cocoaTouch/otherSrc/IMG_png.c
changeset 2698 90585aba87ad
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cocoaTouch/otherSrc/IMG_png.c	Sat Jan 16 17:30:37 2010 +0000
@@ -0,0 +1,502 @@
+/*
+    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
+*/
+
+/* This is a PNG image file loading framework */
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "SDL_image.h"
+
+
+/*=============================================================================
+        File: SDL_png.c
+     Purpose: A PNG loader and saver for the SDL library      
+    Revision: 
+  Created by: Philippe Lavoie          (2 November 1998)
+              lavoie@zeus.genie.uottawa.ca
+ Modified by: 
+
+ Copyright notice:
+          Copyright (C) 1998 Philippe Lavoie
+ 
+          This library is free software; you can redistribute it and/or
+          modify it under the terms of the GNU Library General Public
+          License as published by the Free Software Foundation; either
+          version 2 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
+          Library General Public License for more details.
+ 
+          You should have received a copy of the GNU Library General Public
+          License along with this library; if not, write to the Free
+          Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+    Comments: The load and save routine are basically the ones you can find
+             in the example.c file from the libpng distribution.
+
+  Changes:
+    5/17/99 - Modified to use the new SDL data sources - Sam Lantinga
+
+=============================================================================*/
+
+#include "SDL_endian.h"
+
+#ifdef macintosh
+#define MACOS
+#endif
+#include "png.h"
+
+
+static struct {
+	int loaded;
+	void *handle;
+	png_infop (*png_create_info_struct) (png_structp png_ptr);
+	png_structp (*png_create_read_struct) (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warn_fn);
+	void (*png_destroy_read_struct) (png_structpp png_ptr_ptr, png_infopp info_ptr_ptr, png_infopp end_info_ptr_ptr);
+	png_uint_32 (*png_get_IHDR) (png_structp png_ptr, png_infop info_ptr, png_uint_32 *width, png_uint_32 *height, int *bit_depth, int *color_type, int *interlace_method, int *compression_method, int *filter_method);
+	png_voidp (*png_get_io_ptr) (png_structp png_ptr);
+	png_uint_32 (*png_get_tRNS) (png_structp png_ptr, png_infop info_ptr, png_bytep *trans, int *num_trans, png_color_16p *trans_values);
+	png_uint_32 (*png_get_valid) (png_structp png_ptr, png_infop info_ptr, png_uint_32 flag);
+	void (*png_read_image) (png_structp png_ptr, png_bytepp image);
+	void (*png_read_info) (png_structp png_ptr, png_infop info_ptr);
+	void (*png_read_update_info) (png_structp png_ptr, png_infop info_ptr);
+	void (*png_set_expand) (png_structp png_ptr);
+	void (*png_set_gray_to_rgb) (png_structp png_ptr);
+	void (*png_set_packing) (png_structp png_ptr);
+	void (*png_set_read_fn) (png_structp png_ptr, png_voidp io_ptr, png_rw_ptr read_data_fn);
+	void (*png_set_strip_16) (png_structp png_ptr);
+	int (*png_sig_cmp) (png_bytep sig, png_size_t start, png_size_t num_to_check);
+} lib;
+
+#ifdef LOAD_PNG_DYNAMIC
+int IMG_InitPNG()
+{
+	if ( lib.loaded == 0 ) {
+		lib.handle = SDL_LoadObject(LOAD_PNG_DYNAMIC);
+		if ( lib.handle == NULL ) {
+			return -1;
+		}
+		lib.png_create_info_struct =
+			(png_infop (*) (png_structp))
+			SDL_LoadFunction(lib.handle, "png_create_info_struct");
+		if ( lib.png_create_info_struct == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_create_read_struct =
