[Fix] IT: Tone Portamento + Volume Slide (Lxx) always executes the "p…

…ortamento down" branch when no tone portamento has been set up before. Test cases: LxxWith0Portamento-Linear.it, LxxWith0Portamento-Amiga.it [Mod] OpenMPT: Version is now 1.32.00.37 git-svn-id: https://source.openmpt.org/svn/openmpt/trunk/OpenMPT@22552 56274372-70c3-4bfc-bfc3-4c3a0b034d27
OpenMPT · Dec 14, 2024 · 303f5ee · 303f5ee
1 parent ad823b5
commit 303f5ee
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Showing 2 changed files with 10 additions and 2 deletions.
diff --git a/common/versionNumber.h b/common/versionNumber.h
@@ -16,4 +16,4 @@
 #define VER_MAJORMAJOR  1
 #define VER_MAJOR      32
 #define VER_MINOR      00
-#define VER_MINORMINOR 36
+#define VER_MINORMINOR 37
diff --git a/soundlib/Snd_fx.cpp b/soundlib/Snd_fx.cpp
@@ -4587,7 +4587,15 @@ int32 CSoundFile::TonePortamento(PlayState &playState, CHANNELINDEX nChn, uint16
 	if(chn.nPeriod && chn.nPortamentoDest && doPorta)
 	{
 		const int32 actualDelta = PeriodsAreFrequencies() ? delta : -delta;
-		if(chn.nPeriod < chn.nPortamentoDest || chn.portaTargetReached)
+		// IT compatibility: Command Lxx, with no tone portamento set up before, will always execute the "portamento down" branch.
+		// Test cases: LxxWith0Portamento-Linear.it, LxxWith0Portamento-Amiga.it
+		if(m_playBehaviour[kITDoublePortamentoSlides] && !delta && chn.rowCommand.command == CMD_TONEPORTAVOL)
+		{
+			if(chn.nPeriod > 1 && m_SongFlags[SONG_LINEARSLIDES])
+				chn.nPeriod--;
+			if(chn.nPeriod < chn.nPortamentoDest)
+				chn.nPeriod = chn.nPortamentoDest;
+		} else if(chn.nPeriod < chn.nPortamentoDest || chn.portaTargetReached)
 		{
 			DoFreqSlide(chn, chn.nPeriod, actualDelta, true);
 			if(chn.nPeriod > chn.nPortamentoDest)