diff -r 7dbdc862097c -r 82f1f1d819c0 project_files/HedgewarsMobile/Classes/CommodityFunctions.m --- a/project_files/HedgewarsMobile/Classes/CommodityFunctions.m Sat Nov 13 01:24:39 2010 +0100 +++ b/project_files/HedgewarsMobile/Classes/CommodityFunctions.m Sat Nov 13 03:25:40 2010 +0100 @@ -142,3 +142,47 @@ return theLabel; } + +// this routine checks for the PNG size without loading it in memory +// https://github.com/steipete/PSFramework/blob/master/PSFramework%20Version%200.3/PhotoshopFramework/PSMetaDataFunctions.m +CGSize PSPNGSizeFromMetaData (NSString *aFileName) { + // File Name to C String. + const char *fileName = [aFileName UTF8String]; + // source file + FILE *infile = fopen(fileName, "rb"); + if (infile == NULL) { + DLog(@"Can't open the file: %@", aFileName); + return CGSizeZero; + } + + // Bytes Buffer. + unsigned char buffer[30]; + // Grab Only First Bytes. + fread(buffer, 1, 30, infile); + // Close File. + fclose(infile); + + // PNG Signature. + unsigned char png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10}; + + // Compare File signature. + if ((int)(memcmp(&buffer[0], &png_signature[0], 8))) { + DLog(@"The file (%@) is not a PNG file", aFileName); + return CGSizeZero; + } + + // Calc Sizes. Isolate only four bytes of each size (width, height). + int width[4]; + int height[4]; + for (int d = 16; d < (16 + 4); d++) { + width[d-16] = buffer[d]; + height[d-16] = buffer[d+4]; + } + + // Convert bytes to Long (Integer) + long resultWidth = (width[0] << (int)24) | (width[1] << (int)16) | (width[2] << (int)8) | width[3]; + long resultHeight = (height[0] << (int)24) | (height[1] << (int)16) | (height[2] << (int)8) | height[3]; + + // Return Size. + return CGSizeMake(resultWidth,resultHeight); +}