As my previous thread, Civil 3D can be helped to create thematic map, in which you can see the FDO benefit, it's easy to import various proprietary GIS formats. At this time I would like to try how to handle the point data (e.g. Tree survey) by using the map function. The Tree survey is designed to record those trees which merit protection and to identify those areas. Normally it uses point geometry to record the location.
The general procedure is:
Create ODBC data source linked in Windows -> Connect to ODBC in C3D -> Generate the points -> Create new theme
Step 1 - Datasource
This is the general excel table.
Step 2 - Create ODBC data source linked
I select "Driver do Microsoft Excel (*.xls)" driver to create the new ODBC connection. The excel file is store the raw data which doesn't assign any primary key. TreeSurvey was assigned the name of ODBC connection.
Step 3 - Add ODBC Connection and select Data Source Name (e.g. TreeSurvey)
In Civil 3D, click Add data button in the Display manager and select TreeSurvey as the ODBC connection name. Click Connect.
Step 4 - User Name & Password
Because I do not assign any password for ODBC connection, just click Login in the User Name & Password window.
Step 5 - After to click Login button, the table will be shown up in the schema column. Now you need to design the X, Y & Z and the coordinate system.
OK. The data was successfully imported to Civil 3D and the points are in 3 dimension.
Now you can generate the thematic theme according the information of the ODBC database.
What is the record sheet normally look like?
The record sheet to accompany the map normally should note the information:
- Reference Number
- Class (Single tree-T, group-G, etc.)
- Tree species
- Age (Semi-mature-S, Mature-M, etc.)
- Condition (Good-A, Fair-B, Poor-C, Dead-D)
- Landscape value (Trees provideing shelter, screen to houses, Recreation, Wildlife habitats, Filtering noise and dust in town, etc.)
- Photo ID
As below the color was represented the tree height; if the tree is tall, the color will be dark. It is easy to understand & visualize. Furthermore the table can be linked up with another sources to generate further information that it isn't easy to provide as before.
Finally the point theme can be exported to another geospatial software for doing interoperability. Those points can be also stored into GIS database, so the appearance would be changed according the database update.
I found the white paper is titled Best Practices for Working with Large Data Sets, it shows you a hint how to handle large data (e.g. LIDAR) In the Controlling Surface Data Resolution chapter, it also mention the map function in Civil 3D. This is a very good reference.
