Merge branch 'MoonPhaseAndVisibilityFixes' into 'master'

Match vanilla moon phases and visibility times

Closes #8375

See merge request OpenMW/openmw!4616

apps/openmw/mwworld/weather.cpp

@@ -352,6 +352,30 @@ namespace MWWorld
         mWeather = 0;
     }
 
+    MoonModel::MoonModel(float fadeInStart, float fadeInFinish, float fadeOutStart, float fadeOutFinish,
+        float axisOffset, float speed, float dailyIncrement, float fadeStartAngle, float fadeEndAngle,
+        float moonShadowEarlyFadeAngle)
+    {
+        mFadeInStart = fadeInStart;
+        mFadeInFinish = fadeInFinish;
+        mFadeOutStart = fadeOutStart;
+        mFadeOutFinish = fadeOutFinish;
+        mAxisOffset = axisOffset;
+        mDailyIncrement = dailyIncrement;
+        mFadeStartAngle = fadeStartAngle;
+        mFadeEndAngle = fadeEndAngle;
+        mMoonShadowEarlyFadeAngle = moonShadowEarlyFadeAngle;
+
+        // Morrowind appears to have a minimum speed to avoid situations where the moon can't
+        // complete a full rotation in a single 24-hour period. The reverse-engineered formula is
+        // 180 degrees (full hemisphere) / 23 hours / 15 degrees (1 hour travel at speed 1.0).
+        mSpeed = std::max(speed, (180.0f / 23.0f / 15.0f));
+
+        // Morrowind appears to reduce mDailyIncrement with modulo 24.0f to avoid situations where
+        // the moon would increment more than an entire rotation in a single day.
+        mDailyIncrement = std::fmod(mDailyIncrement, 24.0f);
+    }
+
     MoonModel::MoonModel(const std::string& name)
         : mFadeInStart(Fallback::Map::getFloat("Moons_" + name + "_Fade_In_Start"))
         , mFadeInFinish(Fallback::Map::getFloat("Moons_" + name + "_Fade_In_Finish"))
@@ -364,14 +388,19 @@ namespace MWWorld
         , mFadeEndAngle(Fallback::Map::getFloat("Moons_" + name + "_Fade_End_Angle"))
         , mMoonShadowEarlyFadeAngle(Fallback::Map::getFloat("Moons_" + name + "_Moon_Shadow_Early_Fade_Angle"))
     {
-        // Morrowind appears to have a minimum speed in order to avoid situations where the moon couldn't conceivably
-        // complete a rotation in a single 24 hour period. The value of 180/23 was deduced from reverse engineering.
-        mSpeed = std::min(mSpeed, 180.0f / 23.0f);
+        // Morrowind appears to have a minimum speed to avoid situations where the moon can't
+        // complete a full rotation in a single 24-hour period. The reverse-engineered formula is
+        // 180 degrees (full hemisphere) / 23 hours / 15 degrees (1 hour travel at speed 1.0).
+        mSpeed = std::max(mSpeed, (180.0f / 23.0f / 15.0f));
+
+        // Morrowind appears to reduce mDailyIncrement with modulo 24.0f to avoid situations where
+        // the moon would increment more than an entire rotation in a single day.
+        mDailyIncrement = std::fmod(mDailyIncrement, 24.0f);
     }
 
     MWRender::MoonState MoonModel::calculateState(const TimeStamp& gameTime) const
     {
-        float rotationFromHorizon = angle(gameTime);
+        float rotationFromHorizon = angle(gameTime.getDay(), gameTime.getHour());
         MWRender::MoonState state = { rotationFromHorizon,
             mAxisOffset, // Reverse engineered from Morrowind's scene graph rotation matrices.
             phase(gameTime), shadowBlend(rotationFromHorizon),
@@ -380,7 +409,7 @@ namespace MWWorld
         return state;
     }
 
-    inline float MoonModel::angle(const TimeStamp& gameTime) const
+    inline float MoonModel::angle(int gameDay, float gameHour) const
     {
         // Morrowind's moons start travel on one side of the horizon (let's call it H-rise) and travel 180 degrees to
         // the opposite horizon (let's call it H-set). Upon reaching H-set, they reset to H-rise until the next moon
@@ -390,49 +419,83 @@ namespace MWWorld
         // 1. Moon rises and then sets in one day.
         // 2. Moon sets and doesn't rise in one day (occurs when the moon rise hour is >= 24).
         // 3. Moon sets and then rises in one day.
-        float moonRiseHourToday = moonRiseHour(gameTime.getDay());
-        float moonRiseAngleToday = 0;
+        float moonRiseHourToday = moonRiseHour(gameDay);
+        float moonRiseAngleToday = 0.0f;
 
-        if (gameTime.getHour() < moonRiseHourToday)
+        if (gameHour < moonRiseHourToday)
         {
-            float moonRiseHourYesterday = moonRiseHour(gameTime.getDay() - 1);
-            if (moonRiseHourYesterday < 24)
+            // Rise hour increases by mDailyIncrement each day, so yesterday's is easy to calculate
+            float moonRiseHourYesterday = moonRiseHourToday - mDailyIncrement;
+            if (moonRiseHourYesterday < 24.0f)
             {
-                float moonRiseAngleYesterday = rotation(24 - moonRiseHourYesterday);
-                if (moonRiseAngleYesterday < 180)
+                // Morrowind offsets the increment by -1 when the previous day's visible point crosses into the next
+                // day. The offset lasts from this point until the next 24-day loop starts. To find this point we add
+                // mDailyIncrement to the previous visible point and check the result.
+                float moonShadowEarlyFadeAngle1 = mFadeEndAngle - mMoonShadowEarlyFadeAngle;
+                float timeToVisible = moonShadowEarlyFadeAngle1 / rotation(1.0f);
+                float cycleOffset = moonRiseHourYesterday + timeToVisible > 24.0f ? mDailyIncrement : 0.0f;
+
+                float moonRiseAngleYesterday = rotation(24.0f - (moonRiseHourYesterday + cycleOffset));
+                if (moonRiseAngleYesterday < 180.0f)
                 {
                     // The moon rose but did not set yesterday, so accumulate yesterday's angle with how much we've
                     // travelled today.
-                    moonRiseAngleToday = rotation(gameTime.getHour()) + moonRiseAngleYesterday;
+                    moonRiseAngleToday = rotation(gameHour) + moonRiseAngleYesterday;
                 }
             }
         }
         else
         {
-            moonRiseAngleToday = rotation(gameTime.getHour() - moonRiseHourToday);
+            moonRiseAngleToday = rotation(gameHour - moonRiseHourToday);
         }
 
-        if (moonRiseAngleToday >= 180)
+        if (moonRiseAngleToday >= 180.0f)
         {
             // The moon set today, reset the angle to the horizon.
-            moonRiseAngleToday = 0;
+            moonRiseAngleToday = 0.0f;
         }
 
         return moonRiseAngleToday;
     }
 
-    inline float MoonModel::moonRiseHour(unsigned int daysPassed) const
+    inline float MoonModel::moonPhaseHour(int gameDay) const
     {
+        // Morrowind delays moon phase changes until one of these is true:
+        //   * The moon is invisible at midnight.
+        //   * The moon reached moonShadowEarlyFadeAngle2 one daily increment ago (therefore invisible).
+        if (!isVisible(gameDay, 0.0f))
+            return 0.0f;
+        else
+        {
+            // Calculate the angle at which the moon becomes transparent and the starting angle.
+            float moonShadowEarlyFadeAngle2 = (180.0f - mFadeEndAngle) + mMoonShadowEarlyFadeAngle;
+            float midnightAngle = angle(gameDay, 0.0f);
+
+            // We can assume that moonShadowEarlyFadeAngle2 > midnightAngle, because the opposite
+            // case would make the moon invisible at midnight, which is checked above.
+            return ((moonShadowEarlyFadeAngle2 - midnightAngle) / rotation(1.0f)) + std::max(mDailyIncrement, 0.0f);
+        }
+    }
+
+    inline float MoonModel::moonRiseHour(int gameDay) const
+    {
+        if (mDailyIncrement == 0.0f)
+            return 0.0f;
+
         // This arises from the start date of 16 Last Seed, 427
         // TODO: Find an alternate formula that doesn't rely on this day being fixed.
-        static const unsigned int startDay = 16;
+        constexpr int startDay = 16;
+
+        // This formula finds the number of missed increments necessary to make the rise hour a 24-day loop.
+        // The offset increases on the first day of the loop and is multiplied by the number of completed loops.
+        float incrementOffset = (24.0f - std::abs(24.0f / mDailyIncrement)) * std::floor((gameDay + startDay) / 24.0f);
 
