Phil, I appreciate your problems Phil. The mapping functions are a bit of a half way house. Plplot doesn't (and I think shouldn't) provide full mapping tools. That's a different job. Get a GIS package if that is what you need. On the other hand, basic outline maps are very useful for scientific applications. You can do all this yourself with the generic API, but the mapping functions have some useful additional functionality in terms of projections / transforms etc.
As a non-US resident I've always been slightly irked that we only have global and US maps. For this reason (as well as for getting better resolution maps) it would also be good to allow users to easily add their own map data. Currently the format is undocumented so any change in format would be best implemented before we write the documentation and make it a public API! I would also think carefully about data format. Better resolution would be beneficial as you say. Might also be worth considering some standard format to make obtaining new maps easier. Of course one might argue that high resolution only really matters when you are looking at a small area zoomed in, at which point many of the benefits of the mapping functions in terms of projections / transformations don't really matter so much anyway as it is close to being a flat cartesian surface. Just my random thoughts. Andrew On Thu, Sep 13, 2012 at 02:31:27PM -0700, phil rosenberg wrote: > Hi again > I've just been through the source code to work out the file format. It > actually turned out to be rather simple - just a series of segments made up > of?2 byte numbers. Each starts with the number of points in the segment > followed by the lons then the lats for that segment. I've generated high res > binary files based on the coastline files from the ascii CIA files. If anyone > else would like the files then let me know. > Andrew - I think that although the data may have come from the CIA files, I > don't think plPlot uses the original format. The ascii files have a much > higher resolution than the two byte plPlot files?which results in some rather > unpleasant aliasing. I've put an example at > http://homepages.see.leeds.ac.uk/~earpros/plplottest/trackplot.png showing > the SE of the UK.?It is still much better than the previous results, but > maybe if the devs would consider allowing a 3 or 4 byte per point format the > results would be much improved. > Phil > > > > ________________________________ > From: phil rosenberg <philip_rosenb...@yahoo.com> > To: Andrew Roach <aroach....@yahoo.com> > Sent: Thursday, 13 September 2012, 16:04 > Subject: Re: [Plplot-devel] map resolution > > > Unfortunately after a significant amount of searching i've only been able to > find ascii versions of the CIA maps (which were on the page you suggested > Andrew). The maps with plPlot are binary so these don't work. > ? > If anyone has copies of more detailed maps then I'd appreciate it if you'd > let me know. At the moment I'm going to have to read in and plot the ascii > maps as a line plot, but I won't end up with the useful features of the > plmaps routine. > ? > Cheers > ? > Phil > > > ________________________________ > From: Andrew Roach <aroach....@yahoo.com> > To: phil rosenberg <philip_rosenb...@yahoo.com> > Sent: Thursday, 13 September 2012, 12:13 > Subject: Re: [Plplot-devel] map resolution > > At 03:53 AM 13/09/2012 -0700, you wrote: > > > Hi all > > I was just wondering what the format of the plPlot map files is? The maps > > included in plPlot are rather low resolution so wondered if it was possible > > for me to download more detailed ones form somewhere? > > > > Phil > > It was the CIA World DataBank map format. Many years ago I did use higher res > versions for something or other - they are out there if you look. > http://www.evl.uic.edu/pape/data/WDB/ might be some from what I can see. > > -Andrew > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Plplot-devel mailing list > Plplot-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/plplot-devel ------------------------------------------------------------------------------ Got visibility? Most devs has no idea what their production app looks like. Find out how fast your code is with AppDynamics Lite. http://ad.doubleclick.net/clk;262219671;13503038;y? http://info.appdynamics.com/FreeJavaPerformanceDownload.html _______________________________________________ Plplot-devel mailing list Plplot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/plplot-devel