+			(png_structp (*) (png_const_charp, png_voidp, png_error_ptr, png_error_ptr))
+			SDL_LoadFunction(lib.handle, "png_create_read_struct");
+		if ( lib.png_create_read_struct == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_destroy_read_struct =
+			(void (*) (png_structpp, png_infopp, png_infopp))
+			SDL_LoadFunction(lib.handle, "png_destroy_read_struct");
+		if ( lib.png_destroy_read_struct == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_get_IHDR =
+			(png_uint_32 (*) (png_structp, png_infop, png_uint_32 *, png_uint_32 *, int *, int *, int *, int *, int *))
+			SDL_LoadFunction(lib.handle, "png_get_IHDR");
+		if ( lib.png_get_IHDR == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_get_io_ptr =
+			(png_voidp (*) (png_structp))
+			SDL_LoadFunction(lib.handle, "png_get_io_ptr");
+		if ( lib.png_get_io_ptr == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_get_tRNS =
+			(png_uint_32 (*) (png_structp, png_infop, png_bytep *, int *, png_color_16p *))
+			SDL_LoadFunction(lib.handle, "png_get_tRNS");
+		if ( lib.png_get_tRNS == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_get_valid =
+			(png_uint_32 (*) (png_structp, png_infop, png_uint_32))
+			SDL_LoadFunction(lib.handle, "png_get_valid");
+		if ( lib.png_get_valid == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_read_image =
+			(void (*) (png_structp, png_bytepp))
+			SDL_LoadFunction(lib.handle, "png_read_image");
+		if ( lib.png_read_image == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_read_info =
+			(void (*) (png_structp, png_infop))
+			SDL_LoadFunction(lib.handle, "png_read_info");
+		if ( lib.png_read_info == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_read_update_info =
+			(void (*) (png_structp, png_infop))
+			SDL_LoadFunction(lib.handle, "png_read_update_info");
+		if ( lib.png_read_update_info == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_set_expand =
+			(void (*) (png_structp))
+			SDL_LoadFunction(lib.handle, "png_set_expand");
+		if ( lib.png_set_expand == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_set_gray_to_rgb =
+			(void (*) (png_structp))
+			SDL_LoadFunction(lib.handle, "png_set_gray_to_rgb");
+		if ( lib.png_set_gray_to_rgb == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_set_packing =
+			(void (*) (png_structp))
+			SDL_LoadFunction(lib.handle, "png_set_packing");
+		if ( lib.png_set_packing == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_set_read_fn =
+			(void (*) (png_structp, png_voidp, png_rw_ptr))
+			SDL_LoadFunction(lib.handle, "png_set_read_fn");
+		if ( lib.png_set_read_fn == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_set_strip_16 =
+			(void (*) (png_structp))
+			SDL_LoadFunction(lib.handle, "png_set_strip_16");
+		if ( lib.png_set_strip_16 == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+		lib.png_sig_cmp =
+			(int (*) (png_bytep, png_size_t, png_size_t))
+			SDL_LoadFunction(lib.handle, "png_sig_cmp");
+		if ( lib.png_sig_cmp == NULL ) {
+			SDL_UnloadObject(lib.handle);
+			return -1;
+		}
+	}
+	++lib.loaded;
+
+	return 0;
+}
+void IMG_QuitPNG()
+{
+	if ( lib.loaded == 0 ) {
+		return;
+	}
+	if ( lib.loaded == 1 ) {
+		SDL_UnloadObject(lib.handle);
+	}
+	--lib.loaded;
+}
+#else
+int IMG_InitPNG()
+{
+	if ( lib.loaded == 0 ) {
+		lib.png_create_info_struct = png_create_info_struct;
+		lib.png_create_read_struct = png_create_read_struct;
+		lib.png_destroy_read_struct = png_destroy_read_struct;
+		lib.png_get_IHDR = png_get_IHDR;
