tga.h

#ifndef __TGA_H__
#define __TGA_H__
/*=============================================================================   
     Module  : tga.h
     Purpose : Define routines to read and write targa files.
     Author  : Doug Ehlenberger, CNIC Mt. Sinai School of Medicine
               
==============================================================================*/
#include <stdlib.h>
#include <stdio.h>

#ifdef __cplusplus
extern "C"{
#endif

/* Data types. */

typedef unsigned char  TargaByte;
typedef short          TargaShort;
typedef int            TargaLong;


/* NOTE: Must set packing alignment! */

#pragma pack( push, 1 )

typedef struct tagTARGAFILEHEADER
   {
   TargaByte   idLength;           /* Length of image ID field. */
   TargaByte   colorMapType;       
   TargaByte   imageType;

   /* Color map specification. */

   TargaShort  colorMapFirstEntry; /* Index of first colop map entry. */
   TargaShort  colorMapLength;     
   TargaByte   colorMapEntrySize;  /* Bit per color map entry. */

   /* Image specification. */

   TargaShort  imageOriginX;
   TargaShort  imageOriginY;
   TargaShort  imageWidth;
   TargaShort  imageHeight;
   TargaByte   imageBitsPerPixel;
   TargaByte   imageDescriptor;
   }
   TARGAFILEHEADER;

#pragma pack( pop ) 


/* Values for "colorMapType" */

#define TARGA_NO_COLOR_MAP  0
#define TARGA_COLOR_MAP     1 


/* Values for "imageType" */

#define TARGA_NO_DATA                        0
#define TARGA_UNCOMPRESSED_COLOR_MAP         1
#define TARGA_UNCOMPRESSED_TRUE_COLOR        2
#define TARGA_UNCOMPRESSED_BLACK_AND_WHITE   3   /* i.e. grayscale */
#define TARGA_RLE_COLOR_MAP                  9
#define TARGA_RLE_TRUE_COLOR                10
#define TARGA_RLE_BLACK_AND_WHITE           11


/* Masks for the "imageDescriptor" 

    7 6 5 4 3 2 1 0
   -----------------
   |0|0| | | | | | |
   -----------------
   | A | B |   C   |

   A: not used
   B: image origin
   C; number of alpha bits */

#define TARGA_MASK_IMAGE_ORIGIN  0x30
#define TARGA_MASK_ALPHA_BITS    0x0F


/* Values for "imageDescriptor" image origin.
   i.e. screen destination of first pixel. 
   NOTE: Bit 4 is for left-to-right ordering and
   Bit 5 is for top-to-bottom ordering. */

#define TARGA_BOTTOM_LEFT   0x00
#define TARGA_BOTTOM_RIGHT  0x10
#define TARGA_TOP_LEFT      0x20
#define TARGA_TOP_RIGHT     0x30
                

/* Error codes. */

typedef enum
   {
   TARGA_NO_ERROR,
   TARGA_ERROR_OUT_OF_MEMORY,
   TARGA_ERROR_FILE_OPEN,
   TARGA_ERROR_FILE_READ,
   TARGA_ERROR_FILE_WRITE,
   TARGA_ERROR_COMPRESSION,
   TARGA_ERROR_UNSUPPORTED
   }
   TARGA_ERROR_CODE;


/* Currently supported pixel formats. */

typedef enum
   {
   TARGA_UNSUPPORTED,
   TARGA_8BIT_GRAYSCALE,
   TARGA_16BIT_GRAYSCALE,
   TARGA_24BIT_BGR,
   TARGA_32BIT_BGRA,
   TARGA_16BIT_BGR,
   TARGA_8BIT_INDEX_24BIT_BGR_TABLE,
   TARGA_8BIT_INDEX_32BIT_BGRA_TABLE,
   TARGA_8BIT_INDEX_16BIT_BGR_TABLE
   }
   TARGA_TYPE;


/* Main structure. */

typedef struct tagTARGAFILE
   {
   TARGAFILEHEADER   header;
   void             *colorMap;
   void             *image;
   }
   TARGAFILE;


/* Functions. */

TARGA_TYPE GetTargaType( TARGAFILEHEADER *header );

TARGA_ERROR_CODE ReadTarga( char *fileName, TARGAFILE *targa );
TARGA_ERROR_CODE WriteTarga( char *fileName, TARGAFILE *targa );


#ifdef __cplusplus
}
#endif

#endif/* __TGA_H__ */

---