truelight@4300: /* $Id$ */
truelight@4300: 
belugas@6449: /** @file bmp.cpp */
belugas@6449: 
truelight@4300: #include "stdafx.h"
truelight@4300: #include "bmp.h"
rubidium@6872: #include "core/bitmath_func.hpp"
rubidium@6872: #include "core/alloc_func.hpp"
truelight@4300: 
richk@6743: void BmpInitializeBuffer(BmpBuffer *buffer, FILE *file)
richk@6743: {
truelight@4300: 	buffer->pos      = -1;
truelight@4300: 	buffer->file     = file;
truelight@4300: 	buffer->read     = 0;
truelight@4300: 	buffer->real_pos = ftell(file);
truelight@4300: }
truelight@4300: 
truelight@4300: static inline void AdvanceBuffer(BmpBuffer *buffer)
truelight@4300: {
truelight@4321: 	buffer->read = (int)fread(buffer->data, 1, BMP_BUFFER_SIZE, buffer->file);
truelight@4300: 	buffer->pos  = 0;
truelight@4300: }
truelight@4300: 
truelight@4300: static inline bool EndOfBuffer(BmpBuffer *buffer)
truelight@4300: {
truelight@4300: 	if (buffer->pos == buffer->read || buffer->pos < 0) AdvanceBuffer(buffer);
truelight@4300: 	return buffer->pos == buffer->read;
truelight@4300: }
truelight@4300: 
truelight@4300: static inline byte ReadByte(BmpBuffer *buffer)
truelight@4300: {
truelight@4300: 	if (buffer->pos == buffer->read || buffer->pos < 0) AdvanceBuffer(buffer);
truelight@4300: 	buffer->real_pos++;
truelight@4300: 	return buffer->data[buffer->pos++];
truelight@4300: }
truelight@4300: 
truelight@4300: static inline uint16 ReadWord(BmpBuffer *buffer)
truelight@4300: {
truelight@4300: 	uint16 var = ReadByte(buffer);
truelight@4300: 	return var | (ReadByte(buffer) << 8);
truelight@4300: }
truelight@4300: 
truelight@4300: static inline uint32 ReadDword(BmpBuffer *buffer)
truelight@4300: {
truelight@4300: 	uint32 var = ReadWord(buffer);
truelight@4300: 	return var | (ReadWord(buffer) << 16);
truelight@4300: }
truelight@4300: 
truelight@4300: static inline void SkipBytes(BmpBuffer *buffer, int bytes)
truelight@4300: {
truelight@4300: 	int i;
truelight@4300: 	for (i = 0; i < bytes; i++) ReadByte(buffer);
truelight@4300: }
truelight@4300: 
truelight@4300: static inline void SetStreamOffset(BmpBuffer *buffer, int offset)
truelight@4300: {
truelight@4300: 	fseek(buffer->file, offset, SEEK_SET);
truelight@4300: 	buffer->pos = -1;
truelight@4300: 	buffer->real_pos = offset;
truelight@4300: 	AdvanceBuffer(buffer);
truelight@4300: }
truelight@4300: 
truelight@4300: /**
truelight@4300:  * Reads a 1 bpp uncompressed bitmap
truelight@4300:  * The bitmap is converted to a 8 bpp bitmap
truelight@4300:  */
truelight@4300: static inline bool BmpRead1(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
truelight@4300: {
truelight@4300: 	uint x, y, i;
truelight@4300: 	byte pad = GB(4 - info->width / 8, 0, 2);
truelight@4300: 	byte *pixel_row;
truelight@4300: 	byte b;
truelight@4300: 	for (y = info->height; y > 0; y--) {
truelight@4300: 		x = 0;
truelight@4300: 		pixel_row = &data->bitmap[(y - 1) * info->width];
truelight@4300: 		while (x < info->width) {
truelight@4300: 			if (EndOfBuffer(buffer)) return false; // the file is shorter than expected
truelight@4300: 			b = ReadByte(buffer);
truelight@4300: 			for (i = 8; i > 0; i--) {
