/
IMG_bmp.c
892 lines (819 loc) · 25.4 KB
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/*
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SDL_image: An example image loading library for use with SDL
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Copyright (C) 1997-2013 Sam Lantinga <slouken@libsdl.org>
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This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
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1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
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*/
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#if (!defined(__APPLE__) || defined(SDL_IMAGE_USE_COMMON_BACKEND)) || !defined(BMP_USES_IMAGEIO)
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/* This is a BMP image file loading framework
*
* ICO/CUR file support is here as well since it uses similar internal
* representation
*
* A good test suite of BMP images is available at:
* http://entropymine.com/jason/bmpsuite/bmpsuite/html/bmpsuite.html
*/
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#include <stdio.h>
#include <string.h>
#include "SDL_image.h"
#ifdef LOAD_BMP
/* See if an image is contained in a data source */
int IMG_isBMP(SDL_RWops *src)
{
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Sint64 start;
int is_BMP;
char magic[2];
if ( !src )
return 0;
start = SDL_RWtell(src);
is_BMP = 0;
if ( SDL_RWread(src, magic, sizeof(magic), 1) ) {
if ( SDL_strncmp(magic, "BM", 2) == 0 ) {
is_BMP = 1;
}
}
SDL_RWseek(src, start, RW_SEEK_SET);
return(is_BMP);
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}
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static int IMG_isICOCUR(SDL_RWops *src, int type)
{
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Sint64 start;
int is_ICOCUR;
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/* The Win32 ICO file header (14 bytes) */
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Uint16 bfReserved;
Uint16 bfType;
Uint16 bfCount;
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if ( !src )
return 0;
start = SDL_RWtell(src);
is_ICOCUR = 0;
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bfReserved = SDL_ReadLE16(src);
bfType = SDL_ReadLE16(src);
bfCount = SDL_ReadLE16(src);
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if ((bfReserved == 0) && (bfType == type) && (bfCount != 0))
is_ICOCUR = 1;
SDL_RWseek(src, start, RW_SEEK_SET);
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return (is_ICOCUR);
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}
int IMG_isICO(SDL_RWops *src)
{
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return IMG_isICOCUR(src, 1);
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}
int IMG_isCUR(SDL_RWops *src)
{
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return IMG_isICOCUR(src, 2);
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}
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#include "SDL_error.h"
#include "SDL_video.h"
#include "SDL_endian.h"
/* Compression encodings for BMP files */
#ifndef BI_RGB
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#define BI_RGB 0
#define BI_RLE8 1
#define BI_RLE4 2
#define BI_BITFIELDS 3
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#endif
static int readRlePixels(SDL_Surface * surface, SDL_RWops * src, int isRle8)
{
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/*
| Sets the surface pixels from src. A bmp image is upside down.
*/
int pitch = surface->pitch;
int height = surface->h;
Uint8 *start = (Uint8 *)surface->pixels;
Uint8 *end = start + (height*pitch);
Uint8 *bits = end-pitch, *spot;
int ofs = 0;
Uint8 ch;
Uint8 needsPad;
#define COPY_PIXEL(x) spot = &bits[ofs++]; if(spot >= start && spot < end) *spot = (x)
for (;;) {
if ( !SDL_RWread(src, &ch, 1, 1) ) return 1;
/*
| encoded mode starts with a run length, and then a byte
| with two colour indexes to alternate between for the run
*/
if ( ch ) {
Uint8 pixel;
if ( !SDL_RWread(src, &pixel, 1, 1) ) return 1;
if ( isRle8 ) { /* 256-color bitmap, compressed */
do {
COPY_PIXEL(pixel);
} while (--ch);
} else { /* 16-color bitmap, compressed */
Uint8 pixel0 = pixel >> 4;
Uint8 pixel1 = pixel & 0x0F;
for (;;) {
COPY_PIXEL(pixel0); /* even count, high nibble */
if (!--ch) break;
COPY_PIXEL(pixel1); /* odd count, low nibble */
if (!--ch) break;
}
}
} else {
/*
| A leading zero is an escape; it may signal the end of the bitmap,
| a cursor move, or some absolute data.
