Creating low poly models for buildings

Hi everyone!

[INTRO]:
I’m currently working on a project that includes an extensive library of high poly building models. The web engine in which we are planning to operate them seems not to handle such a large amount of complex geometry, so low poly models for “Bake Selected to Active” have to be made.

The quality of geometry those models should have is approximately the same as shown on the images below: respectively, “Figure 1” is the original model, “Figure 2” is low poly. While all significant (large) elements of the facade should be preserved, small ones (e.g. windows, shallow depressions, some sorts of mosaics, etc.) are ignored in terms of geometry.

[THE PROBLEM]:
While talking about simple and repeating buildings, it’s easy to do low polys mannually: I can just make one model and copy it for all buildings of the same type. The problem is that the library contains a large number of unique and much more complicated buildings. Here’s an example of complicated building I’m definitely going to have troubles with: https://drive.google.com/file/d/1mxEa5jaJ5__obxidG_2YZnwNTbRUcYWH/view?usp=sharing

[THE QUESTION]:
So, is there any way to “automatize” the process of low poly modeling or at least to make it a little bit more easier for hard surface objects? Saying ANY here I mean literaly anything: a plugin (paid ones are just fine too), some Blender tricks I might have missed, a combination of those – anything, any idea you have.

I clearely realize that even after using the most “smart” plugin, there will still be a lot improvements to final geeometry, but if it’s somehow possible to at least save time on creating basic forms of the buildings without that crazy pixelhunting for main verticles – that’ll be great.

[MY ATTEMPTS]:
What I’ve tried already but with no luck:

  • Shrinkwrap a highpoly cube or same-formed parallelepiped on the target model;
  • Remesh target model using Blocks;
  • Remesh target model using Voxels and then Decimate;
  • Decimate target model by Seams;
  • Use AssetsGen plugin.

If anyone have any ideas on that kind of context, please help. Thanks a lot!

Maybe one possible method would be to convert the high poly building to a volume in geo nodes and then convert that back to a mesh that is lower poly… but I am unsure if this method would result in clean geometry…
Or one other possibility is to use the bounding box of certain components (for example the balcony objects) and use their bounding boxes as primitives. Then just combine all the bounding boxes… this of course would require you to separate certain components.
This is what I can think of off the top of my head… hope it helps! : D

For the remeshing part try a remesher like this: https://exoside.com/quadremesher/
Works very well even in complex situations.

I’d recommend thinking about making the whole project a bit more modular with trim textures, or maybe a combination of fully baked facades and trims. (but not knowing the full extent of the project, this may not be optimal).

Hope it helps!

Did a quick test with the Quad Remesher, not the best job.

What’s about the decimate modifer… 16390 vs 2372 faces

…i don’t thing any batch mode conversion would help because the quality seems to be check needed for ever single one… ??

Sounds interesting. I’ll give it a try!

Unfortunately there’s not so much time for moduling, I have to go with those complex models.
Thanks for Quadremesher advice!

Direct decimation oftenly leads to planar groups of faces deformation :frowning:

Is the web engine you plan to work with capable of dealing with Ngons?

Mostly it is, but some times issues on auto-LOD take place.

1 Like

Sorry for the off-topic. Is it this, what are you drawing?

image

It is my hometown :slight_smile: :face_holding_back_tears: