Objective:

Learn how to create a selection of random points from a List of Points by using surface roughness to filter the points based on volume.

Note:

To start, you will need to download and import the Custom Block: Filter Points by Volume. 

Procedure:

1. Set-up:

• • Import your part,
  • Convert it to a mesh
  • Input your mesh into a Remesh Surface block to create an even mesh

2. Create Random Points

• • Add the block Random Points on Mesh
    • Set the spacing and amount to your desired value

3. Create the Volume to filter with

Since we are filtering by volume, we want to create a volume that randomly covers some of the points. There are a few methods to do this with the different noise blocks such as Simplex Noise, Cellular Noise 3D, and Surface Roughness.

• • Add a Surface Roughness block
  • Insert your model as the Body
    • Edit the Roughness frequency, amplitude, and seed value to change your results

4. Filter the points

• • Add the Filter Points by Volume block
    • Use the Surface Roughness as the Volume input
    • Set the Region to Outside

5. Optional: Create a list from the remaining points

• • Duplicate the Filter Points by Volume block
    • Set the Region to Inside to create the opposite selection of Points

And that’s it! You’ve successfully created two random selections from a list of Points.

Are you still having issues? Contact the support team, and we’ll be happy to help!

Download the Example file:

• Example file

• Custom Block - Filter Points by Volume

More on this topic:

• Using the Filter and Sort Block
• How to Convert a Custom Block to Accept Lists