## FCurveEditor

Object Hierarchy

### Introduced

v3.0

### Description

This object provides the context information of the Softimage FCurve editor. By using the information exposed by this object, it is possible to write custom fcurve editing scripts or plug-ins which react to user's actions in the FCurve Editor.
In order to access an instance of this object you need to create a custom command with the siCommandCategory set to siFCurveCategory. This command will appear in the edit menu of the fcurve editor so that the user can execute it on demand. The command takes a single argument, which is a pointer to an instance of the FCurveEditor object.
Using the methods and properties of the FCurve and FCurveKey objects the custom command can change the fcurves. The user interface will update automatically to reflect any changes made to the underlying fcurve objects.
The following example demonstrates two custom fcurve editor scripts, and there are more examples in Netview, under XSI Local: Tools: Animate.

### Methods

GetEditorAttribute2 | GetSelectedKeys2 |  |

### Properties

EditorAttribute | SelectedFCurves | SelectedKeys |

### Examples

#### VBScript Example

    '
    ' Custom FCurve Command Demo
    '
    'This script demontrates the Softimage support for plugging in a
    'custom command.
    '
    'Instructions:
    '
    '1) In order to try this code the commands needs to be saved onto disk in a .vbs
    'file so that it can be registered.
    '
    '2) install the commands using the following, (changing the path according to your config):
    '  xsi -script "C:/temp/FCurveDemo.vbs" -main InstallFCurveCmdExamples -args -Location "c:/temp/FCurveDemo.vbs"
    '
    '3) Launch Softimage,
    '4) Create some animated parameters,
    '5) Open the fcurve editor, select curves and keys from your animated parameters
    '6) Try the FCurveEditorInfo and AvgSelectedPoints commands which will appear in the Edit menu
    sub InstallFCurveCmdExamples( Location )
            dim cmd
            'Location argument is expected to be the full path name of the script file
            'where the commands we are installing are implemented
            logmessage "Installing fcurve editor commands found in " & Location
            'Remove any existing earlier registrations of this command
            Application.RemoveCommand "FCurveEditorInfo"
            Application.RemoveCommand "AvgSelectedPoints"
            set cmd = Application.CreateCommand("FCurveEditorInfo", siFCurveCategory)
            cmd.Description = "FCurveEditorInfo shows information about FCurve Context"
            cmd.ScriptingName = "FCurveEditorInfo"
            cmd.Handler = "OnFCurveEditorInfo"
            cmd.FileName = Location
            cmd.Language = "VBScript"
            'FCurve callbacks are a sub not a function
            cmd.ReturnValue = false
            'FCurve commands get a pointer to an FCurveEditor OM object
            cmd.Arguments.Add "FCurveEditor", siArgumentInput, 0, siDispatch
            Application.AddCommand cmd
            logmessage "FCurveEditorInfo is now added to fcurve editor Edit menu"
            set cmd = Application.CreateCommand("AvgSelectedPoints", siFCurveCategory)
            cmd.Description = "AvgSelectedPoints change value of selected keys"
            cmd.ScriptingName = "AvgSelectedPoints"
            cmd.Handler = "OnAvgSelectedPoints"
            cmd.FileName = Location
            cmd.Language = "VBScript"
            cmd.ReturnValue = false
            cmd.Arguments.Add "FCurveEditor", siArgumentInput, 0, siDispatch
            Application.AddCommand cmd
            logmessage "AvgSelectedPoints is now added to fcurve editor Edit menu"
    end sub
    'This first demo is informative - it logs a bunch of information about the
    'state of the FCurve editor, in effect demonstrating what you can find out
    sub OnFCurveEditorInfo( in_objFCurveEditor )
            LogMessage "FCurveEditorInfo called - showing information about current context of FCurve Editor"
            if ( typename( in_objFCurveEditor ) = "Nothing" ) then
                    Logmessage "FCurve Argument is NULL"
            elseif ( typename( in_objFCurveEditor ) <> "FCurveEditor" ) then
                    LogMessage "FCurve Argument is not an FCurve, it is a " & typename( in_objFCurveEditor )
            else
                    'Now access the FCurve Context listing the contents.
                    dim oCurves, oCurve
                    set oCurves = in_objFCurveEditor.SelectedFCurves
                    if ( oCurves.Count = 0 ) then
                            logmessage "There are no selected fcurves in the editor"
                    end if
