Trees and foliage tutorial

 

Preparations

Take the following steps as preparation for following this tutorial:

• Start the Demo Heat Stress Project.

Tree and foliage data in general

There are a number of use-cases in which having accurate green data is relevant. In urban development, green is become more and more of a required spatial aspect. But also for topics like biodiversity and heat stress the impact of the presence of green is significant. It is therefor important to have as accurate data as possible related to the presence of green in an urban environment for a variety of simulation use-cases.

For this tutorial, there will be a focus on using trees and foliage data with and for the Heat Overlay, but the principles translate over to other use-cases as well.

Preparation

Downloading trees data from the Project

In the ribbon, ensure the "Current Situation" is selected.

In the "Buildings" dropdown, select "Export Geo Data".

In the popup that appears, its possible to indicate which Buildings data specifically needs to be exported.

Opt to export Buildings with a specific Attribute by checking the "With Attribute" option.

As Attribute, select the Attribute FOLIAGE_CROWN_FACTOR. This is an Attribute which is only associated with trees.

Opt to check for the value of the Attribute, by t=checking the "With Value" option as well.

Ensure the value check is set to X > 0. This will only export Buildings which have a FOLIAGE_CROWN_FACTOR of more than 0.

Find the export option "Download GeoJSON File", and click on "Export File".

Place the file somewhere on your computer where you will be able to find it again later.

The resulting GeoJSON file is one which contains all the trees from the Project.

Removing existing trees from the Project

Before new trees data can be imported, the existing trees data should be removed. Otherwise, the original data may persist together with the new to-be-imported data, and throw off the results of calculations relying on the trees.

In the ribbon, ensure the "Current Situation" is selected.

In the "Buildings" dropdown, select "Select Multiple Buildings".

In the bottom panel, an interface now allows for the mass-manipulation of multiple Buildings at the same time, based on Function and extent.

As category, select "Specific Function".

As Function, select "Default Decidiuous Trees". This is the default type of trees and means this operation will only affect trees.

As action, select "REMOVE"

Click on "Entire Map"

A prompt will appear. Confirming it will delete the 160 or so trees from the Project, leaving it without any trees data.

Clearing the Heat Overlay

Finally, it is necessary to ensure the Heat Overlay now operates from a basis where it does not have any foliage information, so that the results of importing data can be verified.

In the ribbon, ensure the "Current Situation" is selected.

Click on "Overlays", so the list of Overlays appears in the [[left panel].

Select the "PE Temperature" Overlay.

In the right panel, click on "Configuration Wizard". This opens the Heat Overlay Wizard.

Continue to the step regarding Foliage.

Opt to use "Tree Functions" height and foliage crown factor.

Close the Configuration Wizard.

Click on "Update now" in the right panel to force the Overlay to recalculate.

Notice the results for the entire Project are now significantly hot. This is because there is now no foliage data for the Heat Overlay to work with.

Importing trees data

In the ribbon, ensure the "Current Situation" is selected.

In the "Buildings" dropdown, select "Import Geo Data". This opens the Geo Data Wizard.

As import method, select "GeoJSON file".

As GeoJSON file, click on "select local file". Select the previously downloaded trees geojson file.

Take note of the "View features" step, where the locations of all trees are shown.

Also take note of the "buffer size" slider. when the dataset consists of points, all points will be buffered with the size indicated by the slider. By default all such points end up as polygons of exactly 1m² in size. Any polygons in the dataset will remain as-is.

Skip through the step for filtering features (all features are desired), adding or updating features (the default is to add, which is what we nat to do), and the naming scheme (names are not relevant for calculations).

In the "Select Attributes" step, take note of the Attribute FLOOR_HEIGHT_M. This Attribute determines the height of the trees which are imported. If the dataset of trees has a different Attribute which indicates the tree height of features, find that Attribute in the list of [[Attribute] names, and then edit the name of the Attribute as it is imported using the text input fields in the middle of the screen.

In the "Assign Functions" step, keep "One Function" selected, and click on "Select" to select the default function.

Select "Default Decidiuous Trees", and continue to the next step.

For the "Owner", select the Municipality.

Continue to the last step of the Wizard and click on "Finalize" to add the data to the Project.

Tutorial completed

Congratulations. You have now completed this tutorial. In it, you have learned how to import trees and foliage data, with an emphasis for use with the Heat Overlay..