Simulation 3D Scene Configuration

Scene configuration for 3D simulation environment

Since R2020b

• 

×

Libraries:
Offroad Autonomy Library / Simulation 3D
Aerospace Blockset / Animation / Simulation 3D
Automated Driving Toolbox / Simulation 3D
Robotics System Toolbox / Simulation 3D
Simulink 3D Animation / Simulation 3D / Environment
UAV Toolbox / Simulation 3D
Vehicle Dynamics Blockset / Vehicle Scenarios / Sim3D / Sim3D Core

Description

Note

Simulating models with the Simulation 3D Scene Configuration block requires Simulink^® 3D Animation™.

The Simulation 3D Scene Configuration block implements a 3D simulation environment that is rendered by using the Unreal Engine^® from Epic Games^®. UAV Toolbox integrates the 3D simulation environment with Simulink so that you can query the world around the vehicle and virtually test perception, control, and planning algorithms. Using this block, you can also control the position of the sun and the weather conditions of a scene. For more details, see Sun Position and Weather.

You can simulate from a set of prebuilt scenes or from your own custom scenes. Scene customization requires the UAV Toolbox Interface for Unreal Engine Projects support package. For more details, see Customize Unreal Engine Scenes for UAVs.

You can also simulate custom scenes designed and built in RoadRunner. To do so, you must first export scenes from RoadRunner and specify the path to the exported scene artifacts in the Project parameter of the Simulation 3D Scene Configuration block.

Tip

The Simulation 3D Scene Configuration block must execute after blocks that send data to the 3D environment and before blocks that receive data from the 3D environment. To verify the execution order of such blocks, right-click the blocks and select Properties. Then, on the General tab, confirm these Priority settings:

• For blocks that send data to the 3D environment, Priority must be set to -1. That way, these blocks prepare their data before the 3D environment receives it.

• For the Simulation 3D Scene Configuration block in your model, Priority must be set to 0.

• For blocks that receive data from the 3D environment, Priority must be set to 1. That way, the 3D environment can prepare the data before these blocks receive it.

For more information about execution order, see How Unreal Engine Simulation for UAVs Works.

Examples

Simulate Simple Flight Scenario and Sensor in Unreal Engine Environment

Visualize sensors in a simulation environment that uses Unreal Engine® from Epic Games®.

• Open Live Script

Depth and Semantic Segmentation Visualization Using Unreal Engine Simulation

Visualize depth and semantic segmentation data captured from a camera sensor in a simulation environment. This environment is rendered using the Unreal Engine® from Epic Games®.

• Open Live Script

Parameters

Scene

Scene Selection

Scene source — Source of scene

Default Scenes (default) | RoadRunner | Unreal Executable | Unreal Editor

Source of the scene in which to simulate, specified as one of the options in the table.

Option	Description
Default Scenes	Simulate in one of the default, prebuilt scenes specified in the Scene name parameter.
RoadRunner	Simulate in a RoadRunner scene. To import the scene, specify the RoadRunner file in the Project parameter.
Unreal Executable	Simulate in a scene that is part of an Unreal Engine executable file. Specify the executable file in the Project name parameter. Specify the scene in the Scene parameter. Select this option to simulate in custom scenes that have been packaged into an executable for faster simulation.
Unreal Editor	Simulate in a scene that is part of an Unreal Engine project (.uproject) file and is open in the Unreal® Editor. Specify the project file in the Project parameter. Select this option when developing custom scenes. By clicking Open Unreal Editor, you can co-simulate within Simulink and the Unreal Editor and modify your scenes based on the simulation results.

Scene name — Name of prebuilt 3D scene

US city block | Suburban scene

Name of the prebuilt 3D scene in which to simulate, specified as one of these options. For details about a scene, see its listed corresponding reference page.

• US city block – US City Block

• Suburban scene – Suburban scene

Dependencies

To enable this parameter, set Scene source to Default Scenes.

Project name — Name of Unreal Engine executable file

VehicleSimulation.exe (default) | valid executable file name

Name of the Unreal Engine executable file, specified as a valid executable project file name. You can either browse for the file or specify the full path to the project file, using backslashes. To specify a scene from this file to simulate in, use the Scene parameter.

By default, Project name is set to VehicleSimulation.exe, which is on the MATLAB^® search path.

Note

If you select a custom Unreal executable file built with a version of Unreal Engine that is not compatible with the current version of MATLAB, you receive one of these error messages:

• "Incompatible version of 3D Simulation engine: Undefined": For Unreal executable built for a MATLAB release prior to R2023b

• "Incompatible version of 3D Simulation engine: 23.2.0": For Unreal executable built for MATLAB R2023b or later

To resolve these errors, you must migrate the Unreal project and rebuild the executable with the latest support package installed. For more information, see .

Example: C:\Local\WindowsNoEditor\AutoVrtlEnv.exe

Dependencies

To enable this parameter, set Scene source to Unreal Executable.

Project — Name of Unreal Engine project file or RoadRunner file

valid project file name

Name of the Unreal Engine project file or RoadRunner file, specified as a valid project file name. You can either browse for the file or specify the full path to the file, using backslashes. The file name must contain no spaces.

To simulate scenes from Unreal Engine project file in the Unreal Editor, click Open Unreal Editor. If you have an Unreal Editor session open already, then this button is disabled.

To run the simulation, in Simulink, click Run. Before you click Play in the Unreal Editor, wait until the Diagnostic Viewer window displays this confirmation message:

In the Simulation 3D Scene Configuration block, you set the scene source to 'Unreal Editor'.
In Unreal Editor, select 'Play' to view the scene.

This message confirms that Simulink has instantiated the scene actors, including the vehicles and cameras, in the Unreal Engine 3D environment. If you click Play before the Diagnostic Viewer window displays this confirmation message, Simulink might not instantiate the actors in the Unreal Editor.

To simulate a RoadRunner scene, browse for the folder containing the exported RoadRunner scene files, then specify the Filmbox (.fbx) file.

Dependencies

Scene Parameters

Scene view — Placement of virtual camera that displays scene

Custom | Scene Origin | vehicle name

Configure the placement of the virtual camera that displays the scene during simulation.

• If your model contains no vehicle blocks, then during simulation, you view the scene in free camera mode from a camera positioned at the scene origin. The camera movement uses the Z-up left-handed (LH) Cartesian coordinate system. To change the view to a custom viewpoint, set Scene view to Custom. Then, set the Initial viewer translation and Initial viewer rotation values to view the scene in free camera mode at the specified viewpoint.

• If your model contains at least one vehicle block, then by default, you view the scene from a camera attached to the first vehicle that was placed in your model. To change the view to a different vehicle, set Scene view to the name of that vehicle. The Scene view parameter list is populated with all the Name parameter values of the vehicle blocks contained in your model.

If you add a Simulation 3D Scene Configuration block to your model before adding any vehicle blocks, the virtual camera remains positioned at the scene origin. To reposition the camera to follow a vehicle, update this parameter.

Scene Controls

When Scene view is set to Scene Origin or Custom, you can change the location of the camera to navigate in the scene during simulation using keyboard and mouse control. You can also change the camera location when the simulation is paused.

To navigate in the 3D environment, use these keyboard shortcuts.

Keyboard Shortcut	Camera Control
W	Move forward.
Shift+W	Move faster in the forward direction.
S	Move backward.
Shift+S	Move faster in reverse direction.
A	Move left.
Shift+A	Move faster toward left.
D	Move right.
Shift+D	Move faster toward right.
Q	Move up.
Shift+Q	Move faster in the upward direction.
E	Move down.
Shift+E	Move faster in the downward direction.
Mouse scroll wheel	Control the camera distance from the cursor point.
Shift+mouse scroll wheel	Camera moves faster.
Mouse right-click and drag	Orbit around the cursor point.
O	Attach camera to actor under the cursor point.
Mouse left-click and drag	Orbit around the actor after camera attaches to the actor.
P	Detach camera from the actor.
L	Record the current viewpoint and display Location saved on the scene.
1 to 9	Access the stored viewpoints, if available.
Tab	Cycle the view between all vehicles in the scene and the viewpoint at the start of the simulation, in the forward direction.
Shift+Tab	Cycle the view between all vehicles in the scene and the viewpoint at the start of the simulation, in the reverse direction.
I	Display the keyboard shortcuts on the screen.

Vehicle Views

When Scene view is set to a vehicle name, during simulation, you can change the location of the camera around the vehicle. You can also set the view to a vehicle during simulation by pressing Tab.

