Creating polygon topology with text labels as data

[Anonymous]

I use only ESRI programs (ArcCad, Arcview 3.2 and ArcGIS 8.1) for GIS
analyses and have been using AutoCad 14 right up until the last minute in
order to keep using ESRI's ArcCad 14. But alas, the time has come to look
into other options, so I now have AutoDesk Map 5. I was successful in
creating polygon topology and can/probably will be satisfied with DXFing the
linework and text labels in the centers of polygons out so that I can DXFARC
them into ArcInfo coverages. (Exporting polygons as ArcInfo coverages does
not work; they are arcs with annotation. Nor could I get the attributes to
export in shapefiles.) BUT if I wanted to create a 'coverage' or topology
with object data linked or attached, how would I do that? I went through
the tutorial and then tried creating a very simple project with three closed
polygons, each with a text label inside. I created an object data table
with one attribute, then I generated links using that table and had no luck.
Finally, I cleaned and created the topology, relinked the object data and
then used MAPCREATECENTROIDS and that did something but I'm not sure what!
If I could just find someone who knows how ESRI programs work and how Map
works to explain the likenesses and differences and translate the
nomenclature into something I can understand, then I would perhaps consider
using Map to perform simple spatial analyses. As it stands now, I'll only
use it to clean and create closed polygons, after which I'll either create a
coverage from the DXF or I'll import the drawing as a GDB in ArcToolBox to
be used in ArcMap.

One more question: what is the file structure of the objects and data
linked to them? Are the linked tables/objects considered to be geodatabases
or do they have a names?

[Anonymous]

Hello Martie- I am in the same boat as you. We used Arccad and still do somewhat to perform polygon GIS calcs. Moving to Autodesk Map will pay off, but it takes some research and learning to get it going. It does not do what I want out of the box. You will probably find the same thing to be true. The first thing I would recommend is taking an Autodesk certified Map 5 class. It is expensive but it will get you started off right. I would personally talk to the instructor and ask questions about topologies. The instructor I had barely got through topologies...he really could not show us all of the features. Autodesk university probably has someone good to teach Map if you want to spring for that. You might look for books as I did, I never found a book that quenched my thirst on topologies. Having found one book on Map 4(Thomson Learning, Mark Oliver, "Using AutoCAD Map 2000") after an extensive search...it is a little better than the book you get in the Map class. If I had a good medium to pass this knowledge to you, I would. It has taken me a year to get to the point of being able to get Map to do what I want (not exactly), I think that shows that there is a need for a better book or class on Autodesk Map. I could probably teach classes on Map topologies, if I had time that is. I am going to make another post to try to answer some of your questions.

[Anonymous]

Creating a topology. 1. Get all of your labels placed inside each polygon(the insertion point has to be inside).
2. Use drawing cleanup, run it until the numbers read 0,0,0.
3. Use create topology command, use the layer of your text labels as centroids, the link objects is the layer(s) of your polygons.
4. Mark errors and highlight errors are the only boxes that should be checked.
5. Run the topology create. You will have some errors to fix. Fix errors, drawing cleanup until 0,0,0; the create topology again. You may have to repeat these last steps a couple times.
6. Use "create closed polylines command", choose copy object data from centroid to pline. As an ESRI product user, I'm sure you know the attribute data is stored on the line and not on a centroid.
7. Use the export command, choose the object data that you have copied to the pline, make sure you ONLY select the closed polylines.

Make another post if I have left something out, Martie. Or maybe someone else can add to this.

By the way, it looks like you have a good method between the dxf and GDB to make spatial calcs. Can you make a post on this thread about how you do this? Most people in this discussion group could probably benefit from this information. Thanks.

[Anonymous]

Thanks for your post on polygon topology, "pl"
-- when I export as either an ArcInfo cov or a shapefile, I can't get the
attributes to go with the polygons.  What's the trick to get the attributes
out?  I don't think I'm creating object data correctly; or else I'm not
linking it correctly.  Please advise further, IF it's possible to export
polygon topology with attributes attached.

