Listing 1.  WAD File Structures
// Header structure.
typedef struct
{
	char	identification[4];
	long	numlumps;
	long	infotableofs;
} WADHEADER, *PWADHEADER;

// Directory structure.
typedef struct
{
		long 	filepos;
		long 	size;
		char 	name[8];
} LUMPS, *PLUMPS;

// Masked object (actors and sprites) structure.
typedef struct
{
		short origsize;			// the orig size of "grabbed" gfx
		short width; 				// bounding box size
		short height;
		short leftoffset;			// pixels to the left of origin
		short topoffset; 			// pixels above the origin
		short collumnofs[320];	// only [width] used, the [0] is
									// &collumnofs[width]
} PATCH, *PPATCH;

// Transparent object structure.
typedef struct
{
		short origsize;			// the orig size of "grabbed" gfx
		short width; 				// bounding box size
		short height;
		short leftoffset;			// pixels to the left of origin
		short topoffset;			// pixels above the origin
		short translevel;
		short collumnofs[320];	// only [width] used, the [0] is
									// &collumnofs[width]
} TRANSPATCH, *PTRANSPATCH;

// Structure used for floor and ceiling data.
typedef struct
{
		short	Width,Height;
		short	Orgx,Orgy;
} FLOORCEILING, *PFLOORCEILING;

Note: These structure examples are given in the Official ROTT Specifications file, ROTSP1, by Apogee Software.