What Is a Policy?

Policies allow you to precisely define the behavior of each object in Parcel Editor and Road Editor during its expand. The expand is done from left to right. For instance, a parcel will be expanded before the mesh is placed on it.

You can access the policies by clicking directly on the object in the Layers window.

Select the policies to apply by clicking directly on the policy boxes in each object’s edit window in the Parcel and Road Editors.

Masking Policy

Each object has masking, which defines the 3D space needed by a object to fully expand.

The masking policy defines an object’s behavior during its expand.

• All or Nothing: This policy is applied to meshes by default. If the object’s mask cannot be fully expanded in the space available, the object is not expanded at all.
• Always Present: The object is always fully expanded.
• Cuttable: This policy is applied by default to textures. If the Cuttable policy is applied to an object, the object is clipped to fit into the available space.
• Transparent: This mask is applied by default to parcel links. If the Transparent policy is applied to an object, the object inherits the mask of its parent.

Please refer to Masking Policies for more detailed information on any of the policies.

Colliding Policy

The colliding policy defines how an object behaves in case of collision with another object.

• Not Solid: the objects are not taken into account to detect collision. This is the default policy.
• Variable: the objects with the higher colliding value stay intact. The other objects will be destroyed. If several objects share the same colliding value, the Editor will not take into account any collision between them.

For an example of the colliding policy in action, see Avoiding Collisions in Creating Filled Spaces with Rectangular Filler Policy.

Please see the Colliding Policies for further information and illustrations.

Existence Policy

Applying an existence policy to an object is an easy way to define how often an object exists and under what conditions.

For certain existence policies (String, Int, and Floating, you can add tags to define existence properties by clicking on the City Project Settings option in the toolbar, then on the Context Generator.

• Maybe: Object exists X percent of the time. X is an integer ranging from 1 to 100.
• Always: Default setting for all objects. The object will exist at each instance of parcel expansion in View Mode.
• String=: Object exists as function of a defined tag. The object will exist when string value in render mode is equal to a string value defined in City Project Settings.
• Int =: Object exists when object tag value, here defined as an integer, is equal to an assigned value.
• Int >: Object exists when object tag value, here defined as an integer, is greater than an assigned value.
• Int >=: Object exists when object tag value, here defined as an integer, is equal to or greater than an assigned value.
• Int <=: Object exists when object tag value, here defined as an integer, is equal to or less than an assigned value.
• Float: Object exists when object tag value, here defined as a decimal value, is equal to an assigned value.
• Float >: Object exists when object tag value, here defined as a decimal value, is greater than an assigned value.
• Float >= Object exists when object tag value, here defined as a decimal value, is greater than or equal to an assigned value.
• Float <=: Object exists when object tag value, here defined as a decimal value, is less than or equal to an assigned value.

Expanding Policy

Expanding policies control the expansion of objects in the parcel.

• Simple: The default expanding policy. No expanding rules are applied to the parcel in View Mode.
• Select: The parcel generator selects elements from a range of elements when it expands the parcel in View Mode.
• Rectangular Filler: The parcel generator uses child items of a parcel or subparcel to fill an enclosed space.

Positioning Policy

Positioning policies are used to describe how an object moves during parcel regeneration. Positioning policies can be combined with existence and masking policies for even more powerful operations.

• Cone Rotate: Rotates the object in 3D space around the Z-axis by a specified number of degrees.
• Follow Support: This is the positioning policy used for meshes that are stacked on top of each other. If you want one mesh to adopt the behavior of the mesh supporting it, you would use this policy.
• Planar Push: Displaces the object horizontally by a specified number of units.
• Positioning Policy: Default setting - no positioning policy selected when this choice is activated.
• Rotate Positioning: Rotates the object a specified number of degrees.
• Vertical Push: Displaces the object vertically by a specified number of units.
• Geometry Scale: Applies to sectors and allows them to regulate their expand within the defined space of the Sector Link in Parcel Editor. A Geometry Scale policy is required for Sector Links in order for them to expand correctly.