+		lib.png_get_io_ptr = png_get_io_ptr;
+		lib.png_get_tRNS = png_get_tRNS;
+		lib.png_get_valid = png_get_valid;
+		lib.png_read_image = png_read_image;
+		lib.png_read_info = png_read_info;
+		lib.png_read_update_info = png_read_update_info;
+		lib.png_set_expand = png_set_expand;
+		lib.png_set_gray_to_rgb = png_set_gray_to_rgb;
+		lib.png_set_packing = png_set_packing;
+		lib.png_set_read_fn = png_set_read_fn;
+		lib.png_set_strip_16 = png_set_strip_16;
+		lib.png_sig_cmp = png_sig_cmp;
+	}
+	++lib.loaded;
+
+	return 0;
+}
+void IMG_QuitPNG()
+{
+	if ( lib.loaded == 0 ) {
+		return;
+	}
+	if ( lib.loaded == 1 ) {
+	}
+	--lib.loaded;
+}
+#endif /* LOAD_PNG_DYNAMIC */
+
+/* See if an image is contained in a data source */
+int IMG_isPNG(SDL_RWops *src)
+{
+	int start;
+	int is_PNG;
+	Uint8 magic[4];
+
+	if ( !src )
+		return 0;
+	start = SDL_RWtell(src);
+	is_PNG = 0;
+	if ( SDL_RWread(src, magic, 1, sizeof(magic)) == sizeof(magic) ) {
+                if ( magic[0] == 0x89 &&
+                     magic[1] == 'P' &&
+                     magic[2] == 'N' &&
+                     magic[3] == 'G' ) {
+			is_PNG = 1;
+		}
+	}
+	SDL_RWseek(src, start, RW_SEEK_SET);
+	return(is_PNG);
+}
+
+/* Load a PNG type image from an SDL datasource */
+static void png_read_data(png_structp ctx, png_bytep area, png_size_t size)
+{
+	SDL_RWops *src;
+
+	src = (SDL_RWops *)lib.png_get_io_ptr(ctx);
+	SDL_RWread(src, area, size, 1);
+}
+SDL_Surface *IMG_LoadPNG_RW(SDL_RWops *src)
+{
+	int start;
+	const char *error;
+	SDL_Surface *volatile surface;
+	png_structp png_ptr;
+	png_infop info_ptr;
+	png_uint_32 width, height;
+	int bit_depth, color_type, interlace_type;
+	Uint32 Rmask;
+	Uint32 Gmask;
+	Uint32 Bmask;
+	Uint32 Amask;
+	SDL_Palette *palette;
+	png_bytep *volatile row_pointers;
+	int row, i;
+	volatile int ckey = -1;
+	png_color_16 *transv;
+
+	if ( !src ) {
+		/* The error message has been set in SDL_RWFromFile */
+		return NULL;
+	}
+	start = SDL_RWtell(src);
+
+	if ( !IMG_Init(IMG_INIT_PNG) ) {
+		return NULL;
+	}
+
+	/* Initialize the data we will clean up when we're done */
+	error = NULL;
+	png_ptr = NULL; info_ptr = NULL; row_pointers = NULL; surface = NULL;
+
+	/* Create the PNG loading context structure */
+	png_ptr = lib.png_create_read_struct(PNG_LIBPNG_VER_STRING,
+					  NULL,NULL,NULL);
+	if (png_ptr == NULL){
+		error = "Couldn't allocate memory for PNG file or incompatible PNG dll";
+		goto done;
+	}
+
+	 /* Allocate/initialize the memory for image information.  REQUIRED. */
+	info_ptr = lib.png_create_info_struct(png_ptr);
+	if (info_ptr == NULL) {
+		error = "Couldn't create image information for PNG file";
+		goto done;
+	}
+
+	/* Set error handling if you are using setjmp/longjmp method (this is
+	 * the normal method of doing things with libpng).  REQUIRED unless you
+	 * set up your own error handlers in png_create_read_struct() earlier.
+	 */
+	if ( setjmp(png_ptr->jmpbuf) ) {
+		error = "Error reading the PNG file.";
+		goto done;
+	}
+
+	/* Set up the input control */
+	lib.png_set_read_fn(png_ptr, src, png_read_data);
+
+	/* Read PNG header info */
+	lib.png_read_info(png_ptr, info_ptr);
+	lib.png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth,
+			&color_type, &interlace_type, NULL, NULL);
+
+	/* tell libpng to strip 16 bit/color files down to 8 bits/color */
+	lib.png_set_strip_16(png_ptr) ;
+
+	/* Extract multiple pixels with bit depths of 1, 2, and 4 from a single
+	 * byte into separate bytes (useful for paletted and grayscale images).
