bool CCImage::_initWithPngData(void * pData, int nDatalen)
{
bool bRet = false;
png_byte header[8] = {0};
png_structp png_ptr = 0;
png_infop info_ptr = 0;
unsigned char * pImateData = 0;
do
{
// png header len is 8 bytes
CC_BREAK_IF(nDatalen < 8);
// check the data is png or not
memcpy(header, pData, 8);
CC_BREAK_IF(png_sig_cmp(header, 0, 8));
// init png_struct
png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
CC_BREAK_IF(! png_ptr);
// init png_info
info_ptr = png_create_info_struct(png_ptr);
CC_BREAK_IF(!info_ptr);
#if (CC_TARGET_PLATFORM != CC_PLATFORM_BADA)
CC_BREAK_IF(setjmp(png_jmpbuf(png_ptr)));
#endif
// set the read call back function
tImageSource imageSource;
imageSource.data = (unsigned char*)pData;
imageSource.size = nDatalen;
imageSource.offset = 0;
png_set_read_fn(png_ptr, &imageSource, pngReadCallback);
// read png
// PNG_TRANSFORM_EXPAND: perform set_expand()
// PNG_TRANSFORM_PACKING: expand 1, 2 and 4-bit samples to bytes
// PNG_TRANSFORM_STRIP_16: strip 16-bit samples to 8 bits
// PNG_TRANSFORM_GRAY_TO_RGB: expand grayscale samples to RGB (or GA to RGBA)
png_read_png(png_ptr, info_ptr, PNG_TRANSFORM_EXPAND | PNG_TRANSFORM_PACKING
| PNG_TRANSFORM_STRIP_16 | PNG_TRANSFORM_GRAY_TO_RGB, 0);
int color_type = 0;
png_uint_32 nWidth = 0;
png_uint_32 nHeight = 0;
int nBitsPerComponent = 0;
png_get_IHDR(png_ptr, info_ptr, &nWidth, &nHeight, &nBitsPerComponent, &color_type, 0, 0, 0);
// init image info
m_bPreMulti = true;
m_bHasAlpha = ( info_ptr->color_type & PNG_COLOR_MASK_ALPHA ) ? true : false;
// allocate memory and read data
int bytesPerComponent = 3;
if (m_bHasAlpha)
{
bytesPerComponent = 4;
}
pImateData = new unsigned char[nHeight * nWidth * bytesPerComponent];
CC_BREAK_IF(! pImateData);
png_bytep * rowPointers = png_get_rows(png_ptr, info_ptr);
// copy data to image info
int bytesPerRow = nWidth * bytesPerComponent;
if(m_bHasAlpha)
{
unsigned int *tmp = (unsigned int *)pImateData;
for(unsigned int i = 0; i < nHeight; i++)
{
for(int j = 0; j < bytesPerRow; j += 4)
{
*tmp++ = CC_RGB_PREMULTIPLY_APLHA( rowPointers[i][j], rowPointers[i][j + 1],
rowPointers[i][j + 2], rowPointers[i][j + 3] );
}
}
}
else
{
for (unsigned int j = 0; j < nHeight; ++j)
{
memcpy(pImateData + j * bytesPerRow, rowPointers[j], bytesPerRow);
}
}
m_nBitsPerComponent = nBitsPerComponent;
m_nHeight = (short)nHeight;
m_nWidth = (short)nWidth;
m_pData = pImateData;
pImateData = 0;
bRet = true;
} while (0);
CC_SAFE_DELETE_ARRAY(pImateData);
if (png_ptr)
{
png_destroy_read_struct(&png_ptr, (info_ptr) ? &info_ptr : 0, 0);
}
return bRet;
}
void Image::createTexture(const void *input, unsigned int size)
{
const char *filename = m_src.c_str();
do{
const void *raws = input;
png_byte header[8];
memcpy(header, raws, 8);
// 读取图片头,判断是否PNG文件
if( png_sig_cmp(header, 0, 8) )
{
LOG("Not a png file : %s", filename);
break;
}
// 创建PNG读取结构
png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if( !png_ptr )
{
LOG("Unable to create png struct : %s", filename);
break;
}
// 创建PNG信息结构
png_infop info_ptr = png_create_info_struct(png_ptr);
if( !info_ptr )
{
png_destroy_read_struct(&png_ptr, (png_infopp) NULL, (png_infopp) NULL);
LOG("Unable to create png info : %s", filename);
break;
}
if( setjmp(png_jmpbuf(png_ptr)) )
{
LOG("Error during setjmp : %s", filename);
png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp) NULL);
break;
}
// 设置数据读取函数
void *inputCopy = (void *)input;
png_set_read_fn(png_ptr, &inputCopy, png_raw_read);
// 设置PNG数据宽度处理 RGB/RGBA 24/32bit
//png_read_png(png_ptr, info_ptr, PNG_TRANSFORM_EXPAND | PNG_TRANSFORM_PACKING
// | PNG_TRANSFORM_STRIP_16 | PNG_TRANSFORM_GRAY_TO_RGB, 0);
png_read_info(png_ptr, info_ptr);
// 读取图片信息
int bit_depth, color_type;
png_uint_32 twidth, theight;
png_get_IHDR(png_ptr, info_ptr, &twidth, &theight, &bit_depth, &color_type, NULL, NULL, NULL);
hasAlpha = ( color_type & PNG_COLOR_MASK_ALPHA ) ? true:false;
LOG("PNG width=%u height=%u bit_depth=%d alpha=%d", twidth, theight, bit_depth, hasAlpha);
// Update the png info struct.
//png_read_update_info(png_ptr, info_ptr);
int rowbytes = png_get_rowbytes(png_ptr, info_ptr);
LOG("PNG rowbytes:%d", rowbytes);
int bytes_per_component = hasAlpha ? 4:3;
width = twidth;
height = theight;
POTWidth = computePOT(width);
POTHeight = computePOT(height);
png_byte *image_data = new png_byte[POTWidth * POTHeight * bytes_per_component];
if( !image_data )
{
png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp) NULL);
LOG("Unable to allocate image_data while loading %s ", filename);
break;
}
// 创建并设置行指针
png_bytep *row_pointers = new png_bytep[theight];
if( !row_pointers )
{
png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp) NULL);
delete[] image_data;
LOG("Unable to allocate row_pointer while loading %s ", filename);
break;
}
for( int i = 0; i < theight; i++ )
{
row_pointers[i] = image_data + i * POTWidth * bytes_per_component;
}
png_read_image(png_ptr, row_pointers);
png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp) NULL);
delete[] row_pointers;
// 如果有alpha值,开始预乘
if( hasAlpha )
{
for( int i=0; i<theight; i++ )
{
for( int j=0; j<twidth; j++ )
{
unsigned char *pixel = (unsigned char *)(image_data + (i * POTWidth + j) * bytes_per_component);
*((unsigned int *)pixel) = CC_RGB_PREMULTIPLY_APLHA( pixel[0], pixel[1], pixel[2], pixel[3] );
}
}
}
setupTexture(image_data);
delete[] image_data;
JSCContext::getInstance()->callJSFunction(onload);
TRACE("load Texture finished:%s", m_src.c_str());
TRACE("texture %d", m_texture);
}while(false);
}
