lidar

Mix 05 /  by Xuan Prada

Hello patrons,

This mix is not really a mix. What I mean by that is that the two topics covered in this video have a relationship between each other but also with a topic that we will be discussing soon in the USD series.

In the first part of the video we are going to be talking about ingesting lidar scans of natural environments in our pipeline. We will process the lidars to be used as heightfields. Then, we will extract some attributes based on the pointcloud data, later we will create additional attributes that can be used for scattering and lookdev.

Finally, we will export all the data to be used in a different 3D software or in a game engine. Or just to be used in Houdini. Total flexibility.

In the second part of the video we will explore the basics of scattering and distribution in LOPs. This video covers how distribution works under the hood. We will explore random functions and noise patterns to create natural scattering similar to what we can find in nature.

Almost 6 hours of content divided in two videos.

Info on my Patreon webiste.

Thanks!
Xuan.

Dealing with lidars /  by Xuan Prada

Hello patrons,

We haven't talked that much about lidar scanning, and it is time to say a few words about it. Lidar scans are a fundamental piece of the VFX pipeline, used by every single visual effects studio on the planet and counted by dozens on every film or tv show.

Sooner or later you would have to deal with lidar scans, that's why I have recorded this video, more than 3 hours of professional vfx training about how to use lidars scans.

In this video we will learn:

- What is lidar scanning.
- How we use lidars in VFX.
- How lidar technology works.
- Basics of working on-set with lidars.
- Lidar hardware.
- Lidar software.
- How to process point clouds.
- How to generate meshes for 3D work.

All the information on my Patreon feed.

Thanks!

Xuan.

Meshlab align to ground /  by Xuan Prada

If you deal a lot with 3D scans, Lidars, photogrammetry and other heavy models, you probably use Meshlab. This "little" software is great managing 75 million polygon Lidars and other complex meshes. Photoscan experienced users usually play with the align to ground tool to establish the correct axis for their resulting meshes.

If you look for this option in Meshlab you wouldn't find it, at least I didn't. Please let me know if you know how to do this.
What I found is a clever workaround to do the same same thing with a couple of clicks.

  • Import your Lidar or photogrammetry, and also import a ground plane exported from Maya. This is going to be your floor, ground or base axis.
  • This is a very simple example. The goal is to align the sneaker to the ground. I would like to deal with such a simple lidars at work :)
  • Click on the align icon.
  • In the align tool window, select the ground object and click on glue here mesh.
  • Notice the star that appears before the name of the object indicating that the mesh has been selected as base.
  • Select the lidar, photogrammetry or whatever geometry that need to be aligned and click on point based glueing.
  • In this little windows you can see both objects. Feel free to navigate around it behaves like a normal viewport.
  • Select one point at the base of the lidar by double clicking on top of it. Then do the same in one point of the base geo.
  • Repeat the same process. You'll need at least 4 points.
  • Done :)