Command System

Unreal Engine 4 has some built-in commands to help game development. These commands can be typed into a built-in console. Using these commands, a developer can profile the game performance and view debug information. To invoke the built-in console of a game, type the ` key (the key above tab).

UnrealCV provides commands useful for computer vision researchers. What is more, these commands can be used by an external program. A built-in command can also be used using the special command vrun.

Command cheatsheet

See this ipython notebook to see an imcomplete demo of available commands.

1. Camera operation

See Source/UnrealCV/Private/Commands/CameraHandler.h(.cpp) for more details.

vget /camera/[id]/location
(v0.2) Get camera location [x, y, z]
vget /camera/[id]/rotation
(v0.2) Get camera rotation [pitch, yaw, roll]
vset /camera/[id]/location [x] [y] [z]
(v0.2) Set camera location [x, y, z]
vset /camera/[id]/rotation [pitch] [yaw] [roll]
(v0.2) Set camera rotation [pitch, yaw, roll]
vget /camera/[id]/[viewmode]
(v0.2) Get [viewmode] from the [id] camera, for example: vget /camera/0/depth
vget /camera/[id]/[viewmode] [filename]

(v0.2) Same as the above, with an extra parameter for filename

filename:Filename is where the file will be stored.
example:vget /camera/0/lit lit.png
vget /camera/[id]/[viewmode] [format]

(v0.3.7) Support binary data format

format:If only file format is specified, the binary data will be returned through socket instead of being saved as a file.
example:vget /camera/0/lit png
vget /camera/[id]/object_mask
(v0.2) The object mask is captured by first switching the viewmode to object_mask mode, then take a screenshot
vset /viewmode [viewmode]
(v0.2) Set ViewMode to (lit, normal, depth, object_mask)
vget /viewmode
(v0.2) Get current ViewMode
vget /camera/[id]/pose
(v0.3.10) Get camera location [x, y, z] and rotation [pitch, yaw, roll]
vset /camera/[id]/pose [x] [y] [z] [pitch] [yaw] [roll]
(v0.3.10) Teleport camera to location [x, y, z] and rotation [pitch, yaw, roll]
vget /camera/[uint]/horizontal_fieldofview
(v0.3.10) Get camera horizontal field of view
vset /camera/[uint]/horizontal_fieldofview [FOV]
(v0.3.10) Set camera horizontal field of view
vget /camera/[uint]/vis_depth npy
vget /camera/[uint]/plane_depth npy

2. Object interaction

See Source/UnrealCV/Private/Commands/ObjectHandler.h(.cpp) for more details

vget /objects
(v0.2) Get the name of all objects
vget /object/[obj_name]/color
(v0.2) Get the labeling color of an object (used in object instance mask)
vset /object/[obj_name]/color [r] [g] [b]
(v0.2) Set the labeling color of an object
vset /object/[str]/show
(v0.3.10) Show object
vset /object/[str]/hide
(v0.3.10) Hide object

3. Plugin commands

See Source/UnrealCV/Private/Commands/PluginHandler.h(.cpp) for more details.

vget /unrealcv/status
(v0.2) Get the status of UnrealCV plugin
vget /unrealcv/help
(v0.2) List all available commands and their help message

4. Action commands

See Source/UnrealCV/Private/Commands/ActionHandler.h(.cpp)

vset /action/keyboard [key_name] [delta]
(v0.3.6) Valid key_name can be found in here
vset /action/game/pause
(v0.3.10) Pause the game
vset /action/game/level [level_name]
(v0.3.10) Open a new level
vset /action/input/enable
(v0.3.10) Enable input
vset /action/input/disable
(v0.3.10) Disable input
vset /action/eyes_distance [eye_distance]
(v0.3.10) Set the eye distance between left eye and right eye (camera 1). This command might be marked as deprecated when we finish multiple camera support.

Run UE4 built-in commands

vrun [cmd]
(v0.3) This is a special command used to execute Unreal Engine built-in commands. UE4 provides some built-in commands for development and debug. They are not very well documented, but very useful.

A few examples are:

  • stat FPS - show current frame rate
  • shot - take a screenshot
  • show Material - toggle the display of Material

These commands can be executed in the UE4 console. If you want to use them in UnrealCV, you can prefix these commands with vrun stat FPS.

Run Blueprint commands

vexec [cmd]