SCI: Some work on robot videos

- The size of the videos is now calculated when they are loaded (this helps remove some
nasty hacks and constant memory reallocations and simplifies the code)
- Some work on frame placement (e.g. in robot 1305, Phantasmagoria)

svn-id: r55830

2 files changed, 61 insertions, 11 deletions

diff --git a/engines/sci/video/robot_decoder.cpp b/engines/sci/video/robot_decoder.cpp
index d243816ff7..8dd60cd9a6 100644
--- a/engines/sci/video/robot_decoder.cpp
+++ b/engines/sci/video/robot_decoder.cpp
@@ -76,6 +76,8 @@ enum robotPalTypes {
 
 RobotDecoder::RobotDecoder(Audio::Mixer *mixer, bool isBigEndian) {
 	_surface = 0;
+	_width = 0;
+	_height = 0;
 	_fileStream = 0;
 	_audioStream = 0;
 	_dirtyPalette = false;
@@ -123,6 +125,9 @@ bool RobotDecoder::loadStream(Common::SeekableReadStream *stream) {
 
 	readPaletteChunk(_header.paletteDataSize);
 	readFrameSizesChunk();
+	calculateVideoDimensions();
+	_surface->create(_width, _height, 1);
+
 	return true;
 }
 
@@ -218,31 +223,56 @@ void RobotDecoder::readFrameSizesChunk() {
 		_fileStream->seek((curPos & ~0x7ff) + 2048);
 }
 
+void RobotDecoder::calculateVideoDimensions() {
+	// This is an O(n) operation, as each frame has a different size.
+	// We need to know the actual frame size to have a constant video size.
+	uint32 pos = _fileStream->pos();
+	
+	for (uint32 curFrame = 0; curFrame < _header.frameCount; curFrame++) {
+		_fileStream->skip(4);
+		uint16 frameWidth = _fileStream->readUint16();
+		uint16 frameHeight = _fileStream->readUint16();
+		if (frameWidth > _width)
+			_width = frameWidth;
+		if (frameHeight > _height)
+			_height = frameHeight;
+		_fileStream->skip(_frameTotalSize[curFrame] - 8);
+	}
+
+	_fileStream->seek(pos);
+}
+
 const Graphics::Surface *RobotDecoder::decodeNextFrame() {
 	// Read frame image header (24 bytes)
 	_fileStream->skip(3);
 	byte frameScale = _fileStream->readByte();
 	uint16 frameWidth = _fileStream->readUint16();
 	uint16 frameHeight = _fileStream->readUint16();
-	_fileStream->skip(8); // x, y, width and height of the frame
+	_fileStream->skip(4); // unknown, almost always 0
+	uint16 frameX = _fileStream->readUint16();
+	uint16 frameY = _fileStream->readUint16();
 	uint16 compressedSize = _fileStream->readUint16();
 	uint16 frameFragments = _fileStream->readUint16();
 	_fileStream->skip(4); // unknown
-
 	uint32 decompressedSize = frameWidth * frameHeight * frameScale / 100;
-	_surface->free();
-	_surface->create(frameWidth, frameHeight, 1);
-	_surface->w = frameWidth * frameScale / 100;
+	// FIXME: A frame's height + position can go off limits... why? With the
+	// following, we cut the contents to fit the frame
+	uint16 scaledHeight = CLIP<uint16>(decompressedSize / frameWidth, 0, _height - frameY);
+	// FIXME: Same goes for the frame's width + position. In this case, we
+	// modify the position to fit the contents on screen.
+	if (frameWidth + frameX > _width)
+		frameX = _width - frameWidth;
+	assert (frameWidth + frameX <= _width && scaledHeight + frameY <= _height);
 
 	DecompressorLZS lzs;
+	byte *decompressedFrame = new byte[decompressedSize];
+	byte *outPtr = decompressedFrame;
 
 	if (_header.version == 4) {
 		// v4 has just the one fragment, it seems, and ignores the fragment count
 		Common::SeekableSubReadStream fragmentStream(_fileStream, _fileStream->pos(), _fileStream->pos() + compressedSize);
-		lzs.unpack(&fragmentStream, (byte *)_surface->pixels, compressedSize, decompressedSize);
+		lzs.unpack(&fragmentStream, outPtr, compressedSize, decompressedSize);
 	} else {
-		byte *outPtr = (byte *)_surface->pixels;
-
 		for (uint16 i = 0; i < frameFragments; ++i) {
 			uint32 compressedFragmentSize = _fileStream->readUint32();
 			uint32 decompressedFragmentSize = _fileStream->readUint32();
@@ -261,6 +291,24 @@ const Graphics::Surface *RobotDecoder::decodeNextFrame() {
 		}
 	}
 
+	// Copy over the decompressed frame
+	byte *inFrame = decompressedFrame;
+	byte *outFrame = (byte *)_surface->pixels;
+
+	// Black out the surface
+	memset(outFrame, 0, _width * _height);
+
+	// Move to the correct y coordinate
+	outFrame += _width * frameY;
+
+	for (uint16 y = 0; y < scaledHeight; y++) {
+		memcpy(outFrame + frameX, inFrame, frameWidth);
+		inFrame += frameWidth;
+		outFrame += _width;
+	}
+
+	delete[] decompressedFrame;
+
 	// +1 because we start with frame number -1
 	uint32 audioChunkSize = _frameTotalSize[_curFrame + 1] - (24 + compressedSize);
 
diff --git a/engines/sci/video/robot_decoder.h b/engines/sci/video/robot_decoder.h
index eb0a150c9d..b8ca0ee857 100644
--- a/engines/sci/video/robot_decoder.h
+++ b/engines/sci/video/robot_decoder.h
@@ -62,9 +62,8 @@ public:
 	void close();
 
 	bool isVideoLoaded() const { return _fileStream != 0; }
-	uint16 getWidth() const { assert(_surface); return _surface->w; }
-	uint16 getHeight() const { assert(_surface); return _surface->h; }
-	uint16 getPitch() const { assert(_surface); return _surface->pitch; }
+	uint16 getWidth() const { return _width; }
+	uint16 getHeight() const { return _height; }
 	uint32 getFrameCount() const { return _header.frameCount; }
 	const Graphics::Surface *decodeNextFrame();
 	Graphics::PixelFormat getPixelFormat() const { return Graphics::PixelFormat::createFormatCLUT8(); }
@@ -80,6 +79,7 @@ private:
 	void readHeaderChunk();
 	void readPaletteChunk(uint16 chunkSize);
 	void readFrameSizesChunk();
+	void calculateVideoDimensions();
 
 	void freeData();
 
@@ -89,6 +89,8 @@ private:
 
 	Common::SeekableSubReadStreamEndian *_fileStream;
 
+	uint16 _width;
+	uint16 _height;
 	uint32 *_frameTotalSize;
 	byte _palette[256 * 3];
 	bool _dirtyPalette;