nanogui: Microwindows for Hercules
Subject:
Re: Microwindows for Hercules
From:
Ben Pfaff ####@####.####
Date:
16 Jul 1999 21:47:30 -0000
Message-Id: <87908gjmlz.fsf@pfaffben.user.msu.edu>
Greg Haerr ####@####.#### writes:
:
: > In this way, people like you and me don't have to rewrite bresenham for every
: > card someone wants....
:
: You wouldn't have to rewrite it for every -CARD-, you would have to re-
: write it for every BIT-DEPTH. Which isn't that much work anyway.
:
A good idea, almost. The BOGL library performs this for the packed pixel
modes, but the VGA requires OUT instructions inbetween memory accesses,
so it can't run on a generalized bit-depth algorithm in planes mode. (The VGA
design has to be seen/studied to be believed, I've never seen such a complicated
piece of hardware for something kinda-conceptually simple)
Although it would still require special case code, I believe that a
line-drawing routine for VGA16 would be relatively simple, since each
pixel is the same color. It's been a couple months since I've written
any VGA16 code, but IIRC writing a number of pixels all in one color
can be done with a specialized write mode that makes it easier.
