BBS: Inland Empire Archive
Date: 12-22-92 (12:50)             Number: 329
From: CORIDON HENSHAW              Refer#: NONE
  To: SCOTT WUNSCH                  Recvd: NO  
Subj: Programming                    Conf: (2) Quik_Bas
Hello Scott!

In a msg of <20 Dec 92>, Scott Wunsch writes to Chansak Sam:

 SW> SUB VGAPal (Attr%, Red%, Green%, Blue%)
 SW>   PALETTE Attr%, (Red%) + (Green% * 256) + (Blue% * 65536)

Ugh, that's SLOW.  PALETTE takes forever, not to mention
all that integer math...  Use this:

DECLARE SUB ReadPalette (Attr%, Red%, Green%, Blue%)
DECLARE SUB SetPalette (Attr%, Red%, Green%, Blue%)


SUB ReadPalette (Attr%, Red%, Green%, Blue%)
OUT &H3C7, Att%
Red% = INP(&H3C9)
Green% = INP(&H3C9)
Blue% = INP(&H3C9)

SUB SetPalette (Attr%, Red%, Green%, Blue%)
OUT &H3C7, Attr%
OUT &H3C8, Attr%
OUT &H3C9, Red%
OUT &H3C9, Green%
OUT &H3C9, Blue%

ReadPalette is for reading the color values of a attribute,
and SetPalette sets them.  All using direct access to the
VGA controller, so they are very fast. If I wanted to, I
could re-code them in ASM for more speed, but I don't quite
need them THAT fast ;)

Coridon Henshaw

Sirrus| /
    / |Software

...Gotta run, the cat's caught in the printer.

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