My TGA-loading function isn't working

[joeprogrammer]

When I try the following function, it does read the file, but first, the image type code doesn't come through correctly, the height and width are all funny, and when I go on websites that show how to load these files, they seem to match what I'm doing.

Does anybody know the problem? Help would be greatly appreciated.

// structure for loading TGA bitmaps
typedef struct
{
 
   int imageWidth;
   int imageHeight;
   unsigned int imageTypeCode;
   unsigned int bitCount;
   unsigned char* imageData;
} STGA;

// the TGA bitmap loader
bool loadTGA(char *filename, STGA tgaFile)
{
   FILE *file;
   unsigned char		badChar;
   short int		badInt;
   long		  	imageSize;
   int			colorMode;
  
   file = fopen(filename, "rb");
 
   if (!file)
      return false;
 
   fread(&badChar, sizeof(unsigned char), 1, file);
   fread(&badChar, sizeof(unsigned char), 1, file);
 
   fread(&tgaFile.imageTypeCode, sizeof(unsigned char), 1, file);
 
   //image type either 2 (color) or 3 (greyscale)
/*   if ((tgaFile.imageTypeCode != 2) && (tgaFile.imageTypeCode != 3))
   {
      fclose(file);
      return false;
   } */
 
   //13 bytes of useless data
   fread(&badInt, sizeof(short int), 1, file);
   fread(&badInt, sizeof(short int), 1, file);
   fread(&badChar, sizeof(unsigned char), 1, file);
   fread(&badInt, sizeof(short int), 1, file);
   fread(&badInt, sizeof(short int), 1, file);
   
   int imagewidth  = 0;
   int imageheight = 0;
 
   //image dimensions
   fread(&tgaFile.imageWidth, sizeof(short int), 1, file);
   fread(&tgaFile.imageHeight, sizeof(short int), 1, file);
   
   if (tgaFile.imageWidth != 256)
   printf("%a x %b\n", imagewidth, imageheight);
   
   //image bit depth
   fread(&tgaFile.bitCount, sizeof(unsigned char), 1, file);
   
   // print the depth count
//   printf("%a\n", tgaFile.bitCount);
 
   //1 byte of garbage data
   fread(&badChar, sizeof(unsigned char), 1, file);
 
   //colorMode -> 3 = BGR, 4 = BGRA 
   colorMode = tgaFile.bitCount / 8;
   imageSize = tgaFile.imageWidth * tgaFile.imageHeight * colorMode;
 
   //allocate memory for image data
   tgaFile.imageData = (unsigned char*) malloc (imageSize);
 
   //read in image data
   fread(tgaFile.imageData, sizeof(unsigned char), imageSize, file);
   
   int i;	// looping variable
 
   //change BGR to RGB (especially for OpenGL later on)
   for (i = 0; i < imageSize; i += colorMode)
   {
      //swap blue and red colour value 
      tgaFile.imageData[i] ^= tgaFile.imageData[i+2] ^=
        tgaFile.imageData[i] ^= tgaFile.imageData[i+2];
   }
 
   //close file
   fclose(file);
 
   return true;
}

[Salem]

1. Which OS/Compiler are you using

2. Which processor are you on - some of your reads will assume a particular endian-ess, and if your machine is different, then all your results will be wrong.

3. bool loadTGA(char *filename, STGA tgaFile)
If you're expecting the caller to get a modified copy of tgaFile, then you're out of luck.
Pass a pointer to the struct you want to modify, and update accordingly.

4. int i; // looping variable
Now you're writing C++ or C99 code.

5. //13 bytes of useless data
This comment makes no sense. There's no way the next 5 lines add up to 13 bytes.

[joeprogrammer]

I'm using a PPC Mac with XCode 2.2.

There is no way the next 5 lines add up to 13 [bytes].

I know, I couldn't figure that out either. I didn't actually write it, so don't blame me

I got it working but had to use different code.