CityEngineToolKit-GeodesignToolkit

A collection of Python scripts that integrate ArcGIS and CityEngine to enable data-driven, large-scale 3D urban design and scenario planning.

Summary

These tools streamline the preparation of GIS data for CityEngine procedural modeling. Instead of building full urban context models (aerial imagery, terrain, building footprints), they associate design content to individual features — streets, lots, blocks — that can be visualized as pop-ups in web maps or linked to web scenes. This approach enables large-scale geodesign workflows at a fraction of the normal preparation time.

Workflow Overview

1. Prepare geometry — Use the PrepareCE*Associations scripts to convert real-world GIS features into standardized, CityEngine-compatible geometries clustered at a single reference point.
2. Populate attributes — Use PopulateStreetParameters.py to add CityEngine street rule fields and default/randomized values.
3. Split by attribute — Use SplitFeaturebyAttribute.py to divide the attributed feature class into per-scenario layers.
4. Import into CityEngine — Import the prepared layers and apply procedural rules.
5. Batch export — Use the CityEngine scripts to export all layers as images, KML, FBX, or web scenes for sharing.

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ArcGIS Tools

PrepareCEStreetAssociations.py

Replaces polyline street geometries with standardized, north-south oriented lines located at the mean center of the input (or a reference) feature class. Output is projected to Web Mercator (EPSG:3857) for CityEngine compatibility.

Parameter	Type	Required	Description
inFeatureClass	Feature Class (Polyline)	Yes	Input street centerline feature class
outFeatureClass	Feature Class (Polyline)	Yes	Output path for the standardized geometry
StreetLength_LotArea	Double	Yes	Default street length in projection units (used if no size field is provided)
SizeField	Field (optional)	No	Field containing per-feature street lengths; overrides the constant if provided
referenceFeatureClassCentroid	Feature Class (optional)	No	Feature class whose mean center is used as the origin; defaults to the input's mean center

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PrepareCELotAssociations.py

Converts polygon lot features into uniform squares located at the mean center of the input (or reference) feature class. Side length is derived from the square root of the target area. Output is projected to Web Mercator (EPSG:3857).

Parameter	Type	Required	Description
inFeatureClass	Feature Class (Polygon)	Yes	Input lot polygon feature class
outFeatureClass	Feature Class (Polygon)	Yes	Output path for the simplified square geometries
StreetLength_LotArea	Double	Yes	Default lot area in projection units (used if no size field is provided)
SizeField	Field (optional)	No	Field containing per-feature lot areas; overrides the constant if provided
referenceFeatureClassCentroid	Feature Class (optional)	No	Feature class whose mean center is used as the origin; defaults to the input's mean center

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PrepareCEBlockAssociations.py

Creates a templated set of 7 polylines (a center street plus two flanking block outlines) per input feature, all anchored at the mean center of the input or reference feature class. Enables simultaneous exploration of transportation and land-use scenarios in CityEngine. Output is projected to Web Mercator (EPSG:3857).

Parameter	Type	Required	Description
inFeatureClass	Feature Class (Polyline)	Yes	Input street centerline feature class
outFeatureClass	Feature Class (Polyline)	Yes	Output path for the block geometry set
StreetLength_LotArea	Double	Yes	Default street segment length in projection units
SizeField	Field (optional)	No	Field containing per-feature street lengths; overrides the constant if provided
BlockWidth	Double	Yes	Width of the flanking block polygons on each side of the center street (projection units)
referenceFeatureClassCentroid	Feature Class (optional)	No	Feature class whose mean center is used as the origin; defaults to the input's mean center

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PopulateStreetParameters.py

Adds CityEngine street shape parameter fields and Complete Street Rule attribute fields to an existing feature class, then optionally populates them with default or randomized values. Used to prepare a GIS dataset to directly drive CityEngine street procedural rules.

