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https://github.com/thunderbrewhq/thunderbrew
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880 lines
27 KiB
C
880 lines
27 KiB
C
/*
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Simple DirectMedia Layer
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Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
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This software is provided 'as-is', without any express or implied
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warranty. In no event will the authors be held liable for any damages
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arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
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including commercial applications, and to alter it and redistribute it
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freely, subject to the following restrictions:
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1. The origin of this software must not be misrepresented; you must not
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claim that you wrote the original software. If you use this software
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in a product, an acknowledgment in the product documentation would be
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appreciated but is not required.
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2. Altered source versions must be plainly marked as such, and must not be
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misrepresented as being the original software.
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3. This notice may not be removed or altered from any source distribution.
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*/
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#include "SDL_internal.h"
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/*
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Code to load and save surfaces in Windows BMP format.
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Why support BMP format? Well, it's a native format for Windows, and
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most image processing programs can read and write it. It would be nice
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to be able to have at least one image format that we can natively load
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and save, and since PNG is so complex that it would bloat the library,
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BMP is a good alternative.
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This code currently supports Win32 DIBs in uncompressed 8 and 24 bpp.
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*/
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#include "SDL_pixels_c.h"
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#include "SDL_surface_c.h"
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#define SAVE_32BIT_BMP
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// Compression encodings for BMP files
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#ifndef BI_RGB
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#define BI_RGB 0
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#define BI_RLE8 1
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#define BI_RLE4 2
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#define BI_BITFIELDS 3
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#endif
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// Logical color space values for BMP files
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// https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-wmf/eb4bbd50-b3ce-4917-895c-be31f214797f
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#ifndef LCS_WINDOWS_COLOR_SPACE
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// 0x57696E20 == "Win "
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#define LCS_WINDOWS_COLOR_SPACE 0x57696E20
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#endif
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#ifndef LCS_sRGB
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// 0x73524742 == "sRGB"
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#define LCS_sRGB 0x73524742
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#endif
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// Logical/physical color relationship
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// https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-wmf/9fec0834-607d-427d-abd5-ab240fb0db38
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#ifndef LCS_GM_GRAPHICS
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#define LCS_GM_GRAPHICS 0x00000002
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#endif
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static bool readRlePixels(SDL_Surface *surface, SDL_IOStream *src, int isRle8)
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{
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/*
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| Sets the surface pixels from src. A bmp image is upside down.
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*/
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int pitch = surface->pitch;
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int height = surface->h;
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Uint8 *start = (Uint8 *)surface->pixels;
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Uint8 *end = start + (height * pitch);
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Uint8 *bits = end - pitch, *spot;
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int ofs = 0;
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Uint8 ch;
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Uint8 needsPad;
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const int pixels_per_byte = (isRle8 ? 1 : 2);
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#define COPY_PIXEL(x) \
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spot = &bits[ofs++]; \
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if (spot >= start && spot < end) \
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*spot = (x)
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for (;;) {
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if (!SDL_ReadU8(src, &ch)) {
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return false;
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}
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/*
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| encoded mode starts with a run length, and then a byte
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| with two colour indexes to alternate between for the run
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*/
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if (ch) {
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Uint8 pixel;
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if (!SDL_ReadU8(src, &pixel)) {
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return false;
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}
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ch /= pixels_per_byte;
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do {
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COPY_PIXEL(pixel);
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} while (--ch);
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} else {
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/*
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| A leading zero is an escape; it may signal the end of the bitmap,
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| a cursor move, or some absolute data.
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| zero tag may be absolute mode or an escape
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*/
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if (!SDL_ReadU8(src, &ch)) {
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return false;
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}
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switch (ch) {
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case 0: // end of line
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ofs = 0;
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bits -= pitch; // go to previous
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break;
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case 1: // end of bitmap
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return true; // success!
