A function required to get pieces of information in the studio.
It is generally used for acquiring state of items and performing operation on items from VCI script.
For information on items in VirtualCast, refer to VirtualCast TOP.

For the latest list of the functions, refer to “types.lua” file in “EmbeddedScriptWorkspace” folder.

Has functions and Get functions exist for each of the preset items in VirtualCast.
Has function is a function to check if the item exist in the studio and Get function is a function to acquire the instance of an item.
Using Get on items that don't exist in the studio will give you null, so only use Get when the result of the Has function is true.
Note that, as of 29th August 2019, items that can also be spawned by guests cannot be acquired.

*1
SetPosition SetRotation SetLocalPosition SetLocalRotation are only executable from VCIs spawned by the room owner themself.

It's basically the same with the SystemItem, but there exists some functions unique to the camera.

*1
SetPosition, SetRotation, SetLocalPosition, SetLocalRotation and “SetFieldOfView” are only executable from VCIs spawned by the room owner themself.

*2
Bellow is the list of the cameras that can have the FOV specified. You cannot specify a value that exceeds the value acquirable with GetMinFieldOfView and GetMaxFieldOfView.

Example

main.lua

function onUse(use)
    -- When PositionReset is used
    if use == "CameraPositionReset" then
        -- Reset the position of the camera
        CameraPositionReset()
    end
end
 
function CameraPositionReset()
    -- End if handy camera doesn't exist
    if vci.studio.HasHandiCamera() == false then
        print("Handy camera doesn't exist. End.")
        return
    end
 
    -- The coordinate to reset
    local position = Vector3.__new(0, 1, 0)
    -- Instance of the camera
    local camera = vci.studio.GetHandiCamera()
    -- Change the position of the camera
    camera.SetPosition(position)
    print("Camera position　："..tostring(camera.GetPosition()))
end

The result

Camera position : (0,1,0)
(The camera moves to (0,1,0) in the world coordinate)

Explanation

In this example, the position of the handy camera is reset to (0,1,0) when a SubItem called CameraPositionReset is reset.

    if vci.studio.HasHandiCamera() == false then
        print("Handy camera doesn't exist. End.")
        return
    end

Executing vci.studio.GetHandiCamera() when the handy camera is non-existent in the studio will cause an error.
So when vci.studio.HasHandiCamera() == false (handy camera doesn't exist), it returns to end the process.

When vci.studio.HasHandiCamera() == true, the return will not be executed and it reaches camera.SetPosition(position), which will reset the camera.
Therefore, you must always use Has function to check the existence of an item before instantiating an item with Get function.

It's a case-by-case, but it is recommended to use when Has function is false, then return idiom.
While there is no big deal with when true, then do this strategy, it tends to result in variables being kept inside the scope of the if statement. It could also result in if statements nested inside the if statement.
**When Has function is false, then don't do this“ is more definitive, so we recommend you to bring this in the front.
This way of writing a program is called the Guard.