GRAPHICS: Rewrite ImageDecoder to have an improved API

The new bitmap decoder class is based off the Mohawk one, and now has 8bpp decoding capability.

3 files changed, 300 insertions, 0 deletions

diff --git a/graphics/decoders/bmp.cpp b/graphics/decoders/bmp.cpp
new file mode 100644
index 0000000000..0d44881d7c
--- /dev/null
+++ b/graphics/decoders/bmp.cpp
@@ -0,0 +1,159 @@
+/* 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 "common/stream.h"
+#include "common/textconsole.h"
+
+#include "graphics/pixelformat.h"
+#include "graphics/surface.h"
+#include "graphics/decoders/bmp.h"
+
+namespace Graphics {
+
+BitmapDecoder::BitmapDecoder() {
+	_surface = 0;
+	_palette = 0;
+}
+
+BitmapDecoder::~BitmapDecoder() {
+	destroy();
+}
+
+void BitmapDecoder::destroy() {
+	if (_surface) {
+		_surface->free();
+		delete _surface; _surface = 0;
+	}
+
+	delete[] _palette; _palette = 0;
+}
+
+bool BitmapDecoder::loadStream(Common::SeekableReadStream &stream) {
+	destroy();
+
+	if (stream.readByte() != 'B')
+		return false;
+
+	if (stream.readByte() != 'M')
+		return false;
+
+	/* uint32 fileSize = */ stream.readUint32LE();
+	/* uint16 res1 = */ stream.readUint16LE();
+	/* uint16 res2 = */ stream.readUint16LE();
+	uint32 imageOffset = stream.readUint32LE();
+
+	uint32 infoSize = stream.readUint32LE();
+	if (infoSize != 40) {
+		warning("Only Windows v3 bitmaps are supported");
+		return false;
+	}
+
+	uint32 width = stream.readUint32LE();
+	int32 height = stream.readSint32LE();
+
+	if (width == 0 || height == 0)
+		return false;
+
+	if (height < 0) {
+		warning("Right-side up bitmaps not supported");
+		return false;
+	}
+
+	/* uint16 planes = */ stream.readUint16LE();
+	uint16 bitsPerPixel = stream.readUint16LE();
+
+	if (bitsPerPixel != 8 && bitsPerPixel != 24) {
+		warning("%dbpp bitmaps not supported", bitsPerPixel);
+		return false;
+	}
+
+	uint32 compression = stream.readUint32LE();
+
+	if (compression != 0) {
+		warning("Compressed bitmaps not supported");
+		return false;
+	}
+
+	/* uint32 imageSize = */ stream.readUint32LE();
+	/* uint32 pixelsPerMeterX = */ stream.readUint32LE();
+	/* uint32 pixelsPerMeterY = */ stream.readUint32LE();
+	uint32 colorsUsed = stream.readUint32LE();
+	/* uint32 colorsImportant = */ stream.readUint32LE();
+
+	if (colorsUsed == 0)
+		colorsUsed = 256;
+
+	if (bitsPerPixel == 8) {
+		// Read the palette
+		_palette = new byte[colorsUsed * 3];
+		for (uint16 i = 0; i < colorsUsed; i++) {
+			_palette[i * 3 + 2] = stream.readByte();
+			_palette[i * 3 + 1] = stream.readByte();
+			_palette[i * 3 + 0] = stream.readByte();
+			stream.readByte();
+		}
+	}
+
+	// Start us at the beginning of the image
+	stream.seek(imageOffset);
+
+	Graphics::PixelFormat format = Graphics::PixelFormat::createFormatCLUT8();
+
+	// BGRA for 24bpp
+	if (bitsPerPixel == 24)
+		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->pixels;
+
+		for (int32 i = 0; i < height; i++) {
+			stream.read(dst + (height - i - 1) * width, width);
+			stream.skip(extraDataLength);
+		}
+	} else {
+		byte *dst = (byte *)_surface->pixels + (height - 1) * _surface->pitch;
+
+		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;
+		}
+	}
+
+	return true;
+}
+
+} // End of namespace Graphics
diff --git a/graphics/decoders/bmp.h b/graphics/decoders/bmp.h
new file mode 100644
index 0000000000..e11b12fad6
--- /dev/null
+++ b/graphics/decoders/bmp.h
@@ -0,0 +1,56 @@
+/* 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 GRAPHICS_DECODERS_BMP_H
+#define GRAPHICS_DECODERS_BMP_H
+
+#include "common/scummsys.h"
+#include "common/str.h"
+#include "graphics/decoders/image_decoder.h"
+
+namespace Common{
+class SeekableReadStream;
+}
+
+namespace Graphics {
+
+struct PixelFormat;
+struct Surface;
+
+class BitmapDecoder : public ImageDecoder {
+public:
+	BitmapDecoder();
+	virtual ~BitmapDecoder();
+
+	// ImageDecoder API
+	void destroy();
+	virtual bool loadStream(Common::SeekableReadStream &stream);
+	virtual const Surface *getSurface() const { return _surface; }
+	virtual const byte *getPalette() { return _palette; }
+
+private:
+	Surface *_surface;
+	byte *_palette;
+};
+
+} // End of namespace Graphics
+
+#endif
diff --git a/graphics/decoders/image_decoder.h b/graphics/decoders/image_decoder.h
new file mode 100644
index 0000000000..e768f7f9a2
--- /dev/null
+++ b/graphics/decoders/image_decoder.h
@@ -0,0 +1,85 @@
+/* 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 GRAPHICS_DECODERS_IMAGEDECODER_H
+#define GRAPHICS_DECODERS_IMAGEDECODER_H
+
+#include "common/scummsys.h"
+#include "common/str.h"
+
+namespace Common{
+class SeekableReadStream;
+}
+
+namespace Graphics {
+
+struct PixelFormat;
+struct Surface;
+
+/**
+ * A representation of an image decoder that maintains ownership of the surface
+ * and palette it decodes to.
+ */
+class ImageDecoder {
+public:
+	virtual ~ImageDecoder() {}
+
+	/**
+	 * Load an image from the specified stream
+	 *
+	 * @param stream the input stream
+	 * @return whether loading the file succeeded
+	 * @see getSurface
+	 * @see getPalette
+	 */
+	virtual bool loadStream(Common::SeekableReadStream &stream) = 0;
+
+	/**
+	 * Destroy this decoder's surface and palette
+	 */
+	virtual void destroy() = 0;
+
+	/**
+	 * Get the decoded surface
+	 *
+	 * This surface is owned by this ImageDecoder and will remain valid
+	 * until destroy() or loadStream() is called, or until this ImageDecoder's
+	 * destructor is called.
+	 *
+	 * @return the decoded surface, or 0 if no surface is present
+	 */
+	virtual const Surface *getSurface() const = 0;
+
+	/**
+	 * Get the decoded palette
+	 *
+	 * This palette is owned by this ImageDecoder and will remain valid
+	 * until destroy() or loadStream() is called, or until this ImageDecoder's
+	 * destructor is called.
+	 *
+	 * @return the decoded palette, or 0 if no palette is present
+	 */
+	virtual const byte *getPalette() const { return 0; }
+};
+
+} // End of namespace Graphics
+
+#endif