[mapguide-internals] Dynamic tile rendering proposal

[Kenneth Skovhede, GEOGRAF A/S]

The current tile mechanism is using static images to serve pre-built 
images as tiles.
For this reason, the tiles are only usefull with "base layers".

I have worked with OpenLayers, and it has a very nice tiling mechanism.
DM Solutions have built some tiling support into the MapGuide provider 
for OpenLayers.
This uses the static tiles, and the row/column index system in MapGuide.

Using the "original" OpenLayers tiling mechanism one can get a dynamic 
MapGuide image
to load as tiles, giving the illusion that the page loads faster (when 
it actually loads a bit slower).

The problem with this method is that MapGuide optimizes the rendered 
image for the given bounds.
This is especially true for calculating label positions and overlaps.
I would like to add a parameter for the "GETMAPIMAGE" call that accepts 
an "outer bounds" parameter.

With this parameter, MapGuide should render the extent given by the 
extent parameter, but use the outer
bounds for determining label placements and any other details that may 
have the same problems.

With this, it would be possible for MapGuide to serve tiles from 
MapGuide, without relying on a
static tilcache.


I would like to add this as an RFC, but would like feedback on the idea, 
as well as possible problems.

-- 
Regards, Kenneth Skovhede, GEOGRAF A/S