CUBIZEN: Global Mapper, CityEngine & Creative Tech

When working on complex urban models in Esri CityEngine, you might have wondered: "Is it possible to get statistics on the number of buildings, the area per land use, or the total count of windows in real time?"

The answer is yes. By using the report command in your CGA rules, you can display live information in the Reports tab of the Inspector panel. This data can then be easily copied into a spreadsheet for detailed analysis and reporting.

The Core Concept of the Report Command

The fundamental idea behind the report function is to instruct CityEngine to record specific information at a chosen stage of your rule hierarchy. Even if you are a beginner at CGA, you will find this command easy to implement as you progress in your coding journey.

In the following example, we will create a simple building rule that automatically tracks floor count and gross floor area during model generation.

Let's start with a simple example: extracting information about the number of floors and the Gross Floor Area (GFA).

@Range(min=1, max=10, stepsize=1)
attr floor = 1

Lot --> extrude(floor * 3) BD

BD --> split(y) { ~3: Floor }*

Floor -->
    report("Floor Count", 1) 
    report("Gross Floor Area", geometry.area())
    X.

Rule Explanation:

• The model extrudes the Lot based on the floor attribute and then splits the volume into 3-meter segments.
• Every time the Floor rule is triggered, the report command adds 1 to the "Floor Count."
• It also calculates the current polygon's area using geometry.area() and adds it to the "Gross Floor Area" total.
• The geometry.area() function returns the current polygon surface area being processed by the rule.

As you adjust the attributes in the Inspector panel, these values will update instantly. Watch the video below to see how the reports respond to real-time changes.

Generated values appear inside the Reports tab located in the Inspector panel.

Grouping Statistics by Land Use

For more advanced urban planning scenarios, you might need to categorize statistics by land use. By using string concatenation in the report label, you can generate grouped data automatically.

@Range(min=1, max=10, stepsize=1)
attr floor = 1
attr Landuse = "Residential" # Example attribute

Lot -->
    report("Building Count." + Landuse, 1)
    report("Footprint Area." + Landuse, geometry.area())
    extrude(floor * 3) BD

BD --> split(y) { 3: Floor }*

Floor -->
    report("Floor Count." + Landuse, 1)
    report("Total Area." + Landuse, geometry.area())
    X.

In this example, the statistics are appended with the value of the Landuse attribute. If you have multiple buildings with different land uses selected, CityEngine will aggregate the data for each category separately. This allows you to quickly see the total area for "Commercial" versus "Residential" zones.

While numerical reports are powerful for precision, they can sometimes be difficult to interpret visually. To address this, CityEngine Dashboard tools allow procedural report data to be visualized as charts, graphs, and live analytics dashboards.

In the next lesson, we will learn how to visualize this data effectively.