Take vanilla/TRNG stuff out of Tracks.lua (which is now no longer needed) and partially replicate it in the C++ side of things.

Common/Sound/sound.h

@@ -101,13 +101,14 @@ struct SampleInfo
 
 struct SoundTrackInfo
 {
-	std::string Name;
-	SOUNDTRACK_PLAYTYPE Mode;
-	int Mask;
+	std::string Name{};
+	SOUNDTRACK_PLAYTYPE Mode{ SOUNDTRACK_PLAYTYPE::OneShot };
+	int Mask{ 0 };
 };
 
 extern std::map<std::string, int> SoundTrackMap;
-extern std::vector<SoundTrackInfo> SoundTracks;
+extern std::unordered_map<int, SoundTrackInfo> SoundTracks;
+extern int SecretSoundIndex;
 
 long SoundEffect(int effectID, PHD_3DPOS* position, int env_flags, float pitchMultiplier = 1.0f, float gainMultiplier = 1.0f);
 void StopSoundEffect(short effectID);
@@ -124,6 +125,7 @@ void PlaySecretTrack();
 void SayNo();
 void PlaySoundSources();
 int  GetShatterSound(int shatterID);
+void EnumerateLegacyTracks();
 
 std::pair<std::string, QWORD> GetSoundTrackNameAndPosition(SOUNDTRACK_PLAYTYPE type);
 

Scripting/src/GameFlowScript.cpp

@@ -85,17 +85,6 @@ settings.lua shouldn't be bundled with any finished levels/games.
 */
 	m_lua->set_function("SetAnimations", &GameFlow::SetAnimations, this);
 
-/*** tracks.lua.
-__TODO CONFIRM PROPER BEHAVIOUR__
-@section trackslua
-*/
-/***
-@function SetAudioTracks
-@tparam table table array-style table with @{AudioTrack} objects 
-*/
-//TODO confirm proper behaviour
-	m_lua->set_function("SetAudioTracks", &GameFlow::SetAudioTracks, this);
-
 /*** strings.lua. 
 These functions used in strings.lua, which is generated by TombIDE.
 You will not need to call them manually.
@@ -181,24 +170,9 @@ void GameFlow::SetGameFarView(byte val)
 	}
 }
 
-void GameFlow::SetAudioTracks(sol::as_table_t<std::vector<GameScriptAudioTrack>>&& src)
-{
-	std::vector<GameScriptAudioTrack> tracks = std::move(src);
-	SoundTracks.clear();
-
-	for (auto t : tracks) {
-		SoundTrackInfo track;
-		track.Name = t.trackName;
-		track.Mask = 0;
-		track.Mode = t.looped ? SOUNDTRACK_PLAYTYPE::BGM : SOUNDTRACK_PLAYTYPE::OneShot;
-		SoundTracks.push_back(track);
-	}
-}
-
 void GameFlow::LoadGameFlowScript()
 {
 	ExecuteScript("Scripts/Enums.lua");
-	ExecuteScript("Scripts/Tracks.lua");
 	ExecuteScript("Scripts/Gameflow.lua");
 	ExecuteScript("Scripts/Strings.lua");
 	ExecuteScript("Scripts/Settings.lua");

Scripting/src/GameFlowScript.h

@@ -38,7 +38,6 @@ public:
 	~GameFlow();
 
 	void							AddLevel(GameScriptLevel const& level);
-	void							SetAudioTracks(sol::as_table_t<std::vector<GameScriptAudioTrack>>&& src);
 	void							LoadGameFlowScript();
 	char const *					GetString(const char* id) const;
 	void							SetStrings(sol::nested<std::unordered_map<std::string, std::vector<std::string>>> && src);

TR5Main/Game/savegame.cpp

@@ -474,7 +474,7 @@ bool SaveGame::Save(int slot)
 
 	// Legacy soundtrack map
 	std::vector<int> soundTrackMap;
-	for (auto& track : SoundTracks) { soundTrackMap.push_back(track.Mask); }
+	for (auto& track : SoundTracks) { soundTrackMap.push_back(track.second.Mask); }
 	auto soundtrackMapOffset = fbb.CreateVector(soundTrackMap);
 
 	// Flipmaps

TR5Main/Sound/sound.cpp

@@ -2,6 +2,7 @@
 #include "Sound/sound.h"
 
 #include <filesystem>
+#include <regex>
 #include "Game/camera.h"
 #include "Game/Lara/lara.h"
 #include "Game/room.h"
@@ -29,7 +30,8 @@ const BASS_BFX_FREEVERB BASS_ReverbTypes[(int)REVERB_TYPE::Count] =    // Reverb
 const std::string TRACKS_PATH = "Audio\\";
 
 std::map<std::string, int> SoundTrackMap;
-std::vector<SoundTrackInfo> SoundTracks;
+std::unordered_map<int, SoundTrackInfo> SoundTracks;
+int SecretSoundIndex;
 
 static int GlobalMusicVolume;
 static int GlobalFXVolume;
@@ -310,6 +312,35 @@ void FreeSamples()
 		Sound_FreeSample(i);
 }
 
+void EnumerateLegacyTracks()
+{
+	auto dir = std::filesystem::path(TRACKS_PATH);
+	// capture three-digit filenames, or those which start with three digits.
+	std::regex upToThreeDigits("\\\\((\\d{1,3})[^\\.]*)");
+	std::smatch result;
+	for (const auto& file : std::filesystem::directory_iterator{ dir })
+	{
+		std::string fileName = file.path().string();
+		auto bResult = std::regex_search(fileName, result, upToThreeDigits);
+		if (!result.empty())
+		{
+			// result[0] is the whole match including the leading backslash, so ignore it
+			// result[1] is the full file name, not including the extension
+			int index = std::stoi(result[2].str());
+			SoundTrackInfo s;
+			
+			// TRLE default looping tracks
+			if (index >= 98 && index <= 111)
+			{
+				s.Mode = SOUNDTRACK_PLAYTYPE::BGM;
+			}
+			s.Name = result[1];
+			SoundTracks.insert(std::make_pair(index, s));
+			SecretSoundIndex = std::max(SecretSoundIndex, index);
+		}
+	}
+}
+
 void PlaySoundTrack(std::string track, SOUNDTRACK_PLAYTYPE mode, QWORD position)
 {
 	if (track.empty())
@@ -456,7 +487,7 @@ void StopSoundTracks()
 
 void ClearSoundTrackMasks()
 {
-	for (auto& track : SoundTracks) { track.Mask = 0; }
+	for (auto& track : SoundTracks) { track.second.Mask = 0; }
 }
 
 // Returns specified soundtrack type's stem name and playhead position.
@@ -801,7 +832,7 @@ void SayNo()
 void PlaySecretTrack()
 {
 	// Secret soundtrack should be always last one on a list.	
-	PlaySoundTrack(SoundTracks.back().Name, SOUNDTRACK_PLAYTYPE::OneShot);
+	PlaySoundTrack(SoundTracks.at(SecretSoundIndex).Name, SOUNDTRACK_PLAYTYPE::OneShot);
 }
 
 int GetShatterSound(int shatterID)

TR5Main/Specific/winmain.cpp

@@ -157,6 +157,9 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 	
 	InitTENLog();
 
+	// Collect numbered tracks
+	EnumerateLegacyTracks();
+
 	// Initialise the new scripting system
 	ScriptInterfaceState::Init();