2D lines and smartlines for DTM

When I do the proposed contours for parking lots, I prefere to use lines for the proposed contours since the parking lots vary so much and for the many changes that will come. After I've created the proposed DTM is there anyway to make the parking lot an object in a model so that I can do the side slopes, ponds and roads by objects in the same model?

Greg

Hi again,

I see that explanation in the Help and the only assumption I can make is that the tool has changed since that Help was written. It's certainly not valid now.

If you'd like to send your data too me I'd happy to take a look at what you have and let you know where you stand (and what dialog settings will/will not work.

ZIP the DGN and send it to michael.gilham@bentley.com

HTHs

3. The interpolation mode is only valid for Feature Types: Breaks, Contours, and Break Voids. For contours within a 2D file, the associated elevation must be within the Con Z-range, more commonly known as "tagged." Elevations for spot elevations may be determined by textual value (if the origin of the text is the origin of the spot) or "tagged" elevations for other element types, i.e., zero length lines or cells.

 that's the full quote from...

Bentley GEOPAK Site V8i/command reference/DTM tools/Ditigal Terrain Modeling/DTM Tools/Extract Tools/Extraction of Graphic Elements...around the 3rd paragraph

Hi,

1) If the extract elements represent "contours" then you should set them as a contour feature.

2) Stroking: Depends on how many data points you have on your graphical elements. Typically, if the contour elements were digitized, they will have more vertices than you would ever need so you would not use stroking (and may even consider "filtering" the points once the DAT has been created to reduce the amount of data). If the data is b-splines or mostly curves/arcs, you may want to add "curve" stroking to densify the data along the cureved elements so the eventual triangulations closly follows the curves. Its a tough call to respond on without seeing the data you have.

3) Absolutely no idea :-)... I'd have to find the context of that line in the Help before I could explain that one.

4) Yes. The single value will be applied to all connected elements.

5) Every line needs text. It will not interpolate between them. No text; and the lines will be ignored.

6) Yes. You will need to set it to "text" and then set it to "content" (drop down option just below the types field). This tells to software to look for an element type of text and then to read the text content as the elevation to be applied.

7) This is true IF you set the "content" option. If you leave the option as Origin, in a 2D file you will get zero as the elevation (as zero is the Z value of the origin of any element in a 2D file).

8) Correct!

9) This is the only method... if the elements are 2D (as in your case) there is a certain amount of data required for any software to assign an elevation automatically. There are manual methods where you could pick elements and assign elevations on an "element by element" basis; but I'm reasonably confidenet you don't want to go down that path...

HTHs.

Hi Michael:

1. should the feature be set to contours?
2. should stroking be used?
3. the help menu states "for contours within a 2D file, the associated elevation must be within the Con Z-range"... what does this mean?
4. is only one text per string of connected lines required?
5. does every line need a text, or will it interpolate if say every other line has text?
6. under spots criteria does the types field need to be checked? and what does types mean? and should content be selected?
7. the help menu states for content - "the x,y coords are derived from the text origin"..."however the z value is not the z value within a 3D file, but the actual value of the text, whether a 2D or 3D file"
8. if extract is set to View 1, it seems the software only finds the elements visible on the screen and a fit view should be done before apply
9. is this the best method to use or is it better to assign z's to all the lines and use extraction?

thanks for your help!

greg