(svn r10775) [NoAI] -Sync: with trunk r10535:r10774.
/* $Id$ */
/** @file bmp.cpp */
#include "stdafx.h"
#include "openttd.h"
#include "gfx.h"
#include "bmp.h"
#include "macros.h"
#include "helpers.hpp"
void BmpInitializeBuffer(BmpBuffer *buffer, FILE *file)
{
buffer->pos = -1;
buffer->file = file;
buffer->read = 0;
buffer->real_pos = ftell(file);
}
static inline void AdvanceBuffer(BmpBuffer *buffer)
{
buffer->read = (int)fread(buffer->data, 1, BMP_BUFFER_SIZE, buffer->file);
buffer->pos = 0;
}
static inline bool EndOfBuffer(BmpBuffer *buffer)
{
if (buffer->pos == buffer->read || buffer->pos < 0) AdvanceBuffer(buffer);
return buffer->pos == buffer->read;
}
static inline byte ReadByte(BmpBuffer *buffer)
{
if (buffer->pos == buffer->read || buffer->pos < 0) AdvanceBuffer(buffer);
buffer->real_pos++;
return buffer->data[buffer->pos++];
}
static inline uint16 ReadWord(BmpBuffer *buffer)
{
uint16 var = ReadByte(buffer);
return var | (ReadByte(buffer) << 8);
}
static inline uint32 ReadDword(BmpBuffer *buffer)
{
uint32 var = ReadWord(buffer);
return var | (ReadWord(buffer) << 16);
}
static inline void SkipBytes(BmpBuffer *buffer, int bytes)
{
int i;
for (i = 0; i < bytes; i++) ReadByte(buffer);
}
static inline void SetStreamOffset(BmpBuffer *buffer, int offset)
{
fseek(buffer->file, offset, SEEK_SET);
buffer->pos = -1;
buffer->real_pos = offset;
AdvanceBuffer(buffer);
}
/**
* Reads a 1 bpp uncompressed bitmap
* The bitmap is converted to a 8 bpp bitmap
*/
static inline bool BmpRead1(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
{
uint x, y, i;
byte pad = GB(4 - info->width / 8, 0, 2);
byte *pixel_row;
byte b;
for (y = info->height; y > 0; y--) {
x = 0;
pixel_row = &data->bitmap[(y - 1) * info->width];
while (x < info->width) {
if (EndOfBuffer(buffer)) return false; // the file is shorter than expected
b = ReadByte(buffer);
for (i = 8; i > 0; i--) {
if (x < info->width) *pixel_row++ = GB(b, i - 1, 1);
x++;
}
}
/* Padding for 32 bit align */
SkipBytes(buffer, pad);
}
return true;
}
/**
* Reads a 4 bpp uncompressed bitmap
* The bitmap is converted to a 8 bpp bitmap
*/
static inline bool BmpRead4(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
{
uint x, y;
byte pad = GB(4 - info->width / 2, 0, 2);
byte *pixel_row;
byte b;
for (y = info->height; y > 0; y--) {
x = 0;
pixel_row = &data->bitmap[(y - 1) * info->width];
while (x < info->width) {
if (EndOfBuffer(buffer)) return false; // the file is shorter than expected
b = ReadByte(buffer);
*pixel_row++ = GB(b, 4, 4);
x++;
if (x < info->width) {
*pixel_row++ = GB(b, 0, 4);
x++;
}
}
/* Padding for 32 bit align */
SkipBytes(buffer, pad);
}
return true;
}
/**
* Reads a 4-bit RLE compressed bitmap
* The bitmap is converted to a 8 bpp bitmap
*/
static inline bool BmpRead4Rle(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
{
uint i;
uint x = 0;
uint y = info->height - 1;
byte n, c, b;
byte *pixel = &data->bitmap[y * info->width];
while (y != 0 || x < info->width) {
if (EndOfBuffer(buffer)) return false; // the file is shorter than expected
n = ReadByte(buffer);
c = ReadByte(buffer);
if (n == 0) {
switch (c) {
case 0: // end of line
x = 0;
pixel = &data->bitmap[--y * info->width];
break;
case 1: // end of bitmap
x = info->width;
y = 0;
pixel = NULL;
break;
case 2: // delta
x += ReadByte(buffer);
i = ReadByte(buffer);
if (x >= info->width || (y == 0 && i > 0)) return false;
y -= i;
pixel = &data->bitmap[y * info->width + x];
break;
default: // uncompressed
i = 0;
while (i++ < c) {
if (EndOfBuffer(buffer) || x >= info->width) return false;
b = ReadByte(buffer);
*pixel++ = GB(b, 4, 4);
x++;
if (x < info->width && i++ < c) {
*pixel++ = GB(b, 0, 4);
x++;
}
}
/* Padding for 16 bit align */
SkipBytes(buffer, ((c + 1) / 2) % 2);
break;
}
} else {
i = 0;
while (i++ < n) {
if (EndOfBuffer(buffer) || x >= info->width) return false;
*pixel++ = GB(c, 4, 4);
x++;
if (x < info->width && i++ < n) {
*pixel++ = GB(c, 0, 4);
x++;
}
}
}
}
return true;
}
/**
* Reads a 8 bpp bitmap
*/
static inline bool BmpRead8(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
{
uint i;
uint y;
byte pad = GB(4 - info->width, 0, 2);
byte *pixel;
for (y = info->height; y > 0; y--) {
if (EndOfBuffer(buffer)) return false; // the file is shorter than expected
pixel = &data->bitmap[(y - 1) * info->width];
for (i = 0; i < info->width; i++) *pixel++ = ReadByte(buffer);
/* Padding for 32 bit align */
SkipBytes(buffer, pad);
}
return true;
}
/**
* Reads a 8-bit RLE compressed bpp bitmap
*/
static inline bool BmpRead8Rle(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
{
uint i;
uint x = 0;
