IDMapper add-on verified for Blender 4.1


I am pleased to announce that IDMapper is now verified for Blender 4.1. 

It has been tested against version 4.1.1 of April 16, 2024, and no changes were needed.

Blender 4.0 introduced quite a few breaking changes, so this version is not backwards compatible with 3.x

Although no new functionality was introduced in this release, please be aware of the following:

  • IDMapper can currently not work with facemaps, because they are no longer supported in 4.0. This may change in the future (hopefully, see this discussion) and if possible I will try to get this back into IDMapper. Meanwhile, I did create a small, free add-on to make selecting faces from facemaps possible in 4.0 which may be useful in some workflows.
  • Color picking in Face Paint Mode (with the S-key) is no longer restricted to the 3d-View area, so colors can be picked from anywhere in the Blender application (although still not outside of it).

IDMapper simplifies creation and editing of vertex color layers that can be used as ID-maps in texturing software like Substance Painter or Quixel. It aims to reduce the time it takes to create an ID-map significantly, especially for complex hard surface models. It uses powerful heuristics to create an ID-map from scratch and lets you interactively adjust the results. It offers options to use existing information, like uv-seams, but can also intelligently assign the same color to similar mesh parts. 

The new version is available on BlenderMarket.

This previous article showcases some of IDMapper's functionality.

WeightLifter add-on verified for Blender 4.1


WeightLifter has been verified for 4.1 compatibility. It has been tested with the 4.1.1 version of April 16, 2024  and no modifications were needed to make it compatible. If you still encounter a bug, please let me know so that I can have a look at it.

WeightLifter is available on BlenderMarket. This update is free for customers who bought previous versions of WeightLifter.

WeightLifter is an add-on that can calculate all sorts of information and store this into vertex groups or vertex color layers. It can for example determine the visibility of vertices for a certain camera or the distance to some light source and much, much more (the add-on comes with a 30 page fully illustrated manual), information that can for example be used as a density map in particle systems. You can even bake this information if your scene is animated. 

The future

The code in the add-on is very old (10 years, which in Internet terms is ancient) and it does show its age in the way it is structured and also, as I experience myself, it is not very fast, especially on large meshes.

I was tempted to modernize it, and improve its speed if possible, but this might also be an opportunity to add features. So if you have an idea or suggestion, please drop me a note in the contact box at the top right of the page or via BlenderMarket and I'll be happy to consider it.

In its current form it is unlikely it will be supported beyond Blender 4.2 LTS

Floor board add-on (a.k.a. planks) updated for Blender 4.1

It is always good to hear that people are using an add-on, and this time I got a request to update my floor board generator for Blender 4.1.

Blender changes all the time and this time 4.1 even broke the old version of the add-on. Fortunately it was pretty easy to fix, so I am happy to announce that a new version is available on GitHub. [click download in the upper left corner]

If you want to know more about what the add-on can do, check this older article on my blog.

This version also incorporates a few small tweaks:

  • the bevel modifier now uses percentage as the default. This gives more consistent behavior across different patterns,
  • the bevel modifier now also has the harden normals option checked, which gets rid of quite a few shading artifacts,
and a new pattern: Chevron

Add-on to fit a cylinder to vertices

I previously updated two small add-ons that can fit a line or a plane to a collection of vertices and was asked if it was possible to create an add-on that fits a cylinder.

That is a bit more challenging though, but luckily there are people who spend some serious time on designing an algorithm and even providing code (see references below).

Based on that I created a small add-on that can indeed fit a cylinder to a collection of selected vertices. Note that it fits a cylinder where the vertices lie as closely as possible on the surface of the cylinder (see image). If you want to fit a cylinder that encloses all vertices, so more of a solid rod, simply use the linefit add-on and align a cylinder to the best fit line.


Simply download from the repo and install and enable the add-on from this zip-file.

Then select the mesh with the vertices you want to fit the cylinder to and select Fit cylinder from the Add menu (in edit mode). The new cylinder object will be added as a separate object that will be in edit mode.

Code availability

The code is available in this GitHub repository.


The cylinder fitting code was adapted from code in Xing Jiepan's repo, which in turn was based on the algorithms described in this paper by David Eberly.

To remove dependencies on external packages (except numpy, which is included with Blender), we replaced calls to the scikit.optimize.minimize function with a different implementation of Powells' minimization function from the Sherpa code-base of the Chandra project. 

 and updated for Blender 4.x

Always happy to see any of my add-ons being used, even if it's a really old one, so based on a BlenderArtists request I updated and

Planefit adds a plane (=face) to your mesh that fits any selected vertices as well as possible (details in this post), and linefit is similar and adds a line (=edge) (details here). The articles also explain the math involved a bit if you are interested.

The updated add-ons can be found on GitHub:

Both add-ons can be downloaded in the same manner: Near the top right of the linked pages is a download button; click it to save the .py file, then (re)install the add-on in the usual manner.

Technical details

For any nerds out there: even though the commits seem large, that's mainly because I now use the Black formatter in all my Python projects so lots of whitespace was changed 😁. The actual change to was only 1 line (the current line 116): the loop_total property of a polygon is read only nowadays so we cannot (and need not) set it: It is automatically updated when we add the vertex indices.

The change to was a bit more involved, mainly because it was even older: Properties in an Operator are now annotated class variables (and have been since version 2.8 I think), so we had to change line 53 from

size = bpy.props.FloatProperty( ....


size : bpy.props.FloatProperty(...

A small but necessary change that does not even give you a warning anymore, so something to look out for if you revisit very old add-ons.

Likewise, the function bpy.utils.register_module() doesn't exist anymore and had to be replaced by bpy.utils.register_class()