topic Re: Topo lines too detailed! in Documentation

Topo lines too detailed!

Patrick M — Thu, 06 Jan 2022 16:57:17 GMT

Anyone have a good workflow for simplifying large/complex topography for quicker modeling? I don't know why surveyors think we would need contour points 1/2" apart, but it makes modeling a mesh TEDIOUS!

I have certainly used illustrator to simplify contour vectors before, but typically end up tracing down overlapping contours or looking for contours that are deviated from their original position too far to be accurate... Obviously I can adjust the magic wand precision, but that only works if there are a lot of curves; in this case all pLines are straight segments... I may be workin on this mesh for days 😞 [thats not even the full survey... I cropped it down to do it in sections, the pLines are so complex AC is glitching with all visible]

Re: Topo lines too detailed!

SenecaDesignLLC — Thu, 06 Jan 2022 18:08:43 GMT

I've never done one that big but I to hate this issue, I end up doing a lot of work for a small topo pending the files I get.

Re: Topo lines too detailed!

Patrick M — Thu, 06 Jan 2022 19:56:07 GMT

yeah, this one has been 2 days trying to just get contours traced... and hoping I didn't overlap anything or mess it up in the process, because that's a "start over" situation 😞 Really wish there was an option for mesh like there is for morphs to reduce polygons!

Re: Topo lines too detailed!

SenecaDesignLLC — Thu, 06 Jan 2022 20:37:03 GMT

Just a thought, I used to use morphs to create my topo lines in certain situations Maybe if you used a morph with no thickness to get the initial lines down then reduce the polygons you might be able to then explode the morph and use the magic wand on the mesh with the lines from the exploded morph

Re: Topo lines too detailed!

Patrick M — Thu, 06 Jan 2022 20:49:56 GMT

that could work for sure... but I'd have to elevate each morph vector, which would be as tedious to select and elevate as it is to manually trace... seems any way I skin this, it's either super tedious or super imprecise

Re: Topo lines too detailed!

Patrick M — Thu, 06 Jan 2022 20:50:49 GMT

I have seen some people use Rhino as a way to reduce nodes; I just can't justify the extra cost and learning curve or what would amount to a one trick pony

Re: Topo lines too detailed!

jfaugustine — Thu, 06 Jan 2022 21:13:09 GMT

While this may not be helpful in your particular application, but I sometimes create a mesh that correlates with the meets and bounds of the property lines. I then elevate the property corners to their respective elevations, which provides a generalized overview of the site. I then go back and add selective contours as required for detail in, and around the project area.

Re: Topo lines too detailed!

Patrick M — Thu, 06 Jan 2022 23:55:02 GMT

yes, I would absolutely do this for most work; but some of my clients are dealing in such high end projects on large sites that they really require a full detailed topography for context, visualization, accurate building placement, etc. For this particular client, I even model distant mountain ranges, roads, etc. to full detail for high accurate renderings... but for an average project/client, I definitely would not be modeling 24" contours on a site this large

Re: Topo lines too detailed!

ryejuan — Fri, 07 Jan 2022 03:31:58 GMT

Looking at the contours scared the toot out of me! yeah kinda tedious to do and a bit waste of time. just for a fact that they want to get how much cut and fill they could save for this project other than the design and layout of the sturcture that would utilize the contour.

i have a question, have you asked the surveyor to give you xyz text files?

Re: Topo lines too detailed!

jan_filipec — Fri, 07 Jan 2022 09:18:35 GMT

I'm sure you know this, but contours are already an interpretation of the measured data, meant to visualise the topography on a 2D plan. So if you're going for precision, you shuld go a step back and as @ryejuan says, get the original precise data from the surveyor.

Then you can for example use gratis (and open source) Blender to generate the mesh with exactly the detail you think is adequate for you.

Finally you can generate the contours inside Blender or transfer the mesh to Archicad and generate them there, if you believe you need them.

More here:

https://community.osarch.org/discussion/683/

https://wiki.osarch.org/index.php?title=Blender_Topo_Mesh2XYZ

https://github.com/JanFilipec/Sverchok-Tutorials/tree/main/Mesh2XYZ

Re: Topo lines too detailed!

gpowless — Fri, 07 Jan 2022 12:55:27 GMT

This was probably the most complex I have done. 1:250 final scale

I received a .dxf from the surveyor and placed it on a storey well below the bottom storey then used it as a ghost storey for a 3d Site Plan storey (this is a template storey sitting below the walk-out footing storey) to create a 3d mesh using the boundaries of the outer most topo graphical elevation points. Then using the magic wand I was able to add contour lines using the polygon tool.

Using the 1st storey as 0 for the design and setting the reference level 1 to -100.00m elevation (it puts the real time elevation to 100m) and the building floor levels are referenced from 100m.

For the site mesh a site bench mark (could be a corner bar) I made adjustments to the reference level to correspond with that known elevation. (this takes some practice and some math)

Once the elevation point was made I made adjustments to each contour i.e. each contour was 0.5m above or below the next. Point elevations were then added using the mesh in line mode and added the calculated elevation.

A final grading plan was created by duplicating the mesh, placing it on a different layer and adding additional spot elevations as necessary.

Re: Topo lines too detailed!

Chris Grantham — Fri, 07 Jan 2022 15:34:27 GMT

Woof, I hate this problem! I have had some luck opening the dwg in Adobe illustrator and reducing the number of nodes in there. It still is a clumsy and imperfect solution at best, but I suppose it is something. Another option is to call your favorite civil engineer and have them take 20 minutes out of their day and import survey data in and reduce the number of nodes into something they might use?

Re: Topo lines too detailed!

Patrick M — Fri, 07 Jan 2022 16:00:04 GMT

XYZ files almost always come in with crippling high poly, if we can get them at all

Re: Topo lines too detailed!

Chris Grantham — Fri, 07 Jan 2022 16:11:37 GMT

I agree the XYZ import option is totally useless, and always smothers my computer.

Re: Topo lines too detailed!

jan_filipec — Fri, 07 Jan 2022 17:17:01 GMT

Strange, I use it regularly with no problems, the import time depends simply on the amount of mesh points and with correct data it always succeeds. Of course the resulting mesh can easily be too complex for Archicad, but that also simply depends on the number of points and not on the way you create the mesh.

That's the reason I suggested blender-it can easily handle meshes orders of magnitude more complex than Archicad, optimize and export xyz data of the desired detail level.

Re: Topo lines too detailed!

Chris Grantham — Sun, 09 Jan 2022 16:06:44 GMT

I will give the blender option a shot and see how it works. Something tells me i am going to have a ton of questions. ha!

Re: Topo lines too detailed!

Chris Grantham — Sun, 09 Jan 2022 20:52:02 GMT

Does Blender work on OSX?

Re: Topo lines too detailed!

Jp1138 — Tue, 11 Jan 2022 19:02:04 GMT

Yes