CityEngine 2021.1 Release Notes


Drawing and editing of shapes and streets

Transform tools 

  • Removed the locked coordinate system functionality in the transform tools and replaced it with custom reference systems.
  • Added a new tool to define custom reference systems in the viewport located under Edit in the main menu.
  • Extended snapping functionality to geometry for the reposition and reorient handle of all transform tools.
  • Fixed the ToolTips for the reference system in all transform tools.
  • Fixed a bug in which the scale tool handle got distorted using the object coordinate system.


  • You can now snap to intersection points of guides and faces.
  • Fixed a bug in which snapping didn't work correctly when using the force planar mode or orthogonal snapping.


  • Fixed a bug in which snapping didn't work correctly for faces in combination with a length constraint.
  • Fixed multiple bugs to improve snapping when using arcs.


  • You can now store the current selection as a selection set using the tool option window of the Selection tool.
  • You can store and load dynamic shapes in selection sets.
  • When creating a selection set, you now have the option to overwrite an existing one.


  • The shape creation tools have a new Force New Shape tool option.
  • The Push Pull Tool has a new Force New Edges tool option.
  • Fixed several bugs with the Push Pull Tool related to shapes with holes.
  • Fixed a bug in the Push Pull Tool that prevented the removal of side-planes when reducing the extrusion to zero.
  • Fixed a bug that caused crashes when using the Push Pull Tool on edges.
  • Fixed a bug in the Rectangular Shape Creation Tool that prevented the creation of a hole in existing shapes.
  • Fixed a bug that led to extra vertices when creating a hole on a shape with a coplanar model.
  • Fixed a bug that caused a rule not to be automatically assigned to street nodes.
  • The Street Creation tools are now grouped as subtools in the tool options.


  • The Offset tool arrow handle is now easier to grab.
  • Undo/Redo is now more robust when using shape creation tools.
  • The tool options now have a vertical scroll bar.
  • Fixed a bug in the measurement tool in which the endpoint periodically could not be repositioned.

Terrain editing

  • Added the new Smooth Range function that creates a smooth transition between the edited and the original terrain.
  • Added the new Constant Gradient function that creates a transition with a constant steep slope between the edited and the original terrain.
  • The Smooth Range and Constant Gradient functions are available when aligning terrains to shapes.
  • Added a hot key for the elevation picker in the terrain editing tool for easier access.
  • Made improvements in the internal storage and handling of terrain edits that lead to smoother and more precise results.
  • Fixed a bug in which terrains with duplicate names were not selectable in the Align Terrain to Shapes dialog box.
  • Fixed a bug in which editing the resolution of a terrain reverted all elevation edits.

User interface


  • You can now duplicate and move Dashboards cards to other Dashboard pages.
  • You can now duplicate entire Dashboard pages.
  • Dashboard cards now show an error when referencing reports that are no longer present instead of silently using the alphabetically next report.


  • The viewport now renders shapes correctly with very small faces.
  • Improved render quality of models with normal maps.
  • Fixed an issue that caused render artifacts when shapes are self-intersecting.


  • Sliders for street shape parameters work reliably now.


  • Added the new Epic Games Unreal Editor mouse scheme (Preferences > General > Navigation Devices > Mouse).
  • You can now use the Crop Image tool when a scene isn't open.
  • All algorithms that use map layers, such as align terrain to shapes, are now considering the scenario settings.
  • Added missing translations for some preferences.
  • Improved the visual quality of the CityEngine application icon in the taskbar on Windows.

Import and export

All exporters

  • CityEngine no longer exports “No data” areas of terrains to 3D geometry formats.
  • The Merge Vertices option no longer removes very small faces when exporting to 3D geometry formats.

BIM/CAD support: IFC support

  • Added the buildingSMART IFC importer and exporter to enable visualization of BIM data.
  • The Autodesk DWG importer now reads vertex normals when present.
  • The Autodesk DWG importer now reads textures with absolute paths.
  • Fixed a bug in which Autodesk DWG wasn't listed in the import dialog box.
  • Fixed a crash when importing an Autodesk DWG file with certain spline configurations.

OSM: Better buildings in Get Map Data

  • Improved the OSM importer to support the OSM 3D buildings with more advanced geometry consisting of multiple parts and relations.
  • OSM buildings are now represented in a neutral white shading by default.
  • Fixed a bug in which a coordinate system wasn't suggested for the scene when importing OSM files only containing relations.

Datasmith (Unreal Engine)

  • The Datasmith exporter now stores metadata with finer granularity on instanced Static Mesh Actors. The parent actor still receives all the metadata.
  • Improved the heuristic of setting the blend mode for transparent materials, resulting in fewer rendering artifacts in unreal.
  • Fixed a bug in which the UV coordinates for dirt maps were not exported to Datasmith.

360 VR

  • Polygon edges on static model street center lines and street node handles are now set to invisible by default on export.
  • Create 360 VR experiences with nondefault render settings using the 3D viewport render settings


  • Fixed a bug in which graph layers with names longer than 31 characters couldn't be exported to DXF.
  • The FBX importer now supports embedded textures on binary FBX files and applies opacity maps.
  • Fixed a bug in the FBX importer in which assets created by 3DS Max were sometimes wrongly composited.
  • The USD exporter now has an option to triangulate the exported meshes.
  • The SLPK exporter now handles transparent materials correctly; there are no more rendering artifacts in transparent materials when zooming out.

Procedural modeling language (CGA)

  • The new CityEngine CGA Material Encoder exports each material of a generated model to a folder containing a *.cgamat file and all used textures.
  • The new readMaterial function reads CGA material definitions (.cgamat files).
  • Added support for reading assets in the (.ifc) format. The structure of the elements in .ifc files is retained as much as possible and encoded in the group names.
  • The envelope, scatter, and splitArea operations now preserve groups; all CGA operations keep the group names and structure. This enables advanced visualization workflows, such as when working with .ifc files.
  • The new sortIndices and sortRowIndices functions allow you to sort elements in an array.
  • The new setElems function sets individual elements in an array.
  • Extended the string concatenation operator. You can now concatenate strings with arrays.
  • Fixed a wrong resulting scope translation for the envelope operation.
  • Fixed a rare crash in the split, trim, and insertAlongUV operations when face materials are present.

See the 2021.1 CGA changelog for a comprehensive list of changes and bug fixes.

CGA editor

  • Added the new Find Unused Declarations feature to the context menu which reports unused attributes, functions, const functions, and rules in the search view.

CGA compiler

  • Unused rules and functions are no longer written to the CGB. This reduces file size and maximizes compatibility with older procedural runtime versions.
  • Removed warnings for unused declarations. The new Find Unused Declarations option is available in the CGA Editor.
  • Fixed a bug in which nonmatching return types across styles were not detected on imports. This resulted in a crash when switching styles.
  • Fixed a bug that led to an unhandled error in rare cases when a recursive function was also defined in another style.

RPK creation

  • Fixed a bug in RPK creation in which asset search queries containing single quotes were not handled correctly in automatic asset detection.
  • Fixed a bug in which assets with uppercase file extensions were not handled correctly in automatic asset detection.


See the 2021.1 Python changelog for a comprehensive list of changes and bug fixes.



  • The Building_From_OpenStreetMap.cga rule now supports building parts and relations and uses the new OSM import design from this release.
  • The Urban rule is updated to version 1.3.0.


  • Fixed a bug in the Software Authorization component for RHEL 8 when using the Single Use license type. Note that support for RHEL 8 is still experimental in CityEngine 2021.1.