| zero tag may be absolute mode or an escape
*/
if ( !SDL_RWread(src, &ch, 1, 1) ) return 1;
switch (ch) {
case 0: /* end of line */
ofs = 0;
bits -= pitch; /* go to previous */
break;
case 1: /* end of bitmap */
return 0; /* success! */
case 2: /* delta */
if ( !SDL_RWread(src, &ch, 1, 1) ) return 1;
ofs += ch;
if ( !SDL_RWread(src, &ch, 1, 1) ) return 1;
bits -= (ch * pitch);
break;
default: /* no compression */
if (isRle8) {
needsPad = ( ch & 1 );
do {
Uint8 pixel;
if ( !SDL_RWread(src, &pixel, 1, 1) ) return 1;
COPY_PIXEL(pixel);
} while (--ch);
} else {
needsPad = ( ((ch+1)>>1) & 1 ); /* (ch+1)>>1: bytes size */
for (;;) {
Uint8 pixel;
if ( !SDL_RWread(src, &pixel, 1, 1) ) return 1;
COPY_PIXEL(pixel >> 4);
if (!--ch) break;
COPY_PIXEL(pixel & 0x0F);
if (!--ch) break;
}
}
/* pad at even boundary */
if ( needsPad && !SDL_RWread(src, &ch, 1, 1) ) return 1;
break;
}
}
}
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}
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static void CorrectAlphaChannel(SDL_Surface *surface)
{
/* Check to see if there is any alpha channel data */
SDL_bool hasAlpha = SDL_FALSE;
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
int alphaChannelOffset = 0;
#else
int alphaChannelOffset = 3;
#endif
Uint8 *alpha = ((Uint8*)surface->pixels) + alphaChannelOffset;
Uint8 *end = alpha + surface->h * surface->pitch;
while (alpha < end) {
if (*alpha != 0) {
hasAlpha = SDL_TRUE;
break;
}
alpha += 4;
}
if (!hasAlpha) {
alpha = ((Uint8*)surface->pixels) + alphaChannelOffset;
while (alpha < end) {
*alpha = SDL_ALPHA_OPAQUE;
alpha += 4;
}
}
}
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static SDL_Surface *LoadBMP_RW (SDL_RWops *src, int freesrc)
{
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SDL_bool was_error;
Sint64 fp_offset;
int bmpPitch;
int i, pad;
SDL_Surface *surface;
Uint32 Rmask;
Uint32 Gmask;
Uint32 Bmask;
Uint32 Amask;
SDL_Palette *palette;
Uint8 *bits;
Uint8 *top, *end;
SDL_bool topDown;
int ExpandBMP;
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SDL_bool correctAlpha = SDL_FALSE;
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/* The Win32 BMP file header (14 bytes) */
char magic[2];
Uint32 bfSize;
Uint16 bfReserved1;
Uint16 bfReserved2;
Uint32 bfOffBits;
/* The Win32 BITMAPINFOHEADER struct (40 bytes) */
Uint32 biSize;
Sint32 biWidth;
Sint32 biHeight;
Uint16 biPlanes;
Uint16 biBitCount;
Uint32 biCompression;
Uint32 biSizeImage;
Sint32 biXPelsPerMeter;
Sint32 biYPelsPerMeter;
Uint32 biClrUsed;
Uint32 biClrImportant;
/* Make sure we are passed a valid data source */
surface = NULL;
was_error = SDL_FALSE;
if ( src == NULL ) {
was_error = SDL_TRUE;
goto done;
}
/* Read in the BMP file header */
fp_offset = SDL_RWtell(src);
SDL_ClearError();
if ( SDL_RWread(src, magic, 1, 2) != 2 ) {
SDL_Error(SDL_EFREAD);
was_error = SDL_TRUE;
goto done;
}
if ( SDL_strncmp(magic, "BM", 2) != 0 ) {
IMG_SetError("File is not a Windows BMP file");
was_error = SDL_TRUE;
goto done;
}
bfSize = SDL_ReadLE32(src);
bfReserved1 = SDL_ReadLE16(src);
bfReserved2 = SDL_ReadLE16(src);