To smoothly change the camera views, use these keyboard shortcuts.

Keyboard Shortcut	Camera View
1	Back left	View Animated GIF
2	Back
3	Back right
4	Left
5	Internal
6	Right
7	Front left
8	Front
9	Front right
0	Overhead

For additional camera controls, use these keyboard shortcuts.

Keyboard Shortcut	Camera Control
Tab	Cycle the view between all vehicles in the scene.  View Animated GIF
Mouse scroll wheel	Control the camera distance from the vehicle.  View Animated GIF
L	Toggle a camera lag effect on or off. When you enable the lag effect, the camera view includes: Position lag, based on the vehicle translational acceleration Rotation lag, based on the vehicle rotational velocity This lag improves visualization of overall vehicle acceleration and rotation.  View Animated GIF
F	Toggle the free camera mode on or off. When you enable the free camera mode, you can use the mouse to change the pitch and yaw of the camera. This mode allows you to orbit the camera around the vehicle.  View Animated GIF

Sample time — Sample time of visualization engine

1/60 (default) | real positive scalar

Sample time, T_s, of the visualization engine, specified as a real positive scalar. Units are in seconds.

The graphics frame rate of the visualization engine is the inverse of the sample time. For example, if Sample time is 1/60, then the visualization engine solver tries to achieve a frame rate of 60 frames per second. However, the real-time graphics frame rate is often lower due to factors such as graphics card performance and model complexity.

By default, blocks that receive data from the visualization engine inherit this sample rate.

Display 3D simulation window — Unreal Engine visualization

on (default) | off

Select whether to run simulations in the 3D visualization environment without visualizing the results, that is, in headless mode.

Consider running in headless mode in these cases:

• You want to run multiple 3D simulations in parallel to test models in different Unreal Engine scenarios.

Dependencies

To enable this parameter, set Scene source to Default Scenes or Unreal Executable.

Weather

Override scene weather — Option to control the scene weather and sun position

off (default) | on

Select whether to control the scene weather and sun position during simulation. Use the enabled parameters to change the sun position, clouds, fog, rain, and snow.

This table summarizes sun position settings for specific times of day.

Time of Day	Settings	Unreal Editor Environment
Midnight	Sun altitude: -90 Sun azimuth: 180
Sunrise in the north	Sun altitude: 0 Sun azimuth: 180
Noon	Sun altitude: 90 Sun azimuth: 180

This table summarizes settings for specific cloud conditions.

Cloud Condition	Settings	Unreal Editor Environment
Clear	Cloud opacity: 0
Heavy	Cloud opacity: 85
Heavy	Enable Volumetric clouds: Selected Cloud Coverage: 50 Cloud layer altitude: 6

This table summarizes settings for specific fog conditions.

Fog Condition	Settings	Unreal Editor Environment
None	Fog density: 0
Heavy	Fog density: 100

This table summarizes settings for specific rain conditions.

Rain Condition	Settings	Unreal Editor Environment
Light	Cloud opacity: 10 Rain density: 25
Heavy	Cloud opacity: 10 Rain density: 80

This table summarizes settings for specific snow conditions.

Snow Condition	Settings	Unreal Editor Environment
Heavy	Snow density: 50

Sun

Sun azimuth — Azimuth angle from south to horizontal projection of the sun ray

90 (default) | any value between 0 and 360

Azimuth angle in the horizontal plane measured from the south to the horizontal projection of the sun rays, in deg.

Use the Sun altitude and Sun azimuth parameters to control the time of day in the scene. For example, to specify sunrise in the north, set Sun altitude to 0 deg and Sun azimuth to 180 deg.

Dependencies

To enable this parameter, select Override scene weather.

Sun altitude — Altitude angle between sun and horizon

40 (default) | any value between -90 and 90

Altitude angle in a vertical plane between the sun's rays and the horizontal projection of the rays, in deg.

Use the Sun altitude and Sun azimuth parameters to control the time of day in the scene. For example, to specify sunrise in the north, set Sun altitude to 0 deg and Sun azimuth to 180 deg.

Dependencies

To enable this parameter, select Override scene weather.

Enable geospatial sun — Option to enable geospatial sun

off (default) | on

Select this check box to enable geospatial sun. Enabling geospatial sun is useful to simulate conditions near the poles or at locations with disproportionate lengths of day versus night.

