RcBuildingCreateFromRoofPrint

Command Name	Icon	Menu Path
RcBuildingCreateFromRoofPrint		Not yet in menu (CLI only)

Overview

This command processes roof geometry for the 3D modeler.

Prerequisites

• Requires closed 3D roof curves.
• Input curves can be either attributed or raw geometry.

Attribute Management

• Building Grouping: If attributes are present, a common identifier (e.g., Building ID) is used to group multiple roof parts. This value is mapped to the BuildingID property in the modeler classes.
• Elevation (ZMin): An optional attribute can define the building's base altitude. If provided, generated Roofprint curves are set to this Z-value; otherwise, they are created at Z = 0.0.

Grouping for Raw Geometry

• If the input curves lack attributes, they must be pre-grouped. The command uses Rhino Group membership to identify building units.

Output Options

• Users can choose to either transform the original curves or duplicate them to create new entities compatible with the 3D modeler.

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Workflow

Step 1: Initial Options

When launching the command, the first prompt defines the generation logic:

• RoofPrintLayer: Select the source layer (e.g., 'Roofs1').
• ComputeConstrId (yes/no): Initialize the ConstrID attribute. Recommended: yes.
• OriginalCurves (duplicate/modify): Duplicate preserves source geometry.

Step 2: Attribute Mapping

The second prompt defines the data structure:

• BuildingID: Grouping attribute (e.g., 'id'). Falls back to Rhino Groups if undefined.
• ZMin: Elevation attribute (e.g., 'r_zminid'). Created at Z=0.0 if undefined.

Step 3: Execution & Selection

1. Review the summary displayed in the command line.
2. Select curves:curves: Pick specific curves or hit [Enter] to process all objects.

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Example

In this example, we use roof curves from a Shapefile (3D Polygons) in the 'Roof1' class.

Upon launch, the command line displays:

Options (RoofPrintLayer=nolayer ComputeConstrId=true OriginalCurves=duplicate):

By clicking on the RoofprintLayer option, we select the “Roofs1” layer

Confirm our choices with [Enter]

The command line now displays:

Define the potential attributes (BuildingID=undefined ZMin=undefined):

By clicking on ‘BuildingID’, we select the ‘id’ attribute of the ‘Roof1’ class

Attribute to be used as “BuildingID” (CityObject FaceType FileName LODC RootNodeNa Type id r_zminid):

The command line changes to:

Define the potential attributes (BuildingID =id ZMin =missing):

By clicking on ‘ZMin’, we select the ‘r_zminid’ attribute from the ‘Roof1’ class.

Confirm our selections with [Enter]

Upon launch, confirm your choices with [Enter]. The CLI displays the selection details:

• layer containing the roof curves: 'Roofs1' • use attribute 'id' as a 'BuildingID' • use attribute 'r_zminid' to fix the Z of the Footprint curves

Next, select the curves and press [Enter]. The command line displays the final summary:

• feature class "Roofprint" created ✔ • feature class "Building" created ✔ • load 2 feature classes: "Building", "Roofprint" loaded • "Building", "Roofprint" objects stored • 141 feature class "Building" items prepared • 1930 feature class "Roofprint" items prepared

The system confirms success:

(ツ) you can now use the RcBuildingModelerModelize command to create 3D buildings!

Here is the result after modelling