bfOffBits = SDL_ReadLE32(src);
/* Read the Win32 BITMAPINFOHEADER */
biSize = SDL_ReadLE32(src);
if ( biSize == 12 ) {
biWidth = (Uint32)SDL_ReadLE16(src);
biHeight = (Uint32)SDL_ReadLE16(src);
biPlanes = SDL_ReadLE16(src);
biBitCount = SDL_ReadLE16(src);
biCompression = BI_RGB;
biSizeImage = 0;
biXPelsPerMeter = 0;
biYPelsPerMeter = 0;
biClrUsed = 0;
biClrImportant = 0;
} else {
biWidth = SDL_ReadLE32(src);
biHeight = SDL_ReadLE32(src);
biPlanes = SDL_ReadLE16(src);
biBitCount = SDL_ReadLE16(src);
biCompression = SDL_ReadLE32(src);
biSizeImage = SDL_ReadLE32(src);
biXPelsPerMeter = SDL_ReadLE32(src);
biYPelsPerMeter = SDL_ReadLE32(src);
biClrUsed = SDL_ReadLE32(src);
biClrImportant = SDL_ReadLE32(src);
}
if (biHeight < 0) {
topDown = SDL_TRUE;
biHeight = -biHeight;
} else {
topDown = SDL_FALSE;
}
/* Check for read error */
if ( strcmp(SDL_GetError(), "") != 0 ) {
was_error = SDL_TRUE;
goto done;
}
/* Expand 1 and 4 bit bitmaps to 8 bits per pixel */
switch (biBitCount) {
case 1:
case 4:
ExpandBMP = biBitCount;
biBitCount = 8;
break;
default:
ExpandBMP = 0;
break;
}
/* RLE4 and RLE8 BMP compression is supported */
Rmask = Gmask = Bmask = Amask = 0;
switch (biCompression) {
case BI_RGB:
/* If there are no masks, use the defaults */
if ( bfOffBits == (14+biSize) ) {
/* Default values for the BMP format */
switch (biBitCount) {
case 15:
case 16:
Rmask = 0x7C00;
Gmask = 0x03E0;
Bmask = 0x001F;
break;
case 24:
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#if SDL_BYTEORDER == SDL_BIG_ENDIAN
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Rmask = 0x000000FF;
Gmask = 0x0000FF00;
Bmask = 0x00FF0000;
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#else
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Rmask = 0x00FF0000;
Gmask = 0x0000FF00;
Bmask = 0x000000FF;
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#endif
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break;
case 32:
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/* We don't know if this has alpha channel or not */
correctAlpha = SDL_TRUE;
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Amask = 0xFF000000;
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Rmask = 0x00FF0000;
Gmask = 0x0000FF00;
Bmask = 0x000000FF;
break;
default:
break;
}
break;
}
/* Fall through -- read the RGB masks */
default:
switch (biBitCount) {
case 15:
case 16:
Rmask = SDL_ReadLE32(src);
Gmask = SDL_ReadLE32(src);
Bmask = SDL_ReadLE32(src);
break;
case 32:
Rmask = SDL_ReadLE32(src);
Gmask = SDL_ReadLE32(src);
Bmask = SDL_ReadLE32(src);
Amask = SDL_ReadLE32(src);
break;
default:
break;
}
break;
}
/* Create a compatible surface, note that the colors are RGB ordered */
surface = SDL_CreateRGBSurface(SDL_SWSURFACE,
biWidth, biHeight, biBitCount, Rmask, Gmask, Bmask, Amask);
if ( surface == NULL ) {
was_error = SDL_TRUE;
goto done;
}
/* Load the palette, if any */
palette = (surface->format)->palette;
if ( palette ) {
if ( SDL_RWseek(src, fp_offset+14+biSize, RW_SEEK_SET) < 0 ) {
SDL_Error(SDL_EFSEEK);
was_error = SDL_TRUE;
goto done;
}
/*