Dependencies

To enable this parameter, select Override scene weather.

Latitude — Latitude of geolocation on earth

0 (default) | scalar

Latitude of geolocation on earth, specified as a scalar, in deg.

Dependencies

To enable this parameter, select Override scene weather and Enable geospatial sun.

Longitude — Longitude of geolocation on earth

0 (default) | scalar

Longitude of geolocation on earth, specified as a scalar, in deg.

Dependencies

To enable this parameter, select Override scene weather and Enable geospatial sun.

Date (YYYY-MM-DD) — Date

2023-01-01 (default) | integer

Date, specified as an integer in the format YYYY-MM-DD.

Dependencies

To enable this parameter, select Override scene weather and Enable geospatial sun.

Time (HH:MM:SS) — Time

10:30:00 (default) | integer

Time, specified as an integer in the format HH:MM:SS.

Dependencies

To enable this parameter, select Override scene weather and Enable geospatial sun.

Time zone — Time zone

-5.0 (default) | any value between -12.0 and 12.0

Time zone specifies the number of hours offset from the Coordinated Universal Time (UTC) or Greenwich Mean Time (GMT).

Dependencies

To enable this parameter, select Override scene weather and Enable geospatial sun.

Daylight saving time — Option to enable daylight saving time

off (default) | on

Select this check box to enable daylight saving time.

Dependencies

To enable this parameter, select Override scene weather and Enable geospatial sun.

Cloud

Cloud speed — Unreal Editor Cloud Speed global actor target value

1 (default) | any value between -100 and 100

Parameter that corresponds to the Unreal Editor Cloud Speed global actor target value. The clouds move from west to east for positive values and east to west for negative values.

Use the Cloud opacity and Cloud speed parameters to control clouds in the scene.

Dependencies

To enable this parameter, select Override scene weather.

Cloud opacity — Unreal Editor Cloud Opacity global actor target value

10 (default) | any value between 0 and 100

Parameter that corresponds to the Unreal Editor Cloud Opacity global actor target value, in percent. Zero is a cloudless scene.

Use the Cloud opacity and Cloud speed parameters to control clouds in the scene.

Dependencies

To enable this parameter, select Override scene weather.

Enable volumetric clouds — Option to enable volumetric clouds

off (default) | on

Select this check box to enable volumetric clouds.

Dependencies

To enable this parameter, select Override scene weather.

Cloud coverage — Unreal Editor Cloud Density global target value

1.0 (default) | any value between 0 and 100

Parameter that corresponds to the Unreal Editor Cloud Density global actor target value, in percent.

Use the Cloud coverage parameter to control clouds in the scene.

Dependencies

To enable this parameter, select Override scene weather and Enable volumetric clouds.

Cloud layer altitude — Unreal Editor Layer Bottom Altitude global actor target value

6 (default) | any value between 5 and 20

Parameter that corresponds to the Unreal Editor Layer Bottom Altitude global actor target value, in km.

Dependencies

To enable this parameter, select Override scene weather and Enable volumetric clouds.

Fog

Fog density — Unreal Editor Set Fog Density and Set Start Distance target values

0 (default) | any value between 0 and 100

Parameter that corresponds to the Unreal Editor Set Fog Density and Set Start Distance target values, in percent.

Dependencies

To enable this parameter, select Override scene weather.

Rain

Rain density — Unreal Editor local actor controlling rain density, wetness, rain puddles, and ripples

0 (default) | any value between 0 and 100

Parameter corresponding to the Unreal Editor local actor that controls rain density, wetness, rain puddles, and ripples, in percent.

Use the Cloud opacity and Rain density parameters to control rain in the scene.

Dependencies

To enable this parameter, select Override scene weather.

Enable raindrops on camera lens — Option to enable raindrops on camera lens

off (default) | on

Select this check box to enable raindrops on the camera lens.

Dependencies

To enable this parameter, select Override scene weather.

Snow

Snow density — Unreal Editor global actor controlling snow density

0 (default) | any value between 0 and 100

This parameter corresponds to the Unreal Editor global actor that controls snow density, in percent.

Dependencies

To enable this parameter, select Override scene weather.

