On 8/8/06, Patrick McNamara <[EMAIL PROTECTED]> wrote:

Re: frame counter:  Yes, we should implement a frame counter in hardware.

If the nanocontroller is full featured enough, the blink logic can be
implemented in software, but the counter being in hardware certainly
simplifies some things.  Regardless or hardware or software, I would shy
away from using palette magic to do text mode blinking.   I think the
resource requirements in terms of scratch RAM for the palette as well as
the logic for working with them and keeping them up to date will not be
worth it.

This is why I was saying we'd need to use all 256 palette entries.
Every time the blink status would change, we would have to update 128
of the entries.  Not 16.  When painting the foreground color of a
character, you're actually using a color cell number that accounts for
the background color.  So fg=4 and bg=5 would use pixel 0x45, but the
cell would be painted to color 4 when "on" and 5 when "off".

Technically, you only need to use 8 cells for the pixels that are
background-only, and you only need 16 for the foreground-only cells.
But doing that sparsely might simplify the algorithm (or not).

One other point, on the suggestion of just blinking to black instead of
the foreground color, I would argue against it.  If we are going to
bother to put a VGA emulation mode in the card then it really needs to
behave properly (as people expect).  Slow is ok, but outputting
different from what is the expected norm will generate lots of "it's
broke" comments.  Unfortunately, it's the negative comments that get
posted and spread around.

I suppose.  We'll get the clueless people complaining that it's
broken, not understanding anything about how we did it.  We'll get the
intermediate people who understand that it's an emulation who complain
that we could just do a better emulation.  And then we'll get the
people who REALLY have a clue who praise us for not spending too much
time and energy on something that's used for 5 seconds during boot.
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