| guich: always use 1<<bpp b/c some bitmaps can bring wrong information
| for colorsUsed
*/
/* if ( biClrUsed == 0 ) { */
biClrUsed = 1 << biBitCount;
/* } */
if ( biSize == 12 ) {
for ( i = 0; i < (int)biClrUsed; ++i ) {
SDL_RWread(src, &palette->colors[i].b, 1, 1);
SDL_RWread(src, &palette->colors[i].g, 1, 1);
SDL_RWread(src, &palette->colors[i].r, 1, 1);
palette->colors[i].a = SDL_ALPHA_OPAQUE;
}
} else {
for ( i = 0; i < (int)biClrUsed; ++i ) {
SDL_RWread(src, &palette->colors[i].b, 1, 1);
SDL_RWread(src, &palette->colors[i].g, 1, 1);
SDL_RWread(src, &palette->colors[i].r, 1, 1);
SDL_RWread(src, &palette->colors[i].a, 1, 1);
/* According to Microsoft documentation, the fourth element
is reserved and must be zero, so we shouldn't treat it as
alpha.
*/
palette->colors[i].a = SDL_ALPHA_OPAQUE;
}
}
palette->ncolors = biClrUsed;
}
/* Read the surface pixels. Note that the bmp image is upside down */
if ( SDL_RWseek(src, fp_offset+bfOffBits, RW_SEEK_SET) < 0 ) {
SDL_Error(SDL_EFSEEK);
was_error = SDL_TRUE;
goto done;
}
if ((biCompression == BI_RLE4) || (biCompression == BI_RLE8)) {
was_error = (SDL_bool)readRlePixels(surface, src, biCompression == BI_RLE8);
if (was_error) IMG_SetError("Error reading from BMP");
goto done;
}
top = (Uint8 *)surface->pixels;
end = (Uint8 *)surface->pixels+(surface->h*surface->pitch);
switch (ExpandBMP) {
case 1:
bmpPitch = (biWidth + 7) >> 3;
pad = (((bmpPitch)%4) ? (4-((bmpPitch)%4)) : 0);
break;
case 4:
bmpPitch = (biWidth + 1) >> 1;
pad = (((bmpPitch)%4) ? (4-((bmpPitch)%4)) : 0);
break;
default:
pad = ((surface->pitch%4) ?
(4-(surface->pitch%4)) : 0);
break;
}
if ( topDown ) {
bits = top;
} else {
bits = end - surface->pitch;
}
while ( bits >= top && bits < end ) {
switch (ExpandBMP) {
case 1:
case 4: {
Uint8 pixel = 0;
int shift = (8-ExpandBMP);
for ( i=0; i<surface->w; ++i ) {
if ( i%(8/ExpandBMP) == 0 ) {
if ( !SDL_RWread(src, &pixel, 1, 1) ) {
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IMG_SetError("Error reading from BMP");
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was_error = SDL_TRUE;
goto done;
}
}
*(bits+i) = (pixel>>shift);
pixel <<= ExpandBMP;
} }
break;
default:
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if ( SDL_RWread(src, bits, 1, surface->pitch) != surface->pitch ) {
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SDL_Error(SDL_EFREAD);
was_error = SDL_TRUE;
goto done;
}
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#if SDL_BYTEORDER == SDL_BIG_ENDIAN
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/* Byte-swap the pixels if needed. Note that the 24bpp
case has already been taken care of above. */
switch(biBitCount) {
case 15:
case 16: {
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Uint16 *pix = (Uint16 *)bits;
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for(i = 0; i < surface->w; i++)
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pix[i] = SDL_Swap16(pix[i]);
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break;
}
case 32: {
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Uint32 *pix = (Uint32 *)bits;
