About Creating a Dynamo Graph for Generative Design

You can use Dynamo to create graphs that are used as study types for Generative Design in Revit.

As a Dynamo author, you may need to work with a Revit designer to understand details about a particular design challenge, its goals, constraints, and other specifics. For a high-level description of the workflow, see Workflow: Generative Design.

If you are both a Revit designer and a Dynamo author, you can work alone. However, you may want to discuss your work with team members to make sure you have described the goals and its input and outputs appropriately.

To learn how to create graphs for Generative Design in Revit, examine the sample study types and see the Generative Design Primer.

While developing the Dynamo graph for Generative Design, follow these rules.

• Inputs and outputs have unique names.
• Inputs are set to "Is Input".
• Outputs are set to "Is Output".
• Additional requirements are satisfied. For complete details, see Generative Design Primer: Setting up a Graph.

In addition, you can use the following two nodes, which are installed in a custom package with Generative Design in Revit.

Data.Remember node

To ensure that Generative Design executes efficiently multiple times to generate different outcomes, Revit nodes are disabled. To use current data or generate new data related to a Revit model, use the Data.Remember node.

The Data.Remember node captures the output of any node and caches the results in the DYN file when the graph is saved. It can hold non-geometric data (strings and numbers) as well as geometry (such as solids, points, meshes, and surfaces) in a serialized format.

When you add nodes that have a dependency on a Revit Selected node, also add a Data.Remember node to hold the data. When the Generative Design tools panel is open during the authoring process, Dynamo indicates where a Data.Remember node is required. Click the + icon to add it. If the tools panel is closed, Dynamo performs this check when you create or update the study type.

See Generative Design Primer: Using Data from Revit and succeeding topics for information about Data.Remember node inputs, how to test Revit capture data, and current limitations.

Data.Gate node

The Data.Gate node controls the flow of data after the node. It activates the Create Revit Elements button on the Explore Outcomes dialog. In Generative Design, you click Create Revit Elements to run a branch of the graph after the Data.Gate node to integrate a selected outcome.

Use the Data.Gate node to control when a branch of the graph runs. This branch creates elements, such as adding desks to a room.

Using a graph with Generative Design in Revit

After creating and testing the graph in Dynamo for Revit, create the study type.

Then you can open Revit and click Manage tabGenerative Design panel Create Study, and select the folder. The graph appears as a study type in the Create Study dialog. Select the study type and proceed to define the study and explore outcomes.