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case 2: // delta
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if (!SDL_ReadU8(src, &ch)) {
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return false;
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}
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ofs += ch / pixels_per_byte;
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if (!SDL_ReadU8(src, &ch)) {
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return false;
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}
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bits -= ((ch / pixels_per_byte) * pitch);
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break;
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default: // no compression
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ch /= pixels_per_byte;
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needsPad = (ch & 1);
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do {
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Uint8 pixel;
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if (!SDL_ReadU8(src, &pixel)) {
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return false;
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}
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COPY_PIXEL(pixel);
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} while (--ch);
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// pad at even boundary
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if (needsPad && !SDL_ReadU8(src, &ch)) {
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return false;
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}
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break;
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}
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}
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}
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}
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static void CorrectAlphaChannel(SDL_Surface *surface)
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{
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// Check to see if there is any alpha channel data
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bool hasAlpha = false;
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#if SDL_BYTEORDER == SDL_BIG_ENDIAN
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int alphaChannelOffset = 0;
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#else
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int alphaChannelOffset = 3;
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#endif
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Uint8 *alpha = ((Uint8 *)surface->pixels) + alphaChannelOffset;
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Uint8 *end = alpha + surface->h * surface->pitch;
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while (alpha < end) {
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if (*alpha != 0) {
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hasAlpha = true;
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break;
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}
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alpha += 4;
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}
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if (!hasAlpha) {
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alpha = ((Uint8 *)surface->pixels) + alphaChannelOffset;
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while (alpha < end) {
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*alpha = SDL_ALPHA_OPAQUE;
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alpha += 4;
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}
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}
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}
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SDL_Surface *SDL_LoadBMP_IO(SDL_IOStream *src, bool closeio)
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{
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bool was_error = true;
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Sint64 fp_offset = 0;
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int i, pad;
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SDL_Surface *surface;
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Uint32 Rmask = 0;
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Uint32 Gmask = 0;
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Uint32 Bmask = 0;
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Uint32 Amask = 0;
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Uint8 *bits;
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Uint8 *top, *end;
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bool topDown;
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bool haveRGBMasks = false;
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bool haveAlphaMask = false;
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bool correctAlpha = false;
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// The Win32 BMP file header (14 bytes)
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char magic[2];
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// Uint32 bfSize;
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// Uint16 bfReserved1;
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// Uint16 bfReserved2;
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Uint32 bfOffBits;
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// The Win32 BITMAPINFOHEADER struct (40 bytes)
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Uint32 biSize;
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Sint32 biWidth = 0;
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Sint32 biHeight = 0;
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// Uint16 biPlanes;
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Uint16 biBitCount = 0;
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Uint32 biCompression = 0;
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// Uint32 biSizeImage;
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// Sint32 biXPelsPerMeter;
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// Sint32 biYPelsPerMeter;
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Uint32 biClrUsed = 0;
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// Uint32 biClrImportant;
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// Make sure we are passed a valid data source
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surface = NULL;
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if (!src) {
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SDL_InvalidParamError("src");
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goto done;
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}
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// Read in the BMP file header
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fp_offset = SDL_TellIO(src);
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if (fp_offset < 0) {
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goto done;
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}
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SDL_ClearError();
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if (SDL_ReadIO(src, magic, 2) != 2) {
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goto done;
