[OSM-dev] Re: New renderer... move to Ruby/rmagick?

[Nick Whitelegg]

Hello Mikel (and all),

>> After that I would like to attempt to tackle two of the issues with the
>> renderer at higher zoom levels -- round caps, and antialiasing, neither 
of
>> which are supported by PHP/GD.
>>
>> I am considering switching to Ruby/rmagick for the following reasons:

>There is an ImageMagick extension for PHP if that's an easier 
intermediate step.

That's the other thing I was considering though the recommended binding 
(MagickWand) is quite new and needs manual setup (no deb package). There 
are actually two, there's an old deprecated one (installed already on the 
dev server), but the recommended ImageMagick binding for PHP now is 
MagickWand. Steve - would like to have a play with it so if I send you the 
installation instructions (or a URL to them)?

>I don't think we know. My tests earlier this year were not comprehensive, 
but seemed to show a big >performance hit for Ruby doing
>iterative calculations; Perl seemed to perform much better, and C would 
be even better. Neutral benchmarks >back this up..

>http://shootout.alioth.debian.org/gp4/benchmark.php?test=all〈=ruby

>We should set up some tile drawing tests without the database dependency, 
to see clearly the efficiency here.

Ruby vs PHP vs C would seem appropriate. However if the database querying 
is always going to be the rate-determining step, it might be better to 
leave it in to evaluate whether it really matters what language the map is 
rendered in.

Nick