Best Practices for adding survey data to an existing surface?

RE: Best Practices for adding survey data to an existing surface?

Douglas Hobyan — Thu, 14 May 2020 14:42:51 GMT

I just Export my XML and bring it into Civil3d as an import land XML file.. i make my edits, and then export it back out as an XML file and bring it back into SS10 .... This program is so far behind when dealing with surfaces. It pathetic to be honest.

RE: Best Practices for adding survey data to an existing surface?

MikeH — Tue, 12 May 2020 13:08:08 GMT

Thanks for the response David..

I am the surveyor so your statements ring true in that you must know how surfaces, triangulation and such work together with the software. We only use it because we have to. Which is why NO private consultants i have met in my 30 years of travels willingly use this software when allowed the freedom to choose. I am very aware of the apparent downstream benefits for large scale transportation projects. With that said we have suitable workarounds that involve using other software and then export/import xml files. Its just crazy that you cannot edit a surface and have those edits stay for the life of the surface. No surface is ever perfect, they all require edits.

RE: Best Practices for adding survey data to an existing surface?

David E. Stewart — Tue, 12 May 2020 12:51:56 GMT

MikeH: As a former surveyor and now a modeller, my solution is to have the surveyor produce the surface. After a few times, the surveyors will figure out how to change their surveying techniques to suit the software and to produce a workable surface. I have used civil design software where I could do 90% of my surface modelling / office work in the field, just by coding my points correctly.

There will be a lot of short term pain, but there will be long term gain. Your survey crew must be familiar with office work and your designers must be familiar with field work.

This is the tool that you have to use for your contract, you may not like it as you only see a small portion of what the software is capable of doing, but at the same time, this is the right place to complain as the people that have the power to do something about it, listen to this forum.

My job is to make this software work better. Some of my solutions don't make sense to the average user until you explain why. A surveyor must be able to process their own data and produce a surface in an efficient manner. Gone are the days when a surveyor when a survey does not QC/QA his own data.

This is my 2 cents worth on this matter.

RE: Best Practices for adding survey data to an existing surface?

MikeH — Mon, 11 May 2020 21:22:41 GMT

Well the newer versions are even worse, you cannot make any surface edits that last longer than one surface rebuild. Therefore you must do all edits each time you update the surface.

RE: Best Practices for adding survey data to an existing surface?

MaryB — Mon, 11 May 2020 21:10:37 GMT

Well, SS10 is essentially SS4, which is probably closer to eight years old by now. Yes, V8i is "so far behind" because I believe it hasn't been updated in at least 4 years, and it won't be updated again. It's so far behind because it's so old...

RE: Best Practices for adding survey data to an existing surface?

MikeH — Mon, 11 May 2020 16:23:22 GMT

[quote userid="851613" url="~/products/road___site_design/f/geopak-inroads-mx-openroads-forum/125013/best-practices-for-adding-survey-data-to-an-existing-surface/585897"]. This program is so far behind when dealing with surfaces. It's pathetic to be honest. [/quote]

You are 100% correct!

RE: Best Practices for adding survey data to an existing surface?

Douglas Hobyan — Mon, 11 May 2020 16:15:30 GMT

RE: Best Practices for adding survey data to an existing surface?

caddcop — Thu, 16 Jan 2020 14:15:46 GMT

One note on adding breaklines. When I was working with a stream as part of a survey, I was adding some JPT codes to connect breaklines so the contours looked more natural. What I discovered was that adding one breakline to close a gap between two other breaklines often resulted in different triangle orientation than had I simply used a flip face command. The new breakline caused other triangles nearby to reform in different orientations as well.

RE: Best Practices for adding survey data to an existing surface?

MikeH — Wed, 15 Jan 2020 23:16:30 GMT

Thanks Zen dude. I understand. Unfortunately we only get to use the weakest part of the software, the Survey side. I hear its really great on the engineering side of things.

RE: Best Practices for adding survey data to an existing surface?