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}
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if (SDL_strncmp(magic, "BM", 2) != 0) {
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SDL_SetError("File is not a Windows BMP file");
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goto done;
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}
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if (!SDL_ReadU32LE(src, NULL /* bfSize */) ||
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!SDL_ReadU16LE(src, NULL /* bfReserved1 */) ||
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!SDL_ReadU16LE(src, NULL /* bfReserved2 */) ||
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!SDL_ReadU32LE(src, &bfOffBits)) {
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goto done;
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}
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// Read the Win32 BITMAPINFOHEADER
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if (!SDL_ReadU32LE(src, &biSize)) {
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goto done;
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}
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if (biSize == 12) { // really old BITMAPCOREHEADER
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Uint16 biWidth16, biHeight16;
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if (!SDL_ReadU16LE(src, &biWidth16) ||
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!SDL_ReadU16LE(src, &biHeight16) ||
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!SDL_ReadU16LE(src, NULL /* biPlanes */) ||
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!SDL_ReadU16LE(src, &biBitCount)) {
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goto done;
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}
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biWidth = biWidth16;
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biHeight = biHeight16;
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biCompression = BI_RGB;
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// biSizeImage = 0;
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// biXPelsPerMeter = 0;
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// biYPelsPerMeter = 0;
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biClrUsed = 0;
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// biClrImportant = 0;
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} else if (biSize >= 40) { // some version of BITMAPINFOHEADER
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Uint32 headerSize;
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if (!SDL_ReadS32LE(src, &biWidth) ||
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!SDL_ReadS32LE(src, &biHeight) ||
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!SDL_ReadU16LE(src, NULL /* biPlanes */) ||
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!SDL_ReadU16LE(src, &biBitCount) ||
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!SDL_ReadU32LE(src, &biCompression) ||
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!SDL_ReadU32LE(src, NULL /* biSizeImage */) ||
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!SDL_ReadU32LE(src, NULL /* biXPelsPerMeter */) ||
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!SDL_ReadU32LE(src, NULL /* biYPelsPerMeter */) ||
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!SDL_ReadU32LE(src, &biClrUsed) ||
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!SDL_ReadU32LE(src, NULL /* biClrImportant */)) {
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goto done;
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}
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// 64 == BITMAPCOREHEADER2, an incompatible OS/2 2.x extension. Skip this stuff for now.
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if (biSize != 64) {
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/* This is complicated. If compression is BI_BITFIELDS, then
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we have 3 DWORDS that specify the RGB masks. This is either
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stored here in an BITMAPV2INFOHEADER (which only differs in
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that it adds these RGB masks) and biSize >= 52, or we've got
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these masks stored in the exact same place, but strictly
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speaking, this is the bmiColors field in BITMAPINFO immediately
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following the legacy v1 info header, just past biSize. */
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if (biCompression == BI_BITFIELDS) {
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haveRGBMasks = true;
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if (!SDL_ReadU32LE(src, &Rmask) ||
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!SDL_ReadU32LE(src, &Gmask) ||
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!SDL_ReadU32LE(src, &Bmask)) {
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goto done;
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}
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// ...v3 adds an alpha mask.
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if (biSize >= 56) { // BITMAPV3INFOHEADER; adds alpha mask
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haveAlphaMask = true;
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if (!SDL_ReadU32LE(src, &Amask)) {
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goto done;
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}
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}
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} else {
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// the mask fields are ignored for v2+ headers if not BI_BITFIELD.
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if (biSize >= 52) { // BITMAPV2INFOHEADER; adds RGB masks
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if (!SDL_ReadU32LE(src, NULL /* Rmask */) ||
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!SDL_ReadU32LE(src, NULL /* Gmask */) ||
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!SDL_ReadU32LE(src, NULL /* Bmask */)) {
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goto done;
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}
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}
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if (biSize >= 56) { // BITMAPV3INFOHEADER; adds alpha mask
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if (!SDL_ReadU32LE(src, NULL /* Amask */)) {
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goto done;
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}
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}
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}
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/* Insert other fields here; Wikipedia and MSDN say we're up to
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v5 of this header, but we ignore those for now (they add gamma,
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color spaces, etc). Ignoring the weird OS/2 2.x format, we
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currently parse up to v3 correctly (hopefully!). */
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}
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// skip any header bytes we didn't handle...
