engine/src/Utils/PngHelper.cpp
2013-01-19 20:02:34 +00:00

133 lines
3.0 KiB
C++

#include "include/Utils/PngHelper.h"
#include "include/Utils/Utils.h"
namespace SE
{
#ifdef TARGET_ANDROID
typedef PNG_CONST png_byte FAR * png_const_bytep;
#endif
struct TPngReadStruct
{
const boost::shared_array<char>& FileArr;
cardinal FileSize;
int CurrentPointer;
TPngReadStruct(const boost::shared_array<char>& fileArr, cardinal fileSize)
: FileArr(fileArr)
, FileSize(fileSize)
, CurrentPointer(8)
{
}
};
void user_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
{
png_voidp a = png_get_io_ptr(png_ptr);
TPngReadStruct* pngReadStruct = reinterpret_cast<TPngReadStruct*>(a);
if (pngReadStruct->CurrentPointer + length >= pngReadStruct->FileSize)
{
throw ErrorToLog("PNG pointer gone too far!");
}
for (cardinal i = 0; i < length; i++)
{
data[i] = pngReadStruct->FileArr[pngReadStruct->CurrentPointer + i];
}
pngReadStruct->CurrentPointer += length;
}
TPngDataStruct read_png_file(const boost::shared_array<char>& fileArr, cardinal fileSize)
{
TPngDataStruct result;
TPngReadStruct readStruct(fileArr, fileSize);
char header[8]; // 8 is the maximum size that can be checked
for (cardinal i=0; i<8; i++)
{
header[i] = fileArr[i];
}
if (png_sig_cmp(reinterpret_cast<png_bytep>(header), 0, 8))
{
throw ErrorToLog("Incorrect PNG file (1)!");
}
/* initialize stuff */
result.PngPtr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!result.PngPtr)
{
throw ErrorToLog("Incorrect PNG file (2)!");
}
result.InfoPtr = png_create_info_struct(result.PngPtr);
if (!result.InfoPtr)
{
throw ErrorToLog("Incorrect PNG file (3)!");
}
if (setjmp(png_jmpbuf(result.PngPtr)))
{
throw ErrorToLog("Incorrect PNG file (4)!");
}
png_set_read_fn(result.PngPtr, (png_voidp)&readStruct, user_read_data);
png_set_sig_bytes(result.PngPtr, 8);
png_read_info(result.PngPtr, result.InfoPtr);
result.Width = png_get_image_width(result.PngPtr, result.InfoPtr);
result.Height = png_get_image_height(result.PngPtr, result.InfoPtr);
result.ColorType = png_get_color_type(result.PngPtr, result.InfoPtr);
result.BitDepth = png_get_bit_depth(result.PngPtr, result.InfoPtr);
if (result.BitDepth != 8)
{
throw ErrorToLog("Incorrect bit depth in png file!");
}
if (result.ColorType != PNG_COLOR_TYPE_RGB && result.ColorType != PNG_COLOR_TYPE_RGBA)
{
throw ErrorToLog("Incorrect color type in png file!");
}
result.NumberOfPasses = png_set_interlace_handling(result.PngPtr);
png_read_update_info(result.PngPtr, result.InfoPtr);
if (setjmp(png_jmpbuf(result.PngPtr)))
{
throw ErrorToLog("Incorrect PNG file (5)!");
}
result.RowPointers = (png_bytep*) malloc(sizeof(png_bytep) * result.Height);
for (int y=0; y<result.Height; y++)
result.RowPointers[y] = (png_byte*) malloc(png_get_rowbytes(result.PngPtr, result.InfoPtr));
png_read_image(result.PngPtr, result.RowPointers);
return result;
}
} //namespace SE