Auto Feature Line: Cannot Delete Curve

[mathewkol]

Grab yourself a regular old feature line with curves and use the edit tool to delete a curve.  Works right?  now try it with a feature line created from an alignment (and profile).  Remove the dynamic link so it's no longer connected with the alignment.  Now try to delete a curve.  I can't.  Can anyone figure out how to do this?

Is there a way to convert this "auto feature line" to a regular feature line so I can delete the curves?

One more thing, does anyone know how to remove ALL curves from a feature line all at once and not one by one?

Thanks everyone.  I have a customer with a 10km feature line with many curves and he needs to make PI's with no curves.  He ultimately needs a 3D polyline which represents his alignment/profile combination except that it needs to be drawn to the PI's and not through the curves.  I'd rather not write code if I don't have to.

[mathewkol]

So I'm looking further into this and I believe the "Create feature line from Alignment" tool may not be sufficient for my customer.  I was hoping this tool would hold the BC and EC elevaitons (bad assumption), but it doesn't.  It takes the curve midpoint elevaion and uses it for the PI elevation.  It looks as though I need to make some code.

Before:

After:

[doni49]

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@mathewkol wrote:

Grab yourself a regular old feature line with curves and use the edit tool to delete a curve.  Works right?  now try it with a feature line created from an alignment (and profile).  Remove the dynamic link so it's no longer connected with the alignment.  Now try to delete a curve.  I can't.  Can anyone figure out how to do this?

Is there a way to convert this "auto feature line" to a regular feature line so I can delete the curves?

One more thing, does anyone know how to remove ALL curves from a feature line all at once and not one by one?

Thanks everyone.  I have a customer with a 10km feature line with many curves and he needs to make PI's with no curves.  He ultimately needs a 3D polyline which represents his alignment/profile combination except that it needs to be drawn to the PI's and not through the curves.  I'd rather not write code if I don't have to.

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If you EXPLODE  a featureline, it will become a 3dpolyline with individual linesegments along what was the curve. 

Or are you saying he wants the CHORDs of each curve?  Meaning the featureline consists of the green and white but he wants the end result to be a 3DPline including green and red.

[mathewkol]

He needs the green and blue.  Exploding the FL is ok, but it will still have segments where those curves used to be in the FL (your whihte curve).  These segments need to be removed and my blue lines below inserted.

It's quite a strange request and I'm not really certain why he needs this.  The project is for a large gas line design; the alignment/profile are the invert of the gas line.

[sboon]

Sounds like he wants to get a 3d pipe length.

Steve
Please use the Accept as Solution or Kudo buttons when appropriate

[Neilw_05]

I don't have an easy solutionbut one approach would be to explode the alignment down to basic lines and curves, use QSELECT to erase the curves then join up the tangent pieces with Mapclean. WBlock the poly out to a new file. Close without saving. Re-open, import the poly, create a surface from the orig. FL and drape the poly on it. Not sure how to globally straighten the grades of the tangent pieces that fall outside the curves.

[mathewkol · Accepted solution]

Neil, thanks for the reply.  The soluiton isn't exactly yours, but it got me thinking.

1. I create a feature line from alignment using the tool with that name.
2. I offset the alignment 1m to one side and then 1m back.  Now I have a polyline exactly the same as the alignment.
3. I use a fillet radius of 0 to remove the curves and extend the tangents to the PI's.
4. I convert that polyline to a feature line remembering to place it on a new Site.
5. I use the "adjust elevations by refererence" tool to apply the elevations from the source FL to this newly created one.
6. I explode the new FL and voila a 3D Polyline.

Thanks to all for your suggestions.

[MikeEvansUK]

Food for thaught as I have not fully tried this out but I think..

You could just create a corridor model using the alignment / profile data with a Marked Point, set the incremental distance for Curves so that it is larger than the largest curve on the alignment.

Carefull tinkering with the increment for tangents etc should result in the model not drawing any intermediate curve points. It may be that you want to set the increment larger than the alignment then manually add the stations - Depends on the Vertical design.

You can then extract an AutoFeatureline which will be dynamic and not contain curves direct from the model.  Copy to site and it should become a normal FL ? Depends what you want to achieve with the FL.

[Neilw_05]

I wasn't aware that offsetting an alignment results in a polyline. Use elevation by adjacent was a great idea too. Nice solution Matt.

I'm wondering how you managed the grades on the tangent segments that extend beyond the curves.

[mathewkol]

Thanks Neil, it's appreciated. The PI elevations assume the elevation at the mid-point of the original curve. I made a video for my client, but I didn't attach it here. I will later today. It shows how the "elevation by adjacent" tool applies the elevation.