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headerSize = (Uint32)(SDL_TellIO(src) - (fp_offset + 14));
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if (biSize > headerSize) {
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if (SDL_SeekIO(src, (biSize - headerSize), SDL_IO_SEEK_CUR) < 0) {
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goto done;
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}
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}
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}
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if (biWidth <= 0 || biHeight == 0) {
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SDL_SetError("BMP file with bad dimensions (%" SDL_PRIs32 "x%" SDL_PRIs32 ")", biWidth, biHeight);
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goto done;
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}
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if (biHeight < 0) {
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topDown = true;
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biHeight = -biHeight;
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} else {
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topDown = false;
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}
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// Check for read error
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if (SDL_strcmp(SDL_GetError(), "") != 0) {
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goto done;
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}
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// Reject invalid bit depths
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switch (biBitCount) {
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case 0:
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case 3:
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case 5:
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case 6:
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case 7:
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SDL_SetError("%u bpp BMP images are not supported", biBitCount);
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goto done;
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default:
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break;
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}
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// RLE4 and RLE8 BMP compression is supported
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switch (biCompression) {
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case BI_RGB:
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// If there are no masks, use the defaults
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SDL_assert(!haveRGBMasks);
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SDL_assert(!haveAlphaMask);
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// Default values for the BMP format
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switch (biBitCount) {
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case 15:
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case 16:
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// SDL_PIXELFORMAT_XRGB1555 or SDL_PIXELFORMAT_ARGB1555 if Amask
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Rmask = 0x7C00;
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Gmask = 0x03E0;
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Bmask = 0x001F;
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break;
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case 24:
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#if SDL_BYTEORDER == SDL_BIG_ENDIAN
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// SDL_PIXELFORMAT_RGB24
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Rmask = 0x000000FF;
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Gmask = 0x0000FF00;
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Bmask = 0x00FF0000;
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#else
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// SDL_PIXELFORMAT_BGR24
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Rmask = 0x00FF0000;
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Gmask = 0x0000FF00;
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Bmask = 0x000000FF;
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#endif
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break;
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case 32:
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// We don't know if this has alpha channel or not
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correctAlpha = true;
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// SDL_PIXELFORMAT_RGBA8888
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Amask = 0xFF000000;
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Rmask = 0x00FF0000;
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Gmask = 0x0000FF00;
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Bmask = 0x000000FF;
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break;
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default:
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break;
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}
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break;
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case BI_BITFIELDS:
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break; // we handled this in the info header.
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default:
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break;
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}
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// Create a compatible surface, note that the colors are RGB ordered
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{
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SDL_PixelFormat format;
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// Get the pixel format
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format = SDL_GetPixelFormatForMasks(biBitCount, Rmask, Gmask, Bmask, Amask);
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surface = SDL_CreateSurface(biWidth, biHeight, format);
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if (!surface) {
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goto done;
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}
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}
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// Load the palette, if any
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if (SDL_ISPIXELFORMAT_INDEXED(surface->format)) {
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SDL_Palette *palette = SDL_CreateSurfacePalette(surface);
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if (!palette) {
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goto done;
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}
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if (SDL_SeekIO(src, fp_offset + 14 + biSize, SDL_IO_SEEK_SET) < 0) {
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SDL_SetError("Error seeking in datastream");
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goto done;
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}
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if (biBitCount >= 32) { // we shift biClrUsed by this value later.
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SDL_SetError("Unsupported or incorrect biBitCount field");
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goto done;
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}
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if (biClrUsed == 0) {
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biClrUsed = 1 << biBitCount;
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}
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if (biClrUsed > (Uint32)palette->ncolors) {
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biClrUsed = 1 << biBitCount; // try forcing it?
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if (biClrUsed > (Uint32)palette->ncolors) {
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SDL_SetError("Unsupported or incorrect biClrUsed field");
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goto done;
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}
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}
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palette->ncolors = biClrUsed;
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if (biSize == 12) {
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for (i = 0; i < palette->ncolors; ++i) {
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if (!SDL_ReadU8(src, &palette->colors[i].b) ||
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!SDL_ReadU8(src, &palette->colors[i].g) ||
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!SDL_ReadU8(src, &palette->colors[i].r)) {
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goto done;
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}
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palette->colors[i].a = SDL_ALPHA_OPAQUE;
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}
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} else {
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for (i = 0; i < palette->ncolors; ++i) {
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if (!SDL_ReadU8(src, &palette->colors[i].b) ||
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!SDL_ReadU8(src, &palette->colors[i].g) ||
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!SDL_ReadU8(src, &palette->colors[i].r) ||
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!SDL_ReadU8(src, &palette->colors[i].a)) {
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goto done;
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}
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/* According to Microsoft documentation, the fourth element
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is reserved and must be zero, so we shouldn't treat it as
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alpha.