Geospatial

Enable geospatial configuration — Option to enable geospatial parameters and variant subsystem

off (default) | on

Select this check box to enable geospatial parameters and a variant subsystem.

Access token ID — ID of stored token

string representing ID of stored token

ID of stored token, specified as a string. To create this token, create a Cesium Ion^® account, then generate the token through this account. The Authentication Manager stores the token from Cesium Ion. For more information, see Visualize with Cesium (Aerospace Blockset) and https://ion.cesium.com/.

Dependencies

To enable this parameter, select the Enable geospatial configuration check box.

Use Earth center as origin (ECEF) — Use Earth center as origin (ECEF)

off (default) | on

Select this check box to position aerospace vehicles with respect to the Earth center. Use this option with the ECEF coordinate frame selection in the pack blocks.

Origin height (m) — Height at georeference point on globe

real scalar

Height at georeference point on the globe, specified as a real scalar. This parameter represents the height above the 1984 World Geodetic System (WGS84) ellipsoid model of the Earth at the latitude and longitude specified in Origin latitude and Origin longitude.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Clear the Use Earth center as origin (ECEF) check box.

Origin latitude — Latitude

real scalar

Latitude, specified as a real scalar in decimal degrees.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Clear the Use Earth center as origin (ECEF) check box.

Origin longitude — Longitude

real scalar

Longitude, specified as a real scalar in decimal degrees.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Clear the Use Earth center as origin (ECEF) check box.

Map style — Raster overlay type

Aerial (default) | Aerial with labels | Road

Raster overlay type, specified as Aerial, Aerial with labels, or Road.

Dependencies

To enable this parameter, select the Enable geospatial configuration check box.

Additional asset IDs — Local dataset IDs

[] (default) | array | vector

Local dataset IDs, specified as an array or vector.

Dependencies

To enable this parameter, select the Enable geospatial configuration check box.

Use advanced Sun sky — Georeferenced, location-accurate Sun Sky actor

off (default) | on

Select this check box to add a georeferenced, location-accurate Sun Sky actor in simulation.

Dependencies

To enable this parameter, select the Enable geospatial configuration check box.

Solar time — Current solar time

11 (default) | scalar real

Current solar time, specified as scalar hours from midnight.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Select the Use advanced Sun sky check box.

Time zone — Time zone

11 (default) | scalar real

Time zone, specified as hours offset from Greenwich Mean Time (GMT). To specify hours before GMT, use a minus sign (-).

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Select the Use advanced Sun sky check box.

Day — Day

21 (default) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31

Day, specified as a scalar from 1 to 31.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Select the Use advanced Sun sky check box.

Month — Month

9 (default) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12

Month, specified as a scalar from 1 to 12.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Select the Use advanced Sun sky check box.

Year — Year

2022 (default) | scalar real

Year, specified as a scalar real.

Use daylight saving time (DST) — Daylight saving time

off (default) | on

Select this check box to enable daylight saving time.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Select the Use advanced Sun sky check box.

DST start day — Start day of daylight saving time

10 (default) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31

Start day of daylight saving time, specified as a scalar from 1 to 31.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Select the Use advanced Sun sky check box.

DST start month — Start month of daylight saving time

3 (default) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12

Start month of daylight saving time, specified as a scalar from 1 to 12.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Select the Use advanced Sun sky check box.

DST end day — Last day of daylight saving time

3 (default) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31

Last day of daylight saving time, specified as a scalar from 1 to 31.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Select the Use advanced Sun sky check box.

DST end month — Last month of daylight saving time

11 (default) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12

Last month of daylight saving time, specified as a scalar from 1 to 12.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Select the Use advanced Sun sky check box.

DST switch hour — Hour when daylight saving time switches

2 (default) | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24

Hour when daylight saving time switches, specified as a scalar from 1 to 24.

Dependencies

To enable this parameter:

• Select the Enable geospatial configuration check box.

• Select the Use advanced Sun sky check box.

Authentication manager — Management of access tokens

button

Click to manage access tokens, such as create, update, and delete tokens.

Dependencies

To enable this parameter, select the Enable geospatial configuration check box.

More About

Sun Position and Weather

To control the scene weather and sun position, on the Weather tab, select Override scene weather. Use the enabled parameters to change the sun position, clouds, fog, and rain during the simulation.

Sun Position

Use Sun altitude and Sun azimuth to control the sun position.

