From: Nate Eldredge <neldredge AT hmc DOT edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Are THESE two statements EQUAL?
Date: 29 Jun 2000 14:50:28 -0700
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To: djgpp AT delorie DOT com
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Sinan_Unur AT mail DOT com (A. Sinan Unur) writes:

> as for BITMAP and PALLETE, all one should care about is the API
> through which you access these structures (that is the whole point
> why you are provided with a BITMAP data type rather than an array of
> int.) further, BITMAP and PALLETE are logically separate concepts
> regardless of any affinity that might exist between their underlying
> implementations.

And in fact, there isn't any.

typedef struct BITMAP            /* a bitmap structure */
{
   int w, h;                     /* width and height in pixels */
   int clip;                     /* flag if clipping is turned on */
   int cl, cr, ct, cb;           /* clip left, right, top and bottom values */
   GFX_VTABLE *vtable;           /* drawing functions */
   void (*write_bank)();         /* write bank selector, see bank.s */
   void (*read_bank)();          /* read bank selector, see bank.s */
   void *dat;                    /* the memory we allocated for the bitmap */
   int bitmap_id;                /* for identifying sub-bitmaps */
   void *extra;                  /* points to a structure with more info */
   int line_ofs;                 /* line offset (for screen sub-bitmaps) */
   int seg;                      /* bitmap segment */
   unsigned char *line[0];       /* pointers to the start of each line */
} BITMAP;

vs.

typedef struct RGB
{
   unsigned char r, g, b;
   unsigned char filler;
} RGB;
typedef RGB PALLETE[PAL_SIZE];

No similarities whatever.

-- 

Nate Eldredge
neldredge AT hmc DOT edu