4 replies to this topic

[Dennis McClendon]

Can anyone offer advice on moving map linework prepared in Illustrator/FreeHand into GIS? I have some notes from Martin about the workflow, but I'm not clear how you would easily link the lines to an attribute table.

[Martin Gamache]

Denis,

Good question,

My method does not provide for a way to do this and I can't think of a way to do it except using a graphical method such as color coding your linework and that would be a very limited way to do it for some general attributes that are not unique to every object. You may be able to do it based on line length and join based on that in the GIS afterwards, again could be complicated and difficult. There may be a way to do it with object xml tags, I dont know enough about this but I think illustrator is adding some of this functionality for data driven stuff.

But assuming you have vector objects in a drawing app (FH or Illu) and that they have attributes attached to them, it assumes you were able to add the attributes with Mapublisher correct? So you should be able to export them that way as well.

Perhaps I'm not clear on how the attribute table exists prior to the export?

[Hans van der Maarel]

A MAPublisher export would be the best way. If there are already attributes attached to the lines, it's just a simple export (one layer, one feature type per export). If not, you can use Illustrator selection tools (same color, same width etc) and add attributes with MAPublisher through the Edit Map Column option.

[Martin Gamache]

I've been thinking some more about this (well procrastinating really since I should be studying for an exam)....


Assuming the MP route is not an option then it's possible a spatial join with other vector objects with the attributes would be possible, but it may need alot of editing. Lets say you have a nice dataset of streets for a midwestern city that you created in FH and manage to get into ARC somehow. You also have a bad dataset that is maybe derived from tiger that sort of lines up with it but not 100% and is visually bad looking, but it has attributes that can be joined to your database. It is possible to do a spatial join to at least pass on some identifying attributes (street name or object ID). You could then use this new attribute in your clean data to link to your table.
I've had to do this before and it can work especially if you maybe convert your reference tiger lines to centroids first, buffer them and then do the spatial join that way. For a large dataset of very dense street it could be difficult and very slow...as spatial joins tend to be.

If it had to be done manually for a very large datasest (i.e. Chicago) I would create the vectors as a shapefile and then I might think about sending it away to India to have it attributed. The cost might not be too bad for what ends up being a potentially very valuable dataset.

mg

[frax]

if it is data in classes, with not too many classes (let's say highways and non-highways) one could export them as different layers.