/project/jni/sdl_image/IMG.c

  1/*
  2  SDL_image:  An example image loading library for use with SDL
  3  Copyright (C) 1997-2012 Sam Lantinga <slouken@libsdl.org>
  4
  5  This software is provided 'as-is', without any express or implied
  6  warranty.  In no event will the authors be held liable for any damages
  7  arising from the use of this software.
  8
  9  Permission is granted to anyone to use this software for any purpose,
 10  including commercial applications, and to alter it and redistribute it
 11  freely, subject to the following restrictions:
 12
 13  1. The origin of this software must not be misrepresented; you must not
 14     claim that you wrote the original software. If you use this software
 15     in a product, an acknowledgment in the product documentation would be
 16     appreciated but is not required.
 17  2. Altered source versions must be plainly marked as such, and must not be
 18     misrepresented as being the original software.
 19  3. This notice may not be removed or altered from any source distribution.
 20*/
 21
 22/* A simple library to load images of various formats as SDL surfaces */
 23
 24#include <stdio.h>
 25#include <string.h>
 26#include <ctype.h>
 27
 28#include "SDL_image.h"
 29
 30#define ARRAYSIZE(a) (sizeof(a) / sizeof((a)[0]))
 31
 32/* Table of image detection and loading functions */
 33static struct {
 34	char *type;
 35	int (SDLCALL *is)(SDL_RWops *src);
 36	SDL_Surface *(SDLCALL *load)(SDL_RWops *src);
 37} supported[] = {
 38	/* keep magicless formats first */
 39	{ "TGA", NULL,      IMG_LoadTGA_RW },
 40	{ "CUR", IMG_isCUR, IMG_LoadCUR_RW },
 41	{ "ICO", IMG_isICO, IMG_LoadICO_RW },
 42	{ "BMP", IMG_isBMP, IMG_LoadBMP_RW },
 43	{ "GIF", IMG_isGIF, IMG_LoadGIF_RW },
 44	{ "JPG", IMG_isJPG, IMG_LoadJPG_RW },
 45	{ "LBM", IMG_isLBM, IMG_LoadLBM_RW },
 46	{ "PCX", IMG_isPCX, IMG_LoadPCX_RW },
 47	{ "PNG", IMG_isPNG, IMG_LoadPNG_RW },
 48	{ "PNM", IMG_isPNM, IMG_LoadPNM_RW }, /* P[BGP]M share code */
 49	{ "TIF", IMG_isTIF, IMG_LoadTIF_RW },
 50	{ "XCF", IMG_isXCF, IMG_LoadXCF_RW },
 51	{ "XPM", IMG_isXPM, IMG_LoadXPM_RW },
 52	{ "XV",  IMG_isXV,  IMG_LoadXV_RW  },
 53	{ "WEBP", IMG_isWEBP, IMG_LoadWEBP_RW },
 54};
 55
 56const SDL_version *IMG_Linked_Version(void)
 57{
 58	static SDL_version linked_version;
 59	SDL_IMAGE_VERSION(&linked_version);
 60	return(&linked_version);
 61}
 62
 63extern int IMG_InitJPG();
 64extern void IMG_QuitJPG();
 65extern int IMG_InitPNG();
 66extern void IMG_QuitPNG();
 67extern int IMG_InitTIF();
 68extern void IMG_QuitTIF();
 69
 70extern int IMG_InitWEBP();
 71extern void IMG_QuitWEBP();
 72
 73static int initialized = 0;
 74
 75int IMG_Init(int flags)
 76{
 77	int result = 0;
 78
 79	if (flags & IMG_INIT_JPG) {
 80		if ((initialized & IMG_INIT_JPG) || IMG_InitJPG() == 0) {
 81			result |= IMG_INIT_JPG;
 82		}
 83	}
 84	if (flags & IMG_INIT_PNG) {
 85		if ((initialized & IMG_INIT_PNG) || IMG_InitPNG() == 0) {
 86			result |= IMG_INIT_PNG;
 87		}
 88	}
 89	if (flags & IMG_INIT_TIF) {
 90		if ((initialized & IMG_INIT_TIF) || IMG_InitTIF() == 0) {
 91			result |= IMG_INIT_TIF;
 92		}
 93	}
 94	if (flags & IMG_INIT_WEBP) {
 95		if ((initialized & IMG_INIT_WEBP) || IMG_InitWEBP() == 0) {
 96			result |= IMG_INIT_WEBP;
 97		}
 98	}
 99	initialized |= result;
100
101	return (initialized);
102}
103
104void IMG_Quit()
105{
106	if (initialized & IMG_INIT_JPG) {
107		IMG_QuitJPG();
108	}
109	if (initialized & IMG_INIT_PNG) {
110		IMG_QuitPNG();
111	}
112	if (initialized & IMG_INIT_TIF) {
113		IMG_QuitTIF();
114	}
115	if (initialized & IMG_INIT_WEBP) {
116		IMG_QuitWEBP();
