[Mapserver-dev] Antialiasing State of Affairs

[Titus von der Malsburg]

On Thu, Sep 09, 2004 at 04:03:11PM -0500, Steve Lime wrote:
> 1a) Report them as bugs! The cartoline stuff should be pretty good and
> the developer is
> still around. I can try to fix things if he can't/won't.

I filed it as bug 860.

> 1b) GD only supports single pixel lines (last time I looked). I'd need
> to seem samples of "odd" to comment further. Cartolines are the way to
> get wide, antialiased lines.

The "ood" look was due to my misuse of the LINEJOIN parameter.  When I
set its value to round the lines looked ok, even if not really
antialiased.

See http://www.cl.uni-heidelberg.de/~malsburg/temp/catroline.png

> 2 a/b) Not really. I'd prefer a more unified model. The code was
> developed at seperate times with
> 2 or 3 authors. Cartolines and the ttf lines were special cases of a
> normal line. Ideally they will
> become unified. I spoke briefly with the cartoline developer at MUM2
> about the possibility.
>
> 3) Tough to say, but it's not trivial. There are a couple of major
> tasks:
>
>   - cartoline cleanup
>   - generic symbol rotation for vector symbol descriptions and images.
>   - logic to know when cartolines are a more appropriate approach to a
> brush.

I'm not sure if we are talking about the same thing.  What I meant was a
unified concept in implementation not only from the users perspective.

> My guess would be several weeks of development. Futhermore we may want
> to look at another
> rendering engine, OpenGL has been suggested, as opposed to GD.
> Something to think about.

Cairo (http://cairographics.org/) seems to be very popular and has a lot
of nice properties.  It has support for output in the formats:
Postscript, OpenGL, image buffers.  Work on SVG- and PDF-output is in
progress.

Since it would free Mapserver from the need to handle these cases
seperately, wouldn't it make its code slimmer and easier to maintain?

(I'm not an expert for these thing, so please apologise if this is
nonsense.)

	Titus