From d8d706cc58b2fae849a35d844500e0c5e75af869 Mon Sep 17 00:00:00 2001
From: duncanspumpkin <duncans_pumpkin@hotmail.co.uk>
Date: Tue, 12 Jan 2016 17:55:19 +0000
Subject: [PATCH] Fix #2700. Friction sound no longer goes very quite at high
 speeds.

Also labelled friction_sound_id and small refactor
---
 src/ride/ride_data.c |  2 +-
 src/ride/vehicle.c   | 10 +++++-----
 src/ride/vehicle.h   |  2 +-
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/ride/ride_data.c b/src/ride/ride_data.c
index 2a20c03721..83317353e1 100644
--- a/src/ride/ride_data.c
+++ b/src/ride/ride_data.c
@@ -1290,7 +1290,7 @@ const rct_ride_type_vehicle CableLiftVehicle = {
 	.no_seating_rows = 0,
 	.spinning_inertia = 0,
 	.spinning_friction = 255,
-	.var_57 = 0,
+	.friction_sound_id = 0,
 	.var_58 = 0,
 	.sound_range = 0,
 	.var_5A = 0,
diff --git a/src/ride/vehicle.c b/src/ride/vehicle.c
index f70dcd2e16..1c1360569b 100644
--- a/src/ride/vehicle.c
+++ b/src/ride/vehicle.c
@@ -4256,8 +4256,8 @@ static void vehicle_update_sound(rct_vehicle *vehicle)
 {
 	rct_ride *ride;
 	rct_ride_type *rideEntry;
-	// bl should be set before hand
-	uint8 bl = 255, dl = 255;
+	// frictionVolume (bl) should be set before hand
+	uint8 frictionVolume = 255, frictionId = 255;
 	// bh screamVolume should be set before hand
 	uint8 screamId, screamVolume = 255;
 	uint16 soundIdVolume;
@@ -4269,9 +4269,9 @@ static void vehicle_update_sound(rct_vehicle *vehicle)
 
 	int ecx = abs(vehicle->velocity) - 0x10000;
 	if (ecx >= 0) {
-		dl = vehicleEntry->var_57;
+		frictionId = vehicleEntry->friction_sound_id;
 		ecx >>= 15;
-		bl = min(208 + ecx & 0xFF, 255);
+		frictionVolume = min(208 + (ecx & 0xFF), 255);
 	}
 
 	switch (vehicleEntry->sound_range) {
@@ -4328,7 +4328,7 @@ static void vehicle_update_sound(rct_vehicle *vehicle)
 	}
 
 	// Friction sound
-	soundIdVolume = sub_6D7AC0(vehicle->sound1_id, vehicle->sound1_volume, dl, bl);
+	soundIdVolume = sub_6D7AC0(vehicle->sound1_id, vehicle->sound1_volume, frictionId, frictionVolume);
 	vehicle->sound1_id = soundIdVolume & 0xFF;
 	vehicle->sound1_volume = (soundIdVolume >> 8) & 0xFF;
 
diff --git a/src/ride/vehicle.h b/src/ride/vehicle.h
index 367cfc1644..59f7ca3353 100644
--- a/src/ride/vehicle.h
+++ b/src/ride/vehicle.h
@@ -67,7 +67,7 @@ typedef struct {
 	uint8 no_seating_rows;			// 0x54 , 0x6E
 	uint8 spinning_inertia;			// 0x55 , 0x6F
 	uint8 spinning_friction;		// 0x56 , 0x70
-	uint8 var_57;					// 0x57 , 0x71
+	uint8 friction_sound_id;		// 0x57 , 0x71
 	uint8 var_58;					// 0x58 , 0x72
 	uint8 sound_range;				// 0x59 , 0x73
 	uint8 var_5A;					// 0x5A , 0x74