// image.h
//
// This is a substitute for SGIs <gl/image.h> which doesn't
// work under C++.
//

#ifndef __GL_IMAGE_H__
#define __GL_IMAGE_H__
/*
 *      Defines for image files . . . .
 *
 *                      Paul Haeberli - 1984
 *      Look in /usr/people/4Dgifts/iristools/imgtools for example code!
 *
 */

#include <stdio.h>

#ifdef __cplusplus
extern "C" {
#endif

#define IMAGIC  0732

/* colormap of images */
#define CM_NORMAL               0       /* file contains rows of values which 
                                         * are either RGB values (zsize == 3) 
                                         * or greyramp values (zsize == 1) */
#define CM_DITHERED             1
#define CM_SCREEN               2       /* file contains data which is a screen
                                         * image; getrow returns buffer which 
                                         * can be displayed directly with 
                                         * writepixels */
#define CM_COLORMAP             3       /* a colormap file */

#define TYPEMASK                0xff00
#define BPPMASK                 0x00ff
#define ITYPE_VERBATIM          0x0000
#define ITYPE_RLE               0x0100
#define ISRLE(type)             (((type) & 0xff00) == ITYPE_RLE)
#define ISVERBATIM(type)        (((type) & 0xff00) == ITYPE_VERBATIM)
#define BPP(type)               ((type) & BPPMASK)
#define RLE(bpp)                (ITYPE_RLE | (bpp))
#define VERBATIM(bpp)           (ITYPE_VERBATIM | (bpp))
#define IBUFSIZE(pixels)        ((pixels+(pixels>>6))<<2)
#define RLE_NOP                 0x00

#define ierror(p)               (((p)->flags&_IOERR)!=0)
#define ifileno(p)              ((p)->file)
#define getpix(p)               (--(p)->cnt>=0 ? *(p)->ptr++ : ifilbuf(p))
#define putpix(p,x)             (--(p)->cnt>=0 \
                                    ? ((int)(*(p)->ptr++=(unsigned)(x))) \
                                    : iflsbuf(p,(unsigned)(x)))

typedef struct {
    unsigned short      imagic;         /* stuff saved on disk . . */
    unsigned short      type;
    unsigned short      dim;
    unsigned short      xsize;
    unsigned short      ysize;
    unsigned short      zsize;
    unsigned long       min;
    unsigned long       max;
    unsigned long       wastebytes;     
    char                name[80];
    unsigned long       colormap;

    long                file;           /* stuff used in core only */
    unsigned short      flags;
    short               dorev;
    short               x;
    short               y;
    short               z;
    short               cnt;
    unsigned short      *ptr;
    unsigned short      *base;
    unsigned short      *tmpbuf;
    unsigned long       offset;
    unsigned long       rleend;         /* for rle images */
    unsigned long       *rowstart;      /* for rle images */
    long                *rowsize;       /* for rle images */
} IMAGE;

/*
 *  Found prototypes in man entry for rgb(4)...
 *  The other functions are probably there also...
 */
IMAGE *iopen (char *, char *, unsigned int, unsigned int,
        unsigned int, unsigned int, unsigned int);
int iclose (IMAGE *);
int putrow (IMAGE *, unsigned short *,
        unsigned int, unsigned int);
int getrow (IMAGE *image, unsigned short *buffer,
        unsigned int y, unsigned int z);


/*
IMAGE *iopen();
IMAGE *icreate();
unsigned short *ibufalloc();
*/

#define IMAGEDEF                /* for backwards compatibility */

/*
 *  End extern "C"...
 */
#ifdef __cplusplus
}
#endif

#endif  /* !__GL_IMAGE_H__ */