In the following the used software is listed and described in more detail.
Feature Manipulation Engine (FME)
The tool FME enables the creation of complex data conversion workflows by combining a multitude of transformers supporting a range of formats. FME can be used to prepare datasets for manual modeling or even to develop entire workbenches for creating new models.
SketchUp is a 3D modeling software that is used in areas like architecture, civil engineering and design. It is actively developed by Trimble Inc. and offers a wide range of extensions in the extension warehouse.
SketchUp comprises multiple editions: SketchUp Free runs in the browser with limited functionality. SketchUp Pro is the full-featured and fee-based desktop edition with the ability to install all extensions.
For a lot of use cases SketchUp Make 2017 is an alternative, as it desktop-based and allows the usage of extensions. Furthermore, it is free of charge and can be downloaded here.
CityEditor is developed by 3DIS GmbH and can be installed as SketchUp extension. It enables SketchUp to import, edit and export CityGML datasets.
CityEditor is offered in a lite, standard and professional version. Only the professional license comprises the functionality of importing point clouds (.xyz, .csv). A detailed comparison between licenses can be found in this document.
More general software overviews can be found here: