Preparing data for import

When using imported polygons as initial shapes for building generation, the following points should be considered when creating the source data in a third party application:

  • Polygons drawn counterclockwise result in shapes facing upwards. This is the desired orientation.
  • The first edge of a polygon is interpreted as the "front" of the generated building. This is useful when you would like to create different facades for the front, side and the back, of your building.

    Polygons edge orientation
    Polygons edge orientation
  • Depending on the file format, CityEngine interprets group, entity, or object names as names for start rules. Consequently, ensure to group your meshes and assign names that are valid CGA shape grammar identifiers (e.g. no special characters, space, etc.).
  • Some tools might have different units for exporting. Check the exported file in a text editor to see the actual dimensions. Consequently, most import wizards offer an option to apply a uniform scaling of the imported data.