                    dim i, strInfo
                    for each oCurve in oCurves
                            logmessage "-------------------------------------"
                            'build a string description of the frame/keyvalues
                            '(for a real motion capture fcurve this would be too long to display like this)
                            strInfo = ""
                            for i = 0 to ( oCurve.Keys.Count - 1 )
                                    strInfo = strInfo & "(" & Round( oCurve.Keys.Item( i ).Time, 3 ) _
                                                            & ", " & Round( oCurve.Keys.Item( i ).Value, 3 ) & ") "
                            next
                            LogMessage "Selected FCurve has the following keys: " & strInfo
                            'List the selected keys
                            dim oKeys, oKey
                            set oKeys = in_objFCurveEditor.SelectedKeys( oCurve )
                            if ( oKeys.Count = 0 ) then
                                    logmessage "There are no keys selected on this fcurve"
                            else
                                    strInfo = ""
                                    for each oKey in oKeys
                                            strInfo = strInfo & "(" & Round( oKey.Time, 3 ) & ", " & Round( oKey.Value, 3 ) & ") "
                                    next
                                    LogMessage "The following keys are selected on this FCurve: " & strInfo
                            end if
                    next
                    'The user may have selected a region in the fcurve editor.  This information is available like this:
                    logmessage "-------------------------------------"
                    dim Start, endFrame, Min, Max
                    Start = in_objFCurveEditor.EditorAttribute( siRegionStartFrame )
                    endFrame = in_objFCurveEditor.EditorAttribute( siRegionEndFrame )
                    Min = in_objFCurveEditor.EditorAttribute( siRegionMin )
                    Max = in_objFCurveEditor.EditorAttribute( siRegionMax )
                    if ( Start <> endFrame ) then
                            logmessage "User has selected time region from frame " &_
                                                    round( Start, 2 ) & " to " & round( endFrame, 2 )
                    else
                            logmessage "No time region is selected"
                    end if
                    if ( Min <> Max ) then
                            logmessage "User has selected key value range from " &_
                                                    round( Min, 2 ) & " to " & round( Max, 2 )
                    else
                            logmessage "No Value region is selected"
                    end if
            end if
    end sub
    'This second demo is action oriented - it changes the state of the FCurves that are selected.
    '
    'In this case we take the selected keys and set their values to the average.
    sub OnAvgSelectedPoints( in_objFCurveEditor )
            LogMessage "AvgSelectedPoints called"
            'Example of some simple error handling
            if ( typename( in_objFCurveEditor ) <> "FCurveEditor" ) then
                    LogMessage "Invalid argument to command - Should be FCurveEditor object instead we got a " _
                                            & typename( in_objFCurveEditor ), siError
                    exit sub
            end if
            dim bDidSomething
            bDidSomething = false
            dim oCurves, oCurve
            set oCurves = in_objFCurveEditor.SelectedFCurves
            for each oCurve in oCurves
                    dim oKeys, oKey, cntKeys
                    set oKeys = in_objFCurveEditor.SelectedKeys( oCurve )
                    cntKeys = oKeys.Count
                    if ( cntKeys > 1 ) then
                            dim sumValues, avgValue
                            sumValues = 0
                            for each oKey in oKeys
                                    sumValues = sumValues + oKey.Value
                            next
                            avgValue = sumValues / cntKeys
                            for each oKey in oKeys
                                    oKey.Value = avgValue
                            next
                            bDidSomething = true
                    end if
            next
            if ( not bDidSomething ) then
                    LogMessage "Please select two or more keys on an fcurve to average"
            end if
    end sub

### See Also

Command FCurve