Committed by patch #2219361 ("BS1: Simplified subtitles"). It uses the

lockScreen() / unlockScreen() backend API, instead of copyRectToScreen().
Before, it had to copy a piece of the engine's screen to draw on to simulate
transparency, which was awkward.

However, this means we're now forcing full-screen updates on each frame. There
may be performance regressions, particularly if the frames are much smaller
than the screen. Hopefully, it's the decoding that's the bottleneck, but if
this causes problems on low-end devices... well, Fingolfin had some ideas about
that when he first proposed the lockScreen() / unlockScreen() API.

svn-id: r35115

2 files changed, 19 insertions, 36 deletions

diff --git a/engines/sword1/animation.cpp b/engines/sword1/animation.cpp
index c0cd85a7c2..592cc2e565 100644
--- a/engines/sword1/animation.cpp
+++ b/engines/sword1/animation.cpp
@@ -36,6 +36,7 @@
 #include "common/str.h"
 #include "common/events.h"
 #include "common/system.h"
+#include "graphics/surface.h"
 
 namespace Sword1 {
 
@@ -70,7 +71,6 @@ MoviePlayer::MoviePlayer(SwordEngine *vm, Screen *screen, Text *textMan, Audio::
 	: _vm(vm), _screen(screen), _textMan(textMan), _snd(snd), _system(system) {
 	_bgSoundStream = NULL;
 	_ticks = 0;
-	_textSpriteBuf = NULL;
 	_black = 1;
 	_white = 255;
 	_currentFrame = 0;
@@ -275,12 +275,9 @@ void MoviePlayer::play(void) {
 				_textHeight = frame->height;
 				_textX = 320 - _textWidth / 2;
 				_textY = 420 - _textHeight;
-				_textSpriteBuf = (byte *)calloc(_textHeight, _textWidth);
 			}
 			if (_currentFrame == _movieTexts[0]->_endFrame) {
 				_textMan->releaseText(2, false);
-				free(_textSpriteBuf);
-				_textSpriteBuf = NULL;
 				delete _movieTexts.remove_at(0);
 			}
 		}
@@ -309,11 +306,7 @@ void MoviePlayer::play(void) {
 	if (terminated)
 		_snd->stopHandle(_bgSoundHandle);
 
-	if (_textSpriteBuf) {
-		_textMan->releaseText(2, false);
-		free(_textSpriteBuf);
-		_textSpriteBuf = NULL;
-	}
+	_textMan->releaseText(2, false);
 
 	while (!_movieTexts.empty())
 		delete _movieTexts.remove_at(_movieTexts.size() - 1);
@@ -444,31 +437,26 @@ bool MoviePlayerDXA::decodeFrame(void) {
 }
 
 void MoviePlayerDXA::processFrame(void) {
-	// TODO: Handle the advanced cutscene packs. Do they really exist?
-
-	// We cannot draw the text to _drawBuffer, since that's one of the
-	// decoder's internal buffers. Instead, we copy part of _drawBuffer
-	// to the text sprite.
+}
 
-	if (_textSpriteBuf) {
-		memset(_textSpriteBuf, 0, _textWidth * _textHeight);
+void MoviePlayerDXA::updateScreen(void) {
+	_system->copyRectToScreen(_drawBuffer, _frameWidth, _frameX, _frameY, _frameWidth, _frameHeight);
 
-		// FIXME: This is inefficient
-		int x, y;
+	// TODO: Handle the advanced cutscene packs. Do they really exist?
 
-		for (y = _textY; y < _textY + _textHeight; y++) {
-			for (x = _textX; x < _textX + _textWidth; x++) {
-				if (x >= _frameX && x <= _frameX + _frameWidth && y >= _frameY && y <= _frameY + _frameHeight) {
-					_textSpriteBuf[(y - _textY) * _textWidth + x - _textX] = _drawBuffer[(y - _frameY) * _frameWidth + x - _frameX];
-				}
-			}
-		}
+	// We cannot draw the text to _drawBuffer, since that's one of the
+	// decoder's internal buffers, and besides it may be much smaller than
+	// the screen, so it's possible that the subtitles don't fit on it.
+	// Instead, we get the frame buffer from the backend, after copying the
+	// frame to it, and draw on that.
 
+	if (_textMan->giveSpriteData(2)) {
+		Graphics::Surface *frameBuffer = _system->lockScreen();
 		byte *src = (byte *)_textMan->giveSpriteData(2) + sizeof(FrameHeader);
-		byte *dst = _textSpriteBuf;
+		byte *dst = (byte *)frameBuffer->getBasePtr(_textX, _textY);
 
-		for (y = 0; y < _textHeight; y++) {
-			for (x = 0; x < _textWidth; x++) {
+		for (int y = 0; y < _textHeight; y++) {
+			for (int x = 0; x < _textWidth; x++) {
 				switch (src[x]) {
 				case BORDER_COL:
 					dst[x] = _black;
@@ -479,16 +467,12 @@ void MoviePlayerDXA::processFrame(void) {
 				}
 			}
 			src += _textWidth;
-			dst += _textWidth;
+			dst += frameBuffer->pitch;
 		}
-	}
-}
 
-void MoviePlayerDXA::updateScreen(void) {
-	_system->copyRectToScreen(_drawBuffer, _frameWidth, _frameX, _frameY, _frameWidth, _frameHeight);
-	if (_textSpriteBuf) {
-		_system->copyRectToScreen(_textSpriteBuf, _textWidth, _textX, _textY, _textWidth, _textHeight);
+		_system->unlockScreen();
 	}
+
 	_system->updateScreen();
 }
 
diff --git a/engines/sword1/animation.h b/engines/sword1/animation.h
index fd9c774190..6b74eb5833 100644
--- a/engines/sword1/animation.h
+++ b/engines/sword1/animation.h
@@ -92,7 +92,6 @@ protected:
 	Audio::Mixer *_snd;
 	OSystem *_system;
 	Common::Array<MovieText *> _movieTexts;
-	byte *_textSpriteBuf;
 	int _textX, _textY, _textWidth, _textHeight;
 	byte _black, _white;