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for(i = 0; i < surface->w; i++)
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pix[i] = SDL_Swap32(pix[i]);
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break;
}
}
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#endif
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break;
}
/* Skip padding bytes, ugh */
if ( pad ) {
Uint8 padbyte;
for ( i=0; i<pad; ++i ) {
SDL_RWread(src, &padbyte, 1, 1);
}
}
if ( topDown ) {
bits += surface->pitch;
} else {
bits -= surface->pitch;
}
}
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if (correctAlpha) {
CorrectAlphaChannel(surface);
}
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done:
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if ( was_error ) {
if ( src ) {
SDL_RWseek(src, fp_offset, RW_SEEK_SET);
}
if ( surface ) {
SDL_FreeSurface(surface);
}
surface = NULL;
}
if ( freesrc && src ) {
SDL_RWclose(src);
}
return(surface);
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}
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static Uint8
SDL_Read8(SDL_RWops * src)
{
Uint8 value;
SDL_RWread(src, &value, 1, 1);
return (value);
}
static SDL_Surface *
LoadICOCUR_RW(SDL_RWops * src, int type, int freesrc)
{
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SDL_bool was_error;
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Sint64 fp_offset;
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int bmpPitch;
int i, pad;
SDL_Surface *surface;
Uint32 Rmask;
Uint32 Gmask;
Uint32 Bmask;
Uint8 *bits;
int ExpandBMP;
int maxCol = 0;
int icoOfs = 0;
Uint32 palette[256];
/* The Win32 ICO file header (14 bytes) */
Uint16 bfReserved;
Uint16 bfType;
Uint16 bfCount;
/* The Win32 BITMAPINFOHEADER struct (40 bytes) */
Uint32 biSize;
Sint32 biWidth;
Sint32 biHeight;
Uint16 biPlanes;
Uint16 biBitCount;
Uint32 biCompression;
Uint32 biSizeImage;
Sint32 biXPelsPerMeter;
Sint32 biYPelsPerMeter;
Uint32 biClrUsed;
Uint32 biClrImportant;
/* Make sure we are passed a valid data source */
surface = NULL;
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was_error = SDL_FALSE;
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if (src == NULL) {
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was_error = SDL_TRUE;
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goto done;
}
/* Read in the ICO file header */
fp_offset = SDL_RWtell(src);
SDL_ClearError();
bfReserved = SDL_ReadLE16(src);
bfType = SDL_ReadLE16(src);
bfCount = SDL_ReadLE16(src);
if ((bfReserved != 0) || (bfType != type) || (bfCount == 0)) {
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IMG_SetError("File is not a Windows %s file", type == 1 ? "ICO" : "CUR");
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was_error = SDL_TRUE;
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goto done;
}
/* Read the Win32 Icon Directory */
for (i = 0; i < bfCount; i++) {
/* Icon Directory Entries */
int bWidth = SDL_Read8(src); /* Uint8, but 0 = 256 ! */
int bHeight = SDL_Read8(src); /* Uint8, but 0 = 256 ! */
int bColorCount = SDL_Read8(src); /* Uint8, but 0 = 256 ! */