Parameter	Type	Required	Description
in_feature_class	Feature Class	Yes	Target feature class to receive street parameter fields
add_cs_rule_attributes	Boolean	Yes	If True, adds all Complete Street Rule attribute fields (bike lanes, parking, transit, sidewalk amenities, etc.)
create_default_parameters	Boolean	Yes	If True, populates all street parameter fields with randomized plausible default values
create_random_attr	Boolean	Yes	If True (and add_cs_rule_attributes is also True), populates Complete Street Rule fields with randomized values

Street Shape Parameter Fields Added

Field Name	Type	Description
streetWidth	Double	Total carriageway width (meters)
streetOffset	Double	Lateral offset of street centerline
sidewalkWidthRight	Double	Right sidewalk width (meters)
sidewalkWidthLeft	Double	Left sidewalk width (meters)
precision	Double	Geometry precision value
laneWidth	Double	Width of a single travel lane (meters)
type	Text	Intersection type (e.g., "Crossing")
cornerStyle	Text	Corner geometry style (e.g., "Arcs")

Complete Street Rule Attribute Fields Added (when add_cs_rule_attributes = True)

Field Name	Type	Section
Lane_Distribution	Double	Lane configuration
Lane_Width	Double	Lane configuration
Speed_Limit_in_MPH	Double	Lane configuration
Stop_Begin / Stop_End	Text	Intersection markings
Crosswalk_Begin / Crosswalk_End	Text	Crosswalk markings
Begin_Crosswalk_To_Stop_Bar / End_Crosswalk_To_Stop_Bar	Double	Crosswalk geometry
Crosswalk_Width	Double	Crosswalk geometry
Right_Parking_Type / Left_Parking_Type	Text	Parking
Right_Parking_Width / Left_Parking_Width	Double	Parking
Center_Type	Text	Median/center treatment
Center_Width	Double	Median/center treatment
Planting_and_Walkway_Layout	Text	Median planting
Boulevard_Inside_Width / Boulevard_Configuration	Double / Text	Boulevard configuration
Median_Ground_Cover / Median_Planting_Length	Text / Double	Median planting
Median_Bus_Stop / Median_Bus_Stop_Location	Text	Median transit
Transit_Lane / Transit_Lane_Sides / Transit_Lane_Width / Transit_Lane_Position	Text / Double	Transit lanes
Right_Bike_Lane_Width / Left_Bike_Lane_Width	Double	Bike infrastructure
Right_Buffer_Width / Left_Buffer_Width	Double	Bike infrastructure
Buffer_Type / Buffer_Protection / Parking_Protection	Text	Bike infrastructure
Left_Bike_Box / Right_Bike_Box / Bike_Box_Color_Override	Text	Bike boxes
Sidewalk_Ground_Cover	Text	Sidewalk
Sidewalk_Planting_Width / Sidewalk_Planting_Length / Sidewalk_Planting_Spacing	Double	Sidewalk planting
Sidewalk_Bus_Stop / Sidewalk_Bus_Stop_Location	Text	Sidewalk transit
Sidewalk_Benches / Parking_Meters / Sidewalk_Street_Lamps / Traffic_Lights	Text	Sidewalk furniture
Bridge_Display	Text	Bridge

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SplitFeaturebyAttribute.py

Splits a single feature class into multiple feature classes, one per unique value of a chosen field. Useful for separating a batch-prepared CityEngine dataset into per-scenario or per-type layers before import.

Parameter	Type	Required	Description
inFeatureClass	Feature Class	Yes	Input feature class to split
outWorkSpace	Workspace (GDB or folder)	Yes	Destination workspace for the output feature classes
uniqueField	Field	Yes	Field whose unique values define the split; each unique value produces one output feature class
compactWorkspace	Boolean	Yes	If True, runs Compact_management on the output workspace after splitting

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CityEngine Tools

CEBatchLayerWebSceneExport.py

Iterates through all layers in the open CityEngine scene and exports each as a CityEngine Web Scene (.3ws) to a configurable output folder. Skips Panorama and Scene Light layers.

