IMAGE: Split raw bitmap decoding into a Codec

image/bmp.cpp

@@ -23,9 +23,11 @@
 #include "image/bmp.h"
 
 #include "common/stream.h"
+#include "common/substream.h"
 #include "common/textconsole.h"
 #include "graphics/pixelformat.h"
 #include "graphics/surface.h"
+#include "image/codecs/bmp_raw.h"
 
 namespace Image {
 
@@ -33,6 +35,7 @@ BitmapDecoder::BitmapDecoder() {
 	_surface = 0;
 	_palette = 0;
 	_paletteColorCount = 0;
+	_codec = 0;
 }
 
 BitmapDecoder::~BitmapDecoder() {
@@ -40,13 +43,15 @@ BitmapDecoder::~BitmapDecoder() {
 }
 
 void BitmapDecoder::destroy() {
-	if (_surface) {
+	_surface = 0;
-		_surface->free();
+
-		delete _surface; _surface = 0;
+	delete[] _palette;
-	}
+	_palette = 0;
 
-	delete[] _palette; _palette = 0;
 	_paletteColorCount = 0;
+
+	delete _codec;
+	_codec = 0;
 }
 
 bool BitmapDecoder::loadStream(Common::SeekableReadStream &stream) {
@@ -95,7 +100,7 @@ bool BitmapDecoder::loadStream(Common::SeekableReadStream &stream) {
 		return false;
 	}
 
-	/* uint32 imageSize = */ stream.readUint32LE();
+	uint32 imageSize = stream.readUint32LE();
 	/* uint32 pixelsPerMeterX = */ stream.readUint32LE();
 	/* uint32 pixelsPerMeterY = */ stream.readUint32LE();
 	_paletteColorCount = stream.readUint32LE();
@@ -115,67 +120,12 @@ bool BitmapDecoder::loadStream(Common::SeekableReadStream &stream) {
 		}
 	}
 
-	// Start us at the beginning of the image
+	// Grab the frame data
-	stream.seek(imageOffset);
+	Common::SeekableSubReadStream subStream(&stream, imageOffset, imageOffset + imageSize);
 
-	Graphics::PixelFormat format = Graphics::PixelFormat::createFormatCLUT8();
+	// We only support raw bitmaps for now
-
+	_codec = new BitmapRawDecoder(width, height, bitsPerPixel);
-	// BGRA for 24bpp and 32 bpp
+	_surface = _codec->decodeFrame(subStream);
-	if (bitsPerPixel == 24 || bitsPerPixel == 32)
-		format = Graphics::PixelFormat(4, 8, 8, 8, 8, 8, 16, 24, 0);
-
-	_surface = new Graphics::Surface();
-	_surface->create(width, height, format);
-
-	int srcPitch = width * (bitsPerPixel >> 3);
-	const int extraDataLength = (srcPitch % 4) ? 4 - (srcPitch % 4) : 0;
-
-	if (bitsPerPixel == 8) {
-		byte *dst = (byte *)_surface->getPixels();
-
-		for (int32 i = 0; i < height; i++) {
-			stream.read(dst + (height - i - 1) * width, width);
-			stream.skip(extraDataLength);
-		}
-	} else if (bitsPerPixel == 24) {
-		byte *dst = (byte *)_surface->getBasePtr(0, height - 1);
-
-		for (int32 i = 0; i < height; i++) {
-			for (uint32 j = 0; j < width; j++) {
-				byte b = stream.readByte();
-				byte g = stream.readByte();
-				byte r = stream.readByte();
-				uint32 color = format.RGBToColor(r, g, b);
-
-				*((uint32 *)dst) = color;
-				dst += format.bytesPerPixel;
-			}
-
-			stream.skip(extraDataLength);
-			dst -= _surface->pitch * 2;
-		}
-	} else { // 32 bpp
-		byte *dst = (byte *)_surface->getBasePtr(0, height - 1);
-
-		for (int32 i = 0; i < height; i++) {
-			for (uint32 j = 0; j < width; j++) {
-				byte b = stream.readByte();
-				byte g = stream.readByte();
-				byte r = stream.readByte();
-				// Ignore the last byte, as in v3 it is unused
-				// and should thus NOT be used as alpha.
-				// ref: http://msdn.microsoft.com/en-us/library/windows/desktop/dd183376%28v=vs.85%29.aspx
-				stream.readByte();
-				uint32 color = format.RGBToColor(r, g, b);
-
-				*((uint32 *)dst) = color;
-				dst += format.bytesPerPixel;
-			}
-
-			stream.skip(extraDataLength);
-			dst -= _surface->pitch * 2;
-		}
-	}
 
 	return true;
 }

image/bmp.h

@@ -45,6 +45,8 @@ struct Surface;
 
