topic Re: Analyzing surface elevations, lisp programmers? in AutoCAD Map 3D Developer Forum

Analyzing surface elevations, lisp programmers?

Yami72 — Thu, 29 Apr 2010 12:09:51 GMT

Hi,

Is there programmers who could do a (lisp) tool for analyzing surface elevations?

I need a tool that
- gives me a text file containing information of elevation of specified areas.
- Needed data is 2D-areas at spesific elevation ranges
- Data of several sequential analyzed areas should be placed in the same txt file and named by ordinal number (1, 2, 3,...)
- The ordinal number of the each analyzed area should be drawn to the picked point inside the area.
- A closed polyline should be drawn around the analyzed area (to later check if the area is the wanted one)
- Used elevation ranges could be read from a text file.

The text file should look something like this (forest01.txt):
forest01-1
range 123.20-123.29 m area 234 m2
range 123.30-123.39 m area 543 m2
range 123.40-123.49 m area 0 m2
Total area 777 m2

forest01-2
range 123.20-123.29 m area 0 m2
range 123.30-123.39 m area 123 m2
range 123.40-123.49 m area 235 m2
Total area 238 m2

etc.

Some definitions:
- The surface is a normal Autocad surface generated from lidar data (few millions ascii-points)
- Analyzed areas can be specified by lines, polylines or 2D polylines. Polylines can be open, closed and crossing each other, but they always form a closed area (which you can for example hatch by picking a point).
- Areas are typically small (less than 1 m2 to 1-5 hectares)

Using the program should be extremely simple because there can be hundreds of areas. Idea of the workflow:
Start lisp
Accept the range file by hitting enter
Give a name to the text file
Pick a point inside the first area
Pick a point insidethe second area
etc
End lisp

Is this doable?
How much it would take time (and money)?

I am using Autocad Civil 3D 2009-10-11

If you are interested, please see the attached file. I will post the elevation point file if needed.

Jami

Re: Analyzing surface elevations, lisp programmers?

Anonymous — Thu, 29 Apr 2010 12:30:19 GMT

Correction to your post, the surface is a Civil 3D TIN Surface not a
standard AutoCAD surface.

Why not use the tools already in C3D to get the info you need or the point
cloud tools in 2011?

--

Murph
http://map3d.wordpress.com/

"Jamiaho" wrote in message news:6382630@discussion.autodesk.com...
Hi,

Is there programmers who could do a (lisp) tool for analyzing surface
elevations?

I need a tool that
- gives me a text file containing information of elevation of specified
areas.
- Needed data is 2D-areas at spesific elevation ranges
- Data of several sequential analyzed areas should be placed in the same txt
file and named by ordinal number (1, 2, 3,...)
- The ordinal number of the each analyzed area should be drawn to the picked
point inside the area.
- A closed polyline should be drawn around the analyzed area (to later check
if the area is the wanted one)
- Used elevation ranges could be read from a text file.

The text file should look something like this (forest01.txt):
forest01-1
range 123.20-123.29 m area 234 m2
range 123.30-123.39 m area 543 m2
range 123.40-123.49 m area 0 m2
Total area 777 m2

forest01-2
range 123.20-123.29 m area 0 m2
range 123.30-123.39 m area 123 m2
range 123.40-123.49 m area 235 m2
Total area 238 m2

etc.

Some definitions:
- The surface is a normal Autocad surface generated from lidar data (few
millions ascii-points)
- Analyzed areas can be specified by lines, polylines or 2D polylines.
Polylines can be open, closed and crossing each other, but they always form
a closed area (which you can for example hatch by picking a point).
- Areas are typically small (less than 1 m2 to 1-5 hectares)

Using the program should be extremely simple because there can be hundreds
of areas. Idea of the workflow:
Start lisp
Accept the range file by hitting enter
Give a name to the text file
Pick a point inside the first area
Pick a point insidethe second area
etc
End lisp

Is this doable?
How much it would take time (and money)?

I am using Autocad Civil 3D 2009-10-11

If you are interested, please see the attached file. I will post the
elevation point file if needed.