uint y = info->height - 1;
byte n, c;
byte *pixel = &data->bitmap[y * info->width];
while (y != 0 || x < info->width) {
if (EndOfBuffer(buffer)) return false; // the file is shorter than expected
n = ReadByte(buffer);
c = ReadByte(buffer);
if (n == 0) {
switch (c) {
case 0: // end of line
x = 0;
pixel = &data->bitmap[--y * info->width];
break;
case 1: // end of bitmap
x = info->width;
y = 0;
pixel = NULL;
break;
case 2: // delta
x += ReadByte(buffer);
i = ReadByte(buffer);
if (x >= info->width || (y == 0 && i > 0)) return false;
y -= i;
pixel = &data->bitmap[y * info->width + x];
break;
default: // uncompressed
if ((x += c) > info->width) return false;
for (i = 0; i < c; i++) *pixel++ = ReadByte(buffer);
/* Padding for 16 bit align */
SkipBytes(buffer, c % 2);
break;
}
} else {
for (i = 0; i < n; i++) {
if (x >= info->width) return false;
*pixel++ = c;
x++;
}
}
}
return true;
}
/**
* Reads a 24 bpp uncompressed bitmap
*/
static inline bool BmpRead24(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
{
uint x, y;
byte pad = GB(4 - info->width * 3, 0, 2);
byte *pixel_row;
for (y = info->height; y > 0; y--) {
pixel_row = &data->bitmap[(y - 1) * info->width * 3];
for (x = 0; x < info->width; x++) {
if (EndOfBuffer(buffer)) return false; // the file is shorter than expected
*(pixel_row + 2) = ReadByte(buffer); // green
*(pixel_row + 1) = ReadByte(buffer); // blue
*pixel_row = ReadByte(buffer); // red
pixel_row += 3;
}
/* Padding for 32 bit align */
SkipBytes(buffer, pad);
}
return true;
}
/*
* Reads bitmap headers, and palette (if any)
*/
bool BmpReadHeader(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
{
uint32 header_size;
assert(info != NULL);
/* Reading BMP header */
if (ReadWord(buffer) != 0x4D42) return false; // signature should be 'BM'
SkipBytes(buffer, 8); // skip file size and reserved
info->offset = ReadDword(buffer);
/* Reading info header */
header_size = ReadDword(buffer);
if (header_size < 12) return false; // info header should be at least 12 bytes long
info->os2_bmp = (header_size == 12); // OS/2 1.x or windows 2.x info header is 12 bytes long
if (info->os2_bmp) {
info->width = ReadWord(buffer);
info->height = ReadWord(buffer);
header_size -= 8;
} else {
info->width = ReadDword(buffer);
info->height = ReadDword(buffer);
header_size -= 12;
}
if (ReadWord(buffer) != 1) return false; // BMP can have only 1 plane
info->bpp = ReadWord(buffer);
if (info->bpp != 1 && info->bpp != 4 && info->bpp != 8 && info->bpp != 24) {
/* Only 1 bpp, 4 bpp, 8bpp and 24 bpp bitmaps are supported */
return false;
}
/* Reads compression method if available in info header*/
if ((header_size -= 4) >= 4) {
info->compression = ReadDword(buffer);
header_size -= 4;
}
/* Only 4-bit and 8-bit rle compression is supported */
if (info->compression > 2 || (info->compression > 0 && !(info->bpp == 4 || info->bpp == 8))) return false;
if (info->bpp <= 8) {
uint i;
/* Reads number of colors if available in info header */
if (header_size >= 16) {
SkipBytes(buffer, 12); // skip image size and resolution
info->palette_size = ReadDword(buffer); // number of colors in palette
SkipBytes(buffer, header_size - 16); // skip the end of info header
}
if (info->palette_size == 0) info->palette_size = 1 << info->bpp;
data->palette = CallocT<Colour>(info->palette_size);
if (data->palette == NULL) return false;
for (i = 0; i < info->palette_size; i++) {
data->palette[i].b = ReadByte(buffer);
data->palette[i].g = ReadByte(buffer);
data->palette[i].r = ReadByte(buffer);
if (!info->os2_bmp) SkipBytes(buffer, 1); // unused
}
}
return buffer->real_pos <= info->offset;
}
/*
* Reads the bitmap
* 1 bpp and 4 bpp bitmaps are converted to 8 bpp bitmaps
*/
bool BmpReadBitmap(BmpBuffer *buffer, BmpInfo *info, BmpData *data)
{
assert(info != NULL && data != NULL);
data->bitmap = (byte*)calloc(info->width * info->height, ((info->bpp == 24) ? 3 : 1) * sizeof(byte));
if (data->bitmap == NULL) return false;
/* Load image */
SetStreamOffset(buffer, info->offset);
switch (info->compression) {
case 0: // no compression
switch (info->bpp) {
case 1: return BmpRead1(buffer, info, data);
case 4: return BmpRead4(buffer, info, data);
case 8: return BmpRead8(buffer, info, data);
case 24: return BmpRead24(buffer, info, data);
default: NOT_REACHED(); return false;
}
case 1: return BmpRead8Rle(buffer, info, data); // 8-bit RLE compression
case 2: return BmpRead4Rle(buffer, info, data); // 4-bit RLE compression
default: NOT_REACHED(); return false;
}
}
void BmpDestroyData(BmpData *data)
{
assert(data != NULL);
free(data->palette);
free(data->bitmap);
}