 namespace Image {
 
+class Codec;
+
 class BitmapDecoder : public ImageDecoder {
 public:
 	BitmapDecoder();
@@ -58,7 +60,8 @@ public:
 	uint16 getPaletteColorCount() const { return _paletteColorCount; }
 
 private:
-	Graphics::Surface *_surface;
+	Codec *_codec;
+	const Graphics::Surface *_surface;
 	byte *_palette;
 	uint16 _paletteColorCount;
 };

image/codecs/bmp_raw.cpp

@@ -0,0 +1,113 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "image/codecs/bmp_raw.h"
+
+#include "common/stream.h"
+#include "common/textconsole.h"
+#include "graphics/surface.h"
+
+namespace Image {
+
+BitmapRawDecoder::BitmapRawDecoder(int width, int height, int bitsPerPixel) : Codec(),
+		_surface(0), _width(width), _height(height), _bitsPerPixel(bitsPerPixel) {
+}
+
+BitmapRawDecoder::~BitmapRawDecoder() {
+	if (_surface) {
+		_surface->free();
+		delete _surface;
+	}
+}
+
+const Graphics::Surface *BitmapRawDecoder::decodeFrame(Common::SeekableReadStream &stream) {
+	Graphics::PixelFormat format = getPixelFormat();
+
+	_surface = new Graphics::Surface();
+	_surface->create(_width, _height, format);
+
+	int srcPitch = _width * (_bitsPerPixel >> 3);
+	const int extraDataLength = (srcPitch % 4) ? 4 - (srcPitch % 4) : 0;
+
+	if (_bitsPerPixel == 8) {
+		byte *dst = (byte *)_surface->getPixels();
+
+		for (int i = 0; i < _height; i++) {
+			stream.read(dst + (_height - i - 1) * _width, _width);
+			stream.skip(extraDataLength);
+		}
+	} else if (_bitsPerPixel == 24) {
+		byte *dst = (byte *)_surface->getBasePtr(0, _height - 1);
+
+		for (int i = 0; i < _height; i++) {
+			for (int j = 0; j < _width; j++) {
+				byte b = stream.readByte();
+				byte g = stream.readByte();
+				byte r = stream.readByte();
+				uint32 color = format.RGBToColor(r, g, b);
+
+				*((uint32 *)dst) = color;
+				dst += format.bytesPerPixel;
+			}
+
+			stream.skip(extraDataLength);
+			dst -= _surface->pitch * 2;
+		}
+	} else { // 32 bpp
+		byte *dst = (byte *)_surface->getBasePtr(0, _height - 1);
+
+		for (int i = 0; i < _height; i++) {
+			for (int j = 0; j < _width; j++) {
+				byte b = stream.readByte();
+				byte g = stream.readByte();
+				byte r = stream.readByte();
+				// Ignore the last byte, as in v3 it is unused
+				// and should thus NOT be used as alpha.
+				// ref: http://msdn.microsoft.com/en-us/library/windows/desktop/dd183376%28v=vs.85%29.aspx
+				stream.readByte();
+				uint32 color = format.RGBToColor(r, g, b);
+
+				*((uint32 *)dst) = color;
+				dst += format.bytesPerPixel;
+			}
+
+			stream.skip(extraDataLength);
+			dst -= _surface->pitch * 2;
+		}
+	}
+
+	return _surface;
+}
+
+Graphics::PixelFormat BitmapRawDecoder::getPixelFormat() const {
+	switch (_bitsPerPixel) {
+	case 8:
+		return Graphics::PixelFormat::createFormatCLUT8();
+	case 24:
+	case 32:
+		return Graphics::PixelFormat(4, 8, 8, 8, 8, 8, 16, 24, 0);
+	}
+
+	error("Unhandled BMP raw %dbpp", _bitsPerPixel);
+}
+
+} // End of namespace Image

image/codecs/bmp_raw.h

@@ -0,0 +1,52 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef IMAGE_CODECS_BMP_RAW_H
+#define IMAGE_CODECS_BMP_RAW_H
+
+#include "image/codecs/codec.h"
+
+namespace Image {
+
+/**
+ * Bitmap raw image decoder.
+ *
+ * Used in image:
+ *  - BitmapDecoder
+ */
+class BitmapRawDecoder : public Codec {
+public:
+	BitmapRawDecoder(int width, int height, int bitsPerPixel);
+	~BitmapRawDecoder();
+
+	const Graphics::Surface *decodeFrame(Common::SeekableReadStream &stream);
+	Graphics::PixelFormat getPixelFormat() const;
+
+private:
+	Graphics::Surface *_surface;
+	int _width, _height;
+	int _bitsPerPixel;
+};
+
+} // End of namespace Image
+
+#endif

image/module.mk

@@ -8,6 +8,7 @@ MODULE_OBJS := \
 	pict.o \
 	png.o \
 	tga.o \
+	codecs/bmp_raw.o \
 	codecs/cdtoons.o \
 	codecs/cinepak.o \
 	codecs/indeo3.o \