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Re: A2 HTML viewer

mdj wrote:

Michael J. Mahon wrote:



And there were some programs that used HGR page flipping to produce
the "vertically interlaced" equivalent of DHR before there was DHR.



I've never seen a program do this. Combined with DHR you can get a
theoretical 560x384 interlaced display, however, you'll not have much
RAM left to do anything interesting on it ;)


True, and the real reason that a machine with 64KB addressing doesn't
support a higher-resolution display mode.  (People should appreciate
that Woz's color HGR design wasn't just a "hack"--it was a breakthrough
that made "pretty good" color graphics affordable on personal computers.)

Of course, there is the very real problem of viewing an interlaced
display with fine detail--the details flicker and crawl.

If the picture displayed on an interlaced monitor has vertical details
that are never sharper than about a line and a half, and it is viewed
from across the room, the results are excellent.

If there are fine vertical details only one line wide, then the
flicker of those details will be obvious even across the room, and
intolerable if sitting close.  Of course, fonts and horizontal lines
are the obvious cases of fine vertical details.


Multiscribe (which became BeagleWrite) used DHR mono to produce a
pretty decent MacWrite clone, then there's PublishIt! and TeachText,
two totally amazing peices of sofware for their time.

One should bear in mind that programming DHR without a prewritten
library to help you out is tricky.


It certainly is.  But 560 pixels is a strong motivation!  ;-)

-michael

Parallel computing for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it is seriously underused."