truelight@4300: 				if (x < info->width) *pixel_row++ = GB(b, i - 1, 1);
truelight@4300: 				x++;
truelight@4300: 			}
truelight@4300: 		}
truelight@4300: 		/* Padding for 32 bit align */
truelight@4300: 		SkipBytes(buffer, pad);
truelight@4300: 	}
truelight@4300: 	return true;
truelight@4300: }
truelight@4300: 
truelight@4300: /**
truelight@4300:  * Reads a 4 bpp uncompressed bitmap
truelight@4300:  * The bitmap is converted to a 8 bpp bitmap
truelight@4300:  */
truelight@4300: static inline bool BmpRead4(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
truelight@4300: {
truelight@4300: 	uint x, y;
truelight@4300: 	byte pad = GB(4 - info->width / 2, 0, 2);
truelight@4300: 	byte *pixel_row;
truelight@4300: 	byte b;
truelight@4300: 	for (y = info->height; y > 0; y--) {
truelight@4300: 		x = 0;
truelight@4300: 		pixel_row = &data->bitmap[(y - 1) * info->width];
truelight@4300: 		while (x < info->width) {
truelight@4300: 			if (EndOfBuffer(buffer)) return false;  // the file is shorter than expected
truelight@4300: 			b = ReadByte(buffer);
truelight@4300: 			*pixel_row++ = GB(b, 4, 4);
truelight@4300: 			x++;
truelight@4300: 			if (x < info->width) {
truelight@4300: 				*pixel_row++ = GB(b, 0, 4);
truelight@4300: 				x++;
truelight@4300: 			}
truelight@4300: 		}
truelight@4300: 		/* Padding for 32 bit align */
truelight@4300: 		SkipBytes(buffer, pad);
truelight@4300: 	}
truelight@4300: 	return true;
truelight@4300: }
truelight@4300: 
truelight@4300: /**
truelight@4300:  * Reads a 4-bit RLE compressed bitmap
truelight@4300:  * The bitmap is converted to a 8 bpp bitmap
truelight@4300:  */
truelight@4300: static inline bool BmpRead4Rle(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
truelight@4300: {
truelight@4300: 	uint i;
truelight@4300: 	uint x = 0;
truelight@4300: 	uint y = info->height - 1;
truelight@4300: 	byte n, c, b;
truelight@4300: 	byte *pixel = &data->bitmap[y * info->width];
truelight@4300: 	while (y != 0 || x < info->width) {
truelight@4300: 		if (EndOfBuffer(buffer)) return false; // the file is shorter than expected
truelight@4300: 		n = ReadByte(buffer);
truelight@4300: 		c = ReadByte(buffer);
truelight@4300: 		if (n == 0) {
truelight@4300: 			switch (c) {
truelight@4300: 			case 0: // end of line
truelight@4300: 				x = 0;
truelight@4300: 				pixel = &data->bitmap[--y * info->width];
truelight@4300: 				break;
truelight@4300: 			case 1: // end of bitmap
truelight@4300: 				x = info->width;
truelight@4300: 				y = 0;
truelight@4300: 				pixel = NULL;
truelight@4300: 				break;
truelight@4300: 			case 2: // delta
truelight@4300: 				x += ReadByte(buffer);
truelight@4300: 				i = ReadByte(buffer);
truelight@4300: 				if (x >= info->width || (y == 0 && i > 0)) return false;
truelight@4300: 				y -= i;
truelight@4300: 				pixel = &data->bitmap[y * info->width + x];
truelight@4300: 				break;
truelight@4300: 			default: // uncompressed
truelight@4300: 				i = 0;
truelight@4300: 				while (i++ < c) {
truelight@4300: 					if (EndOfBuffer(buffer) || x >= info->width) return false;
truelight@4300: 					b = ReadByte(buffer);
truelight@4300: 					*pixel++ = GB(b, 4, 4);
truelight@4300: 					x++;
truelight@4300: 					if (x < info->width && i++ < c) {
