Good evening, and thanks again for your replies. I wanted to do some research before replying again, so I include here my interpretation of each of your ideas. I'll start with the ideas that Robert Coup kindly shared. I'd appreciate if you could tell me if I misunderstood something:
As I understand, based on the discussion thread 'Mapnik viewer and OSM rendering' ( http://www.mail-archive.com/[email protected]/msg00096.html), there is an experimental branch developed by Ben Moores in which wxpdfdoc ( http://wxcode.sourceforge.net/components/wxpdfdoc/, a c++ library for creating PDF documents) is used to render maps on PDF documents and many of the features mentioned below are already included. Ideas from Robert Coup: ----------------------------------- Port features from wxpdf (/branches/experimental-pdf/) to a Cairo-based PDF renderer, including: - Adding a border to the map to show coordinates: I interpret this as displaying a frame around the map that shows the longitude and latitude coordinates. The more the map is zoomed in, the more exact the coordinates will be. - Grids: I interpret this as displaying the longitude and latitude lines over the map. - Scale bars: Display the chart that shows the scale of the map graphically (http://en.wikipedia.org/wiki/Linear_scale). - Overlay images, including other PDFs: Does the 'overlay' concept have the same meaning as in Google Maps? According to Google Maps' documentation, an overlay is an object attached to a coordinate, like the markers used to point to places ( http://code.google.com/apis/maps/documentation/mapplets/overlays.html#Markers). If this is true, then this feature is about displaying these overlay images on the exact points indicated by the associated coordinates (considering that the units used for displaying on the screen and printing on a document are different, am I right?). I'm not sure if I understand the part 'including other PDFs', though. - Paper sizes/scale calculations: I read that images are displayed on paper based on DPI units, so some calculations are needed to scale the maps to fit different paper sizes. Tom Hughes mentions in the same thread that there are some issues that need to be considered when tranlating the units used by Mapnik and those of Cairo. - Map layers as PDF layers: According to what I read, the objects displayed on a PDF page can be organized in layers, which can be hidden. As a map is rendered in layers, whose order is defined by a Mapnik configuration file ( http://trac.mapnik.org/wiki/XMLConfigReference), a PDF layer may be mapped to a map layer. Hiding a PDF layer in a PDF viewer should cause the 'status' attribute of the corresponding map layer to be set to OFF, causing it not be rendered. Finally, I read that Tom Hughes wrote a Cairo-based renderer, but I would like to ask you if these features are already covered by it. I'll do some research before replying to Mr. Pavlenko's and Mr. Marquardt ideas. There's also an idea from Ben Moores about automatic legend generation; is it related to what you say about legends, Mr. Marquardt? Thanks, Carlos López 2010/3/20 Robert Coup <[email protected]> > Hi Carlos, > > 2010/3/21 Carlos Enrique López Garcés <[email protected]>: > > Good evening Mapnik community, > > I've been searching for information about the 'Better Print Support' > project > > idea and I was wondiering if anyone could tell me how to contact Tom > Carden. > > He submitted the project idea, so I thought it would be a good idea to > ask > > him about it. Any suggestions will be really appreciated. Thanks. > > It's also worth having a look at the code on the (abandoned) wxpdf > branch. See this post (and others by Ben) to have a look: > > http://www.mail-archive.com/[email protected]/msg00140.html > > it has/had some cool features which could be worth porting to a > Cairo-based PDF renderer. > * paper sizes/scale calculations > * grids/graticules > * overlay images, including other PDFs > * scale bars > * borders around the map, with coordinates > * outputting map layers as true PDF layers. This allows turning on & > off individual layers in a PDF viewer. > > The addition of SVG symbol support makes things more scalable too... > > Rob :) >
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