[Lazarus] FPC Parser

[Hans-Peter Diettrich]

Alexander Klenin wrote:
> This is yet another long-standing todo item.
>   
That was actually on the list?  And here I thought I was the only one 
using TAChart
in such perverse ways...
> [I should publish my todo list somewhere... maybe as feature requests
> on issue tracker?]
>   
That's as good a place as any, although in my experience publishing todo 
lists never
seems to help with obtaining those coveted "round-tuits."   :D
> (consider inverted logarithmic
> axis case, for example).
>   
You know, I found a way to generate a SIGFPE in the axis demo on the 
logarithm transform page...
First uncheck log scale, then zoom in on some empty space ((-0.5,200), 
(1.5,1.5)), for example,
and then check log scale again.  Poof!
> Still, I think I did it in r25912:25925.
> This is a complex code, so I please test *and* review it, if you can.
>   
You're not kidding--this was non-trivial.  I started reviewing the 
changes but there are many
areas of TAChart I'm not familiar with so it is slow-going.  I'll have a 
more thorough look tomorrow
after I am rested.

I did test the line demo and then test the algorithm in my application 
with my data set.  Huge
performance increase compared to the previous TLineSeries.  The 
difference between my single
user-defined series and 32 line series with axis transformations is now 
negligible.  I can move the vertical
lines and scroll the graph smoothly, so this is sound in principle. 

You've really covered a lot of ground this last week.  This is really 
amazing work!  I know you're not
really doing this for _me_, but I have to extend my appreciation and 
thank you.  You rock, man :)

I had to cull a lot of usage information from the mailing list archives, 
demo source, and asking you.  Is
there a place on the wiki where I could perhaps contribute some 
documentation for posterity?