truelight@4300: 						*pixel++ = GB(b, 0, 4);
truelight@4300: 						x++;
truelight@4300: 					}
truelight@4300: 				}
truelight@4300: 				/* Padding for 16 bit align */
truelight@4300: 				SkipBytes(buffer, ((c + 1) / 2) % 2);
truelight@4300: 				break;
truelight@4300: 			}
truelight@4300: 		} else {
truelight@4300: 			i = 0;
truelight@4300: 			while (i++ < n) {
truelight@4300: 				if (EndOfBuffer(buffer) || x >= info->width) return false;
truelight@4300: 				*pixel++ = GB(c, 4, 4);
truelight@4300: 				x++;
truelight@4300: 				if (x < info->width && i++ < n) {
truelight@4300: 					*pixel++ = GB(c, 0, 4);
truelight@4300: 					x++;
truelight@4300: 				}
truelight@4300: 			}
truelight@4300: 		}
truelight@4300: 	}
truelight@4300: 	return true;
truelight@4300: }
truelight@4300: 
truelight@4300: /**
truelight@4300:  * Reads a 8 bpp bitmap
truelight@4300:  */
truelight@4300: static inline bool BmpRead8(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
truelight@4300: {
truelight@4300: 	uint i;
truelight@4300: 	uint y;
truelight@4300: 	byte pad = GB(4 - info->width, 0, 2);
truelight@4300: 	byte *pixel;
truelight@4300: 	for (y = info->height; y > 0; y--) {
truelight@4300: 		if (EndOfBuffer(buffer)) return false; // the file is shorter than expected
truelight@4300: 		pixel = &data->bitmap[(y - 1) * info->width];
truelight@4300: 		for (i = 0; i < info->width; i++) *pixel++ = ReadByte(buffer);
truelight@4300: 		/* Padding for 32 bit align */
truelight@4300: 		SkipBytes(buffer, pad);
truelight@4300: 	}
truelight@4300: 	return true;
truelight@4300: }
truelight@4300: 
truelight@4300: /**
truelight@4300:  * Reads a 8-bit RLE compressed bpp bitmap
truelight@4300:  */
truelight@4300: static inline bool BmpRead8Rle(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
truelight@4300: {
truelight@4300: 	uint i;
truelight@4300: 	uint x = 0;
truelight@4300: 	uint y = info->height - 1;
truelight@4300: 	byte n, c;
truelight@4300: 	byte *pixel = &data->bitmap[y * info->width];
truelight@4300: 	while (y != 0 || x < info->width) {
truelight@4300: 		if (EndOfBuffer(buffer)) return false; // the file is shorter than expected
truelight@4300: 		n = ReadByte(buffer);
truelight@4300: 		c = ReadByte(buffer);
truelight@4300: 		if (n == 0) {
truelight@4300: 			switch (c) {
truelight@4300: 			case 0: // end of line
truelight@4300: 				x = 0;
truelight@4300: 				pixel = &data->bitmap[--y * info->width];
truelight@4300: 				break;
truelight@4300: 			case 1: // end of bitmap
truelight@4300: 				x = info->width;
truelight@4300: 				y = 0;
truelight@4300: 				pixel = NULL;
truelight@4300: 				break;
truelight@4300: 			case 2: // delta
truelight@4300: 				x += ReadByte(buffer);
truelight@4300: 				i = ReadByte(buffer);
truelight@4300: 				if (x >= info->width || (y == 0 && i > 0)) return false;
truelight@4300: 				y -= i;
truelight@4300: 				pixel = &data->bitmap[y * info->width + x];
truelight@4300: 				break;
truelight@4300: 			default: // uncompressed
truelight@4300: 				if ((x += c) > info->width) return false;
truelight@4300: 				for (i = 0; i < c; i++) *pixel++ = ReadByte(buffer);
truelight@4300: 				/* Padding for 16 bit align */
