Re: Double hires mode color artifacts

[Dirk Thierbach <dthierbach@usenet.arcornews.de>]

Andy McFadden <fadden@fadden.com> wrote:
> There's a //e technote that contained some basic info about the "sliding
> window".  

Is that TN #3, "Double High-Resolution Graphics"? I read that, but 
couldn't make much sense out of it. If there's really a sliding window
of only 4 bits width, then colors should change continously throughout 
3 bits between different colors. Is that what actually happens in
the hardware? I have never seen DHR in color, we had monochrome monitors
for our Apple //e's in school.

> When implementing DHR conversion for CiderPress I sat in front of
> my IIgs RGB monitor with a magnifier trying to discern a simple pattern,
> and eventually gave up, since each pixel is modified by the colors that
> come before and, in some cases, the colors that follow.  

So far, no surprise :-)

> I ended up shipping with 4 different modes and letting the user pick their
> favorite. :-)

Do you have any notes how you made these modes? Or do I have to read
program source?

- Dirk