Configuration variables (edit at top of script before running):

Variable	Default	Description
outputFolder	"/BatchExport"	Output subfolder under the project's models/ directory
generateBoolean	False	If True, regenerates procedural models before export
deleteBoolean	False	If True, deletes each layer from the scene after export

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CEBatchLayerKMLExport.py

Iterates through all layers in the open CityEngine scene and exports each as a KML file to a configurable output folder. Terrain is set to TERRAIN_NONE.

Configuration variables (edit at top of script before running):

Variable	Default	Description
outputFolder	"/BatchExportKML/"	Output subfolder under the project's models/ directory
generateBoolean	False	If True, regenerates procedural models before export
deleteBoolean	False	If True, deletes each layer from the scene after export

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CEBatchLayerFBXExport.py

Iterates through all layers in the open CityEngine scene and exports each as an FBX file suitable for game engine import.

Configuration variables (edit at top of script before running):

Variable	Default	Description
outputFolder	"/BatchExportFBX"	Output subfolder under the project's models/ directory
generateBoolean	False	If True, regenerates procedural models before export
deleteBoolean	False	If True, deletes each layer from the scene after export
fileType	"BINARY"	FBX encoding; "BINARY" or "TEXT"
CollectTextures	True	Whether to bundle textures with the export
CreateShapeGroups	True	Whether to group shapes in the FBX hierarchy
IncludeMaterials	True	Whether to include material assignments
ExportGeometry	"MODEL_GEOMETRY_FALLBACK"	Geometry source: "MODEL_GEOMETRY_FALLBACK", "MODEL_GEOMETRY", or "SHAPE_GEOMETRY"

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CEBatchLayerImageExport.py

Iterates through all layers in the open CityEngine scene and captures a viewport snapshot of each layer as an image file.

Configuration variables (edit at top of script before running):

Variable	Default	Description
outputFolder	"\BatchExport/"	Output subfolder under the project's images/ directory
width	1920	Snapshot width in pixels
height	1080	Snapshot height in pixels
fileType	".png"	Output image format extension
turnOffAllLayers	True	If True, hides all layers before iterating so each snapshot shows only one layer
generateBoolean	False	If True, regenerates procedural models before each snapshot
deleteBoolean	False	If True, deletes each layer from the scene after export
iterateThroughBookMarksBoolean	False	If True, captures one snapshot per saved viewport bookmark per layer

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CESelectLayerByAttribute.py

Selects all layers in the open CityEngine scene that contain at least one object whose named attribute matches a target value. Useful for isolating a subset of layers before a batch operation.

Configuration variables (edit at top of script before running):

Variable	Default	Description
fieldName	"Crosswalk_End"	Name of the CityEngine object attribute to evaluate
fieldValue	"ladder"	Value to match against the attribute

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snapshotSelectedViewsheds.py (Esri Scripts/)

Captures viewport snapshots from the perspective of each selected viewshed, view dome, or view corridor analysis object. View domes produce 6 images covering all directions (front, left, back, right, up, down). Requires objects to be selected in the scene before running.

Configuration variables (edit at top of script before running):

Variable	Default	Description
hRes	1240	Output image resolution in pixels (square for 360 images; width for directional)
nameBase	"360 "	Prefix string prepended to all output image file names
ext	".png"	Output image format extension

Images are saved to the project's images/ directory. The camera is restored to its original state after each snapshot sequence.

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Limitations

• Cross-sectional attribute data for street centerlines is uncommon. Databases capturing lane counts, widths, and amenities per segment are still maturing.
• Batch procedural model generation requires QAQC review, especially for complex rule sets.
• CityEngine street width note: After mapping streetWidth to a street rule, changing the width requires updating both the shape parameter and the object attribute. See the Help documents for details.

For more detailed usage, see the HTML help documents in the Help/ directory.