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Diffstat (limited to 'graphics/png.h')
| -rw-r--r-- | graphics/png.h | 168 |
1 files changed, 0 insertions, 168 deletions
diff --git a/graphics/png.h b/graphics/png.h deleted file mode 100644 index 078c76fc6b..0000000000 --- a/graphics/png.h +++ /dev/null @@ -1,168 +0,0 @@ -/* 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. - * - */ - -/* - * PNG decoder used in engines: - * - sword25 - * Dependencies: - * - zlib - */ - -#ifndef GRAPHICS_PNG_H -#define GRAPHICS_PNG_H - -// PNG decoder, based on the W3C specs: -// http://www.w3.org/TR/PNG/ -// Parts of the code have been adapted from LodePNG, by Lode Vandevenne: -// http://members.gamedev.net/lode/projects/LodePNG/ - -// All the numbers are BE: http://www.w3.org/TR/PNG/#7Integers-and-byte-order - -// Note: At the moment, this decoder only supports non-interlaced images, and -// does not support truecolor/grayscale images with 16bit depth. -// -// Theoretically, interlaced images shouldn't be needed for games, as -// interlacing is only useful for images in websites. -// -// PNG images with 16bit depth (i.e. 48bit images) are quite rare, and can -// theoretically contain more than 16.7 millions of colors (the so-called "deep -// color" representation). In essence, each of the R, G, B and A components in -// them is specified with 2 bytes, instead of 1. However, the PNG specification -// always refers to color components with 1 byte each, so this part of the spec -// is a bit unclear. For now, these won't be supported, until a suitable sample -// is found. - -#include "common/scummsys.h" -#include "common/textconsole.h" - -namespace Common { -class SeekableReadStream; -} - -namespace Graphics { - -struct Surface; - -enum PNGColorType { - kGrayScale = 0, // bit depths: 1, 2, 4, 8, 16 - kTrueColor = 2, // bit depths: 8, 16 - kIndexed = 3, // bit depths: 1, 2, 4, 8 - kGrayScaleWithAlpha = 4, // bit depths: 8, 16 - kTrueColorWithAlpha = 6 // bit depths: 8, 16 -}; - -enum PNGInterlaceType { - kNonInterlaced = 0, - kInterlaced = 1 -}; - -struct PNGHeader { - uint32 width; - uint32 height; - byte bitDepth; - PNGColorType colorType; - byte compressionMethod; - byte filterMethod; - PNGInterlaceType interlaceType; -}; - -struct PixelFormat; - -class PNG { -public: - PNG(); - ~PNG(); - - /** - * Reads a PNG image from the specified stream - */ - bool read(Common::SeekableReadStream *str); - - /** - * Returns the information obtained from the PNG header. - */ - PNGHeader getHeader() const { return _header; } - - /** - * Returns the PNG image, formatted for the specified pixel format. - */ - Graphics::Surface *getSurface(const PixelFormat &format); - - /** - * Returns the indexed PNG8 image. Used for PNGs with an indexed 256 color - * palette, when they're shown on an 8-bit color screen, as no translation - * is taking place. - */ - Graphics::Surface *getIndexedSurface() { - if (_header.colorType != kIndexed) - error("Indexed surface requested for a non-indexed PNG"); - return _unfilteredSurface; - } - - /** - * Returns the palette of the specified PNG8 image, given a pointer to - * an RGBA palette array (4 x 256). - */ - void getPalette(byte *palette, uint16 &entries) { - if (_header.colorType != kIndexed) - error("Palette requested for a non-indexed PNG"); - for (int i = 0; i < 256; i++) { - palette[0 + i * 4] = _palette[0 + i * 4]; // R - palette[1 + i * 4] = _palette[1 + i * 4]; // G - palette[2 + i * 4] = _palette[2 + i * 4]; // B - palette[3 + i * 4] = _palette[3 + i * 4]; // A - } - entries = _paletteEntries; - } - -private: - void readHeaderChunk(); - byte getNumColorChannels(); - - void readPaletteChunk(); - void readTransparencyChunk(uint32 chunkLength); - - void constructImage(); - void unfilterScanLine(byte *dest, const byte *scanLine, const byte *prevLine, uint16 byteWidth, byte filterType, uint16 length); - byte paethPredictor(int16 a, int16 b, int16 c); - - // The original file stream - Common::SeekableReadStream *_stream; - // The unzipped image data stream - Common::SeekableReadStream *_imageData; - - PNGHeader _header; - - byte _palette[256 * 4]; // RGBA - uint16 _paletteEntries; - uint16 _transparentColor[3]; - bool _transparentColorSpecified; - - byte *_compressedBuffer; - uint32 _compressedBufferSize; - - Graphics::Surface *_unfilteredSurface; -}; - -} // End of Graphics namespace - -#endif // GRAPHICS_PNG_H |