce2115546b..ab321cfc5fb 100644
--- a/OgreMain/include/OgreBitwise.h
+++ b/OgreMain/include/OgreBitwise.h
@@ -246,7 +246,7 @@ namespace Ogre {
          */
         static inline float fixedToFloat(unsigned value, unsigned int bits)
         {
-            return (float)value/(float)((1<<bits)-1);
+            return bits ? (float)value/(float)((1<<bits)-1) : 0.0f;
         }
 
         /**
diff --git a/Tests/OgreMain/src/BitwiseTests.cpp b/Tests/OgreMain/src/BitwiseTests.cpp
index 2d482795904..3afb4e86acb 100644
--- a/Tests/OgreMain/src/BitwiseTests.cpp
+++ b/Tests/OgreMain/src/BitwiseTests.cpp
@@ -46,6 +46,7 @@ TEST(BitwiseTests,FixedPointConversion)
 
     EXPECT_EQ(Bitwise::fixedToFloat(0xFF, 8), 1.0f);
     EXPECT_EQ(Bitwise::fixedToFloat(0x00, 8), 0.0f);
+    EXPECT_EQ(Bitwise::fixedToFloat(0xFF, 0), 0.0f);
 
     EXPECT_EQ(Bitwise::floatToFixed(1.0f, 8), (unsigned int)0xFF);
     EXPECT_EQ(Bitwise::floatToFixed(0.0f, 8), (unsigned int)0x00);