Grasshopper

algorithmic modeling for Rhino

I am currently working on building modeling through the use of aerial scan data. I have to process a large amount of data contained in a lidar point cloud. I treat the soil, vegetation and buildings separately. At the moment I'm having trouble creating mesh for buildings.

 

However, if you have other suggestions I am open to them. After several tests and different techniques, the best solution seemed to me to define the points that make up the roofs and then extrude everything. However, I can not do it well. I miss a "Concave Hull" function that works well.

 

My questions would be:

 

How to find the points that make up the roofs?

How to create a surface from these points?

 

I also tried Nik's technique to get there.

 

(NIK'S ZBRUSH COMMANDER - http://www.grasshopper3d.com/forum/topics/zbrush-is-now-a-grasshopp...)

Here's the link to the point cloud txt file. https://www.dropbox.com/s/dixrrd3t80f1oj6/CloudBuild_Light.txt?dl=0

Views: 3358

Attachments:

Replies to This Discussion

I, unfortunately, work with point clouds often. The best process i've come up with is to use cloudcompare (open source point cloud software) to segment and clean up the clouds, saving in smaller bites to .e57, which i then import into grasshopper via Volvox plugin. Depending on what i'm doing i will either bake the cloud or perform operations on it. Typically the cloud/plane intersection. This will give cuts that i can order points and average some curves.

Thank you for your answer !

I have already used CloudCompare to divide my point cloud into different classifications. I am also familiar with Volvox to import data into Grasshopper.

I'm not sure how to find planes and approximate curves. Would it be possible for you to join an example?

Thanks for your help.

its not finding planes, its intersecting the cloud with a plane (volvox/analysis), to create a planar set of points (project option in the component). 

you can then use various curve components to generate geometry; fit line, circle fit, polyline ect. 

Its not easy getting clean geometry out of point clouds, too much fuzz.

rough example

Attachments:

RSS

About

Translate

Search

Photos

  • Add Photos
  • View All

Videos

  • Add Videos
  • View All

© 2024   Created by Scott Davidson.   Powered by

Badges  |  Report an Issue  |  Terms of Service