155 lines
4.3 KiB
C
155 lines
4.3 KiB
C
/*
|
|
SDL_image: An example image loading library for use with SDL
|
|
Copyright (C) 1997-2009 Sam Lantinga
|
|
|
|
This library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
This library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with this library; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
|
|
Sam Lantinga
|
|
slouken@libsdl.org
|
|
*/
|
|
|
|
/* A simple library to load images of various formats as SDL surfaces */
|
|
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <ctype.h>
|
|
|
|
#include "SDL_image.h"
|
|
|
|
#define ARRAYSIZE(a) (sizeof(a) / sizeof((a)[0]))
|
|
|
|
/* Table of image detection and loading functions */
|
|
static struct {
|
|
char *type;
|
|
int (SDLCALL *is)(SDL_RWops *src);
|
|
SDL_Surface *(SDLCALL *load)(SDL_RWops *src);
|
|
} supported[] = {
|
|
/* keep magicless formats first */
|
|
{ "TGA", NULL, IMG_LoadTGA_RW },
|
|
{ "CUR", IMG_isCUR, IMG_LoadCUR_RW },
|
|
{ "ICO", IMG_isICO, IMG_LoadICO_RW },
|
|
{ "BMP", IMG_isBMP, IMG_LoadBMP_RW },
|
|
{ "GIF", IMG_isGIF, IMG_LoadGIF_RW },
|
|
{ "JPG", IMG_isJPG, IMG_LoadJPG_RW },
|
|
{ "LBM", IMG_isLBM, IMG_LoadLBM_RW },
|
|
{ "PCX", IMG_isPCX, IMG_LoadPCX_RW },
|
|
{ "PNG", IMG_isPNG, IMG_LoadPNG_RW },
|
|
{ "PNM", IMG_isPNM, IMG_LoadPNM_RW }, /* P[BGP]M share code */
|
|
{ "TIF", IMG_isTIF, IMG_LoadTIF_RW },
|
|
{ "XCF", IMG_isXCF, IMG_LoadXCF_RW },
|
|
{ "XPM", IMG_isXPM, IMG_LoadXPM_RW },
|
|
{ "XV", IMG_isXV, IMG_LoadXV_RW }
|
|
};
|
|
|
|
const SDL_version *IMG_Linked_Version(void)
|
|
{
|
|
static SDL_version linked_version;
|
|
SDL_IMAGE_VERSION(&linked_version);
|
|
return(&linked_version);
|
|
}
|
|
|
|
#if !defined(__APPLE__) || defined(SDL_IMAGE_USE_COMMON_BACKEND)
|
|
/* Load an image from a file */
|
|
SDL_Surface *IMG_Load(const char *file)
|
|
{
|
|
SDL_RWops *src = SDL_RWFromFile(file, "rb");
|
|
char *ext = strrchr(file, '.');
|
|
if(ext) {
|
|
ext++;
|
|
}
|
|
if(!src) {
|
|
/* The error message has been set in SDL_RWFromFile */
|
|
return NULL;
|
|
}
|
|
return IMG_LoadTyped_RW(src, 1, ext);
|
|
}
|
|
#endif
|
|
|
|
/* Load an image from an SDL datasource (for compatibility) */
|
|
SDL_Surface *IMG_Load_RW(SDL_RWops *src, int freesrc)
|
|
{
|
|
return IMG_LoadTyped_RW(src, freesrc, NULL);
|
|
}
|
|
|
|
/* Portable case-insensitive string compare function */
|
|
static int IMG_string_equals(const char *str1, const char *str2)
|
|
{
|
|
while ( *str1 && *str2 ) {
|
|
if ( toupper((unsigned char)*str1) !=
|
|
toupper((unsigned char)*str2) )
|
|
break;
|
|
++str1;
|
|
++str2;
|
|
}
|
|
return (!*str1 && !*str2);
|
|
}
|
|
|
|
/* Load an image from an SDL datasource, optionally specifying the type */
|
|
SDL_Surface *IMG_LoadTyped_RW(SDL_RWops *src, int freesrc, char *type)
|
|
{
|
|
int i;
|
|
SDL_Surface *image;
|
|
|
|
/* Make sure there is something to do.. */
|
|
if ( src == NULL ) {
|
|
IMG_SetError("Passed a NULL data source");
|
|
return(NULL);
|
|
}
|
|
|
|
/* See whether or not this data source can handle seeking */
|
|
if ( SDL_RWseek(src, 0, SEEK_CUR) < 0 ) {
|
|
IMG_SetError("Can't seek in this data source");
|
|
if(freesrc)
|
|
SDL_RWclose(src);
|
|
return(NULL);
|
|
}
|
|
|
|
/* Detect the type of image being loaded */
|
|
image = NULL;
|
|
for ( i=0; i < ARRAYSIZE(supported); ++i ) {
|
|
if(supported[i].is) {
|
|
if(!supported[i].is(src))
|
|
continue;
|
|
} else {
|
|
/* magicless format */
|
|
if(!type
|
|
|| !IMG_string_equals(type, supported[i].type))
|
|
continue;
|
|
}
|
|
#ifdef DEBUG_IMGLIB
|
|
fprintf(stderr, "IMGLIB: Loading image as %s\n",
|
|
supported[i].type);
|
|
#endif
|
|
image = supported[i].load(src);
|
|
if(freesrc)
|
|
SDL_RWclose(src);
|
|
return image;
|
|
}
|
|
|
|
if ( freesrc ) {
|
|
SDL_RWclose(src);
|
|
}
|
|
IMG_SetError("Unsupported image format");
|
|
return NULL;
|
|
}
|
|
|
|
/* Invert the alpha of a surface for use with OpenGL
|
|
This function is a no-op and only kept for backwards compatibility.
|
|
*/
|
|
int IMG_InvertAlpha(int on)
|
|
{
|
|
return 1;
|
|
}
|