Implement palette fading

svn-id: r45455

1 files changed, 24 insertions, 1 deletions

diff --git a/engines/draci/game.cpp b/engines/draci/game.cpp
index b162e0195e..b2e28b70a7 100644
--- a/engines/draci/game.cpp
+++ b/engines/draci/game.cpp
@@ -165,6 +165,7 @@ void Game::init() {
 	setQuit(false);
 	setExitLoop(false);
 	_scheduledPalette = 0;
+	_fadePhases = _fadePhase = 0;
 	setLoopStatus(kStatusGate);
 	setLoopSubstatus(kSubstatusOrdinary);
 
@@ -239,6 +240,22 @@ void Game::loop() {
 		if (shouldExitLoop() > 1)	// after loading
 			break;
 
+		if (_fadePhase > 0 && (_vm->_system->getMillis() - _fadeTick) >= kFadingTimeUnit) {
+			_fadeTick = _vm->_system->getMillis();
+			--_fadePhase;
+			const BAFile *startPal = _vm->_paletteArchive->getFile(_currentRoom._palette);
+			const BAFile *endPal = getScheduledPalette() >= 0 ? _vm->_paletteArchive->getFile(getScheduledPalette()) : NULL;
+			_vm->_screen->interpolatePalettes(startPal->_data, endPal->_data, 0, kNumColours, _fadePhases - _fadePhase, _fadePhases);
+			if (_loopSubstatus == kSubstatusFade && _fadePhase == 0) {
+				setExitLoop(true);
+				// Rewrite the palette index of the current
+				// room.  This is necessary when two fadings
+				// are called after each other, such as in the
+				// intro.  We rely on that getScheduledPalette() >= 0.
+				_currentRoom._palette = getScheduledPalette();
+			}
+		}
+
 		// Fetch mouse coordinates
 		int x = _vm->_mouse->getPosX();
 		int y = _vm->_mouse->getPosY();
@@ -1530,8 +1547,9 @@ void Game::setSpeechTiming(uint tick, uint duration) {
 	_speechDuration = duration;
 }
 
-void Game::shiftSpeechTick(int delta) {
+void Game::shiftSpeechAndFadeTick(int delta) {
 	_speechTick += delta;
+	_fadeTick += delta;
 }
 
 int Game::getEscRoom() const {
@@ -1550,6 +1568,11 @@ int Game::getScheduledPalette() const {
 	return _scheduledPalette;
 }
 
+void Game::initializeFading(int phases) {
+	_fadePhases = _fadePhase = phases;
+	_fadeTick = _vm->_system->getMillis();
+}
+
 /**
  * The GPL command Mark sets the animation index (which specifies the order in which
  * animations were loaded in) which is then used by the Release command to delete