+	 */
+	lib.png_set_packing(png_ptr);
+
+	/* scale greyscale values to the range 0..255 */
+	if(color_type == PNG_COLOR_TYPE_GRAY)
+		lib.png_set_expand(png_ptr);
+
+	/* For images with a single "transparent colour", set colour key;
+	   if more than one index has transparency, or if partially transparent
+	   entries exist, use full alpha channel */
+	if (lib.png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
+	        int num_trans;
+		Uint8 *trans;
+		lib.png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans,
+			     &transv);
+		if(color_type == PNG_COLOR_TYPE_PALETTE) {
+		    /* Check if all tRNS entries are opaque except one */
+		    int t = -1;
+		    for(i = 0; i < num_trans; i++)
+			if(trans[i] == 0) {
+			    if(t >= 0)
+				break;
+			    t = i;
+			} else if(trans[i] != 255)
+			    break;
+		    if(i == num_trans) {
+			/* exactly one transparent index */
+			ckey = t;
+		    } else {
+			/* more than one transparent index, or translucency */
+			lib.png_set_expand(png_ptr);
+		    }
+		} else
+		    ckey = 0; /* actual value will be set later */
+	}
+
+	if ( color_type == PNG_COLOR_TYPE_GRAY_ALPHA )
+		lib.png_set_gray_to_rgb(png_ptr);
+
+	lib.png_read_update_info(png_ptr, info_ptr);
+
+	lib.png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth,
+			&color_type, &interlace_type, NULL, NULL);
+
+	/* Allocate the SDL surface to hold the image */
+	Rmask = Gmask = Bmask = Amask = 0 ; 
+	if ( color_type != PNG_COLOR_TYPE_PALETTE ) {
+		if ( SDL_BYTEORDER == SDL_LIL_ENDIAN ) {
+			Rmask = 0x000000FF;
+			Gmask = 0x0000FF00;
+			Bmask = 0x00FF0000;
+			Amask = (info_ptr->channels == 4) ? 0xFF000000 : 0;
+		} else {
+		        int s = (info_ptr->channels == 4) ? 0 : 8;
+			Rmask = 0xFF000000 >> s;
+			Gmask = 0x00FF0000 >> s;
+			Bmask = 0x0000FF00 >> s;
+			Amask = 0x000000FF >> s;
+		}
+	}
+	surface = SDL_AllocSurface(SDL_SWSURFACE, width, height,
+			bit_depth*info_ptr->channels, Rmask,Gmask,Bmask,Amask);
+	if ( surface == NULL ) {
+		error = "Out of memory";
+		goto done;
+	}
+
+	if(ckey != -1) {
+	        if(color_type != PNG_COLOR_TYPE_PALETTE)
+			/* FIXME: Should these be truncated or shifted down? */
+		        ckey = SDL_MapRGB(surface->format,
+			                 (Uint8)transv->red,
+			                 (Uint8)transv->green,
+			                 (Uint8)transv->blue);
+	        SDL_SetColorKey(surface, SDL_SRCCOLORKEY, ckey);
+	}
+
+	/* Create the array of pointers to image data */
+	row_pointers = (png_bytep*) malloc(sizeof(png_bytep)*height);
+	if ( (row_pointers == NULL) ) {
+		error = "Out of memory";
+		goto done;
+	}
+	for (row = 0; row < (int)height; row++) {
+		row_pointers[row] = (png_bytep)
+				(Uint8 *)surface->pixels + row*surface->pitch;
+	}
+
+	/* Read the entire image in one go */
+	lib.png_read_image(png_ptr, row_pointers);
+
+	/* and we're done!  (png_read_end() can be omitted if no processing of
+	 * post-IDAT text/time/etc. is desired)
+	 * In some cases it can't read PNG's created by some popular programs (ACDSEE),
+	 * we do not want to process comments, so we omit png_read_end
+
+	lib.png_read_end(png_ptr, info_ptr);
+	*/
+
+	/* Load the palette, if any */
+	palette = surface->format->palette;
+	if ( palette ) {
+	    if(color_type == PNG_COLOR_TYPE_GRAY) {
+			palette->ncolors = 256;
+			for(i = 0; i < 256; i++) {
+				palette->colors[i].r = i;
+				palette->colors[i].g = i;
+				palette->colors[i].b = i;
+			}
+		} else if (info_ptr->num_palette > 0 ) {
+			palette->ncolors = info_ptr->num_palette; 
+			for( i=0; i<info_ptr->num_palette; ++i ) {
+				palette->colors[i].b = info_ptr->palette[i].blue;
+				palette->colors[i].g = info_ptr->palette[i].green;
+				palette->colors[i].r = info_ptr->palette[i].red;
+			}
+	    }
+	}
+
+done:	/* Clean up and return */
+	if ( png_ptr ) {
+		lib.png_destroy_read_struct(&png_ptr,
+		                        info_ptr ? &info_ptr : (png_infopp)0,
+								(png_infopp)0);
+	}
+	if ( row_pointers ) {
+		free(row_pointers);
+	}
+	if ( error ) {
+		SDL_RWseek(src, start, RW_SEEK_SET);
+		if ( surface ) {
+			SDL_FreeSurface(surface);
+			surface = NULL;
+		}
+		IMG_SetError(error);
+	}
+	return(surface); 
+}