Select objects

When you select objects with the Select tool Select tool, you identify the objects to which you want to apply an action or operation.

Click the Select tool Select tool or press Q. You can also click Select > Select Tool in the CityEngine main menu to open the tool.

  • You can select objects in the Viewport, Scene Editor or Select menu. When selecting objects in the viewport, they get highlighted in the Scene Editor as well and vice versa.
  • Selected objects are highlighted light blue / light grey.
  • Objects that are part of a layer that is locked or set invisible are not selectable.
  • Activating Isolation mode ( I ) and altering scene object type visibility (viewport menu) do not affect the current selection.
  • Map layers can be selected in the Scene Editor only.


  • To use the CityEngine tools, ensure the Tool Options window Tool options is open by clicking Window > Tool Options in the main menu.
  • Not all CityEngine tools have options under Tool Options.

Select in Viewport

The Select tool Select tool offers different methods to select objects:

Left click

Selects an individual object. On an already selected object components are selected (faces, edges, or vertices).

Double click

Selects and frames an individual object.

Left-to-right selection rectangle

Selects objects or components that are fully inside the selection rectangle. Map layers are not added to the selection.

Right-to-left selection rectangle

Selects objects that intersect with the selection rectangle. Map layers are not added to the selection.

These selection methods can be combined with modifiers:

Shift+left click

Add to existing selection.

Ctrl+left click

Deselects a selected or adds an unselected object to selection.

Ctrl+Shift+left click

Remove objects from an existing selection. Unselected objects are not added to the selection. This feature is especially handy when selecting using a selection box.

Right click in the Viewport offers a subset of selection methods that are described in the Select main menu.

Add or update selection sets

You can add, update, or edit selection sets for later use. To add or update a selection set, do the following:

  1. Select the shapes to add or update a selection set.
  2. Click the Add / Update Selection Set button Add/Update under Selection Sets in the Tool options Selection Tool options. You can also click Select > Add / Update Selection Set in the main menu.

    The Add / Update Selection Set window opens:

  3. To add or update an existing selection set, do one of the following:
    • Click Add to add and save the selection set.
    • Select an existing selection set in the list and click Update to update the selection.
  4. Click Cancel to close the window without adding or updating any selections sets.

To apply a saved selection set to shapes, do the following:

  1. Click the Choose... drop-down menu under Selection Sets in the Tool options Selection Tool options. You can also click Select > Apply Selection Set in the main menu.
  2. Click a saved selection set in the list.

    The selection is applied to the shapes.

You can rename, reorder, or remove an existing selection set by clicking Select > Edit Selection Sets... in the main menu, or click Edit Selection Sets... under Selection Sets in the Tool options Selection tool options.


  • Selection sets use an internal identifier to reference the selected objects. Therefore, previously created selection sets do not break when you rename objects.
  • When deleting a selection set the objects within don't get deleted.
  • When loading a selection set, objects that have been deleted in the meantime are ignored.

Tool options

The Tool options Selection Tool includes the following options:

Tool options Selection Tool
  • Select Select
  • Add to selection Add to selection (Shift)
  • Subtract from selection Subtract from selection (Shift+Ctrl)
  • Invert selection Invert selection (Ctrl)

Press and hold the modifiers in the parentheses to change the mode.

Disable Highlight

Hides the selection highlighting while the object remains selected. This is useful when modifying CGA attributes in the Inspector.

Selection Sets

Add, update, or edit a selection set.

Select in Scene Editor

The following options are available to perform selections in the Scene Editor:

Left click

  • On a layer / group layer: selects the layer, but does not select the scene objects inside.
  • On a scene object: selects individual object, deselects already selected objects.

Double click

  • On a layer / group layer: has no effect.
  • On a scene object: select and frame individual object.

Shift+left click

Add to selection, in lists: add adjacent objects.

Ctrl+left click

Deselects a selected or adds an unselected object to the selection.

Select main menu

The Select menu provides methods to grow a current selection you made in the Scene Editor or in the Viewport.

Select All, Deselect All, Invert Selection

  • In this case "All" means scene objects that are not locked and with visibility = true. Map layers are not included.
  • Select all and deselect all can also be triggered using the shortcuts Ctrl+A and Ctrl+Shift+A.
  • Invert the selection of all selected objects.

Select Objects in Same Layer

All objects in the same layer(s) are selected.

Select Objects by Map Layer

See May Layers for details.

Select Objects in Same Layer Group

All objects in the same layer group(s) are selected.

Select Objects of Same Type

Selects all objects with the same type(s) as the current selection.

Select Objects of Same Group

Selects all objects belonging to the same group as the objects in the source selection. For example, if the source selection contains a block, the resulting selection will contain the block and the block's shapes.

Select Objects with Same Rule File

Selects all objects having assigned a rule file that is present in the source selection.

Select Objects with Same Start Rule

Selects all objects having a start rule that is present in the source selection.

Select Continuous Graph Objects

This method can be used to select graph segments that are continuous, e.g. if they together define one street. The search for continued segments starts at the source selection.

Multi selections and lead selection

When you create multi selections, the highlighted color of the "lead selection" object varies from the color of the other selected objects. This is because the lead selection is used for operations where additional information is needed. For example the subtract tool uses the lead selection to determine whether object A shall be subtracted from B or B from A.

  • Typically the last object selected becomes the lead selection.
  • The lead selection is marked with a slightly brighter selection color.
  • To change the lead selection in an existing selection, use Shift+Click in the Viewport.

Isolate selection

When working with large scenes, it is often useful to hide objects temporarily in order to declutter the scene. Open the Visibility settings Visibility settings and click Isolate Selection or press I in the Viewport.

  1. Select the object to isolate.
  2. Click Isolate Selection (I) to remove all other models in the scene.

    Modify the isolated objects. You can also change the selection

  3. Click Isolate Selection (I) again to reveal all (according to visibility settings in the Scene Editor) models in the scene.
Isolate selection toggle button
Isolate selection in the Viewport