Surface TIN line editing

[Anonymous]

I was wondering if there was a quick way to make the surface in the attached image fill out evenly in between the two contours without having to manually edit, swap, or delete each tin line.  I simply have a bunch of polylines with 1' elevation increments and would like the surface to reflect evenly between them. Thanks,

[ToddRogers-WPM]

Hey Brent. How goes it? So you created the contours from polylines? There are some options there. Set the Supplementing Factor really low, like to 1.0 and the Mid-ordinate distance to like 0.1. That should clean it up for you.

[Anonymous]

TODD! Long time no hear from.  It's going good.  Same chair, new name on the checks.  How about yourself?  I actually already tried that and it didn't work.

[ToddRogers-WPM]

It's going good brother. You know we got bought out didn't you?

[Anonymous]

No, I didn't know that.  You were my go to guy at TotalCad, but when WE were bought out, that gravy train ended. lol. Who are you with now?

[ToddRogers-WPM]

We are still Total CAD, but we have the Graitec logo. Graitec is a European company. Not much has changed really. Hey can you attach the drawing here and let me take a look at it?

[Anonymous]

Oh ok.  I told Dwayne and he was curious too.  As long as all is going well.  

Not a problem.  I had to remove the contour data from the surface due to size, but it's all there isolated.  Thanks again.

[ToddRogers-WPM]

I set the angle in there to 0.1 and it fixed almost all of them. By default it is set to 4.0. Wouldn't let me attach it, but try that and let me know.

[neilyj666]

As a general point, contours are not the best objects from which to build a surface - although I appreciate that sometimes it is all you have to go on - as the amount of data can really slow down the dwg.

You will almost always get flat spots to some degree in the contour loops (even if the all the Add contour options are ticked and the surface will only be accurate to the contour interval - what happens between the supplied contour intervals??. Ideally always get the original TIN (or LandXML) to ensure consistency between surfaces.

[Dexterel]

_AeccMinimizeSurfaceFlatAreas
And check swap edge, this will do it

[neilyj666]

Mostly this does work but there are occasions when it doesn't - I think it mainly depend on the initial contour interval.

It should faithfully reproduce the original polyline contours at the original interval but if you set the style to show a smaller interval you will get flat areas in the underlying TIN and if you are computing volumes then this is what volumes are based on and you could get erroneous volumes.

It may not be significant in terms of percentage error but it is something to be aware of and to take a pragmatic view depending on the end use of the surface.

[Dexterel]

Add polylines as brakelines and use supplement factor to get a equal vertex distribution.

Run the minimize flat areas multiple times, this will clean everything.

[Dexterel · Accepted solution]

Add the contours as Counter data and check everything.

Also use a supplement of about 5 now is 20 I think

[Anonymous]

Thanks guys!  ionescu_dragosWHU3X, it seems your solutions worked out very well.  It interpreted between contours that go up or down like I would have hoped.  Obviously it doesn't know what it can do between equal contours so this is clearly all it can do.  neilyj, you are correct in that they are not the best to make a surface with, but yes, for now it is all I have and I wanted to get as good as bad can get.  Todd, I left yesterday before I could respond, but I tried that and it did help, but wasn't as clear as what ionescu_dragosWHU3X did.  I'm sure you would have got it, but I set the deck (of cards) by leaving.  It was good catching up with you!

Thanks for all of your help!