dolphin/Source/Core/DolphinWX/Src/Android/TextureLoader.cpp

167 lines
4.3 KiB
C++

// Copyright (C) 2003 Dolphin Project.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0.
// This program 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 General Public License 2.0 for more details.
// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/
// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/
#include "GLInterface.h"
#include <png.h>
char* LoadPNG(const char *filename, u32 &width, u32 &height)
{
FILE *infile; /* PNG file pointer */
png_structp png_ptr; /* internally used by libpng */
png_infop info_ptr; /* user requested transforms */
char *image_data; /* raw png image data */
char sig[8]; /* PNG signature array */
/*char **row_pointers; */
int bit_depth;
int color_type;
png_uint_32 _width;
png_uint_32 _height;
unsigned int rowbytes; /* raw bytes at row n in image */
image_data = NULL;
unsigned int i;
png_bytepp row_pointers = NULL;
/* Open the file. */
infile = fopen(filename, "rb");
if (!infile)
return NULL;
/*
* 13.3 readpng_init()
*/
/* Check for the 8-byte signature */
fread(sig, 1, 8, infile);
if (!png_check_sig((unsigned char *) sig, 8)) {
fclose(infile);
return NULL;
}
/*
* Set up the PNG structs
*/
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!png_ptr) {
fclose(infile);
return NULL; /* out of memory */
}
info_ptr = png_create_info_struct(png_ptr);
if (!info_ptr) {
png_destroy_read_struct(&png_ptr, (png_infopp) NULL, (png_infopp) NULL);
fclose(infile);
return NULL; /* out of memory */
}
/*
* block to handle libpng errors,
* then check whether the PNG file had a bKGD chunk
*/
if (setjmp(png_jmpbuf(png_ptr))) {
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
fclose(infile);
return NULL;
}
/*
* takes our file stream pointer (infile) and
* stores it in the png_ptr struct for later use.
*/
/* png_ptr->io_ptr = (png_voidp)infile;*/
png_init_io(png_ptr, infile);
/*
* lets libpng know that we already checked the 8
* signature bytes, so it should not expect to find
* them at the current file pointer location
*/
png_set_sig_bytes(png_ptr, 8);
/* Read the image */
/*
* reads and processes not only the PNG file's IHDR chunk
* but also any other chunks up to the first IDAT
* (i.e., everything before the image data).
*/
/* read all the info up to the image data */
png_read_info(png_ptr, info_ptr);
png_get_IHDR(png_ptr, info_ptr, &_width, &_height, &bit_depth,
&color_type, NULL, NULL, NULL);
/* Set up some transforms. */
if (bit_depth > 8)
png_set_strip_16(png_ptr);
if (color_type == PNG_COLOR_TYPE_GRAY || color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
png_set_gray_to_rgb(png_ptr);
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_palette_to_rgb(png_ptr);
/* Update the png info struct.*/
png_read_update_info(png_ptr, info_ptr);
/* Rowsize in bytes. */
rowbytes = png_get_rowbytes(png_ptr, info_ptr);
/* Allocate the image_data buffer. */
if ((image_data = (char *) malloc(rowbytes * _height))==NULL) {
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
return NULL;
}
if ((row_pointers = (png_bytepp)malloc(_height*sizeof(png_bytep))) == NULL) {
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
free(image_data);
image_data = NULL;
return NULL;
}
/* set the individual row_pointers to point at the correct offsets */
for (i = 0; i < _height; ++i)
row_pointers[i] = (png_byte*)(image_data + i*rowbytes);
/* now we can go ahead and just read the whole image */
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) */
/* Clean up. */
free(row_pointers);
/* Clean up. */
png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
fclose(infile);
width = (u32)_width;
height = (u32)_height;
return image_data;
}