Uint8 bReserved = SDL_Read8(src);
Uint16 wPlanes = SDL_ReadLE16(src);
Uint16 wBitCount = SDL_ReadLE16(src);
Uint32 dwBytesInRes = SDL_ReadLE32(src);
Uint32 dwImageOffset = SDL_ReadLE32(src);
if (!bWidth)
bWidth = 256;
if (!bHeight)
bHeight = 256;
if (!bColorCount)
bColorCount = 256;
//printf("%dx%d@%d - %08x\n", bWidth, bHeight, bColorCount, dwImageOffset);
if (bColorCount > maxCol) {
maxCol = bColorCount;
icoOfs = dwImageOffset;
//printf("marked\n");
}
}
/* Advance to the DIB Data */
if (SDL_RWseek(src, icoOfs, RW_SEEK_SET) < 0) {
SDL_Error(SDL_EFSEEK);
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was_error = SDL_TRUE;
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goto done;
}
/* Read the Win32 BITMAPINFOHEADER */
biSize = SDL_ReadLE32(src);
if (biSize == 40) {
biWidth = SDL_ReadLE32(src);
biHeight = SDL_ReadLE32(src);
biPlanes = SDL_ReadLE16(src);
biBitCount = SDL_ReadLE16(src);
biCompression = SDL_ReadLE32(src);
biSizeImage = SDL_ReadLE32(src);
biXPelsPerMeter = SDL_ReadLE32(src);
biYPelsPerMeter = SDL_ReadLE32(src);
biClrUsed = SDL_ReadLE32(src);
biClrImportant = SDL_ReadLE32(src);
} else {
667
IMG_SetError("Unsupported ICO bitmap format");
668
was_error = SDL_TRUE;
669
670
671
672
673
goto done;
}
/* Check for read error */
if (SDL_strcmp(SDL_GetError(), "") != 0) {
674
was_error = SDL_TRUE;
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
goto done;
}
/* We don't support any BMP compression right now */
switch (biCompression) {
case BI_RGB:
/* Default values for the BMP format */
switch (biBitCount) {
case 1:
case 4:
ExpandBMP = biBitCount;
biBitCount = 8;
break;
case 8:
ExpandBMP = 8;
break;
case 32:
Rmask = 0x00FF0000;
Gmask = 0x0000FF00;
Bmask = 0x000000FF;
ExpandBMP = 0;
break;
default:
698
IMG_SetError("ICO file with unsupported bit count");
699
was_error = SDL_TRUE;
700
701
702
703
goto done;
}
break;
default:
704
IMG_SetError("Compressed ICO files not supported");
705
was_error = SDL_TRUE;
706
707
708
709
710
711
712
713
714
715
goto done;
}
/* Create a RGBA surface */
biHeight = biHeight >> 1;
//printf("%d x %d\n", biWidth, biHeight);
surface =
SDL_CreateRGBSurface(0, biWidth, biHeight, 32, 0x00FF0000,
0x0000FF00, 0x000000FF, 0xFF000000);
if (surface == NULL) {
716
was_error = SDL_TRUE;
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
goto done;
}
/* Load the palette, if any */
//printf("bc %d bused %d\n", biBitCount, biClrUsed);
if (biBitCount <= 8) {
if (biClrUsed == 0) {
biClrUsed = 1 << biBitCount;
}
for (i = 0; i < (int) biClrUsed; ++i) {
SDL_RWread(src, &palette[i], 4, 1);
}
}
/* Read the surface pixels. Note that the bmp image is upside down */
bits = (Uint8 *) surface->pixels + (surface->h * surface->pitch);
switch (ExpandBMP) {
case 1:
bmpPitch = (biWidth + 7) >> 3;
pad = (((bmpPitch) % 4) ? (4 - ((bmpPitch) % 4)) : 0);
break;
case 4:
bmpPitch = (biWidth + 1) >> 1;
pad = (((bmpPitch) % 4) ? (4 - ((bmpPitch) % 4)) : 0);
break;
case 8:
bmpPitch = biWidth;
pad = (((bmpPitch) % 4) ? (4 - ((bmpPitch) % 4)) : 0);
break;
default:
bmpPitch = biWidth * 4;
