Sebastian Schmitz wrote:
Hi,
we currently encounter a problem related to handling styles that are
directly attached to objects. Styles are contained within the objects'
attribute table (eg font, size, symbol....).
Mapserver already provides some mechanisms for that related to Labels.
At the layer level eg LABELANGLEITEM or LABELITEM can be specified
through a column in the attribute table. However, to meet our needs this
would have to be extended to fonts used for labelling and to the some
parameters within the STYLE object (). Two questions on that:
- Could someone supply a rough estimate of cost?
- How much would performance suffer when attaching styles at feature
level rather than at the class level?
Sebastian,
FYI in 5.0 has a new mechanism to bind some of the style and label
properties to shape attributes, there is some info about this in the 5.0
migration guide:
http://mapserver.gis.umn.edu/development/release_plans/mapserver_5_0/migration_guide_410_50/
The following properties can accept bindings:
* Style: angle, color, outlinecolor, size, symbol
* Label: angle, color, outlinecolor, size, font, priority
With respect to performance, there is definitely a cost associated with
that, but I am not aware of any benchmarks comparing static values to
attribute binding. If you do some performance comparisons then please
share with the list.
Daniel
--
Daniel Morissette
http://www.mapgears.com/
