Creating points from lines

User Q & A (Post Here)
#1

When I “Create points from CAD” at segment ends I get a ton of near duplicate points. This is because I’m using an offset line as a source for point creation. An offset source line that has horz and vert nodes in the same place results in an offset line with those node in slightly difference places. When you create from CAD on that line, nodes are created at both nodes at tiny distance apart.

When I line is elevated the created nodes are all vertical. I don’t fully understand the resulting nodes created when using the offset command, I do not always get consistent results of created nodes depending on if source nodes are horz/vert, especially on corners and angles.

On top of that I can’t find a way to batch delete duplicate points; I can select all duplicate points but it selects all points and not just the duplicates. What good could that ever do?

Is there a workflow to prevent this?

Thank you.

#2

A better way to go about this would be to use the RPS Point Creator. Take a look at the command instructions here, RPS Point Creator Command. This will solve the issues you get from create from CAD.

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#3

Wouldn’t have thought I’d need a specialty command to do something so simple and core to the purpose of the software. That’s unfortunate, thank you.

#4

I’m not saying it’s not possible to get what you want done with the core tools of TBC, just that the easiest way would be Point Creator. Can you post an example of the linework that you are working with and I’ll see what it would take to get this accomplished.

#5

Optimize Linestrings will strip out duplicate nodes and also nodes on straight grades between nodes and also nodes on curved sections of lines that are chorded etc.

Offset line - offsetting a line in 2D is easy. Offsetting a 3D line with just a lateral offset is not so easy because at inside corners there are two possible elevations (at least) on every corner. Getting elevations right on an offset line is also not as simple as just transferring the elevation from the source to the target because if the lines are significantly different in length the slopes of the offset line if shorter / longer will be steeper / shallower than the source if you have sparse elevations along the source and do not densify in between (even with a 0% cross slope).

This is why we wrote Slope Designer, Multi Offset Line, Linestring Optimizer and Point Creator - to help you to get this right and make this more robust. All of the above are “3D Engines” that play a part in e.g. Slope Designer - you have to define how often you want elevations or slopes interpreted and then use optimizer to clean out unnecessary data and to add back the true arcs of the source line and compute correctly through horizontal and vertical curves in a smart way. that way the offset lines have all the data needed and are truly 3D curvilinear lines that can be offset again and again. All corners are handled correctly and the elevation interpolation at an inside corner is handled in a smart way.

You can argue that anything we do should be core TBC - unfortunately that is not the case and we are trying hard to push the boundaries and constraints of TBC while eliminating bottlenecks, cant do’s and streamlining multi step processes making things faster, easier, more accurate and more automated - making you more competitive. I feel that we are innovating the product significantly but totally understand that not everyone wants to spend an extra $1085 per year to get the productivity gains available. If you cost the company you work f or $50 / hour then you have to win back 42 hours per year to pay for what we do - that is less than 1 hour a week and less than 15 minutes per day - we just saved a customer 14 hours on a 20 hour takeoff using just 3 of our tools - he just paid off in one day 30% of his annual fee and he will do that every week on every takeoff from now on. I think he will come out ahead this year as a result of a $1085 investment.

Appreciate that we are not for everyone.

Alan

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#6

I understand and appreciate your response. The main thing that keeps me from using RPS tools isn’t the money, it’s the need to be connected to the internet. If I could just purchase the tools and use them offline…

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#7

I use create at intervals with little issue. It does create a point at hor segments but I am usually looking for these. i will give the frequency a distance longer than my line and the only points created are those that are segments. ((For instance: I can leave (or change) my Corr sample distance at 50’, explode the surface, select a breakline, and create at intervals a distance longer than said corr. I will get a point every 50’ along the line at each triangle connection of the surface.)) Station/Offset snap always works great, input heavy but good. The Station Offset points macro is first rate and you can allow it to transform with the base line should it change. After any points are made you can use the connect points to create the line-string. There are some good macros that will aid in clean-up, etc that Rockpile has touched on in this thread but generally I use the above which are base functions with the exception of Sta/OS points macro. Hopefully this wasn’t redundant information.

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#8

Thanks Nate, that does solve the double point created problem but does so by not creating any points at any VPI locations. I figured out this is really only a problem when lines are elevated by spot text/leaders because most of the resulting VPIs are not created at the exact same location as horizontal nodes.

I also did some testing and it seems that when offsetting linestrings the resulting nodes are different depending of it source line contains any horizontal nodes. If source does not contain any vert. nodes the resulting offset line will have elevated horizontal nodes placed at segment ends (corners). If the source line contains even one vert. node the resulting line will contain all vertical nodes placed perpendicular at outside corners and nodes placed directly in corners of course for inside corners but no elevated hor. nodes at all.

This all aligns with what Alan was saying of course.

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#9

right, i guess what I am suggesting is a backwards workflow. Rather than offset a line and create the points, then clean up all the stuff you didn’t want - I am suggesting you create the points you do want and then create the line. You can speed up the point creation through an excel spread sheet as coordinates or HAL based import.
Cats and Hides and all that. And you stay in base functions.
It sounds like you are on a suitable path though

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#10

A quick 'n dirty fix that I’ve used to convert all VPI’s to elevated horizontal nodes is to export the linework to DWG/DXF and then re-import it. Those file types don’t support VPI’s so TBC segments the line between VPI’s. Then you can use workflows that don’t honor VPI’s without loosing anything.