GetValue
v1.0
Returns the value of a parameter at a specific frame. This is a
very powerful command because it can apply to any parameter, and it
can convert a return value to an object in some cases. It also
isn't necessarily tied to a parameter, as in the case of using it
to return a collection of selected objects.
The example below demonstrates how versatile this command is. It
returns whatever value the parameter contains, no matter what type
of value it is. If the parameter or entity is attached to an
object, then the object is returned, rather than a simple data
value (like a string with the name of the object). For example, the
following statement returns an XSICollection of selected
items:
Set objSel = GetValue( "SelectionList" )
Note: If this command returns an object (instead of a simple data
value) and you are using VBScript, you must use the 'Set' keyword
in order to get the object. If you omit 'Set', the string name of
the object(s) is returned instead.
On the other hand, if you try to assign a simple data value to an
object, this command generates an 'Object required' error message.
For example, if you tried to assign the returned posx value as an
object as in this case:
Set dblX = GetValue( "circle.kine.local.pos.posx" )
You can usually test for the return value by using the TypeName()
function for VBScript (which reports back object type as well as
simple data type). For JScript, you can use the ClassName() method,
which reports on the object type or the typeof operator, which
reports only on the simple data type.
The counterpart to this command is the SetValue command, which allows you to set
parameter values.
The Object Model provides alternatives to GetValue and SetValue.
For example, parameter values can be retrieved and modified using
Parameter.Value as
demonstrated in the second example below. In addition, objects can
be retrieved using Dictionary.GetObject.
oVariant = GetValue( Target, [Time] ); |
| Parameter | Type | Description |
|---|---|---|
| Target | String | Parameter value to retrieve. |
| Time | Number | Frame at which to get the value.
Default Value: Current frame. |
'
' This example just demonstrates some of the different values
' you can find using this command.
' NB: If you want to use the GetValue command to return
' an object, you need to use the 'Set' keyword for VBScript
'
rtn = GetValue("Camera.aspect")
LogMessage TypeName(rtn) ' returns Double
rtn = GetValue("Camera.kine.posz", 25)
LogMessage TypeName(rtn) ' returns Boolean
rtn = GetValue("light.Name")
LogMessage TypeName(rtn) ' returns String
' GetValue() on an object just returns the object:
set rtn = GetValue("Layers.Layer_Default")
LogMessage TypeName(rtn) ' returns Layer
' You can also convert the selection list to the selection object
set rtn = GetValue("SelectionList")
LogMessage TypeName(rtn) ' returns Object (= collection)
LogMessage rtn.Type ' returns XSICollection
LogMessage TypeName(rtn(0)) ' returns X3DObject
|
/* This example demonstrates how you can get and set parameter values using one of the following: (1) GetValue or SetValue scripting commands (2) the Parameter object (long version) (3) a shortcut to the Parameter object */ NewScene( null, false); // First start by getting an object pointer to the sphere, which we will // use with the object model versions ActiveSceneRoot.AddGeometry( "sphere", "meshsurface" ); var oSphere = ActiveSceneRoot.FindChild( "Sphere" ); // (1) Change the sphere's posx value using commands: dblX = GetValue( "sphere.kine.local.pos.posx" ); dblX = dblX - 1.25; SetValue( "sphere.kine.local.pos.posx", dblX ); // (2) Restore the value but this time use the OM (long way) dblX = oSphere.Kinematics.Local.Parameters( "posx" ).Value; dblX = dblX + 1.25; oSphere.Kinematics.Local.Parameters( "posx" ).Value = dblX; // (3) Change the value back again with the OM shortcut dblX = oSphere.posx.Value; dblX = dblX + 1.25; oSphere.posx.Value = dblX; |