Autodesk FBX is a proprietary 3D geometry exchange format with a freely available SDK. It has gained popularity as the main exchange format for the Unreal and Unity game engines and related AR/VR applications. It currently lacks modern material support (for example, PBR) and metadata transport. For use cases in which AV/VR applications are not relevant, import using glTF instead.
In addition to the general export options, the following options are available for FBX export:
Create Shape Groups
If enabled, a transformation node is inserted for each shape (building). Meshes are not merged by material across shapes.
If enabled, textures are stored in the binary FBX file.
CGA mapping to FBX
As the FBX file format is verbose, selected examples are shown below. Refer to the Autodesk documentation for further information.
Geometry and transformation data
The subsections below contain examples of exporting CityEngine data to FBX in Autodesk Maya.
CityEngine geometry and transformation data
The pivot is in the origin; the scope (yellow) contains a translation and a rotation.
Exported FBX data in Autodesk Maya
The following screen capture shows an exported scene with FBX data in Autodesk Maya. Both One Mesh Per options have been disabled to avoid merging assets. In this case, each asset is parented to a transformation node. Otherwise, the transformation is applied to the vertices.
Multitexture and layered texture nodes
The CityEngine material model multiplies all color textures (color map and dirt map, if present) with the diffuse color. This example displays the layering and multiplication of a color map and a dirt map.
Exported FBX data inAutodesk Maya
For FBX data, CityEngine exports multiple textures as layered texture nodes whose blend modes are set to multiply.
Work with per-texture transformations
CityEngine features material attributes to scale and translates and rotates textures independently of the actual texture coordinates stored inside the assets:
Exported FBX to Autodesk Maya
Upon exporting FBX data into Autodesk Maya, the CityEngine tu and tv attributes are mapped to the Offset parameter of the Autodesk Maya place2dTexture nodes, su/sv are mapped to the RepeatUV parameter, and rw is mapped to the Rotate Frame parameter.