3D scene preparation

Make scanned models ready for the web.

A 3D scan can look beautiful and still be too heavy for a browser. This beginner tutorial explains mesh topology, why scans often contain too many vertices, and how decimation can make a model faster without making it look worse.

5M-10M common scan size before optimization
~1M recommended vertices for general web viewing
Better UX faster loading and smoother navigation
Same visible shape, less geometry
Before decimation Dense mesh, slow browser performance
After decimation Cleaner mesh, easier to publish online
First concept

What is mesh topology?

Mesh topology is simply the structure that makes up a 3D model. You do not need to be a 3D artist to understand the basics.

Vertices

Vertices are points in 3D space. A scanned model can contain millions of them, even where the shape is almost flat.

Edges

Edges connect vertices. Together they form the wire-like structure you see when a model is displayed as a mesh.

Faces or triangles

Faces are the small surface pieces between edges. In many scanned models, these faces are triangles.

Why scanned topology is often too complex

Photogrammetry and 3D scanning software reconstructs surfaces from photos or sensor data. The software does not always know which parts of the scene are important to a human viewer. Because of this, it can spend thousands of tiny triangles on a wall, floor, table, or other flat area where only a few triangles would describe the same visible plane.

This does not mean the scan is bad. It means the raw scan is usually a production model, not a web delivery model. Before publishing, it is normal to create a lighter copy that keeps the visible shape but removes unnecessary geometry.

Why it matters

A browser viewer must manage limited resources

A desktop 3D application and a web browser are not the same environment. Web scenes need to load quickly and stay responsive.

Longer loading

More vertices usually mean larger files. Visitors may wait too long before they can even see the scene.

More memory use

The browser must keep geometry, textures, and viewer data in memory. Heavy meshes can push devices over their limits.

Mobile problems

Phones and tablets have less graphics power than workstations. Very dense models can stutter, overheat, or fail to open.

Poor interaction

Orbiting, zooming, clicking points of interest, and moving through a scene should feel smooth for the viewer.

Practical Kroscloud recommendation

For general web publishing, aim for around 1 million vertices. This is not a strict rule, but it is a useful starting point for models that should work well across desktop and mobile devices.

  • Simple objects can often be much lower.
  • Large outdoor scans may need careful testing.
  • Texture quality often matters more visually than raw vertex count.
  • Always keep the original high-resolution model as a backup.
Optimization method

What is decimation?

Decimation reduces the number of vertices and faces in a mesh while trying to preserve the overall shape.

Decimation is not the same as damaging your model

Beginners often worry that reducing geometry automatically means reducing quality. In practice, a scanned model usually contains a lot of geometry that no viewer can notice. If a flat wall uses 50,000 tiny triangles, it can often be reduced dramatically and still look like the same wall.

The goal is not to make the model as small as possible. The goal is to remove geometry that does not improve the visible result.

A safe beginner workflow

  1. Keep the original high-resolution model.
  2. Create a copy for web publishing.
  3. Decimate the copy in stages instead of guessing once.
  4. Check important details, edges, and silhouette after each step.
  5. Export and test the model in the web viewer.
1

Start high enough

If your scan has 10 million vertices, try a first optimized version around 2 million, then move closer to 1 million if it still looks good.

2

Look at the shape

Check the silhouette, thin details, carved edges, and important surface features. Flat areas can usually lose much more geometry.

3

Test the final export

Upload the optimized copy and open it on a normal laptop and phone. The best target is the one that looks good and feels smooth.

Step by step

How to decimate a 3D model in common tools

Different software uses slightly different words. Blender calls it Decimate, Metashape calls it Decimate Mesh, and RealityScan calls it Simplify.

Blender

  1. Open Blender and import your model.
  2. Select the model in the viewport.
  3. Open the Modifier Properties tab.
  4. Choose Add Modifier, then Decimate.
  5. Use Collapse mode for most scanned objects.
  6. Lower the Ratio slowly, for example from 1.0 to 0.5, then 0.25.
  7. Check the model from several angles.
  8. Apply the modifier and export when you are satisfied.