         // This odd formula arises from the fact that on 16 Last Seed, 17 increments have occurred, meaning
         // that upon starting a new game, it must only calculate the moon phase as far back as 1 Last Seed.
         // Note that we don't modulo after adding the latest daily increment because other calculations need to
         // know if doing so would cause the moon rise to be postponed until the next day (which happens when
         // the moon rise hour is >= 24 in Morrowind).
-        return mDailyIncrement + std::fmod((daysPassed - 1 + startDay) * mDailyIncrement, 24.0f);
+        return mDailyIncrement + std::fmod((gameDay - 1 + startDay - incrementOffset) * mDailyIncrement, 24.0f);
     }
 
     inline float MoonModel::rotation(float hours) const
@@ -449,12 +512,18 @@ namespace MWWorld
         // phase cycle.
 
         // If the moon didn't rise yet today, use yesterday's moon phase.
-        if (gameTime.getHour() < moonRiseHour(gameTime.getDay()))
+        if (gameTime.getHour() < moonPhaseHour(gameTime.getDay()))
             return static_cast<MWRender::MoonState::Phase>((gameTime.getDay() / 3) % 8);
         else
             return static_cast<MWRender::MoonState::Phase>(((gameTime.getDay() + 1) / 3) % 8);
     }
 
+    inline bool MoonModel::isVisible(int gameDay, float gameHour) const
+    {
+        // Moons are "visible" when their alpha value is non-zero.
+        return hourlyAlpha(gameHour) > 0.f && earlyMoonShadowAlpha(angle(gameDay, gameHour)) > 0.f;
+    }
+
     inline float MoonModel::shadowBlend(float angle) const
     {
         // The Fade End Angle and Fade Start Angle describe a region where the moon transitions from a solid disk
@@ -480,6 +549,10 @@ namespace MWWorld
 
     inline float MoonModel::hourlyAlpha(float gameHour) const
     {
+        // Morrowind culls the moon one minute before mFadeOutFinish
+        constexpr float oneMinute = 0.0167f;
+        float adjustedFadeOutFinish = mFadeOutFinish - oneMinute;
+
         // The Fade Out Start / Finish and Fade In Start / Finish describe the hours at which the moon
         // appears and disappears.
         // Depending on the current hour, the following values describe how transparent the moon is.
@@ -487,9 +560,9 @@ namespace MWWorld
         // 2. From Fade Out Finish to Fade In Start: 0 (transparent)
         // 3. From Fade In Start to Fade In Finish: 0..1
         // 4. From Fade In Finish to Fade Out Start: 1 (solid)
-        if ((gameHour >= mFadeOutStart) && (gameHour < mFadeOutFinish))
-            return (mFadeOutFinish - gameHour) / (mFadeOutFinish - mFadeOutStart);
-        else if ((gameHour >= mFadeOutFinish) && (gameHour < mFadeInStart))
+        if ((gameHour >= mFadeOutStart) && (gameHour < adjustedFadeOutFinish))
+            return (adjustedFadeOutFinish - gameHour) / (adjustedFadeOutFinish - mFadeOutStart);
+        else if ((gameHour >= adjustedFadeOutFinish) && (gameHour < mFadeInStart))
             return 0.0f;
         else if ((gameHour >= mFadeInStart) && (gameHour < mFadeInFinish))
             return (gameHour - mFadeInStart) / (mFadeInFinish - mFadeInStart);

apps/openmw/mwworld/weather.hpp

@@ -251,6 +251,9 @@ namespace MWWorld
     {
     public:
         MoonModel(const std::string& name);
+        MoonModel(float fadeInStart, float fadeInFinish, float fadeOutStart, float fadeOutFinish, float axisOffset,
+            float speed, float dailyIncrement, float fadeStartAngle, float fadeEndAngle,
+            float moonShadowEarlyFadeAngle);
 
         MWRender::MoonState calculateState(const TimeStamp& gameTime) const;
 
@@ -266,10 +269,12 @@ namespace MWWorld
         float mFadeEndAngle;
         float mMoonShadowEarlyFadeAngle;
 