• Sun altitude — Altitude angle in a vertical plane between the sun rays and the horizontal projection of the rays.

• Sun azimuth — Azimuth angle in the horizontal plane measured from the south to the horizontal projection of the sun rays.

Alternatively, select Enable geospatial sun to use Latitude, Longitude, Date, Time, and Time zone to control sun position. Enabling geospatial sun is useful to simulate conditions near the poles or at locations with disproportionate lengths of day versus night.

This table summarizes sun position settings for specific times of day.

Time of Day	Settings	Unreal Editor Environment
Midnight	Sun altitude: -90 Sun azimuth: 180
Sunrise in the north	Sun altitude: 0 Sun azimuth: 180
Noon	Sun altitude: 90 Sun azimuth: 180

Clouds

Use Cloud opacity and Cloud speed to control clouds in the scene.

• Cloud opacity — Unreal Editor Cloud Opacity global actor target value. Zero is a cloudless scene.

• Cloud speed — Unreal Editor Cloud Speed global actor target value. The clouds move from west to east for positive values and east to west for negative values.

Select Enable volumetric clouds to use Cloud coverage and Cloud layer altitude to control volumetric clouds in the scene.

• Cloud coverage — Unreal Editor Cloud Density global actor target value.

  

• Cloud layer altitude — Unreal Editor Layer Bottom Altitude global actor target value.

  

This table summarizes settings for specific cloud conditions.

Cloud Condition	Settings	Unreal Editor Environment
Clear	Cloud opacity: 0
Heavy	Cloud opacity: 85
Heavy	Enable Volumetric clouds: Selected Cloud Coverage: 50 Cloud layer altitude: 6

Fog

Use Fog density to control fog in the scene. Fog density corresponds to the Unreal Editor Set Fog Density.

This table summarizes settings for specific fog conditions.

Fog Condition	Settings	Unreal Editor Environment
None	Fog density: 0
Heavy	Fog density: 100

Rain

Use Cloud opacity and Rain density to control rain in the scene.

• Cloud opacity — Unreal Editor Cloud Opacity global actor target value.

• Rain density — Unreal Editor local actor that controls rain density, wetness, rain puddles, and ripples.

This table summarizes settings for specific rain conditions.

Rain Condition	Settings	Unreal Editor Environment
Light	Cloud opacity: 10 Rain density: 25
Heavy	Cloud opacity: 10 Rain density: 80

Snow

Use Snow density to control snow in the scene.

• Snow density — Unreal Editor global actor that controls snow density.

This table summarizes settings for specific snow conditions.

Snow Condition	Settings	Unreal Editor Environment
Heavy	Snow density: 50

Version History

Introduced in R2020b

R2024a: Requires Simulink 3D Animation

Simulating models with the Simulation 3D Scene Configuration block requires Simulink 3D Animation.

R2024a: New parameters available to simulate additional weather conditions

Use new weather parameters to simulate additional weather conditions.

Weather	Parameters
Sun	Enable geospatial sun Latitude Longitude Date Time Daylight saving time
Cloud	Enable volumetric clouds Cloud coverage Cloud layer altitude
Rain	Enable raindrops on camera lens
Snow	Snow density

R2023b: Import RoadRunner Scene into Unreal Engine Simulation Environment

Use the Simulation 3D Scene Configuration block to import a RoadRunner scene and simulate in the scene. To specify the source of scene, select the Scene source parameter as RoadRunner. Then, in the Project parameter, specify the Filmbox (.fbx) file corresponding to the RoadRunner scene. For an example, see Import RoadRunner Scene into Unreal Engine Using Simulink (Simulink 3D Animation).

R2023b: Camera View Improvements to View the Virtual World

Use the Simulation 3D Scene Configuration block to view the virtual world from a camera positioned at a custom viewpoint. To set the custom viewpoint, select Scene view as Custom and set the Initial viewer translation and Initial viewer rotation values. You can also use keyboard shortcuts and mouse controls to navigate in the virtual world scene.

R2023a: Cesium support for specifying geospatial coordinates

You can select the Enable geospatial configuration parameter to enable the parameters of the Geospatial tab, such as Access token ID and Georeference parameters. You can use the parameters on the Geospatial tab to specify geospatial origin coordinates using a Cesium access token ID.