Graph networks

CityEngine offers a suite of intuitive tools that allow you to create and edit graph networks. You can do the following with these tools:

  • Create graph networks with street creation tools.
  • Use the selection tool to select street nodes and edges. The selection displays in the Inspector, in which you can edit the attributes.
  • Modify graph segments and nodes using the transform tools.

Draw a street freehand

To draw a street freehand, click the Freehand Street Creation tool Freehand street creation tool or press Shift+G. You can also click Graph > Freehand Street Creation in the main menu.

Click and drag to start drawing a street and release when finished.

Draw a polygonal street

To draw a polygonal street, click the Polygonal Street Creation tool Polygonal Street Creation tool or press G. You can also click Graph > Polygonal Street Creation in the main menu.

Click to create the first vertex and click again to place additional vertices. To finish the street, double-click or press Enter.


The Polygonal Street Creation tool Polygonal Street Creation tool snaps to shape vertices and edges. Additionally, you can snap to guides and align segments parallel and perpendicular to them.

Tool options

The Tool Options window Tool options includes the following settings:

Tool optionsPolygonal Street Creation
Segment Length (m)

The length of the current street segment in meters.

  • Enter a value before or while drawing to lock the length. Press Enter to apply the value.
  • Lock and unlock the length by clicking either the lock ck Lolength or the unlock buttons Unlock length.

To open the Tool Options window Tool Options, click Window > Tool Options in the CityEngine main menu.

Street creation settings

You can configure the settings when creating new streets using the Street Creation Settings option. Click Graph > Street Creation Settings... from the main menu.

Settings include street width, block subdivision type, automatic graph cleanup, alignment to terrain, and model generation. Use presets to store a number of brushes, which are stored individually for each scene.

The following tables list the parameters:


Re-use settings from neighbors

If enabled, settings are copied from neighbor streets, if available. If an existing street is extended, settings are typically copied from that segment.

Apply graph cleanup

If enabled, the graph cleanup tool is executed after each editing operation. Note that the settings for graph cleanup can be controlled by clicking Graph > Cleanup Graph... from the main menu. See Cleanup Graph Networks.

Align terrain

If enabled, terrain layers are automatically aligned to new streets.


Street width

The street width.

Street center offset

The offset from the centerline of the street. The offset direction is perpendicular to the street direction.

Left sidewalk width

The left sidewalk width.

Right sidewalk width

The right sidewalk width.


The precision for shape creation.


Determines the approximate width for lanes. Used for the automatic setup of UV texture coordinates on dynamic street shapes.

See Street Parameters for more information.

Block generation

Subdivision type

The subdivision type for shape creation of new blocks.

See Block Parameters for more information.

Rule-based model generation

Rule file

If set, this rule file is assigned to all new street shapes.

Apply rule-based model generation

If enabled, model generation is automatically triggered.

Additional graph tools

CityEngine also includes additional tools to help with creating and editing streets, such as the Edit streets and curves, Cleanup streets, and Align streets to terrain tools.