nanogui: Microwindows for Hercules
Subject:
RE: Microwindows for Hercules
From:
Greg Haerr ####@####.####
Date:
16 Jul 1999 17:24:04 -0000
Message-Id: <01BECF7D.2704CC00.greg@censoft.com>
: Hmm. A 8086 isn't quite a PC on which you want to loose performance. And
: that's exactly what you're doing here. PutPixel is a short routine and you
: loose way to much time if you don't inline it...
The place where nano-X and microwindows spend at *least* 95% of their
pixel-pushing code is in drawing horizontal lines. All the demos but one
*never* draw a diagonal line, the only case where bresenham is used. I had
completed test cases to prove this...
:
: > 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)
Greg