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*/
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palette->colors[i].a = SDL_ALPHA_OPAQUE;
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}
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}
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}
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// Read the surface pixels. Note that the bmp image is upside down
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if (SDL_SeekIO(src, fp_offset + bfOffBits, SDL_IO_SEEK_SET) < 0) {
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SDL_SetError("Error seeking in datastream");
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goto done;
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}
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if ((biCompression == BI_RLE4) || (biCompression == BI_RLE8)) {
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if (!readRlePixels(surface, src, biCompression == BI_RLE8)) {
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SDL_SetError("Error reading from datastream");
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goto done;
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}
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// Success!
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was_error = false;
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goto done;
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}
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top = (Uint8 *)surface->pixels;
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end = (Uint8 *)surface->pixels + (surface->h * surface->pitch);
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pad = ((surface->pitch % 4) ? (4 - (surface->pitch % 4)) : 0);
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if (topDown) {
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bits = top;
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} else {
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bits = end - surface->pitch;
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}
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while (bits >= top && bits < end) {
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if (SDL_ReadIO(src, bits, surface->pitch) != (size_t)surface->pitch) {
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goto done;
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}
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if (biBitCount == 8 && surface->palette && biClrUsed < (1u << biBitCount)) {
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for (i = 0; i < surface->w; ++i) {
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if (bits[i] >= biClrUsed) {
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SDL_SetError("A BMP image contains a pixel with a color out of the palette");
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goto done;
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}
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|
}
|
|
}
|
|
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