-        float angle(const TimeStamp& gameTime) const;
-        float moonRiseHour(unsigned int daysPassed) const;
+        float angle(int gameDay, float gameHour) const;
+        float moonPhaseHour(int gameDay) const;
+        float moonRiseHour(int gameDay) const;
         float rotation(float hours) const;
         MWRender::MoonState::Phase phase(const TimeStamp& gameTime) const;
+        bool isVisible(int gameDay, float gameHour) const;
         float shadowBlend(float angle) const;
         float hourlyAlpha(float gameHour) const;
         float earlyMoonShadowAlpha(float angle) const;

apps/openmw_tests/CMakeLists.txt

@@ -10,6 +10,7 @@ file(GLOB UNITTEST_SRC_FILES
     mwworld/testduration.cpp
     mwworld/testtimestamp.cpp
     mwworld/testptr.cpp
+    mwworld/testweather.cpp
 
     mwdialogue/test_keywordsearch.cpp
 

apps/openmw_tests/mwworld/testweather.cpp

@@ -0,0 +1,732 @@
+#include <gtest/gtest.h>
+
+#include <cmath>
+
+#include "apps/openmw/mwworld/timestamp.hpp"
+#include "apps/openmw/mwworld/weather.hpp"
+
+namespace MWWorld
+{
+    namespace
+    {
+        // MASSER PHASES
+
+        TEST(MWWorldWeatherTest, masserPhasesFullToWaningGibbousAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 2 and 26, 11:57
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 2 + 11.0f + 56.0f / 60.0f);
+            timeStampAfter += (24.0f * 2 + 11.0f + 58.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 26 + 11.0f + 56.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 26 + 11.0f + 58.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesWaningGibbousToThirdQuarterAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 5 and 29, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 4 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 5 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 28 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 29 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesThirdQuarterToWaningCrescentAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 8 and 32, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 7 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 8 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 31 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 32 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesWaningCrescentToNewAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 11 and 35, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 10 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 11 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 34 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 35 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesNewToWaxingCrescentAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 14 and 38, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 13 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 14 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 37 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 38 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesWaxingCrescentToFirstQuarterAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 17 and 41, 2:57
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 17 + 2.0f + 56.0f / 60.0f);
+            timeStampAfter += (24.0f * 17 + 2.0f + 58.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 41 + 2.0f + 56.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 41 + 2.0f + 58.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesFirstQuarterToWaxingGibbousAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 20 and 44, 5:57
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 20 + 5.0f + 56.0f / 60.0f);
+            timeStampAfter += (24.0f * 20 + 5.0f + 58.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 44 + 5.0f + 56.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 44 + 5.0f + 58.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+        }
+
+        TEST(MWWorldWeatherTest, masserPhasesWaxingGibbousToFullAtCorrectTimes)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 35.0f;
+
+            // Days 23 and 47, 8:57
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 23 + 8.0f + 56.0f / 60.0f);
+            timeStampAfter += (24.0f * 23 + 8.0f + 58.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 47 + 8.0f + 56.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 47 + 8.0f + 58.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+        }
+
+        // SECUNDA PHASES
+
+        TEST(MWWorldWeatherTest, secundaPhasesFullToWaningGibbousAtCorrectTimes)
+        {
+            float dailyIncrement = 1.2f;
+            float speed = 0.6f;
+            float fadeEndAngle = 30.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 50.0f;
+
+            // Days 2 and 26, 14:19
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 2 + 14.0f + 18.0f / 60.0f);
+            timeStampAfter += (24.0f * 2 + 14.0f + 20.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 26 + 14.0f + 18.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 26 + 14.0f + 20.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+        }
+
+        TEST(MWWorldWeatherTest, secundaPhasesWaningGibbousToThirdQuarterAtCorrectTimes)
+        {
+            float dailyIncrement = 1.2f;
+            float speed = 0.6f;
