ZVISION: Implement crossfade.

5 files changed, 50 insertions, 8 deletions

diff --git a/engines/zvision/actions.cpp b/engines/zvision/actions.cpp
index 92d6f6c389..5d1dc9a608 100644
--- a/engines/zvision/actions.cpp
+++ b/engines/zvision/actions.cpp
@@ -121,12 +121,32 @@ bool ActionChangeLocation::execute() {
 ActionCrossfade::ActionCrossfade(ZVision *engine, int32 slotkey, const Common::String &line) :
 	ResultAction(engine, slotkey) {
 	sscanf(line.c_str(),
-	       "%u %u %u %u %u %u %u",
+	       "%u %u %d %d %d %d %d",
 	       &_keyOne, &_keyTwo, &_oneStartVolume, &_twoStartVolume, &_oneEndVolume, &_twoEndVolume, &_timeInMillis);
 }
 
 bool ActionCrossfade::execute() {
-	// TODO: Implement
+	if (_keyOne) {
+		SideFX *fx = _engine->getScriptManager()->getSideFX(_keyOne);
+		if (fx && fx->getType() == SideFX::SIDEFX_AUDIO) {
+			MusicNode *mus = (MusicNode *)fx;
+			if (_oneStartVolume >= 0)
+				mus->setVolume((_oneStartVolume * 255) / 100);
+
+			mus->setFade(_timeInMillis, (_oneEndVolume * 255) / 100);
+		}
+	}
+
+	if (_keyTwo) {
+		SideFX *fx = _engine->getScriptManager()->getSideFX(_keyTwo);
+		if (fx && fx->getType() == SideFX::SIDEFX_AUDIO) {
+			MusicNode *mus = (MusicNode *)fx;
+			if (_twoStartVolume >= 0)
+				mus->setVolume((_twoStartVolume * 255) / 100);
+
+			mus->setFade(_timeInMillis, (_twoEndVolume * 255) / 100);
+		}
+	}
 	return true;
 }
 
diff --git a/engines/zvision/actions.h b/engines/zvision/actions.h
index b204fbeb28..5c6cf6c35f 100644
--- a/engines/zvision/actions.h
+++ b/engines/zvision/actions.h
@@ -140,11 +140,11 @@ public:
 private:
 	uint32 _keyOne;
 	uint32 _keyTwo;
-	uint _oneStartVolume;
-	uint _twoStartVolume;
-	uint _oneEndVolume;
-	uint _twoEndVolume;
-	uint _timeInMillis;
+	int32 _oneStartVolume;
+	int32 _twoStartVolume;
+	int32 _oneEndVolume;
+	int32 _twoEndVolume;
+	int32 _timeInMillis;
 };
 
 class ActionDebug : public ResultAction {
diff --git a/engines/zvision/music_node.cpp b/engines/zvision/music_node.cpp
index 081c9dbcca..30271480c1 100644
--- a/engines/zvision/music_node.cpp
+++ b/engines/zvision/music_node.cpp
@@ -91,12 +91,31 @@ void MusicNode::unsetPanTrack() {
 	setVolume(_volume);
 }
 
+void MusicNode::setFade(int32 time, uint8 target) {
+	_crossfade_target = target;
+	_crossfade_time = time;
+	_crossfade = true;
+}
+
 bool MusicNode::process(uint32 deltaTimeInMillis) {
 	if (! _engine->_mixer->isSoundHandleActive(_handle))
 		return stop();
 	else {
 		uint8 _newvol = _volume;
 
+		if (_crossfade) {
+			if (_crossfade_time > 0) {
+				if ((int32)deltaTimeInMillis > _crossfade_time)
+					deltaTimeInMillis = _crossfade_time;
+				_newvol += floor(((float)(_crossfade_target - _newvol) / (float)_crossfade_time)) * (float)deltaTimeInMillis;
+				_crossfade_time -= deltaTimeInMillis;
+			}
+			else {
+				_crossfade = false;
+				_newvol = _crossfade_target;
+			}
+		}
+
 		if (_pantrack || _volume != _newvol)
 			setVolume(_newvol);
 	}
diff --git a/engines/zvision/music_node.h b/engines/zvision/music_node.h
index 9ccf9ab657..6e3033f6b0 100644
--- a/engines/zvision/music_node.h
+++ b/engines/zvision/music_node.h
@@ -49,6 +49,9 @@ public:
 
 	void setPanTrack(int16 pos);
 	void unsetPanTrack();
+
+	void setFade(int32 time, uint8 target);
+
 private:
 	int32 _timeLeft;
 	bool _pantrack;
diff --git a/engines/zvision/scr_file_handling.cpp b/engines/zvision/scr_file_handling.cpp
index 002871af0b..833db11ad1 100644
--- a/engines/zvision/scr_file_handling.cpp
+++ b/engines/zvision/scr_file_handling.cpp
@@ -220,7 +220,7 @@ void ScriptManager::parseResults(Common::SeekableReadStream &stream, Common::Lis
 				} else if (act.matchString("change_location", true)) {
 					actionList.push_back(new ActionChangeLocation(_engine, slot, args));
 				} else if (act.matchString("crossfade", true)) {
-					// TODO: Implement ActionCrossfade
+					actionList.push_back(new ActionCrossfade(_engine, slot, args));
 				} else if (act.matchString("debug", true)) {
 					// TODO: Implement ActionDebug
 				} else if (act.matchString("delay_render", true)) {