|
|
/* Byte-swap the pixels if needed. Note that the 24bpp
|
|
case has already been taken care of above. */
|
|
switch (biBitCount) {
|
|
case 15:
|
|
case 16:
|
|
{
|
|
Uint16 *pix = (Uint16 *)bits;
|
|
for (i = 0; i < surface->w; i++) {
|
|
pix[i] = SDL_Swap16(pix[i]);
|
|
}
|
|
break;
|
|
}
|
|
|
|
case 32:
|
|
{
|
|
Uint32 *pix = (Uint32 *)bits;
|
|
for (i = 0; i < surface->w; i++) {
|
|
pix[i] = SDL_Swap32(pix[i]);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
// Skip padding bytes, ugh
|
|
if (pad) {
|
|
Uint8 padbyte;
|
|
for (i = 0; i < pad; ++i) {
|
|
if (!SDL_ReadU8(src, &padbyte)) {
|
|
goto done;
|
|
}
|
|
}
|
|
}
|
|
if (topDown) {
|
|
bits += surface->pitch;
|
|
} else {
|
|
bits -= surface->pitch;
|
|
}
|
|
}
|
|
if (correctAlpha) {
|
|
CorrectAlphaChannel(surface);
|
|
}
|
|
|
|
was_error = false;
|
|
|
|
done:
|
|
if (was_error) {
|
|
if (src) {
|
|
SDL_SeekIO(src, fp_offset, SDL_IO_SEEK_SET);
|
|
}
|
|
SDL_DestroySurface(surface);
|
|
surface = NULL;
|
|
}
|
|
if (closeio && src) {
|
|
SDL_CloseIO(src);
|
|
}
|
|
return surface;
|
|
}
|
|
|
|
SDL_Surface *SDL_LoadBMP(const char *file)
|
|
{
|
|
SDL_IOStream *stream = SDL_IOFromFile(file, "rb");
|
|
if (!stream) {
|
|
return NULL;
|
|
}
|
|
return SDL_LoadBMP_IO(stream, true);
|
|
}
|
|
|
|
bool SDL_SaveBMP_IO(SDL_Surface *surface, SDL_IOStream *dst, bool closeio)
|
|
{
|
|
bool was_error = true;
|
|
Sint64 fp_offset, new_offset;
|
|
int i, pad;
|
|
SDL_Surface *intermediate_surface = NULL;
|
|
Uint8 *bits;
|
|
bool save32bit = false;
|
|
bool saveLegacyBMP = false;
|
|
|
|
// The Win32 BMP file header (14 bytes)
|
|
char magic[2] = { 'B', 'M' };
|
|
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;
|
|
|
|
// The additional header members from the Win32 BITMAPV4HEADER struct (108 bytes in total)
|
|
Uint32 bV4RedMask = 0;
|
|
Uint32 bV4GreenMask = 0;
|
|
Uint32 bV4BlueMask = 0;
|
|
Uint32 bV4AlphaMask = 0;
|
|
Uint32 bV4CSType = 0;
|
|
Sint32 bV4Endpoints[3 * 3] = { 0 };
|
|
Uint32 bV4GammaRed = 0;
|
|
Uint32 bV4GammaGreen = 0;
|
|
Uint32 bV4GammaBlue = 0;
|
|
|
|
// The additional header members from the Win32 BITMAPV5HEADER struct (124 bytes in total)
|
|
Uint32 bV5Intent = 0;
|
|
Uint32 bV5ProfileData = 0;
|
|
Uint32 bV5ProfileSize = 0;
|
|
Uint32 bV5Reserved = 0;
|
|
|
|
// Make sure we have somewhere to save
|
|
if (!SDL_SurfaceValid(surface)) {
|
|
SDL_InvalidParamError("surface");
|
|
goto done;
|
|
}
|
|
if (!dst) {
|
|
SDL_InvalidParamError("dst");
|
|
goto done;
|
|
}
|
|
|
|
#ifdef SAVE_32BIT_BMP
|
|
// We can save alpha information in a 32-bit BMP
|
|
if (SDL_BITSPERPIXEL(surface->format) >= 8 &&
|
|
(SDL_ISPIXELFORMAT_ALPHA(surface->format) ||
|
|
surface->map.info.flags & SDL_COPY_COLORKEY)) {
|
|
save32bit = true;
|
|
}
|
|
#endif // SAVE_32BIT_BMP
|
|
|
|
if (surface->palette && !save32bit) {
|
|
if (SDL_BITSPERPIXEL(surface->format) == 8) {
|
|
intermediate_surface = surface;
|
|
} else {
|
|
SDL_SetError("%u bpp BMP files not supported",
|
|
SDL_BITSPERPIXEL(surface->format));
|
|
goto done;
|
|
}
|
|
} else if ((surface->format == SDL_PIXELFORMAT_BGR24 && !save32bit) ||
