[abenedik]

I see now that you should just pass null for the textureCoordinates parameter and not an empty array / list. If the textureCoordinates parameter is not null then the code compares its length to the number of positions.

I will update the code to prevent this exception in the case of empty array / list.

Btw., if you will need to generate texture coordinates, then you can use the methods in the Ab3d.Utilities.MeshUtils class: GeneratePlanarTextureCoordinates, GenerateCubicTextureCoordinates, GenerateCylindricalTextureCoordinates. See "TextureCoordinatesGeneratorSample" in the Utilities section of Ab3d.PowerToys samples for more info.