Simulation 3D Message Set

Send data to Unreal Engine visualization environment

Since R2025a

• 

Libraries:
Vehicle Dynamics Blockset / Vehicle Scenarios / Sim3D / Sim3D Core
Aerospace Blockset / Animation / Simulation 3D
Simulink 3D Animation / Simulation 3D / Utilities

Description

The Simulation 3D Message Set block sends data to the Unreal Engine^® 3D visualization environment. In your model, ensure that the Simulation 3D Scene Configuration block is at the same level as the Simulation 3D Message Set block.

Tip

Verify that the Simulation 3D Message Set block executes before the Simulation 3D Scene Configuration block. That way, Simulation 3D Message Set prepares the signal data before the Unreal Engine 3D visualization environment receives it. To check the block execution order, right-click the blocks and select Properties. On the General tab, confirm these Priority settings:

• Simulation 3D Scene Configuration — 0

• Simulation 3D Message Set — -1

For more information about execution order, see Control and Display Execution Order (Simulink).

Configure Scenes to Receive Data

To use the block, you must configure scenes in the Unreal Engine environment to receive data from the Simulink^® model:

1. Install the Customize Scenes in Unreal Engine for 3D Simulations.

2. In the Unreal^® Editor, follow these general workflows to receive data from Simulink. For detailed information, see Get Started Communicating with the Unreal Engine Visualization Environment.

   Unreal Engine User	Workflow
   Blueprint	Instantiate the Sim3DGet actor that corresponds to the data type you want to receive from the Simulink model. This example shows the Unreal Editor Sim3DGet data types. Specify an actor tag name that matches the Simulation 3D Message Set block Signal name parameter. Navigate to the Level Blueprint. Find the blueprint method for the Sim3DGet actor class based on the data type and size that you want to receive from the Simulink model. For example, in Unreal Editor, this diagram shows that Read Scalar Integer is the method for Sim3DGetInteger actor class to receive int32 data type of size scalar. Compile and save the scene. Note By default, the Double Lane Change scene has a Sim3DGetInteger actor with tag name TrafficLight1.
   C++ class	Create a new actor class for the mesh or asset that you want the Simulink model to interact with. Derive it from ASim3dActor. In the new actor class: Declare a pointer to the signal name as a class field. Get the class tag. Create a signal reader and assign the pointer in the method Sim3dSetup. In the method Sim3dStep, invoke the ReadSimulation3DMessage function to read the data from a Simulink model. Delete the signal reader in the method Sim3dRelease of the actor.

   For more information about the Unreal Editor, see the Unreal Engine Documentation.

Ports

Input

WriteMsg — Data sent to scene

scalar | array

Data sent to the 3D visualization environment scene. In the Unreal Engine environment, you can configure the Sim3DGet class to receive the data from the Simulink model.

Parameters

Signal name, SigName — Message signal name

mySignal (default)

Specifies the signal name in the 3D visualization environment. In the Unreal Engine environment, use the Sim3Get actor class 'Tags' property located in the 'Details' pane.

For example, you can send data to the double lane change scene that changes the traffic signal light color to red, yellow, or green. To send data to the traffic signal light, set this parameter to TrafficLight1. In the double lane change scene, the 'Tags' property value for Sim3dGetInteger actor class is set to TrafficLight1.

Sample time — Sample time

0.02 (default) | -1 | scalar

Sample time, in s. The graphics frame rate is the inverse of the sample time. If you set the sample time to -1, the block uses the sample time specified in the Simulation 3D Scene Configuration block.

Version History

Introduced in R2025a