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  I learnt about PixiEditor at the Libre Graphics Meeting in Nuremberg. It looks like the main focus is on creating pixel art for games. However, version 2.0 features a very powerful node graph tool. To compare it with GIMP, I tried to reproduce the Chrome Ball tutorial using PixiEditor. It took me two evenings to learn the necessary skills, as there are significant differences. Firstly, I don't need multiple layers; I can do everything I need to do with one layer and nodes. Even the gradient is a node. The biggest problem was the 'Panorama Projection'. PixiEditor has no filter or function like this. However, it does have a Skia Shader node where you can write your own shader in SKSL, a variant of GLSL. Initially, I tried to map the image around a sphere, which worked after a lot of learning and testing. However, the result was nice but not what I was looking for. Just before giving up, I had the idea of looking into the code of the GIMP/GEGL 'Panorama Projection'...

Prologue : I originally planned to publish this blog post during the LGM 2026 in Nürnberg. Sadly, however, the  image  from the museum's object catalogue is under CC BY-NC-ND 4.0, so I was not allowed to use it to create a VR panorama. Fortunately, however, the museum has given me permission today to use it under a CC0 1.0 license. At the Germanische Nationalmuseum , I discovered this 360° map of the Nuremberg area from 1581. I just had to convert this 360° round image into a panorama for VR glasses, especially as it is the oldest one I have ever seen – it is almost 500 years old! https://objektkatalog.gnm.de/objekt/La140   First, I removed the decorations in the corners and cleaned up the image. Then, using the workflow described in this old  tutorial , I created an equirectangular 360° panorama. Finally, I added metadata with ExifTool to enable Google Photos and other panorama viewers to detect it as a 360° panorama.    The embedded A-Frame I used s...

Since I wrote the original tutorial , GIMP has evolved, so I've created an updated version that makes use of the new features. The most important new features are that you can now use linked layers, layer groups and non-destructive effects. This tutorial discripes how to create this chrome ball with GIMP. First of all you need a equirectangular panorama . If you don't have one you can get one from HDRI Haven . For this tutorial I took this one: https://hdrihaven.com/hdri/?h=bell_park_pier This time I chose the 2k version because it is faster to process. Of cause you can use other resolutions if you like. Now create a new image with 2048x1024px and delete the background layer:   Then open the image in GIMP with "File -> Open as Link Layer..." and duplicate the layer. The "Open as Link Layer" gives you the possibillity to change the image later.   This is the background layer on which the chrome ball sits. We now need a second layer for the ball itself...