Change #6684: Cutting point overrides for music base sets

This improves bad looping of title screen song from Windows TTD, and fixes
a long silence at the end of "Can't get there from here" from Windows TTD.

bin/baseset/orig_win.obm

@@ -142,5 +142,17 @@ GM_TT19.GM = Funk Central
 GM_TT20.GM = Jammit
 GM_TT21.GM = Movin' On
 
+; MIDI timecodes where the playback should attemp to start and stop short.
+; This is to allow fixing undesired silences in original MIDI files.
+; However not all music drivers may support this.
+[timingtrim]
+; Theme has two beats silence at the beginning which prevents clean looping.
+GM_TT00.GM = 768:53760
+; Can't Get There From Here from the Windows version has a long silence at the end,
+; followed by a solo repeat. This isn't in the original DOS version music and is likely
+; unintentional from the people who converted the music from the DOS version.
+; Actual song ends after measure 152.
+GM_TT10.GM = 0:235008
+
 [origin]
 default      = You can find it on your Transport Tycoon Deluxe CD-ROM.

media/baseset/orig_win.obm

@@ -90,5 +90,17 @@ GM_TT19.GM = Funk Central
 GM_TT20.GM = Jammit
 GM_TT21.GM = Movin' On
 
+; MIDI timecodes where the playback should attemp to start and stop short.
+; This is to allow fixing undesired silences in original MIDI files.
+; However not all music drivers may support this.
+[timingtrim]
+; Theme has two beats silence at the beginning which prevents clean looping.
+GM_TT00.GM = 768:53760
+; Can't Get There From Here from the Windows version has a long silence at the end,
+; followed by a solo repeat. This isn't in the original DOS version music and is likely
+; unintentional from the people who converted the music from the DOS version.
+; Actual song ends after measure 152.
+GM_TT10.GM = 0:235008
+
 [origin]
 default      = You can find it on your Transport Tycoon Deluxe CD-ROM.

src/base_media_base.h

@@ -301,6 +301,8 @@ struct MusicSongInfo {
 	const char *filename;    ///< file on disk containing song (when used in MusicSet class, this pointer is owned by MD5File object for the file)
 	MusicTrackType filetype; ///< decoder required for song file
 	int cat_index;           ///< entry index in CAT file, for filetype==MTT_MPSMIDI
+	int override_start;      ///< MIDI ticks to skip over in beginning
+	int override_end;        ///< MIDI tick to end the song at (0 if no override)
 };
 
 /** All data of a music set. */

src/music.cpp

@@ -125,6 +125,7 @@ bool MusicSet::FillSetDetails(IniFile *ini, const char *path, const char *full_f
 		this->num_available = 0;
 		IniGroup *names = ini->GetGroup("names");
 		IniGroup *catindex = ini->GetGroup("catindex");
+		IniGroup *timingtrim = ini->GetGroup("timingtrim");
 		for (uint i = 0, j = 1; i < lengthof(this->songinfo); i++) {
 			const char *filename = this->files[i].filename;
 			if (names == NULL || StrEmpty(filename)) {
@@ -150,15 +151,16 @@ bool MusicSet::FillSetDetails(IniFile *ini, const char *path, const char *full_f
 				this->songinfo[i].filetype = MTT_STANDARDMIDI;
 			}
 
+			const char *trimmed_filename = filename;
 			/* As we possibly add a path to the filename and we compare
 			 * on the filename with the path as in the .obm, we need to
 			 * keep stripping path elements until we find a match. */
-			for (const char *p = filename; p != NULL; p = strchr(p, PATHSEPCHAR)) {
+			for (; trimmed_filename != NULL; trimmed_filename = strchr(trimmed_filename, PATHSEPCHAR)) {
 				/* Remove possible double path separator characters from
 				 * the beginning, so we don't start reading e.g. root. */
-				while (*p == PATHSEPCHAR) p++;
+				while (*trimmed_filename == PATHSEPCHAR) trimmed_filename++;
 
-				item = names->GetItem(p, false);
+				item = names->GetItem(trimmed_filename, false);
 				if (item != NULL && !StrEmpty(item->value)) break;
 			}
 