The Zen Dude — Wed, 15 Jan 2020 23:02:25 GMT

I never said that the Flip Face functionality wasn't necessary sometimes, I was just stating that its use could be mitigated with stronger collection practices. I've been using InRoads, processing field data and building DTMs for 30 years and it's only until recently did we have the flip face functionality. So InRoads users have had to become desensitized to adding breaks where needed to reform triangles. It's clear that you are significantly stronger in CIvil 3D, and it's your software of choice, but understand that most of us here are InRoads users (or GEOPAK) and have come to terms with it's positives and negatives. A negative is that we've had to add supplemental breaklines so that we could lock down those triangles, but we accept that, move on, and focus on the stronger aspects of the software.

RE: Best Practices for adding survey data to an existing surface?

MikeH — Wed, 15 Jan 2020 22:04:39 GMT

No offense but the algorithm is complete garbage then. I don't need a TIN explanation, I've been doing this 30 years and have never ever had the TIN issues I've had with this software.The field crew has no control over how a program will determine how it will connect the dots (besides creating breaklines and even then it can't control how the adjacent points connect to them) Having them add random breaklines to simple ground shots in the field is just wrong.

I can QA/QC a surface in Civil3d very quickly and efficiently and it only needs to happen ONCE. Its not the field crews fault MS doesn't support having a real person QA/QC a surface. The one we see all the time is when you have 3 shots in a row and the tin pulls a long thin line from the 1st to the 3rd point. I know the TIN isn't supposed to do this but it does. Answer: Flip face.

In reference to the Zen Dude, We encounter irregularly shaped surfaces all the time both in survey and when designing complex finish grade surfaces and in these instances face flipping is a must. Even CadCop had an issue with this in his engineering design surfaces. It can be impossible to obtain accurately spaced shots in areas of dense brush and tress and such, or if the crew has restricted access. I prefer my surfaces to be under my control not just press the button and walk away. Thank you for the replies.

The answer seems to be 'don't complete any surface edits in the office. Just press the button and whatever happens, happens. Any edits that are made will need to be done multiple times over and over and over as more data is added to the surface'. Very poor structure indeed. If weren't forced to use this program due to the monopoly they have on highway departments we most definitely wouldn't. Its the most backwards setup ever.

RE: Best Practices for adding survey data to an existing surface?

The Zen Dude — Wed, 15 Jan 2020 21:44:36 GMT

The other added influence is the density of shots taken. If the density of shots is not uniform then the triangulation will potentially be inappropriately formed (requiring a face to be flipped). But it's not needed if the density is appropriate for the surface being collected.

RE: Best Practices for adding survey data to an existing surface?

Ray Thwaits — Wed, 15 Jan 2020 21:36:22 GMT

I beg to differ.

The way the algorithm works, the TIN is created by triangulating the surface as if all the points are random. It then compares triangle edges to breaklines and adjusts the triangles so that the triangle edges do not cross the breaklines. Once the TIN is created, every edge identifies a change in the surface slope. The edges are implicit breaklines. The only way to force an area to triangulate a specific way is to explicitly define a breakline. That's what you do when you flip triangle edges, whether in InRoads, OpenRoads or Civil3D. Civil3D's advantage is that it automatically logs that edit and applies it when the surface is re-processed. The analog in InRoads or OpenRoads is to create an explicit breakline in the model or a graphic element that can be imported each time the TIN is processed.

Missing data is simply missing data. If we look only at the points and lines that define the geometry of the surface, data is missing only if that lack of data results in an inaccurate model. The task of the field crew is to collect all data needed to create an accurate model. If the TIN doesn't accurately reflect the ground, something was missed. In a case where flipping triangle edges resolves the problem, the survey crew didn't miss a shot, they simply missed making the connection between two shots. If the survey crew had made the connection, you would not have to flip the triangle edges; additional shots would not be needed.

Please don't take this as an assault on survey crews. I've been on field crews and I've processed survey data. These are errors made on every (and I mean that literally) survey. A process is needed to reveal those errors so that they can be addressed. Part of the process for most surveys is scrutinizing the TIN and flipping triangles.

RE: Best Practices for adding survey data to an existing surface?

MikeH — Wed, 15 Jan 2020 19:26:34 GMT

Ray, that is 100% inaccurate. If the crew misses data, it produces bad data and flipping triangles will not fix it. Triangle flipping is 100% necessary to produce an accurate surface unless you have a scanned surface with points on 1' spacing.

