[Prev][Next][Index][Thread]
Re: A85: Have you ever seen this?
Hi!
At 21:47 11.3.1998 -0500, you wrote:
>
>"This routine replaces FIND_PIXEL and was written by Jim Kuzma. It is
>functionally and operationally compatible with FIND_PIXEL; the only
>difference is that HL is returned with the "physical" address instead of
>the offset. BC and DE are preserved. Jim Kuzma took a look at the
>FIND_PIXEL routine in the ROM and can say that this is better optimized
>for plotting. It automatically handles plotting."
>
>You can contact Jim Kuzma at 104165.456@compuserve.com
>
>The function is called plotxy
>
Personally I think it's better to optimize & integrate pixel plotting
there where you use it, so you can take advantage of arising special
cases (for example when you "scan" whole screen while drawing a some
function or fractal, you don't need to multiply by 16 and do other
housekeeping at all, just shift mask (and increment pointer after every
eighth pixel)). Find_pixel just can't be fast on ti-85, because of
ancient processor. If you want to make this general routine as fast as
possible you'd need lots of RAM for lookup buffers... maybe it's
possible to do this temporarily?
Of course this won't work for higher level languages...
/jani