Import point file ASCII problem

[phil.pritchardN7HPY]

I am trying to import the attached ACSII file into civil 3d but it does not like the file probably due to the projection not being right. So I created a surface and then imported the file under DEM files. I used the project British national grid to import the file as my drawing is British National Grid. Nothing appears but in the Surface properties when selected - the maximum and minimum values are too big? 

any ideas? 

[doben]

I was able to create a surface but there are over 13,000,000 points! (see attached) and it's slowing things down.

Can you get the points in another format so you can use recap?

[phil.pritchardN7HPY]

No this is all i can get as it is exported from infoworks icm. 

[tcorey · Accepted solution]

Why are you trying to import this into a TIN? Create a Grid Surface (Create Surface from DEM) and this will work much better/faster. I imported this as DEM and it took a minute. You will need to change the file extension to .dem.

Thirteen millions points will kill a TIN surface, but is more manageable as a Grid surface. Don't expect things to happen in a split second, but it will be way faster. Wait times of 30 seconds are better than wait times of ten minutes, right?

Here's your surface with 1' contours:

And here are the Statistics:

[phil.pritchardN7HPY]

thanks, i created a grid surface and then imported the .dem file. I get the attached image! No idea what is going on. 

i need the surface to be able to modify it for a flood model. 

[ChicagoLooper · Accepted solution]

As per the esteemed @tcorey, it can be done but you'll have wait a minute or two for the tin surface to materialize because you have a lot, lots and lots, of data. BTW, you don't have to change the extension, you can leave it as an .asc file.

First you'll need to create a surface in Toolspace. For the definition of that surface, you'll need to add a DEM . You can keep the asc extension as-is (you can change it but it's not mandatory to change ext.). The DEM's CoordSys, however, is blank so you'll have to 'add it' by clicking the ellipsis (see image-1). Choose British Grid for the category and for coordinate systems available select OSGB 1936 British Nat'l Grid (see image-2). When you're done selecting, you'll get this (see image-3). You're Toolspace should look like this (see image-4). The isometric view with Realistic visual style will look like this (see image-5).

1-When you ADD the .acs file, you'll need to enter the CoordSys for the DEM by clicking the ellipsis...2-Choose Great Britain for category and OSGB1936.NationalGrid for the CS.3-When you see this, you can click OK.4-Modelspace and Toolspace. The dwg's CS is displayed at the bottom.5-Isometric view with Realistic visual style.

[phil.pritchardN7HPY]

hi, thanks for this. this is the method I used initially. see attached dwg. the only thing i can see or import is the dem model boundary. 

[Jeff_M]

To expand on what @tcorey & @ChicagoLooper have suggested, if you want to have a more user friendly surface that doesn't take so long to work with I have this suggestion which takes some time but once done is much simpler:

Once you have the surface built from the DEM, set the CreatePoints defaults to use no description, do not match the descriptions, and use no style or label style. Then use the CreatePointsOnSurfaceOnGrid, select the lower left corner of the surface, 0 rotation, 5m X & Y spacing, then select the upper right corner. It will take some time for the points to be created (about 5 minutes on my machine). Now Export the points to a point file, using the PENZ format. Start a new drawing, set the coordinate system, create a new TIN surface, then add the PointFile to the definition.

The surface will now be defined from 132000+/- points instead of 13+million, with little loss of detail.

DEM Surface 0.5m gridTIN Surface 5m grid

[phil.pritchardN7HPY]

any chance one of you gentleman could upload me a copy of the ground model in a format i can use please from your own conversions? 

[Jeff_M · Accepted solution]

Uploading the dwg file won't do much good, as the path to the DEM file is saved in the dwg and cannot be changed (at least i couldn't find a way to do so). I am attaching the point file I created for a 5m x 5m grid that you can insert to a TIN surface.

[phil.pritchardN7HPY]

thanks Jeff, this now works!