struct rgb_image {
  /* User portion */
    int xsize, ysize;                  /* fill these in before using*/
    unsigned char *rbu, *bbu, *gbu;    /* fill in these too */

  /* Private portion */
    int last_reg;                      /* leave all of the rest alone */
    short *ooxmap, *ooymap;
    UBYTE *CubeLookup;
    UBYTE Palette24[(3*256)+4];
    unsigned char reg_mem[256][3];
    unsigned char reg_memx[256][3];
    unsigned short *cspace;
    struct HamePort *HamePort;
    int u_r_here;

    long reserved0; /* Reserved for future use - must be set to zero */
    long reserved1;
    long reserved2;
    long reserved3;
  };