|
|
(surface->format == SDL_PIXELFORMAT_BGRA32 && save32bit)) {
|
|
intermediate_surface = surface;
|
|
} else {
|
|
SDL_PixelFormat pixel_format;
|
|
|
|
/* If the surface has a colorkey or alpha channel we'll save a
|
|
32-bit BMP with alpha channel, otherwise save a 24-bit BMP. */
|
|
if (save32bit) {
|
|
pixel_format = SDL_PIXELFORMAT_BGRA32;
|
|
} else {
|
|
pixel_format = SDL_PIXELFORMAT_BGR24;
|
|
}
|
|
intermediate_surface = SDL_ConvertSurface(surface, pixel_format);
|
|
if (!intermediate_surface) {
|
|
SDL_SetError("Couldn't convert image to %d bpp",
|
|
(int)SDL_BITSPERPIXEL(pixel_format));
|
|
goto done;
|
|
}
|
|
}
|
|
|
|
if (save32bit) {
|
|
saveLegacyBMP = SDL_GetHintBoolean(SDL_HINT_BMP_SAVE_LEGACY_FORMAT, false);
|
|
}
|
|
|
|
if (SDL_LockSurface(intermediate_surface)) {
|
|
const size_t bw = intermediate_surface->w * intermediate_surface->fmt->bytes_per_pixel;
|
|
|
|
// Set the BMP file header values
|
|
bfSize = 0; // We'll write this when we're done
|
|
bfReserved1 = 0;
|
|
bfReserved2 = 0;
|
|
bfOffBits = 0; // We'll write this when we're done
|
|
|
|
// Write the BMP file header values
|
|
fp_offset = SDL_TellIO(dst);
|
|
if (fp_offset < 0) {
|
|
goto done;
|
|
}
|
|
if (SDL_WriteIO(dst, magic, 2) != 2 ||
|
|
!SDL_WriteU32LE(dst, bfSize) ||
|
|
!SDL_WriteU16LE(dst, bfReserved1) ||
|
|
!SDL_WriteU16LE(dst, bfReserved2) ||
|
|
!SDL_WriteU32LE(dst, bfOffBits)) {
|
|
goto done;
|
|
}
|
|
|
|
// Set the BMP info values
|
|
biSize = 40;
|
|
biWidth = intermediate_surface->w;
|
|
biHeight = intermediate_surface->h;
|
|
biPlanes = 1;
|
|
biBitCount = intermediate_surface->fmt->bits_per_pixel;
|
|
biCompression = BI_RGB;
|
|
biSizeImage = intermediate_surface->h * intermediate_surface->pitch;
|
|
biXPelsPerMeter = 0;
|
|
biYPelsPerMeter = 0;
|
|
if (intermediate_surface->palette) {
|
|
biClrUsed = intermediate_surface->palette->ncolors;
|
|
} else {
|
|
biClrUsed = 0;
|
|
}
|
|
biClrImportant = 0;
|
|
|
|
// Set the BMP info values
|
|
if (save32bit && !saveLegacyBMP) {
|
|
biSize = 124;
|
|
// Version 4 values
|
|
biCompression = BI_BITFIELDS;
|
|
// The BMP format is always little endian, these masks stay the same
|
|
bV4RedMask = 0x00ff0000;
|
|
bV4GreenMask = 0x0000ff00;
|
|
bV4BlueMask = 0x000000ff;
|
|
bV4AlphaMask = 0xff000000;
|
|
bV4CSType = LCS_sRGB;
|
|
bV4GammaRed = 0;
|
|
bV4GammaGreen = 0;
|
|
bV4GammaBlue = 0;
|
|
// Version 5 values
|
|
bV5Intent = LCS_GM_GRAPHICS;
|
|
bV5ProfileData = 0;
|
|
bV5ProfileSize = 0;
|
|
bV5Reserved = 0;
|
|
}
|
|
|
|
// Write the BMP info values
|
|
if (!SDL_WriteU32LE(dst, biSize) ||
|
|
!SDL_WriteS32LE(dst, biWidth) ||
|
|
!SDL_WriteS32LE(dst, biHeight) ||
|
|
!SDL_WriteU16LE(dst, biPlanes) ||
|
|
!SDL_WriteU16LE(dst, biBitCount) ||
|
|
!SDL_WriteU32LE(dst, biCompression) ||
|
|
!SDL_WriteU32LE(dst, biSizeImage) ||
|
|
!SDL_WriteU32LE(dst, biXPelsPerMeter) ||
|
|
!SDL_WriteU32LE(dst, biYPelsPerMeter) ||
|
|
!SDL_WriteU32LE(dst, biClrUsed) ||
|
|
!SDL_WriteU32LE(dst, biClrImportant)) {
|
|
goto done;
|
|
}
|
|
|
|
// Write the BMP info values
|
|
if (save32bit && !saveLegacyBMP) {