pad = 0;
break;
}
while (bits > (Uint8 *) surface->pixels) {
bits -= surface->pitch;
switch (ExpandBMP) {
case 1:
case 4:
case 8:
{
Uint8 pixel = 0;
int shift = (8 - ExpandBMP);
for (i = 0; i < surface->w; ++i) {
if (i % (8 / ExpandBMP) == 0) {
if (!SDL_RWread(src, &pixel, 1, 1)) {
763
IMG_SetError("Error reading from ICO");
764
was_error = SDL_TRUE;
765
766
767
768
769
770
771
772
773
774
775
776
777
goto done;
}
}
*((Uint32 *) bits + i) = (palette[pixel >> shift]);
pixel <<= ExpandBMP;
}
}
break;
default:
if (SDL_RWread(src, bits, 1, surface->pitch)
!= surface->pitch) {
SDL_Error(SDL_EFREAD);
778
was_error = SDL_TRUE;
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
goto done;
}
break;
}
/* Skip padding bytes, ugh */
if (pad) {
Uint8 padbyte;
for (i = 0; i < pad; ++i) {
SDL_RWread(src, &padbyte, 1, 1);
}
}
}
/* Read the mask pixels. Note that the bmp image is upside down */
bits = (Uint8 *) surface->pixels + (surface->h * surface->pitch);
ExpandBMP = 1;
bmpPitch = (biWidth + 7) >> 3;
pad = (((bmpPitch) % 4) ? (4 - ((bmpPitch) % 4)) : 0);
while (bits > (Uint8 *) surface->pixels) {
Uint8 pixel = 0;
int shift = (8 - ExpandBMP);
bits -= surface->pitch;
for (i = 0; i < surface->w; ++i) {
if (i % (8 / ExpandBMP) == 0) {
if (!SDL_RWread(src, &pixel, 1, 1)) {
804
IMG_SetError("Error reading from ICO");
805
was_error = SDL_TRUE;
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
goto done;
}
}
*((Uint32 *) bits + i) |= ((pixel >> shift) ? 0 : 0xFF000000);
pixel <<= ExpandBMP;
}
/* Skip padding bytes, ugh */
if (pad) {
Uint8 padbyte;
for (i = 0; i < pad; ++i) {
SDL_RWread(src, &padbyte, 1, 1);
}
}
}
done:
if (was_error) {
if (src) {
SDL_RWseek(src, fp_offset, RW_SEEK_SET);
}
if (surface) {
SDL_FreeSurface(surface);
}
surface = NULL;
}
if (freesrc && src) {
SDL_RWclose(src);
}
return (surface);
}
836
837
838
/* Load a BMP type image from an SDL datasource */
SDL_Surface *IMG_LoadBMP_RW(SDL_RWops *src)
{
839
return(LoadBMP_RW(src, 0));
840
841
}
842
843
844
/* Load a ICO type image from an SDL datasource */
SDL_Surface *IMG_LoadICO_RW(SDL_RWops *src)
{
845
return(LoadICOCUR_RW(src, 1, 0));
846
847
848
849
850
}
/* Load a CUR type image from an SDL datasource */
SDL_Surface *IMG_LoadCUR_RW(SDL_RWops *src)
{
851
return(LoadICOCUR_RW(src, 2, 0));
852
853
}
854
855
856
857
858
#else
/* See if an image is contained in a data source */
int IMG_isBMP(SDL_RWops *src)
{
859
return(0);
860
861
}
862
863
int IMG_isICO(SDL_RWops *src)
{
864
return(0);
865
866
867
868
}
int IMG_isCUR(SDL_RWops *src)
{
869
return(0);
870
871
}
872
873
874
/* Load a BMP type image from an SDL datasource */
SDL_Surface *IMG_LoadBMP_RW(SDL_RWops *src)
{
875
return(NULL);
876
877
}
878
879
880
/* Load a BMP type image from an SDL datasource */
SDL_Surface *IMG_LoadCUR_RW(SDL_RWops *src)
{
881
return(NULL);
882
883
884
885
886
}
/* Load a BMP type image from an SDL datasource */
SDL_Surface *IMG_LoadICO_RW(SDL_RWops *src)
{
887
return(NULL);
888
889
}
890
#endif /* LOAD_BMP */
891
892
#endif /* !defined(__APPLE__) || defined(SDL_IMAGE_USE_COMMON_BACKEND) */