cycle through polygons and create Boundaries - LDD4

Hi, I've used VBA a little, need help with some LDD4 and Civil commands. I
want to take all polygons (polylines) in a drawing and cycle through them to
perform the same tasks on each. The polygons are watershed basins and I
need to use each polygon as a boundary and from that boundary create a grid
of 3d polylines then create a pond from the resulting linework and finally
get a stage storage curve from this. I am using only one surface and
simply need to delete the old boundary create the new boundary. Is there
any access to Grading or Hydrology through VBA? Right now I have the
following code:

Sub Delete_first_Boundary()

Dim surf As AeccSurface
Dim bounds As AeccBoundaries
Dim Bound As AeccBoundary
Set surf = AeccApplication.ActiveProject.Surfaces.Item(0)
Set bounds = surf.Inputs.Boundaries
Set Bound = bounds.Item(0)

' Delete the old Boundary
bounds.Delete Bound.Id

' Add a new Boundary

Dim returnObj As AcadObject
Dim selection As Variant
Dim basePnt As Variant
On Error Resume Next

'this doesn't work - any ideas?
ThisDrawing.Utility.GetEntity returnObj, basePnt, "Select an object"
bounds.Add kBoundaryTypeOuter, False, returnObj, "NEW BOUNDARY"

End Sub

 

Craig,

The correct form of adding to the Land ActiveX Boundaries Collection is:

RetVal = object.Add(Type, bIsBreakLine, Coordinates[, Description])

Where, Coordinates are a variant (array of doubles); input-only; in Easting,
Northing, Elevation format.

You cannot simply add the selected polyline object, you have to identify or
filter the selected object as a LightweightPolyline, polyline, or
3dpolyline; extract the coordinates (coordinates property); and then pass
those coordinates to the bounds.add method. Note: the boundary coordinates
need to be 3D, even though the Z value is not really used in the boundary
application. If your selected object is a LightweightPolyline object, you
will have to convert its coordinates array of 2D points to an array of 3D
points with a zero or dummy Z value.

No, Land Grading Objects and hydrology data is NOT exposed through the API.

You have an pretty ambitious goal to code, good luck with it. There is a
autodesk.aec.land-desktop.customization NG that you may wish to peruse, and
post there for pertinent questions regarding the Land API.

sc

 

Hi Craig,

This sounds a highly ambitious project. Are you sure that you will use it
enough to recover the programming time ?

Bear in mind that once you have drawn the polyline you wish to use for a
boundary, you can set up a set of "Standard slopes etc." for a grading
object and attach a grading object defining a pond very quickly.

Or you can draw in contours of the model at a very close spacing and use the
contours to define your ponds.

I would suggest you do an analysis of what your requirements are and how
long it would take to do them with the standard tools, then how long you
would take with your proposed program. Multiply each by the expected number
of times you will do it Add on the program learning, programming time and
programming debugging times and decide where to go from there.

Other approaches which may warrant consideration are "stacking" menu
commands onto an Icon, or using "Sendcommand" to carry out the standard Land
Desktop, or Civil Design commands.

As an example of this I wrote a program which had a user interface with
buttons to call the 6 DTM editing commands in Land Desktop. On exit from
the program it opened the create contours dialog box, allowing the user to
edit and redraw contours all from one menu pick.

--


Laurie Comerford
CADApps
www.cadapps.com.au