truelight@4300: 				SkipBytes(buffer, c % 2);
truelight@4300: 				break;
truelight@4300: 			}
truelight@4300: 		} else {
truelight@4300: 			for (i = 0; i < n; i++) {
truelight@4300: 				if (x >= info->width) return false;
truelight@4300: 				*pixel++ = c;
truelight@4300: 				x++;
truelight@4300: 			}
truelight@4300: 		}
truelight@4300: 	}
truelight@4300: 	return true;
truelight@4300: }
truelight@4300: 
truelight@4300: /**
truelight@4300:  * Reads a 24 bpp uncompressed bitmap
truelight@4300:  */
truelight@4300: static inline bool BmpRead24(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
truelight@4300: {
truelight@4300: 	uint x, y;
truelight@4300: 	byte pad = GB(4 - info->width * 3, 0, 2);
truelight@4300: 	byte *pixel_row;
truelight@4300: 	for (y = info->height; y > 0; y--) {
truelight@4300: 		pixel_row = &data->bitmap[(y - 1) * info->width * 3];
truelight@4300: 		for (x = 0; x < info->width; x++) {
truelight@4300: 			if (EndOfBuffer(buffer)) return false; // the file is shorter than expected
truelight@4300: 			*(pixel_row + 2) = ReadByte(buffer); // green
truelight@4300: 			*(pixel_row + 1) = ReadByte(buffer); // blue
truelight@4300: 			*pixel_row       = ReadByte(buffer); // red
truelight@4300: 			pixel_row += 3;
truelight@4300: 		}
truelight@4300: 		/* Padding for 32 bit align */
truelight@4300: 		SkipBytes(buffer, pad);
truelight@4300: 	}
truelight@4300: 	return true;
truelight@4300: }
truelight@4300: 
truelight@4300: /*
truelight@4300:  * Reads bitmap headers, and palette (if any)
truelight@4300:  */
truelight@4300: bool BmpReadHeader(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
truelight@4300: {
truelight@4300: 	uint32 header_size;
truelight@4300: 	assert(info != NULL);
truelight@4300: 
truelight@4300: 	/* Reading BMP header */
truelight@4300: 	if (ReadWord(buffer) != 0x4D42) return false; // signature should be 'BM'
truelight@4300: 	SkipBytes(buffer, 8); // skip file size and reserved
truelight@4300: 	info->offset = ReadDword(buffer);
truelight@4300: 
truelight@4300: 	/* Reading info header */
truelight@4300: 	header_size = ReadDword(buffer);
truelight@4300: 	if (header_size < 12) return false; // info header should be at least 12 bytes long
truelight@4300: 
truelight@4300: 	info->os2_bmp = (header_size == 12); // OS/2 1.x or windows 2.x info header is 12 bytes long
truelight@4300: 
truelight@4300: 	if (info->os2_bmp) {
truelight@4300: 		info->width = ReadWord(buffer);
truelight@4300: 		info->height = ReadWord(buffer);
truelight@4300: 		header_size -= 8;
truelight@4300: 	} else {
truelight@4300: 		info->width = ReadDword(buffer);
truelight@4300: 		info->height = ReadDword(buffer);
truelight@4300: 		header_size -= 12;
truelight@4300: 	}
truelight@4300: 
truelight@4300: 	if (ReadWord(buffer) != 1) return false; // BMP can have only 1 plane
truelight@4300: 
truelight@4300: 	info->bpp = ReadWord(buffer);
truelight@4300: 	if (info->bpp != 1 && info->bpp != 4 && info->bpp != 8 && info->bpp != 24) {
truelight@4300: 		/* Only 1 bpp, 4 bpp, 8bpp and 24 bpp bitmaps are supported */
truelight@4300: 		return false;
truelight@4300: 	}
truelight@4300: 
truelight@4300: 	/* Reads compression method if available in info header*/