Tip: If the model is mostly flat architectural surfaces, test Planar mode too. It can remove extra faces from flat areas.

Agisoft Metashape

  1. Open your Metashape project.
  2. In the Workspace pane, duplicate the model so the original stays safe.
  3. Select the duplicate model.
  4. Go to Tools > Mesh > Decimate Mesh.
  5. Enter a target face count that should produce a lighter web copy.
  6. Confirm and inspect the result.
  7. If needed, rebuild or transfer the texture from the original model.
  8. Export the optimized model for upload.

Tip: If the dialog asks for faces rather than vertices, do not worry about an exact conversion. Aim for the recommended range, export, then check the model statistics and visual result.

RealityScan / RealityCapture

  1. Open the project and select your reconstructed model.
  2. Go to the SCENE 3D/TOOLS tab.
  3. Choose the Simplify tool.
  4. Use an absolute target triangle count for predictable results.
  5. Click Simplify to create a reduced model.
  6. Switch to the new simplified model and inspect it.
  7. Retexture the simplified model if you need textures in the export.
  8. Export the final model from the Model and Point Cloud export option.

Tip: RealityScan creates a new simplified model instead of overwriting the original, which is useful when comparing versions.

Before upload

Beginner checklist for a web-ready model

Use this quick checklist before publishing a scanned model in Kroscloud.

  • Keep a backup of the full-resolution model.
  • Create a separate optimized copy for web publishing.
  • Aim for around 1 million vertices for general web use.
  • Inspect important details after decimation.
  • Check that textures still display correctly.
  • Export in a web-friendly format such as GLB or packaged OBJ.
  • Test the scene on desktop and mobile if the audience is public.
  • Use higher complexity only when the viewing scenario requires it.

Kroscloud does not force one model complexity limit

Some projects really do need a very detailed model. For example, an internal desktop-only review, a specialist research workflow, or a controlled presentation may benefit from higher complexity. Kroscloud does not block those workflows with a hard vertex limit. For most public web scenes, however, an optimized model gives visitors a much better experience.

Next steps

Continue preparing your 3D scene

After decimation, export your optimized model and build the interactive presentation layer.

Metashape export

Publish Agisoft Metashape models as interactive browser scenes.

Read guide

RealityScan export

Export RealityScan or RealityCapture projects for web sharing.

Read guide

Photogrammetry viewer

Upload scans, add context, and share them with viewers online.

Learn more

OBJ uploads

Package OBJ models with materials and textures for upload.

Learn more
FAQ

3D model decimation FAQs

What is mesh topology?

Mesh topology is the structure of a 3D model: vertices, edges, and faces. A clean model uses enough topology to describe the shape, but not millions of unnecessary points on simple surfaces.

Why are scanned models so heavy?

Scanning and photogrammetry software reconstructs the surface from many measurements or photos. It often creates dense geometry everywhere, including flat areas where the extra triangles do not improve the visible result.

Will decimation make my model look worse?

Not necessarily. Good decimation removes geometry that is hard or impossible to see. If you reduce the model gradually and check the result, the web version can look very close to the original.

Should I always use exactly 1 million vertices?

No. Around 1 million vertices is a practical starting point for general web viewing, not a strict rule. Smaller models may work with far fewer vertices. Specialist desktop-only models may use more.

Does Kroscloud reject high-complexity models?

Kroscloud does not apply a hard mesh complexity limit because some professional workflows need very detailed models. The recommendation to optimize is about performance and visitor experience, especially on mobile devices.

What should I optimize first: geometry or textures?

For very dense scans, start with geometry decimation. After that, check texture size and format. A balanced model uses reasonable geometry and textures that are detailed enough but not unnecessarily huge.

Ready to test

Upload an optimized 3D model to Kroscloud

Create a lightweight copy of your scan, upload it, and test how it feels as an interactive browser scene.