Decimation and Remeshing

Many 3D Creation tools have added these features in one way or another. Zbrush, Blender, even Rhino (since version 7.0 with the Quad Remeshing tool) have tools that allow you to quickly reduce the amount of polygons on a mesh. The main issue with this approach is that the result is not 'clean'. So in some cases texturing or modifying the asset may be more difficult, and the result is possibly not as optimised as it could be.

So it depends on how important and big is the asset (at least to start) and how much time you are willing to spend on it.

The Decimate and Remesh modifier can be applied in the Modifier panel in Blender after selecting the model in Object mode. Once applied you can play with the large number of parameters to get the best effect on your mesh.

Adding a Decimate or Remesh modifier to your asset.

Decimate Modifier examples

Here are some examples of what Decimate modifier does to simple shapes.

Using the Decimate Modifier in Blender

Remesh Modifier Examples

And some more examples using the Remesh Modifier.

Using the Remesh Modifier in Blender

Remesh Examples (Object Data Properties panel)

The Remesh tool is in the Object Data Properties panel after selecting the mesh you'd like to remesh. it is sometimes more accurate than using the Remesh modifier.

Using Blenders Remesh settings

Note the Sphere on the Remesh tool doesn't look any different as this asset did not work with the Remesh method. The state of the original asset will usually decide which method is the best to use.

Decimation/ Remesh Summary

These basic shapes are not the best examples of assets you would want to Decimate or Remesh, but they do show the results very clearly. And each asset requires it's own approach. There is rarely one method that suits all assets. The goal is the same however, your want the polygon count as low as possible, while keeping the shape of your asset.