3d Terrain from 2d spot heights

Kenny · 21 Sept 2010, 16:26

I've got a 2d CAD survey with spot heights and wondered if there was a way to convert to 3d terrain. This isn't a 3d point cloud so can't use cloud.rb as the points are all on the same plane. There's a similar discussion here http://forums.sketchucation.com/viewtopic.php?f=15&t=14409&st=0&sk=t&sd=a&hilit=cloud The website with the convertor is not in existence any more and I wondered if there has been a plug in produced since then. Tig did discuss a LISP routine to convert to a point cloud which could then be converted to terrain. I don't have Autocad however. Any suggestions gratefully received!

Kenny

Chris Fullmer · 21 Sept 2010, 18:53

Can you upload the 2d spot elevation file here for us to look at?

Chris

Kenny · 21 Sept 2010, 20:13

Chris, attached is the file. Thanks for taking a look.

Kenny

12708_OGL.zip

TIG · 21 Sept 2010, 21:32

If you have AutoCAD... I wrote an AutoLisp file to read the text value of text elements in a DWG and move them to their correct 'elevation' [z] with a new 'point' added at their insertion-point.

You strip a copy of the DWG back to just the required levels-text, then run the AutoLisp code and then save it...
You then import it into Sketchup... then select the cpoints and use a 3rd party plugin the take the imported cpoints [now in 3d] to make your mesh...

Here are copies text2d3dLISP.zip Choose the one that suits your DWG units m/mm etc - it's various metric versions so if its 'footric' adjust the code in a plain-text editor to suit - it's pretty obvious what the bits do...

You simply Appload the desired file in AutoCAD and then type text2d3d at the command line to run it, select all text and off you go - check a text entity's elevation before and afterwards to confirm that its 3d elevation is getting sorted as expected...

You can't import text into Sketchup [easily] - so the sorting must be done before the importing...

Kenny · 22 Sept 2010, 16:51

TIG, thanks for the LISP code but unfortunately I don't have Autocad. I do have Doublecad, will it work with that and if so how?

TIG · 22 Sept 2010, 19:02

@kenny said:

TIG, thanks for the LISP code but unfortunately I don't have Autocad. I do have Doublecad, will it work with that and if so how?

Kenny

DoubleCAD doesn't have Lisp...
If you confirm that the DWG you linked to is the required one I'll process it for you...

Kenny · 22 Sept 2010, 20:08

Thanks for the further replys. TIG also many thanks for the kind offer. As it happens I've just had an updated survey sent through to me with a slightly different site area as it's just been resurveyed. I should have checked this before but I'm going to ask the survey company if they also have a 3D version, which being a recent survey I would have thought might be the case. If they don't I'll be in tough again with the latest plan so don't do anything at the moment. Thanks again for the offer and I'll let you know.

Kenny

EarthMover · 22 Sept 2010, 20:32

@kenny said:

I've got a 2d CAD survey with spot heights and wondered if there was a way to convert to 3d terrain. This isn't a 3d point cloud so can't use cloud.rb as the points are all on the same plane. There's a similar discussion here http://forums.sketchucation.com/viewtopic.php?f=15&t=14409&st=0&sk=t&sd=a&hilit=cloud The website with the convertor is not in existence any more and I wondered if there has been a plug in produced since then. Tig did discuss a LISP routine to convert to a point cloud which could then be converted to terrain. I don't have Autocad however. Any suggestions gratefully received!

Kenny

I do this manually as I'm typically the one who also takes the spot elevation shots when I measure out a job. I then do my base map and draw curving contour lines which average out the elevation heights in 1 foot increments, then when I'm ready to make the grade mesh, I raise them to their Z height and use the Make Contours or more recently Fredo's Curviloft Junctions tool.

I'm not sure how this could be made into a plugin, other than perhaps a tool that would allow you click on certain points in a grid layout and prompt you for a spot elevation reading. Then averaging those readings into a point cloud or contour lines. I don't believe one exists, but it would save me a hell of a lot of time if it did!

You could also try Google Maps data and see how accurate it is given your elevations and perhaps go from there.

TIG · 22 Sept 2010, 21:19

I did it any way -see if this is anything like you want ...Levels.zip

Kenny · 24 Sept 2010, 09:56

That's great TIG, thanks very much. The geometry looks fine. I've also investigated whether the original survey is available in 3D and it's not, therefore I'd be very grateful if you could do the same for the latest plan attached.

There are a couple of issues. It comes in too small (1000 times), possibly because I'm using metres and you've done it in mm. Also it would be great if it could be overlaid on the original survey base as a separate component so I know where the terrain sits in relation to the site plan features. I'me very grateful that you've taken the time to do this and I realise this will take you more time, I've sent you a PM.

Kenny

12708_OGL-REV3.zip

TIG · 24 Sept 2010, 12:07

Here's a zip containing the original DWG stripped back.
The DWG levels only moved in 3d to their true-Z.
A SKP with these both imported [aligned] and 'meshed'...KennyTerrain.zip

Kenny · 24 Sept 2010, 14:51

TIG, thanks again, that's perfect! I've tried PMing you however the messsages are not appearing in my sent box. Let me know if you don't receive them soon.

TIG · 24 Sept 2010, 15:42

PM got and replied...

wloveland · 15 Dec 2010, 16:16

I have a similar problem, I have an autocad file that has a series of spot heights with the heights in text next to them.

I have run the autolisp program on them and now have them at their spot heights. But then when I export them into sketchup and click the contour button on sand box. It says that you must first select the contours to use.

Any Ideas what I am doing wrong?

Thanks

Gaieus · 16 Dec 2010, 02:32

Do you select them first? Are they not components or groups (in which case, explode first)?

(Welcome to SCF by the way - Will, isn't it?)

wloveland · 16 Dec 2010, 10:27

Thank you!

yeah I have selected them and they aren't in a group or component.

Gaieus · 16 Dec 2010, 10:38

But are they not individual ("small") groups/components either?
How about sharing the file here? (How big is it?)

wloveland · 16 Dec 2010, 11:49

I currently have this in Autocad, but when I transfer it to sketchup to use contours it doesn't work.

I have also tried to used point cloud and it doesn't work either.

Anyone have any ideas.

Spot heights.dwg

Gaieus · 16 Dec 2010, 12:09

It my answer to you here as "version 2" - i.e. if you have guide points (which are not geometry so the sandbox tools cannot handle them), use this plugin to triangulate the points
( Select all > Plugins menu > Triangulate points).

(I did not know your units to import so imported in feet as far as I remember but it took a couple of seconds to triangulate only so you can redo)

mesh.skp

JackHill · 11 Oct 2017, 16:08

I've tried really hard to sort a similar problem by searching the forums for answers but still can't do it. I have Auto CAD 3D spot heigh data and need to convert it into a 3d landscape terrain. I can't find any plugins that work on my Mac with Sketchup Pro 2016. Any help would be greatly appreciated.