From b2fab5f5adf4e00f33915419cb0a8fda4c2e805c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=CE=B6eh=20Matt?= <5415177+ZehMatt@users.noreply.github.com>
Date: Tue, 17 May 2022 17:40:58 +0300
Subject: [PATCH] Use World prng for weather system as it influences actors

---
 apps/openmw/mwworld/weather.cpp | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/apps/openmw/mwworld/weather.cpp b/apps/openmw/mwworld/weather.cpp
index eb0226d506..1e12d0b1dd 100644
--- a/apps/openmw/mwworld/weather.cpp
+++ b/apps/openmw/mwworld/weather.cpp
@@ -226,8 +226,8 @@ namespace MWWorld
             if(transitionRatio >= mThunderThreshold && mThunderFrequency > 0.0f)
             {
                 flashDecrement(elapsedSeconds);
-
-                if(Misc::Rng::rollProbability() <= thunderChance(transitionRatio, elapsedSeconds))
+                auto& prng = MWBase::Environment::get().getWorld()->getPrng();
+                if(Misc::Rng::rollProbability(prng) <= thunderChance(transitionRatio, elapsedSeconds))
                 {
                     lightningAndThunder();
                 }
@@ -265,7 +265,8 @@ namespace MWWorld
         // They appear to go from 0 (brightest, closest) to 3 (faintest, farthest). The value of 0.25 per distance
         // was derived by setting the Flash Decrement to 0.1 and measuring how long each value took to decay to 0.
         // TODO: Determine the distribution of each distance to see if it's evenly weighted.
-        unsigned int distance = Misc::Rng::rollDice(4);
+        auto& prng = MWBase::Environment::get().getWorld()->getPrng();
+        unsigned int distance = Misc::Rng::rollDice(4, prng);
         // Flash brightness appears additive, since if multiple strikes occur, it takes longer for it to decay to 0.
         mFlashBrightness += 1 - (distance * 0.25f);
         MWBase::Environment::get().getSoundManager()->playSound(mThunderSoundID[distance], 1.0, 1.0);
@@ -348,7 +349,8 @@ namespace MWWorld
         // All probabilities must add to 100 (responsibility of the user).
         // If chances A and B has values 30 and 70 then by generating 100 numbers 1..100, 30% will be lesser or equal 30
         // and 70% will be greater than 30 (in theory).
-        int chance = Misc::Rng::rollDice(100) + 1; // 1..100
+        auto& prng = MWBase::Environment::get().getWorld()->getPrng();
+        int chance = Misc::Rng::rollDice(100, prng) + 1; // 1..100
         int sum = 0;
         int i = 0;
         for(; static_cast<size_t>(i) < mChances.size(); ++i)
@@ -685,7 +687,8 @@ namespace MWWorld
             currentSpeed = targetSpeed;
 
         float multiplier = mWeatherSettings[weatherId].mRainEffect.empty() ? 1.f : 0.5f;
-        float updatedSpeed = (Misc::Rng::rollClosedProbability() - 0.5f) * multiplier * targetSpeed + currentSpeed;
+        auto& prng = MWBase::Environment::get().getWorld()->getPrng();
+        float updatedSpeed = (Misc::Rng::rollClosedProbability(prng) - 0.5f) * multiplier * targetSpeed + currentSpeed;
 
         if (updatedSpeed > 0.5f * targetSpeed && updatedSpeed < 2.f * targetSpeed)
             currentSpeed = updatedSpeed;