Photogrammetry and lidar from various programs

SketchUp
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new to sketchup and looking for guidance. I’m going through the free online tutorials right now to learn up and I’ve done what I can watching some various YouTube’s but still ignorant to what is ultimately possible, so I figured id ask here as this could help shorten my learning curve drastically.

Looking to map my property for a school project as I’m not satisfied with the google earth images(they haven’t been updated). Im using my dji mini 3 combined with drone link to capture the data. I hope to import this information into agisoft metashape(will be new to me as well) to create photomosaic base map (2d). I am also learning about the 3d options and want to explore this realm in sketchup so I can try my hand at design work.

Being in Washington state, I have access to lidar information. Ive tried importing some of the DTM but the files are so huge and contain a large portion of what I don’t need. I still can’t figure out how to select the portion I need and delete the rest, if possible(this should show my current skill/knowledge level of sketchup, lol). basically I only need 20-40 acres worth and not the several sq miles. Washington state also has: DSM Hillshade, DTM Hillshade, DSM, DTM, Metadata, Point Cloud.

Im just learning now about arc gis (esri) and very interested and also curious how this can play into the mix eg soil type, watersheds, etc.

So, I’m here to ask for help in making sense of all this fantastic info. My thoughts are to use the metasoft content and implement that into my sketchup designs. Is there a way to utilize the lidar information in an overlay of sort to ensure accuracy? same with arc gis information; how can that be applied if at all?

Im also interested of learning to figure out how to show the final product. Can a file (Kml or kmz?, I can recall) be used into view it in google earth?

Thanks for the help! I’m really excited to learn how to navigate this for a solid final product.

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another thought just came to mind; possibly using the lidar meta data or point cloud in metashape to collaborate with the drone content as I’m creating everything, then import to sketchup. I’m new with arc gis too, but could it be possible to apply this concept to arc gis. sorry for the ignorance, I’m super new to all this. I’m trying to envision a work flow of sorts while not knowing all the tools so this will help me understand which of the many tools and functions I need to work with and learn.

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Also, Arc Gis will be handy as the county has that information and I could use that to get accurate property boundary lines. And it has the added benefit of being in the format that they use. I guess to sum all of this up, I’m tryin to get the information to be compatible with all the different programs with an enhanced resolution acquired from the drone work. I know I have much to learn, but any pointers would be greatly appreciated.

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Try this ArcMap LAS data to 3D Terrain Model in Sketchup - #2 by mihai.s

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Not knowing what your project is about, if it is something related to 3d modeling on the property, what you should use isn’t the Gis info you collect, but the info from Dji scan you can use.

I don’t know exactly what you can export directly with Dji software, but in Metashape, which I only own the standard version, what you can do is the point cloud and triangulated 3D model fully textured.

Using Metashape Standard you can:

  • Create a high density colored pointcloud
  • Create a triangulated model using some options
  • Project textures on the model with as high detail as your GPU can handle

I don’t know if that model will be accurately scaled, rotated or geolocated with the standard version as I have only used Metashape to create models from phone cameras. All our geolocated pointclouds are received as topographical surveys, which are also created with the use of drones, but they use software that is equivalent to Metashape Pro, which I don’t own, and are provided by professional topographers which master workflows that I also don’t master.

So, if you use Metashape pro, I’m sure you can extract that kind of information and generate a lot more info, and get really accurate with geolocation and scale as well as generate orthophoto maps.

However, if you use Metashape standard, like I do, you can circumvent all that using Sketchup.

Workflow 1:

  1. Generate the 3D textured model in Metashape
  2. If your model is big, with a lot of textures, generate a second model by decimating the first and lowering texture resolution. Lowering texture resolution can be done manually from the original textures but decimating should be done in Metashape.
  3. In Sketchup create a new file and geolocate it. This will import a rough 3d terrain from the online data sources you have available in Sketchup. This will be your MasterModel.skp
  4. In Sketchup create 2 extra files and call them something like LowResTerrain.skp and HighResTerrain.skp
  5. Import the decimated 3D textured model from Metashape into LowResTerrain.skp and the original undecimated file into HighResTerrain.skp
  6. Be careful to position the models in the same reference point which should be the origin of the axis in the sketchup model.
  7. Inside Sketchup MasterModel.skp, import the LowResTerrain.skp file
  8. Draw a line anywhere and select it as well as the imported file. Create a component and call it FinalTerrain. You can erase the line.
  9. Now carefully place the FinalTerrain aligning it with the rough 3D terrain generated from Sketchup geolocation. Move, scale and rotate it. You can use several plugins to help you with that. Make sure vertical edges of location feature stay vertical, as probably it’s harder to find horizontal planes.
  10. In the end you can get inside FinalTerrain component, right click the LowResTerrain inside it, and find the reload command in that context menu. Replace it with the HighResTerrain.skp
  11. If you want to have both the final LowResTerrain as well as the HighResTerrain just duplicate the FinalTerrain component, make it unique, and use reload inside of that component

You should end up with:

  • Sketchup generated terrain
  • HighResTerrain inside a FinalTerrain Component
  • LowResTerrain inside a FinalTerrain#1 Component

You can discard and purge any info you don’t need.

The LowResTerrain is only needed if your terrain and textures are hard to deal with in Sketchup.

Latest Sketchup versions are a lot faster at dealing with high geometry and high resolution textures if you have a lot of GPU memory, so I urge everyone interested in this kind of workflow update it.

Workflow 2 - With Sketchup Studio/Trimble Scan Essentials.

The way I now do it using georreferenced pointclouds:

  1. Use the pointcloud generated from Metashape in Trimble Scan Essentials
  2. Generate ground mesh
  3. Model any extra buildings and features you need in Sketchup.
  4. Create a component with Ground, Buildings and Features
  5. Export this component into Metashape as a new mesh
  6. Project Textures onto that mesh in Metashape
  7. Export the file again with textures
  8. Reimport it into Sketchup

Workflow 3 - Mixed Approach

Generate terrain with Trimble Scan Essentials
Model hard features with Sketchup
Generate organic features in Metashape.
Mix them all in Metashape if you want to project textures
Reimport them all into Sketchup already textured.

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