117	}
118	initialized = 0;
119}
120
121#if !defined(__APPLE__) || defined(SDL_IMAGE_USE_COMMON_BACKEND)
122/* Load an image from a file */
123SDL_Surface *IMG_Load(const char *file)
124{
125    SDL_RWops *src = SDL_RWFromFile(file, "rb");
126    char *ext = strrchr(file, '.');
127    if(ext) {
128        ext++;
129    }
130    if(!src) {
131        /* The error message has been set in SDL_RWFromFile */
132        return NULL;
133    }
134    return IMG_LoadTyped_RW(src, 1, ext);
135}
136#endif
137
138/* Load an image from an SDL datasource (for compatibility) */
139SDL_Surface *IMG_Load_RW(SDL_RWops *src, int freesrc)
140{
141    return IMG_LoadTyped_RW(src, freesrc, NULL);
142}
143
144/* Portable case-insensitive string compare function */
145static int IMG_string_equals(const char *str1, const char *str2)
146{
147	while ( *str1 && *str2 ) {
148		if ( toupper((unsigned char)*str1) !=
149		     toupper((unsigned char)*str2) )
150			break;
151		++str1;
152		++str2;
153	}
154	return (!*str1 && !*str2);
155}
156
157/* Load an image from an SDL datasource, optionally specifying the type */
158SDL_Surface *IMG_LoadTyped_RW(SDL_RWops *src, int freesrc, const char *type)
159{
160	int i;
161	SDL_Surface *image;
162
163	/* Make sure there is something to do.. */
164	if ( src == NULL ) {
165		IMG_SetError("Passed a NULL data source");
166		return(NULL);
167	}
168
169	/* See whether or not this data source can handle seeking */
170	if ( SDL_RWseek(src, 0, RW_SEEK_CUR) < 0 ) {
171		IMG_SetError("Can't seek in this data source");
172		if(freesrc)
173			SDL_RWclose(src);
174		return(NULL);
175	}
176
177	/* Detect the type of image being loaded */
178	image = NULL;
179	for ( i=0; i < ARRAYSIZE(supported); ++i ) {
180		if(supported[i].is) {
181			if(!supported[i].is(src))
182				continue;
183		} else {
184			/* magicless format */
185			if(!type
186			   || !IMG_string_equals(type, supported[i].type))
187				continue;
188		}
189#ifdef DEBUG_IMGLIB
190		fprintf(stderr, "IMGLIB: Loading image as %s\n",
191			supported[i].type);
192#endif
193		image = supported[i].load(src);
194		if(freesrc)
195			SDL_RWclose(src);
196		return image;
197	}
198
199	if ( freesrc ) {
200		SDL_RWclose(src);
201	}
202	IMG_SetError("Unsupported image format");
203	return NULL;
204}
205
206#if (SDL_VERSION_ATLEAST(1,3,0))
207SDL_Texture *IMG_LoadTexture(SDL_Renderer *renderer, const char *file)
208{
209    SDL_Texture *texture = NULL;
210    SDL_Surface *surface = IMG_Load(file);
211    if (surface) {
212        texture = SDL_CreateTextureFromSurface(renderer, surface);
213        SDL_FreeSurface(surface);
214    }
215    return texture;
216}
217
218SDL_Texture *IMG_LoadTexture_RW(SDL_Renderer *renderer, SDL_RWops *src, int freesrc)
219{
220    SDL_Texture *texture = NULL;
221    SDL_Surface *surface = IMG_Load_RW(src, freesrc);
222    if (surface) {
223        texture = SDL_CreateTextureFromSurface(renderer, surface);
224        SDL_FreeSurface(surface);
225    }
226    return texture;
227}
228
229SDL_Texture *IMG_LoadTextureTyped_RW(SDL_Renderer *renderer, SDL_RWops *src, int freesrc, const char *type)
230{
231    SDL_Texture *texture = NULL;
232    SDL_Surface *surface = IMG_LoadTyped_RW(src, freesrc, type);
233    if (surface) {
234        texture = SDL_CreateTextureFromSurface(renderer, surface);
235        SDL_FreeSurface(surface);
236    }
237    return texture;
238}
239#endif
240
241/* Invert the alpha of a surface for use with OpenGL
242   This function is a no-op and only kept for backwards compatibility.
243 */
244int IMG_InvertAlpha(int on)
245{
246    return 1;
247}