Why do I need a terrain model to extract features?

[Stefan.Wieser.ecoMAP]

Hi everyone!

I want to extract some road lines from a point cloud. Why do i need to make a terrain out of it before extraction features? I just want to click on the points i need but when i do  Infraworks wont snap to the points and always go on height 0.

I also tried to build a model terrain but the classification is a mess. Like 100 categories and because of this colorful picture im not able to identify anything...and the classification is kind of a black box...I have a plain road...but the classification shows Low vegetation, high vegetation, millions of unclassified categories...when its just a road.

I really like the feature that you can choose a line and go to profile view and digitize on the profile...but if i dont get it to work i have to go back to cloudCompare

Any ideas? All replies are welcome...

[ramesh_sridharan]

@Stefan.Wieser.ecoMAP As I mentioned on the other post of your, you can try ReCap workflow as well. Looks like that's what you are looking for.

[Stefan.Wieser.ecoMAP]

...only if i could manage to get a RCP on the cloud. Why not implement the Tool in Recap? Why must everything in the cloud? I need to install Autodesk Drive (which i never need before). I need to install Autodesk Connector (which i never needed before). I need to buy a subscription to Autodesk Construction Cloud (Which i never needed before). Then i have a nice online screen where i change the weather in a tab...I just want to extract a line from a point cloud....nothing more.

I have a one man company with a sales volume of about 35.000 Euro per year. The only reason im still with autodesk ist the flex option. Everything else doesnt work for me. You are focusing on big companies, with big projects which is fine but you forget about the main thing a software company should do. Create software that works the way it should. I want to extract a line from a point cloud but all i do all day long is installing apps and services i never need.

I know you are not the one to blame...but autodesk is. And you are loosing customers. We small companies may not pay as much as big players but we are a lot. I already changed from Recap to CloudCompare and from AutoCad to Bricscad. Last autodesk product im using is Civil3d (as mentioned with the flex option).

Sorry for lamenting but i wanted to earn some money today...

[Karsten.Saenger · Accepted solution]

Hi @Stefan.Wieser.ecoMAP,

I understand your point and I'm with you. Big companies sometimes overlook the needs of smaller companies/businesses. And then it's difficult to treat everyone the same.

Let's focus on your problem in InfraWorks, without any additional cost. If you like, I can open a support case for you, and we work on a solution from there, let me know.

You mention that InfraWorks wants to have a terrain before you can extract feature lines of the point cloud. That is correct! InfraWorks is designed to simulate the real world. A real world has a terrain where everything is placed on – that's the concept.

You mention that you cannot create a terrain from your point cloud in InfraWorks, because the result is messy. Have you tried loading another terrain? For example, if you build a Model Builder model for your area of interest, it will come with a terrain from free SRTM data. It should work to load your point cloud into the Model Builder model and extract the feature lines from the point cloud then.

Regards,

Karsten.   

[Stefan.Wieser.ecoMAP]

Hi

The problem I have with the terrain provided by Infraworks is, that the generation is complete black box. I don´t know what Infraworks is doing and I have no option to control or adjust it. There`s just this simple button to create terrain and than barely nothing. Im doing professional work and as a professional I use technology to help me doing so. And I always have to know to some extend what the software is doing. Thats (at least for me) is the difference between a professional and just someone who knows what button to click and hope everything is fine...

I generate a lot of terrains out of pointclouds. I do this mainly with CloudCompare and a algorithm called (CSF Cloth Simulation Filter). There I have the same button like here but when i click on it the first thing I see is a link to the guy who programmed the filter with a full documentation of it. And as Im not as good in maths and programming i dont fully understand the documentation but quite enough to know what the algorthim is doing and how i can adjust it to my needs.

Back to Infraworks. I know the option to get a terrain via Model Builder and SRTM. But One Pixel in free SRTM-Data is about 90m x 60m in Central Europe and an uncertainty in height of few meters. I can also download an ALS-Terrain from my goverement with a resolution of 0.5m but it is still not the accuracy i need. Thats maybe sufficent for the most of your clients to do their work but im working in CM-accuracy. And as mentioned i have a huge 20GB Point Cloud with all the data needed for generating an accurate terrain model.

Long story short: I need a decent software to extract lines from my pointcloud and I thought i give infraworks a try. I really like the profile section view to generate linear feature from it. But i also need to extract features in a 3D-View and thats not possible because infraworks wants to put this lines on the terrain. So infraworks dont work out for me.

I now have done all my extraction with AutoCad. I just have to clip the pointcloud to smaller areas so i can work with a decent framerate.

Case closed. Thanks for replying anyway

PS: Last question. Why is Autodesk working with two different UIs? I mean there are apps like Autocad or Civil which really looks professional and there are Apps like Infraworks or ReCap which have some "feel good" interface. No menu on top, no ribbons just buttons somewhere on the screen...doesnt have a very professional look...just sayin

[Karsten.Saenger · Accepted solution]

Hi @Stefan.Wieser.ecoMAP ,

I agree with you that triangulation in InfraWorks is more of a "black box". The program calculates something and you don't know the numbers behind it.

But, the SRTM terrain I mentioned for your workflow to extract feature lines, is only used to have the possibility to create a section view. The extracted feature lines will not automatically be draped on the terrain. This way it's even possible to extract for example power lines from a point cloud, see https://knowledge.autodesk.com/article/Extract-Powerline-from-Point-Cloud-in-InfraWorks.

Regarding UI's, each Autodesk program has its own design, either influenced by historic reasons or on purpose. All AutoCAD-based programs share the same UI, but all other programs have their own specific design.

Regards,
Karsten.