truelight@4300: 	if ((header_size -= 4) >= 4) {
truelight@4300: 		info->compression = ReadDword(buffer);
truelight@4300: 		header_size -= 4;
truelight@4300: 	}
truelight@4300: 
truelight@4300: 	/* Only 4-bit and 8-bit rle compression is supported */
truelight@4300: 	if (info->compression > 2 || (info->compression > 0 && !(info->bpp == 4 || info->bpp == 8))) return false;
truelight@4300: 
truelight@4300: 	if (info->bpp <= 8) {
truelight@4300: 		uint i;
truelight@4300: 
truelight@4300: 		/* Reads number of colors if available in info header */
truelight@4300: 		if (header_size >= 16) {
truelight@4300: 			SkipBytes(buffer, 12);                  // skip image size and resolution
truelight@4300: 			info->palette_size = ReadDword(buffer); // number of colors in palette
truelight@4300: 			SkipBytes(buffer, header_size - 16);    // skip the end of info header
truelight@4300: 		}
truelight@4300: 		if (info->palette_size == 0) info->palette_size = 1 << info->bpp;
truelight@4300: 
KUDr@5860: 		data->palette = CallocT<Colour>(info->palette_size);
truelight@4300: 		if (data->palette == NULL) return false;
truelight@4300: 
truelight@4300: 		for (i = 0; i < info->palette_size; i++) {
truelight@4300: 			data->palette[i].b = ReadByte(buffer);
truelight@4300: 			data->palette[i].g = ReadByte(buffer);
truelight@4300: 			data->palette[i].r = ReadByte(buffer);
truelight@4300: 			if (!info->os2_bmp) SkipBytes(buffer, 1); // unused
truelight@4300: 		}
truelight@4300: 	}
truelight@4300: 
truelight@4300: 	return buffer->real_pos <= info->offset;
truelight@4300: }
truelight@4300: 
truelight@4300: /*
truelight@4300:  * Reads the bitmap
truelight@4300:  * 1 bpp and 4 bpp bitmaps are converted to 8 bpp bitmaps
truelight@4300:  */
truelight@4300: bool BmpReadBitmap(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
truelight@4300: {
truelight@4300: 	assert(info != NULL && data != NULL);
truelight@4300: 
rubidium@6872: 	data->bitmap = CallocT<byte>(info->width * info->height * ((info->bpp == 24) ? 3 : 1));
truelight@4300: 	if (data->bitmap == NULL) return false;
truelight@4300: 
truelight@4300: 	/* Load image */
truelight@4300: 	SetStreamOffset(buffer, info->offset);
truelight@4300: 	switch (info->compression) {
truelight@4300: 	case 0: // no compression
truelight@4300: 		switch (info->bpp) {
truelight@4300: 		case 1:  return BmpRead1(buffer, info, data);
truelight@4300: 		case 4:  return BmpRead4(buffer, info, data);
truelight@4300: 		case 8:  return BmpRead8(buffer, info, data);
truelight@4300: 		case 24: return BmpRead24(buffer, info, data);
truelight@4300: 		default: NOT_REACHED(); return false;
truelight@4300: 		}
truelight@4300: 	case 1:  return BmpRead8Rle(buffer, info, data); // 8-bit RLE compression
truelight@4300: 	case 2:  return BmpRead4Rle(buffer, info, data); // 4-bit RLE compression
truelight@4300: 	default: NOT_REACHED(); return false;
truelight@4300: 	}
truelight@4300: }
truelight@4300: 
truelight@4300: void BmpDestroyData(BmpData *data)
truelight@4300: {
truelight@4300: 	assert(data != NULL);
truelight@4300: 	free(data->palette);
truelight@4300: 	free(data->bitmap);
truelight@4300: }