Just because the software places triangle in a certain location does not mean that is where they should be to accurately reflect the ground surface. The software is smart but its not that smart. Other software handles editing once, this one doesn't

RE: Best Practices for adding survey data to an existing surface?

Ray Thwaits — Wed, 15 Jan 2020 19:19:39 GMT

When you flip a triangle edge, you are manually identifying where a breakline should be. The field crew failed to collect the breakline because they either weren't paying attention or, much more likely, it was too subtle for them to recognize. You should add the breakline to force more accurate triangle creation. If that causes nearby triangles to change undesirably, there were two (or more) breaklines missed and will need to be added in the office.

RE: Best Practices for adding survey data to an existing surface?

MikeH — Tue, 14 Jan 2020 19:13:26 GMT

This issue STILL EXISTS in OpenRoads Designer contrary to what the friendly Bentley rep told me over the phone. This is utter nonsense on an epic level. Days of time wasted editing the same triangles over and over and over again. I would love for someone to correct me and show us how Bentley allows triangle edits to actually HOLD.

RE: Best Practices for adding survey data to an existing surface?

Sean Duphily — Wed, 24 Aug 2016 12:22:48 GMT

Yeah, you can sort of think of it that way. Keep in mind, if you drop a line in where the vertices are not already part of the surface, it will triangulate to those from the break line:

Before (yellow line about 15' above base ground):

After adding it to the surface as a soft break line:

I highlighted the actual break line generated.

RE: Best Practices for adding survey data to an existing surface?

caddcop — Tue, 23 Aug 2016 20:55:06 GMT

So a Soft Breakline is sort of a Draped Breakline that only reacts to elevations when it crosses a breakline. If it crosses a triangle leg that is not a breakline, it will create a new triangle leg that follows its location and elevations?

RE: Best Practices for adding survey data to an existing surface?

Sean Duphily — Tue, 23 Aug 2016 20:41:41 GMT

Inside the Help section, they reference three types of break lines:

Break Line - Breaks are used to designate linear features such as edges of pavement, ditch bottoms, ridges, etcetera where an abrupt change of slope occurs. Any longitudinal element may be defined as a break line. Triangles will not cross a break line in the terrain model.
Soft Break Line - A soft break line is a break line, however, if it crosses a break line, it will not affect the triangulation and is ignored.
Graphic Break Line - A break line is a soft break line that is not stored in the terrain model.

We obviously understand the Break Line element. The two new ones however are either not defined all that well or difficult to understand how implemented. Actually though, it may seem like the Edit Terrain Model - Swap Line command may be utilizing the Graphic Break Line feature type. It happens, but it's not really stored.

As for the Soft Break Line, it should be defined as - A soft break line is a break line, however, if it crosses a break line, it will create vertices at the point of crossing and re-project the element to those new vertices.

For example, with a line added as a soft break line crossing a break line:

I drew a line from a spot elevation to a point on the edge of a driveway crossing the other edge of the driveway. Yellow elevations show elevation of the line where it intersects with the triangles...green are those elevations of the actual surface at the same points.

After adding the soft break line, three vertices are added and the triangulation changes as such:

You will notice that the elevation doesn't match what existing was (green) or where I drew the yellow line in space, but where it extrapolated between the endpoints and the breakline interception (purple):

Sorry ahead of time for color discrepancies...gotta love JPG conversion/uploads to the site. You should get the idea though.

As for soft break lines added not in contact with an already existing break line:

After adding it as a soft break line:

As you can see, the line reacts as a normal break line. The triangulation goes to where I actually placed the line.

RE: Best Practices for adding survey data to an existing surface?

caddcop — Tue, 23 Aug 2016 15:01:59 GMT

What exactly is a "soft" breakline?

Due to a number of issues, my terrain editing has primarily been in Ss2 and earlier. We can't get all of what we need out of Open Roads Survey and our clients are still in Ss2, so I have avoided much in depth Open Roads Survey work.

I assumed the reformulation of triangle has to do with the triangulation algorithm. When a new breakline is added, the algorithm looks for its "smallest possible triangle between three points" and finds a different group of points now that certain previously eliminated triangle are now acceptable due to how the added breaklines cause them to form.

RE: Best Practices for adding survey data to an existing surface?