+            float fadeEndAngle = 30.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 50.0f;
+
+            // Days 5 and 29, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 4 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 5 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 28 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 29 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(1));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+        }
+
+        TEST(MWWorldWeatherTest, secundaPhasesThirdQuarterToWaningCrescentAtCorrectTimes)
+        {
+            float dailyIncrement = 1.2f;
+            float speed = 0.6f;
+            float fadeEndAngle = 30.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 50.0f;
+
+            // Days 8 and 32, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 7 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 8 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 31 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 32 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(2));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+        }
+
+        TEST(MWWorldWeatherTest, secundaPhasesWaningCrescentToNewAtCorrectTimes)
+        {
+            float dailyIncrement = 1.2f;
+            float speed = 0.6f;
+            float fadeEndAngle = 30.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 50.0f;
+
+            // Days 11 and 35, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 10 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 11 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 34 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 35 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(3));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+        }
+
+        TEST(MWWorldWeatherTest, secundaPhasesNewToWaxingCrescentAtCorrectTimes)
+        {
+            float dailyIncrement = 1.2f;
+            float speed = 0.6f;
+            float fadeEndAngle = 30.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 50.0f;
+
+            // Days 14 and 38, 0:00
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 13 + 23.0f + 59.0f / 60.0f);
+            timeStampAfter += (24.0f * 14 + 0.0f + 1.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 37 + 23.0f + 59.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 38 + 0.0f + 1.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(4));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+        }
+
+        TEST(MWWorldWeatherTest, secundaPhasesWaxingCrescentToFirstQuarterAtCorrectTimes)
+        {
+            float dailyIncrement = 1.2f;
+            float speed = 0.6f;
+            float fadeEndAngle = 30.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 50.0f;
+
+            // Days 17 and 41, 3:31
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 17 + 3.0f + 30.0f / 60.0f);
+            timeStampAfter += (24.0f * 17 + 3.0f + 32.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 41 + 3.0f + 30.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 41 + 3.0f + 32.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(5));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+        }
+
+        TEST(MWWorldWeatherTest, secundaPhasesFirstQuarterToWaxingGibbousAtCorrectTimes)
+        {
+            float dailyIncrement = 1.2f;
+            float speed = 0.6f;
+            float fadeEndAngle = 30.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 50.0f;
+
+            // Days 20 and 44, 7:07
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 20 + 7.0f + 6.0f / 60.0f);
+            timeStampAfter += (24.0f * 20 + 7.0f + 8.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 44 + 7.0f + 6.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 44 + 7.0f + 8.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(6));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+        }
+
+        TEST(MWWorldWeatherTest, secundaPhasesWaxingGibbousToFullAtCorrectTimes)
+        {
+            float dailyIncrement = 1.2f;
+            float speed = 0.6f;
+            float fadeEndAngle = 30.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 50.0f;
+
+            // Days 23 and 47, 10:43
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 23 + 10.0f + 42.0f / 60.0f);
+            timeStampAfter += (24.0f * 23 + 10.0f + 44.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 47 + 10.0f + 42.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 47 + 10.0f + 44.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_EQ(beforeState.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+            EXPECT_EQ(afterState.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+            EXPECT_EQ(beforeStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(7));
+            EXPECT_EQ(afterStatePostLoop.mPhase, static_cast<MWRender::MoonState::Phase>(0));
+        }
+
+        // OFFSETS
+
+        TEST(MWWorldWeatherTest, secundaShouldApplyIncrementOffsetAfterFirstLoop)
+        {
+            float dailyIncrement = 1.2f;
+            float speed = 0.6f;
+            float fadeEndAngle = 30.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 14.0f;
+            float fadeInFinish = 15.0f;
+            float fadeOutStart = 7.0f;
+            float fadeOutFinish = 10.0f;
+            float axisOffset = 50.0f;
+
