Added channel remapping to MidiParser_SCI (currently unused)

svn-id: r49414

2 files changed, 25 insertions, 2 deletions

diff --git a/engines/sci/sound/midiparser_sci.cpp b/engines/sci/sound/midiparser_sci.cpp
index 2068ea9a33..83a67509cf 100644
--- a/engines/sci/sound/midiparser_sci.cpp
+++ b/engines/sci/sound/midiparser_sci.cpp
@@ -60,6 +60,9 @@ MidiParser_SCI::MidiParser_SCI(SciVersion soundVersion) :
 	_dataincToAdd = 0;
 	_resetOnPause = false;
 	_channelsUsed = 0;
+
+	for (int i = 0; i < 16; i++)
+		_channelRemap[i] = i;
 }
 
 MidiParser_SCI::~MidiParser_SCI() {
@@ -120,17 +123,26 @@ void MidiParser_SCI::unloadMusic() {
 	// Center the pitch wheels and hold pedal in preparation for the next piece of music
 	if (_driver) {
 		for (int i = 0; i < 16; ++i) {
-			if (_channelsUsed & (1 << i)) {
+			if (isChannelUsed(i)) {
 				_driver->send(0xE0 | i, 0, 0x40);	// Reset pitch wheel
 				_driver->send(0xB0 | i, 0x40, 0);	// Reset hold pedal
 			}
 		}
 	}
+
+	for (int i = 0; i < 16; i++)
+		_channelRemap[i] = i;
 }
 
 void MidiParser_SCI::parseNextEvent(EventInfo &info) {
+	byte remappedChannel = _channelRemap[info.channel()];
+
+	// Remap channel. Keep the upper 4 bits (command code) and change
+	// the lower 4 bits (channel)
+	info.event = (info.event & 0xF0) | (remappedChannel & 0xF);
+
 	// Monitor which channels are used by this song
-	_channelsUsed |= (1 << info.channel());
+	setChannelUsed(info.channel());
 
 	// Set signal AFTER waiting for delta, otherwise we would set signal too soon resulting in all sorts of bugs
 	if (_dataincAdd) {
diff --git a/engines/sci/sound/midiparser_sci.h b/engines/sci/sound/midiparser_sci.h
index f95c71ce2f..d9ae583aff 100644
--- a/engines/sci/sound/midiparser_sci.h
+++ b/engines/sci/sound/midiparser_sci.h
@@ -71,7 +71,16 @@ public:
 			jumpToTick(0);
 	}
 
+	void remapChannel(byte channel, byte newChannel) {
+		assert(channel < 0xF);		// don't touch special SCI channel 15
+		assert(newChannel < 0xF);	// don't touch special SCI channel 15
+		_channelRemap[channel] = newChannel;
+	}
+
 protected:
+	bool isChannelUsed(byte channel) { return _channelsUsed & (1 << channel); }
+	void setChannelUsed(byte channel) { _channelsUsed |= (1 << channel); }
+
 	void parseNextEvent(EventInfo &info);
 	byte *midiMixChannels();
 	byte *midiFilterChannels(int channelMask);
@@ -93,6 +102,8 @@ protected:
 	// A 16-bit mask, containing the channels used
 	// by the currently parsed song
 	uint16 _channelsUsed;
+
+	byte _channelRemap[16];
 };
 
 } // End of namespace Sci