Sean Duphily — Tue, 23 Aug 2016 12:56:07 GMT

[quote user="caddcop"]

I've even tried adding breaklines to force the triangles to form and retain edits, but found that other triangles can be effected by the added breaklines and will often change in a manner that requires even more breaklines to be needed.

[/quote]

Caddcop, just out of curiosity...have you experienced the same issues using the soft breaklines? Honestly, I haven't seen the behavior your speaking of myself...not that it's not happening, I don't doubt it, but just wondering if the newer feature type may alleviate the problem. The only issue I've seen with the soft breakline feature type is that it's not a supported feature in the older DTM format, so an export will keep the triangulation as shown in the terrain model until you re-triangulate the DTM, then they "disappear".

I too like the idea of an audit trail of modifications to the terrain model to prevent the issues Roadrunner is experiencing. It's one thing to disjoin the surface from the survey data, make changes to it, then re-join it because you're trying to add survey data to it...I could sort of expect the behavior that's being experienced (that's a whole different discussion), but another workflow that shouldn't have any issues (at least in my mind):

Turn off (from Survey Settings) Create Terrain Model for All Field Books
After importing survey data, you need to manually right-click field book to Create Terrain Model...
Make edits as necessary
Bring in add-on survey into new field book and create its own terrain model.
Use the Create Complex Terrain Model command to join the surface data as required.

The problem that I'm noticing (which I'm sure you have experienced as well) is that once you try to do an Append, the flipped triangles go back to the way they were. This just shouldn't happen. Like you mentioned...some sort of audit trail would be able to prevent this from happening.

If you do a Merge instead, this isn't the case...the triangles stay flipped, but there are other unwanted results I'm sure depending on the dataset. Without the audit trail however, I'm sure some other command would flip them back at some point even if the merge was an acceptable method for the dataset.

RE: Best Practices for adding survey data to an existing surface?

MikeH — Mon, 22 Aug 2016 22:33:37 GMT

Thanks for the replies Caddcop, you are one of the few that understand my blight. Your workarounds sound rather ingenious, but also signigicantly outside the realm of something we could implement. I guess its back to flipping faces for 4+ hours just to add 10 points to our surface.

RE: Best Practices for adding survey data to an existing surface?

caddcop — Mon, 22 Aug 2016 19:40:25 GMT

It was not too many versions ago that there was no Flip Face tool at all! At least, on the InRoads front.

We actually have been using InRoads for all projects, including Land Desktop and Civil 3D, by way of LandXML for the DTM, 2D linework for the figures and a custom XML report to make a PNEZD list for point import.

Since Civil 3D 2010, we have begun some processing of Survey in Civil 3D after getting a clean survey in InRoads. Once all edits were completed, we used a new custom XML report that preserves all of the linking codes with the D of the PNEZD and imported them using a custom Linework Code Set that contains all compatible standard InRoads control codes. As it turns out, we seldom use most of the codes that do not equate 1 to 1 between InRoads and Civil 3D.

I should point out that this only works using the "classic" InRoads Survey and not the Open Roads version. They do not provide the same support for custom XML Survey Reports in it and it is really tying my hands.

RE: Best Practices for adding survey data to an existing surface?

MikeH — Mon, 22 Aug 2016 15:08:15 GMT

caddcop, you are 100% correct. We have not been using InRoads for too long and are absolutely astonished with this issue. It causes us days of delays and unnecessary work when compared with doing the same thing in Civil3d. If we weren't forced to use is for our lone client that requires it there is no way in the world we would use this software, it is simply not efficient in this area.

RE: Best Practices for adding survey data to an existing surface?

caddcop — Mon, 22 Aug 2016 14:44:10 GMT

I have mentioned the volatility of triangle "face-flipping" edits in an earlier post.

I am a long time InRoads user and sometimes, this type of edit is needed, even with the best of survey techniques. I've even tried adding breaklines to force the triangles to form and retain edits, but found that other triangles can be effected by the added breaklines and will often change in a manner that requires even more breaklines to be needed.

In Civil 3D, the edits are saved in a sort of audit trail, so if you add to or change the surface, the rebuild process reads the audit trail and preserves (or restores) any flipped faces. InRoads/Open Roads needs to add a similar capability.