Breaking up shapefiles Re: [Xastir] ESRI shapefiles and dbfawk

[William McKeehan]

In my typical situation, I have 4 shapefiles loaded:
  State Outlines
  County Outlines
  Interstates
  Major Roads

All of these are nation wide, so the coverage is very large. My most common
range of viewing with these shapefiles has been 2048 down to 64.

Once I zoom in closer than that, I use downloaded Tiger Map shapefiles that
are seperated by county.

I did see an increase in the memory used - about an 8MB increase (from 20 to
28), but it was only temporary.

On Sun, December 19, 2004 12:22 pm, Tom Russo said:
> On Sun, Dec 19, 2004 at 11:20:02AM -0500, we recorded a bogon-computron
> collision of the <mckeehan at mckeehan.homeip.net> flavor, containing:
>> I have to totally agree with Curt on this one. On my Linux box, which only
>> has
>> 64MB Ram, this change has made a very significant performance gain in map
>> redraws!
>
> Really?!?  Terrific.  I was very concerned about the size of the data
> structures that stored the indices, and not sure how much of a speed-up
> would be realized.  For me (2.6GHz processor, 1.5GB RAM), it's about
> 50%.  I haven't done timing comparisons on my laptop (800MHz, 256MB), but
> it was noticeable.  Panning seems to be where the big win is.
>
> How many shapefile maps do you typically have loaded at a time?
>
> My modifications will only have any noticeable effect when you are zoomed
> in to a much smaller area than the shapefile covers.
>
> Those users whose typical use of xastir is to have a handful of very large
> shapefiles that cover areas much larger than the zoom levels they tend to
> stay at will see the greatest improvement with the least memory hogging.
>
>> On Sun, December 19, 2004 12:40 am, Curt Mills said:
>> > On Sat, 18 Dec 2004, James Ewen wrote:
>> >
>> > Have you seen what the experimental code does that Tom added to
>> > Xastir?  Man, after the initial read, it's FAST!
>>
>> --
>> William McKeehan
>> KI4HDU
>> Internet: mckeehan at mckeehan.homeip.net
>> http://mckeehan.homeip.net
>> _______________________________________________
>> Xastir mailing list
>> Xastir at xastir.org
>> https://lists.xastir.org/mailman/listinfo/xastir
>
> --
> Tom Russo    KM5VY     SAR502  DM64ux         http://www.swcp.com/~russo/
> Tijeras, NM  QRPL#1592 K2#398  SOC#236 AHTB#1 http://www.qsl.net/~km5vy/
>  "When life gives you lemons, find someone with a paper cut."
>
>


-- 
William McKeehan
KI4HDU
Internet: mckeehan at mckeehan.homeip.net
http://mckeehan.homeip.net