Random Tree Generation using 3D Vegetation Library

The 3D Vegetation Models Library from LumenRT is a very user friendly way of creating quick, realistic urban vegetation with a variety of plant species.

The library offers a large variety of trees (some of which I have never used). I wanted the CGA rule to create trees for my shapes at random, from a specified selection. A small alteration to the CGA code changes the default value.

For this example I used the Plant_Loader_with_LumenRT_Models.cga

The Plant_Loader_with_LumenRT_Models.cga uses the Name attribute to determine the file path of the model. The "Alder Buckthorn" model is used as a default. As seen below.

attr Name = 'Alder Buckthorn'

By changing the Name attribute to a conditional attribute, and setting a probability for specified plant models, the CGA rule will automatically assign models to shapes. In the example below, only 20 tree models were specified with a propablity of 5% each.

attr Name = 5%:"Alder Buckthorn" 5%:"American Chestnut" 5%:"American Sycamore" 5%:"Australian Pine" 5%:"Black Locust" 5%:"California Walnut" 5%:"Date Palm" 5%:"Ficus" 5%:"Field Elm" 5%:"Northern Red Oak" 5%:"Red Hickory" 5%:"Sassafras" 5%:"Southern Magnolia" 5%:"Strawberry Tree" 5%:"Sweetgum" 5%:"Umbrella Acacia" 5%:"White Ash" 5%:"White Oak" 5%:"White Poplar" else:"White Willow"

The resulting rule only assigns the models  that were specified as a default. Keeping the original @Range annotation in order to still be able to select any of the other available models.