@@ -173,6 +175,15 @@ bool MusicSet::FillSetDetails(IniFile *ini, const char *path, const char *full_f
 			this->num_available++;
 
 			this->songinfo[i].tracknr = j++;
+
+			item = timingtrim->GetItem(trimmed_filename, false);
+			if (item != NULL && !StrEmpty(item->value)) {
+				const char *endpos = strchr(item->value, ':');
+				if (endpos != NULL) {
+					this->songinfo[i].override_start = atoi(item->value);
+					this->songinfo[i].override_end = atoi(endpos + 1);
+				}
+			}
 		}
 	}
 	return ret;

src/music/dmusic.cpp

@@ -723,14 +723,6 @@ static void MidiThreadProc(void *)
 			while (current_block < current_file.blocks.size()) {
 				MidiFile::DataBlock &block = current_file.blocks[current_block];
 
-				/* check that block is not in the future */
-				REFERENCE_TIME playback_time = current_time - playback_start_time;
-				if (block.realtime * MIDITIME_TO_REFTIME > playback_time +  3 *_playback.preload_time * MS_TO_REFTIME) {
-					/* Stop the thread loop until we are at the preload time of the next block. */
-					next_timeout = Clamp(((int64)block.realtime * MIDITIME_TO_REFTIME - playback_time) / MS_TO_REFTIME - _playback.preload_time, 0, 1000);
-					DEBUG(driver, 9, "DMusic thread: Next event in %u ms (music %u, ref %lld)", next_timeout, block.realtime * MIDITIME_TO_REFTIME, playback_time);
-					break;
-				}
 				/* check that block isn't at end-of-song override */
 				if (current_segment.end > 0 && block.ticktime >= current_segment.end) {
 					if (current_segment.loop) {
@@ -743,6 +735,14 @@ static void MidiThreadProc(void *)
 					next_timeout = 0;
 					break;
 				}
+				/* check that block is not in the future */
+				REFERENCE_TIME playback_time = current_time - playback_start_time;
+				if (block.realtime * MIDITIME_TO_REFTIME > playback_time +  3 *_playback.preload_time * MS_TO_REFTIME) {
+					/* Stop the thread loop until we are at the preload time of the next block. */
+					next_timeout = Clamp(((int64)block.realtime * MIDITIME_TO_REFTIME - playback_time) / MS_TO_REFTIME - _playback.preload_time, 0, 1000);
+					DEBUG(driver, 9, "DMusic thread: Next event in %u ms (music %u, ref %lld)", next_timeout, block.realtime * MIDITIME_TO_REFTIME, playback_time);
+					break;
+				}
 
 				/* Timestamp of the current block. */
 				block_time = playback_start_time + block.realtime * MIDITIME_TO_REFTIME;
@@ -1232,8 +1232,8 @@ void MusicDriver_DMusic::PlaySong(const MusicSongInfo &song)
 
 	if (!_playback.next_file.LoadSong(song)) return;
 
-	_playback.next_segment.start = 0;
-	_playback.next_segment.end = 0;
+	_playback.next_segment.start = song.override_start;
+	_playback.next_segment.end = song.override_end;
 	_playback.next_segment.loop = false;
 
 	_playback.do_start = true;

src/music/win32_m.cpp

@@ -209,10 +209,6 @@ void CALLBACK TimerCallback(UINT uTimerID, UINT, DWORD_PTR dwUser, DWORD_PTR, DW
 	while (_midi.current_block < _midi.current_file.blocks.size()) {
 		MidiFile::DataBlock &block = _midi.current_file.blocks[_midi.current_block];
 
-		/* check that block is not in the future */
-		if (block.realtime / 1000 > playback_time) {
-			break;
-		}
 		/* check that block isn't at end-of-song override */
 		if (_midi.current_segment.end > 0 && block.ticktime >= _midi.current_segment.end) {
 			if (_midi.current_segment.loop) {
@@ -223,6 +219,10 @@ void CALLBACK TimerCallback(UINT uTimerID, UINT, DWORD_PTR dwUser, DWORD_PTR, DW
 			}
 			break;
 		}
+		/* check that block is not in the future */
+		if (block.realtime / 1000 > playback_time) {
+			break;
+		}
 
 		byte *data = block.data.Begin();
 		size_t remaining = block.data.Length();
@@ -315,8 +315,8 @@ void MusicDriver_Win32::PlaySong(const MusicSongInfo &song)
 		return;
 	}
 
-	_midi.next_segment.start = 0;
-	_midi.next_segment.end = 0;
+	_midi.next_segment.start = song.override_start;
+	_midi.next_segment.end = song.override_end;
 	_midi.next_segment.loop = false;
 
 	DEBUG(driver, 2, "Win32-MIDI: PlaySong: setting flag");