+            // Days 8 and 32, 3:16
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 8 + 3.0f + 15.0f / 60.0f);
+            timeStampAfter += (24.0f * 8 + 3.0f + 17.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 32 + 3.0f + 15.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 32 + 3.0f + 17.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_LE(beforeState.mMoonAlpha, 0.0f);
+            EXPECT_GT(afterState.mMoonAlpha, 0.0f);
+            EXPECT_LE(beforeStatePostLoop.mMoonAlpha, 0.0f);
+            EXPECT_GT(afterStatePostLoop.mMoonAlpha, 0.0f);
+        }
+
+        TEST(MWWorldWeatherTest, moonWithLowIncrementShouldApplyIncrementOffsetAfterCycle)
+        {
+            float dailyIncrement = 0.9f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 0.0f;
+            float fadeInFinish = 0.0f;
+            float fadeOutStart = 0.0f;
+            float fadeOutFinish = 0.0f;
+            float axisOffset = 35.0f;
+
+            // Days 7 and 31, 1:44
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 7 + 1.0f + 43.0f / 60.0f);
+            timeStampAfter += (24.0f * 7 + 1.0f + 45.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 31 + 1.0f + 43.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 31 + 1.0f + 45.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_LE(beforeState.mMoonAlpha, 0.0f);
+            EXPECT_GT(afterState.mMoonAlpha, 0.0f);
+            EXPECT_LE(beforeStatePostLoop.mMoonAlpha, 0.0f);
+            EXPECT_GT(afterStatePostLoop.mMoonAlpha, 0.0f);
+        }
+
+        TEST(MWWorldWeatherTest, masserShouldApplyIncrementOffsetAfterCycle)
+        {
+            float dailyIncrement = 1.0f;
+            float speed = 0.5f;
+            float fadeEndAngle = 40.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 0.0f;
+            float fadeInFinish = 0.0f;
+            float fadeOutStart = 0.0f;
+            float fadeOutFinish = 0.0f;
+            float axisOffset = 35.0f;
+
+            // Days 4 and 28, 1:02
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 4 + 1.0f + 1.0f / 60.0f);
+            timeStampAfter += (24.0f * 4 + 1.0f + 3.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 28 + 1.0f + 1.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 28 + 1.0f + 3.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_LE(beforeState.mMoonAlpha, 0.0f);
+            EXPECT_GT(afterState.mMoonAlpha, 0.0f);
+            EXPECT_LE(beforeStatePostLoop.mMoonAlpha, 0.0f);
+            EXPECT_GT(afterStatePostLoop.mMoonAlpha, 0.0f);
+        }
+
+        TEST(MWWorldWeatherTest, secundaShouldApplyIncrementOffsetAfterCycle)
+        {
+            float dailyIncrement = 1.2f;
+            float speed = 0.6f;
+            float fadeEndAngle = 30.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 0.0f;
+            float fadeInFinish = 0.0f;
+            float fadeOutStart = 0.0f;
+            float fadeOutFinish = 0.0f;
+            float axisOffset = 50.0f;
+
+            // Days 3 and 27, 2:04
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 3 + 2.0f + 3.0f / 60.0f);
+            timeStampAfter += (24.0f * 3 + 2.0f + 5.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 27 + 2.0f + 3.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 27 + 2.0f + 5.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_LE(beforeState.mMoonAlpha, 0.0f);
+            EXPECT_GT(afterState.mMoonAlpha, 0.0f);
+            EXPECT_LE(beforeStatePostLoop.mMoonAlpha, 0.0f);
+            EXPECT_GT(afterStatePostLoop.mMoonAlpha, 0.0f);
+        }
+
+        TEST(MWWorldWeatherTest, moonWithIncreasedSpeedShouldApplyIncrementOffsetAfterCycle)
+        {
+            float dailyIncrement = 1.2f;
+            float speed = 1.6f;
+            float fadeEndAngle = 30.0f;
+            float fadeStartAngle = 50.0f;
+            float moonShadowEarlyFadeAngle = 0.5f;
+            float fadeInStart = 0.0f;
+            float fadeInFinish = 0.0f;
+            float fadeOutStart = 0.0f;
+            float fadeOutFinish = 0.0f;
+            float axisOffset = 50.0f;
+
+            // Days 4 and 28, 1:13
+            TimeStamp timeStampBefore, timeStampAfter, timeStampBeforePostLoop, timeStampAfterPostLoop;
+            timeStampBefore += (24.0f * 4 + 1.0f + 12.0f / 60.0f);
+            timeStampAfter += (24.0f * 4 + 1.0f + 14.0f / 60.0f);
+            timeStampBeforePostLoop += (24.0f * 28 + 1.0f + 12.0f / 60.0f);
+            timeStampAfterPostLoop += (24.0f * 28 + 1.0f + 14.0f / 60.0f);
+
+            MWWorld::MoonModel moon = MWWorld::MoonModel(fadeInStart, fadeInFinish, fadeOutStart, fadeOutFinish,
+                axisOffset, speed, dailyIncrement, fadeStartAngle, fadeEndAngle, moonShadowEarlyFadeAngle);
+
+            MWRender::MoonState beforeState = moon.calculateState(timeStampBefore);
+            MWRender::MoonState afterState = moon.calculateState(timeStampAfter);
+            MWRender::MoonState beforeStatePostLoop = moon.calculateState(timeStampBeforePostLoop);
+            MWRender::MoonState afterStatePostLoop = moon.calculateState(timeStampAfterPostLoop);
+
+            EXPECT_LE(beforeState.mMoonAlpha, 0.0f);
+            EXPECT_GT(afterState.mMoonAlpha, 0.0f);
+            EXPECT_LE(beforeStatePostLoop.mMoonAlpha, 0.0f);
+            EXPECT_GT(afterStatePostLoop.mMoonAlpha, 0.0f);
+        }
+    }
+}