From d1fa1e6acf5107bc6d520d486eb0f35359ab0676 Mon Sep 17 00:00:00 2001
From: Spacek531 <spacek531@comcast.net>
Date: Mon, 4 Nov 2024 22:07:21 -0800
Subject: [PATCH] remove GetRelativeSpeed

---
 src/openrct2/ride/RideData.cpp    |  5 -----
 src/openrct2/ride/Track.h         |  3 ++-
 src/openrct2/ride/TrackDesign.cpp |  7 ++++---
 src/openrct2/ride/Vehicle.cpp     | 11 ++++-------
 4 files changed, 10 insertions(+), 16 deletions(-)

diff --git a/src/openrct2/ride/RideData.cpp b/src/openrct2/ride/RideData.cpp
index 649c39590699..47ebc00e09ea 100644
--- a/src/openrct2/ride/RideData.cpp
+++ b/src/openrct2/ride/RideData.cpp
@@ -452,11 +452,6 @@ TrackDrawerEntry getTrackDrawerEntry(const RideTypeDescriptor& rtd, bool isInver
     return descriptor.Regular;
 }
 
-int32_t RideTypeDescriptor::GetRelativeBoosterSpeed(const int32_t& absoluteSpeed) const
-{
-    return absoluteSpeed * 2 / LegacyBoosterSettings.BoosterSpeedFactor;
-}
-
 int32_t RideTypeDescriptor::GetAbsoluteBoosterSpeed(const int32_t& relativeSpeed) const
 {
     // BoosterSpeedFactor has valid values of 1, 2, 4 representing a 1/2, 1, and 2 multiplier of relative speed to absolute
diff --git a/src/openrct2/ride/Track.h b/src/openrct2/ride/Track.h
index fa07b790e186..a1a685e044bb 100644
--- a/src/openrct2/ride/Track.h
+++ b/src/openrct2/ride/Track.h
@@ -20,7 +20,8 @@ constexpr uint8_t kRCT2DefaultBlockBrakeSpeed = 2;
 constexpr int32_t kBlockBrakeBaseSpeed = 0x20364;
 constexpr int32_t kBlockBrakeSpeedOffset = kBlockBrakeBaseSpeed - (kRCT2DefaultBlockBrakeSpeed << 16);
 constexpr uint8_t kLegacyBrakeSpeedMultiplier = 2;
-constexpr uint8_t kLegacyBrakeSpeedMask = 0b00011110;
+constexpr uint8_t kLegacyBrakeSpeedMask = 0b00001111;
+constexpr uint8_t kLegacyBrakeSpeedMax = 0b00011110;
 constexpr uint8_t kMaximumTrackSpeed = 0b00111111; // 2 high bits reserved for potential future behavior
 
 namespace OpenRCT2
diff --git a/src/openrct2/ride/TrackDesign.cpp b/src/openrct2/ride/TrackDesign.cpp
index 92d083626891..2a0afa90ff37 100644
--- a/src/openrct2/ride/TrackDesign.cpp
+++ b/src/openrct2/ride/TrackDesign.cpp
@@ -239,11 +239,12 @@ ResultWithMessage TrackDesign::CreateTrackDesignTrack(TrackDesignState& tds, con
             trackFlags = trackElement.element->AsTrack()->GetBrakeBoosterSpeed();
             if (track.type == TrackElemType::Booster)
             {
-                trackFlags = ride.GetRideTypeDescriptor().GetRelativeBoosterSpeed(trackFlags);
+                // convert absolute speed into legacy speed units
+                trackFlags *= 2 / ride.GetRideTypeDescriptor().LegacyBoosterSettings.BoosterSpeedFactor;
             }
 
             // check to ensure the value is serialisable. This warning will not apply to new track design format.
-            bool tooHigh = trackFlags > kLegacyBrakeSpeedMask;
+            bool tooHigh = trackFlags > kLegacyBrakeSpeedMax;
             bool tooPrecise = trackFlags & 1;
             if (tooPrecise || tooHigh)
             {
@@ -253,7 +254,7 @@ ResultWithMessage TrackDesign::CreateTrackDesignTrack(TrackDesignState& tds, con
             {
                 trackFlags += 1;
             }
-            trackFlags = std::min<uint8_t>(trackFlags, kLegacyBrakeSpeedMask);
+            trackFlags = std::min<uint8_t>(trackFlags, kLegacyBrakeSpeedMax);
 
             trackFlags /= kLegacyBrakeSpeedMultiplier;
             trackFlags &= 0xF;
diff --git a/src/openrct2/ride/Vehicle.cpp b/src/openrct2/ride/Vehicle.cpp
index 05ef11cdbe8b..771158dd448a 100644
--- a/src/openrct2/ride/Vehicle.cpp
+++ b/src/openrct2/ride/Vehicle.cpp
@@ -6836,13 +6836,10 @@ void Vehicle::Sub6DBF3E()
 
 static uint8_t GetLegacyBoosterSpeed(uint8_t rawSpeed, RideTypeDescriptor& vehicleRTD, RideTypeDescriptor& trackRTD)
 {
-    auto relativeSpeed = trackRTD.GetRelativeBoosterSpeed(rawSpeed);
-    relativeSpeed &= kLegacyBrakeSpeedMask;
-    auto finalSpeed = vehicleRTD.GetAbsoluteBoosterSpeed(relativeSpeed);
-    auto finalSpeed2 = (rawSpeed * vehicleRTD.LegacyBoosterSettings.BoosterSpeedFactor
-                        / trackRTD.LegacyBoosterSettings.BoosterSpeedFactor)
-        & (15 * vehicleRTD.LegacyBoosterSettings.BoosterSpeedFactor);
-    assert(finalSpeed == finalSpeed2);
+    // convert between speed regimes and mask to the highest 4 bits
+    auto finalSpeed = (rawSpeed * vehicleRTD.LegacyBoosterSettings.BoosterSpeedFactor
+                       / trackRTD.LegacyBoosterSettings.BoosterSpeedFactor)
+        & (kLegacyBrakeSpeedMask * vehicleRTD.LegacyBoosterSettings.BoosterSpeedFactor);
     return finalSpeed;
 }