[mapserver-dev] plugin renderer support status update

[thomas bonfort]

hi guys, merry christmas to you

I've been spending some of my holiday time on implementing "plugin"
rendering for mapserver vector handling, and applied this on adding a
cairo backend.

some really pre-alpha code has been checked into the "graphics" sandbox:
 * support for cairo output driver (currently png, svg and pdf)
 * "plugin" renderer support (currently only cairo uses it)
 * text layout is managed by pango for the cairo rendering (should
open up a nice couple of things, notably for non-ascii text support)

I still have quite a lot of work to do to support the full mapfile
possibilities (follow text, marker/shield/filling symbols, transparent
layers, the list goes on...)

some samples here:
 * reference agg output: http://terriscope.fr/ms_tmp/osmagg.png
 * cairo png: http://terriscope.fr/ms_tmp/osmcairo.png
 * cairo svg: http://terriscope.fr/ms_tmp/svgfile.svg
 * cairo pdf: http://terriscope.fr/ms_tmp/pdffile.pdf

what's really cool is that the core cairo rendering code weighs in at
under 300 lines, thanks to the plugin approach.

cheers,

thomas