|
|
// Version 4 values
|
|
if (!SDL_WriteU32LE(dst, bV4RedMask) ||
|
|
!SDL_WriteU32LE(dst, bV4GreenMask) ||
|
|
!SDL_WriteU32LE(dst, bV4BlueMask) ||
|
|
!SDL_WriteU32LE(dst, bV4AlphaMask) ||
|
|
!SDL_WriteU32LE(dst, bV4CSType)) {
|
|
goto done;
|
|
}
|
|
for (i = 0; i < 3 * 3; i++) {
|
|
if (!SDL_WriteU32LE(dst, bV4Endpoints[i])) {
|
|
goto done;
|
|
}
|
|
}
|
|
if (!SDL_WriteU32LE(dst, bV4GammaRed) ||
|
|
!SDL_WriteU32LE(dst, bV4GammaGreen) ||
|
|
!SDL_WriteU32LE(dst, bV4GammaBlue)) {
|
|
goto done;
|
|
}
|
|
// Version 5 values
|
|
if (!SDL_WriteU32LE(dst, bV5Intent) ||
|
|
!SDL_WriteU32LE(dst, bV5ProfileData) ||
|
|
!SDL_WriteU32LE(dst, bV5ProfileSize) ||
|
|
!SDL_WriteU32LE(dst, bV5Reserved)) {
|
|
goto done;
|
|
}
|
|
}
|
|
|
|
// Write the palette (in BGR color order)
|
|
if (intermediate_surface->palette) {
|
|
SDL_Color *colors;
|
|
int ncolors;
|
|
|
|
colors = intermediate_surface->palette->colors;
|
|
ncolors = intermediate_surface->palette->ncolors;
|
|
for (i = 0; i < ncolors; ++i) {
|
|
if (!SDL_WriteU8(dst, colors[i].b) ||
|
|
!SDL_WriteU8(dst, colors[i].g) ||
|
|
!SDL_WriteU8(dst, colors[i].r) ||
|
|
!SDL_WriteU8(dst, colors[i].a)) {
|
|
goto done;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Write the bitmap offset
|
|
bfOffBits = (Uint32)(SDL_TellIO(dst) - fp_offset);
|
|
if (SDL_SeekIO(dst, fp_offset + 10, SDL_IO_SEEK_SET) < 0) {
|
|
goto done;
|
|
}
|
|
if (!SDL_WriteU32LE(dst, bfOffBits)) {
|
|
goto done;
|
|
}
|
|
if (SDL_SeekIO(dst, fp_offset + bfOffBits, SDL_IO_SEEK_SET) < 0) {
|
|
goto done;
|
|
}
|
|
|
|
// Write the bitmap image upside down
|
|
bits = (Uint8 *)intermediate_surface->pixels + (intermediate_surface->h * intermediate_surface->pitch);
|
|
pad = ((bw % 4) ? (4 - (bw % 4)) : 0);
|
|
while (bits > (Uint8 *)intermediate_surface->pixels) {
|
|
bits -= intermediate_surface->pitch;
|
|
if (SDL_WriteIO(dst, bits, bw) != bw) {
|
|
goto done;
|
|
}
|
|
if (pad) {
|
|
const Uint8 padbyte = 0;
|
|
for (i = 0; i < pad; ++i) {
|
|
if (!SDL_WriteU8(dst, padbyte)) {
|
|
goto done;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Write the BMP file size
|
|
new_offset = SDL_TellIO(dst);
|
|
if (new_offset < 0) {
|
|
goto done;
|
|
}
|
|
bfSize = (Uint32)(new_offset - fp_offset);
|
|
if (SDL_SeekIO(dst, fp_offset + 2, SDL_IO_SEEK_SET) < 0) {
|
|
goto done;
|
|
}
|
|
if (!SDL_WriteU32LE(dst, bfSize)) {
|
|
goto done;
|
|
}
|
|
if (SDL_SeekIO(dst, fp_offset + bfSize, SDL_IO_SEEK_SET) < 0) {
|
|
goto done;
|
|
}
|
|
|
|
// Close it up..
|
|
SDL_UnlockSurface(intermediate_surface);
|
|
|
|
was_error = false;
|
|
}
|
|
|
|
done:
|
|
if (intermediate_surface && intermediate_surface != surface) {
|
|
SDL_DestroySurface(intermediate_surface);
|
|
}
|
|
if (closeio && dst) {
|
|
if (!SDL_CloseIO(dst)) {
|
|
was_error = true;
|
|
}
|
|
}
|
|
if (was_error) {
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool SDL_SaveBMP(SDL_Surface *surface, const char *file)
|
|
{
|
|
SDL_IOStream *stream = SDL_IOFromFile(file, "wb");
|
|
if (!stream) {
|
|
return false;
|
|
}
|
|
return SDL_SaveBMP_IO(surface, stream, true);
|
|
}
|