Jami

Re: Analyzing surface elevations, lisp programmers?

Yami72 — Mon, 03 May 2010 07:15:55 GMT

Thank you for your answer Murph,

Yes, you are right, it is Civil 3D TIN surface I am talking about.

I don't know if it is possible to automate the process enough with the existing tools. I need exactly these things: results in a simple seperate text file as described before (for further calculations in excel), the polyline around the analyzed area and the ordinate number inside the area. These things and nothing else.

I tried to find a solution with the existing tools, but I could not find a satisfying solution. (I am not very experienced Autocad user... And 2011 is just installed, so I don't know much it's features)

I really need an extremely simple workflow, because there are hundreds of areas and one unnecessary and mouse click means hundreds of unnecessary mouse clicks. And I have many projects like this.

If there is an easy solution or a path to seek "the one mouse click on each area" solution with existing tools, I am willing to hear it

Jami

Re: Analyzing surface elevations, lisp programmers?

Yami72 — Mon, 03 May 2010 08:26:52 GMT

Of course, the best solution would be just giving the command that does everything automatically on specified surface with specified elevation ranges, without me clicking on every area. But this would be more difficult to code, or maybe easier? I am not a programmer either.

Re: Analyzing surface elevations, lisp programmers?

Anonymous — Mon, 03 May 2010 11:20:30 GMT

Map3D is very limited in working with Civil3D objects, you may want to ask
in the Civil 3D groups for assistance.

--

Murph
http://map3d.wordpress.com/

"Jamiaho" wrote in message news:6384458@discussion.autodesk.com...
Thank you for your answer Murph,

Yes, you are right, it is Civil 3D TIN surface I am talking about.

I don't know if it is possible to automate the process enough with the
existing tools. I need exactly these things: results in a simple seperate
text file as described before (for further calculations in excel), the
polyline around the analyzed area and the ordinate number inside the area.
These things and nothing else.

I tried to find a solution with the existing tools, but I could not find a
satisfying solution. (I am not very experienced Autocad user... And 2011 is
just installed, so I don't know much it's features)

I really need an extremely simple workflow, because there are hundreds of
areas and one unnecessary and mouse click means hundreds of unnecessary
mouse clicks. And I have many projects like this.

If there is an easy solution or a path to seek "the one mouse click on each
area" solution with existing tools, I am willing to hear it

Jami

Re: Analyzing surface elevations, lisp programmers?

Anonymous — Mon, 03 May 2010 12:52:01 GMT

Hi Jamiaho,

As a working practice, draw your bounding polylines all on one layer
with no other polylines on that layer.

From a coding perspective, it is then very easy to ask the user to
select one polyline for purposes of determining the layer name and then
the program can find all polylines on that layer and process them with
no further user input. They can be automatically numbered and labelled
at the centroid of the polyline (in general it will happen in order of
their creation in the drawing)

If you want a more complex set of objects to bound the areas, then you
could look at hand using the AutoCAD "Boundary" command or other
techniques to create the polylines in advance. The coding effort to
find these areas by pure logic will be far greater than anyone is likely
to do without payment.

Once the polylines are available, several programming approaches become
available.

One is to to add the polyline to the surface as an external boundary,
and then use the data analysis of that "surface" to get the required
data, followed by removing the boundary then adding the next one.

Another would be to query all the vertices of the surface which are
inside the boundary and the vertices where triangle edges cross the
polyline and have the program compute the values you need from that data.

Again the programming effort is significant. I doubt that any one would
do this for you without a commercial agreement. Will the program save
you enough time to warrant and outlay of $1,000, $10,000, $50,000?

You need to have a figure in mind and then consult with an experienced
programmer to get an idea of the real costs involved in programming it.

Lastly, all you want is a working solution, so don't specify the
language you want the solution written in. Leave that to the programmer.

Regards,

Laurie Comerford

Jamiaho wrote:
> Of course, the best solution would be just giving the command that does everything automatically on specified surface with specified elevation ranges, without me clicking on every area. But this would be more difficult to code, or maybe easier? I am not a programmer either.