As for your request that I post the steps
involved for the other two options, I don't have ArcInfo in front of me at the
moment, so some of the specific nomenclature may not be accurate, but here
goes ...

To create a polygon GDB with linked data, follow
these steps:

1. After drawing cleanup, create topology and
then create closed polylines.  Write block the closed polylines with text
attributes in their centers out to a separate drawing so that it's really
simple.  Text and polylines can be on the same layer.

2. In ArcCatalog, create a personal
GDB.

3. in ArcToolBox, choose import or
export CAD drawing to GDB, then point to the blue icon drawing so that you
can choose between arcs, polygons, points or anno.  Choose polygon and
point to the newly created personal GDB and then name the new feature data
class.

4. Repeat step 3, pointing this time to the
annotation layer and name that data class appropiately.

5. In ArcMap, point to these two new feature
data classes (polygon and anno) which you created from the CAD
drawing.

6. Right click on the polygon feature class in
the data frame to the left and choose Join/Link, then join the
annotation to the polygon attribute table and I believe that a new,
merged feature data class is created with attributes intact.  (I may
have this step documented inaccurately and will repost if necessary after I
check later.)

To create an ArcInfo coverage from a DXF file,
follow these steps:

1. Perform drawing cleanup until 0,0,0,
then create topology successfully just to make sure that no errors exist.
 DXFOUT the cleaned polylines with text attributes in their
centers using AutoCAD R13 DXF format and select only the polylines
and text labels (they can be on the same or different layers).

2. In ArcToolBox, import the DXF to coverage and choose the blue
DXF icon/file.  In the resulting dialog, choose "select layers" and
select the layers of the dxf/drawing on which the entities you choose resided
(this allows you to eliminate layer 0).  Default through the rest
of the dialogs and name the coverage in the end, then finish.

3. Clean the new coverage as a polygon cov, using an appropriate fuzzy
tolerance; if the default is too high, change it to 1 at the most.  (use
either ArcToolBox or ArcInfo command)

4. 'Describe' and 'labelerrors' (Arc commands) for the new cov to make sure
it's clean.  Then 'dropitem' all the dxf-layers except dxf-text and
rename the item dxf-text to a desired name.

style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">

"pl" <pml@johnsoneng.com>
wrote in message
href="news:f0aefb8.1@WebX.maYIadrTaRb">news:f0aefb8.1@WebX.maYIadrTaRb...

Creating
a topology. 1. Get all of your labels placed inside each polygon(the insertion
point has to be inside).
2. Use drawing cleanup, run it until the numbers
read 0,0,0.
3. Use create topology command, use the layer of your text
labels as centroids, the link objects is the layer(s) of your polygons.
4.
Mark errors and highlight errors are the only boxes that should be checked.

5. Run the topology create. You will have some errors to fix. Fix errors,
drawing cleanup until 0,0,0; the create topology again. You may have to repeat
these last steps a couple times.
6. Use "create closed polylines command",
choose copy object data from centroid to pline. As an ESRI product user, I'm
sure you know the attribute data is stored on the line and not on a centroid.

7. Use the export command, choose the object data that you have copied to
the pline, make sure you ONLY select the closed polylines.

Make another post if I have left something out, Martie. Or maybe someone
else can add to this.

By the way, it looks like you have a good method between the dxf and GDB to
make spatial calcs. Can you make a post on this thread about how you do this?
Most people in this discussion group could probably benefit from this
information. Thanks.

[Anonymous]

Sorry for the delayed response, Martie. The trick to gettin gyour object data out is to use either the generate links command to write text to an object data table on the polygon, or when you use the create closed polylines command, make sure you check the "copy object data from centroid to pline". The part about create closed polylines is assuming that you have a topology built.

I find that using the generate links command works the best. Autodesk's topologies are not intelligent and are not customizable. Of course, you can do this in ArcView easily. Just watch when you use the generate links comand: if you have polygons inside of polygons, the object data gets copied to the inside polygon and the outside one.

Oh yeah, and thanks for your previous response.