Files
lime/project/src/graphics/PNG.cpp
2014-07-27 14:25:20 -07:00

168 lines
3.5 KiB
C++

extern "C" {
#include <png.h>
#define PNG_SIG_SIZE 8
}
#include <graphics/Image.h>
#include <graphics/PNG.h>
#include <utils/FileIO.h>
namespace lime {
bool PNG::Decode (const char *path, Image *image) {
unsigned char png_sig[PNG_SIG_SIZE];
png_structp png_ptr;
png_infop info_ptr;
png_uint_32 width, height;
int bit_depth, color_type;
FILE *file = lime::fopen (path, "rb");
if (!file) return false;
// verify the PNG signature
int read = lime::fread (png_sig, PNG_SIG_SIZE, 1, file);
if (png_sig_cmp (png_sig, 0, PNG_SIG_SIZE)) {
lime::fclose (file);
return false;
}
if ((png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL)) == NULL) {
lime::fclose (file);
return false;
}
if ((info_ptr = png_create_info_struct (png_ptr)) == NULL) {
png_destroy_read_struct (&png_ptr, (png_infopp)NULL, (png_infopp)NULL);
lime::fclose (file);
return false;
}
// sets the point which libpng will jump back to in the case of an error
if (setjmp (png_jmpbuf (png_ptr))) {
png_destroy_read_struct (&png_ptr, &info_ptr, (png_infopp)NULL);
lime::fclose (file);
return false;
}
png_init_io (png_ptr, file);
png_set_sig_bytes (png_ptr, PNG_SIG_SIZE);
png_read_info (png_ptr, info_ptr);
width = png_get_image_width (png_ptr, info_ptr);
height = png_get_image_height (png_ptr, info_ptr);
color_type = png_get_color_type (png_ptr, info_ptr);
bit_depth = png_get_bit_depth (png_ptr, info_ptr);
png_set_expand (png_ptr);
png_set_filler (png_ptr, 0xff, PNG_FILLER_AFTER);
if (bit_depth == 16)
png_set_strip_16 (png_ptr);
int bpp = 4;
const unsigned int stride = width * bpp;
image->Resize(width, height, bpp);
png_bytepp row_ptrs = new png_bytep[height];
unsigned char *bytes = image->data->Bytes ();
for (size_t i = 0; i < height; i++) {
row_ptrs[i] = bytes + i * stride;
}
png_read_image (png_ptr, row_ptrs);
png_read_end (png_ptr, NULL);
delete[] row_ptrs;
png_destroy_read_struct (&png_ptr, &info_ptr, (png_infopp)NULL);
return true;
}
static bool Encode (Image *image, ByteArray *bytes) {
return true;
/*png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, user_error_fn, user_warning_fn);
if (!png_ptr)
return false;
png_infop info_ptr = png_create_info_struct(png_ptr);
if (!info_ptr)
return false;
if (setjmp(png_jmpbuf(png_ptr)))
{
png_destroy_write_struct(&png_ptr, &info_ptr );
return false;
}
QuickVec<uint8> out_buffer;
png_set_write_fn(png_ptr, &out_buffer, user_write_data, user_flush_data);
int w = inSurface->Width();
int h = inSurface->Height();
int bit_depth = 8;
int color_type = (inSurface->Format()&pfHasAlpha) ?
PNG_COLOR_TYPE_RGB_ALPHA :
PNG_COLOR_TYPE_RGB;
png_set_IHDR(png_ptr, info_ptr, w, h,
bit_depth, color_type, PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
png_write_info(png_ptr, info_ptr);
bool do_alpha = color_type==PNG_COLOR_TYPE_RGBA;
{
QuickVec<uint8> row_data(w*4);
png_bytep row = &row_data[0];
for(int y=0;y<h;y++)
{
uint8 *buf = &row_data[0];
const uint8 *src = (const uint8 *)inSurface->Row(y);
for(int x=0;x<w;x++)
{
buf[0] = src[2];
buf[1] = src[1];
buf[2] = src[0];
src+=3;
buf+=3;
if (do_alpha)
*buf++ = *src;
src++;
}
png_write_rows(png_ptr, &row, 1);
}
}
png_write_end(png_ptr, NULL);
*outBytes = ByteArray(out_buffer);
return true;*/
}
}