v5.0
SetGlobal and its companion command GetGlobal provide a simple means to store and
retrieve values which act like "global variables". Each variable is
indentified by a unique string. To change the value of a previously
set variable call this command with a new value. To erase a global
variable call this command with null as the value.
These variables are accessible from any script and remain active
during the duration of the Softimage session.
Warning: For persistent Global values it is better to use a
CustomProperty or a
Custom Preferences
object.
Tip 1: It is possible to store a Softimage object inside a global
variable. However when storing a reference to a Softimage object,
it is often safer to store the fullname string of the object rather
than the object itself. This ensures that even if the scene is
closed, reopened or significantly changed you can get a valid
reference to the object (as long as the object isn't renamed). This
is demonstrated in the examples below.
Tip 2: This command will convert any JScript Array or user-created
script object into a SAFEARRAY (see Array). To maintain the data in its
original form use SetGlobalObject.
Tip 3: It is unnecessary to use this functionality if the entire
plug-in is implemented inside a single script, because any variable
within the global scope is accessible inside all functions. (The
only exception is PPGLayout
logic callbacks, which cannot read the values of global variables
set by non-PPGLayout callbacks.)
Tip 4: Global variables can be very useful, but usage should be
kept to a minimum to avoid unexpected side-effects, "spagetti" code
and code that is difficult to read, debug and maintain. Each global
variable name should be well chosen to avoid potential conflict
with other scripts. For example if two plug-ins both try to use a
global variable named "x" then both will be prone to random or
unexpected failure.
Tip 5: This feature is implemented as a self-installed JScript
Plugin using the powerful
"Scripting.Dictionary" object which is available to both VBScript
and JScript. For more details refer to the actual implementation
code (GlobalVarPlugin.js).
SetGlobal( in_VariableName, in_Value ); |
Parameter | Type | Description |
---|---|---|
in_VariableName | String | The name of the global variable |
in_Value | Variant | A new value for the global variable |
// Example test for GetGlobal/SetGlobal NewScene( null, false ) ; // null returned when Global hasn't been set ASSERT( null == GetGlobal( "X" ) ) ; SetGlobal( "X", 67 ) ; ASSERT( 67 == GetGlobal( "X" ) ) ; // You can change the value of the global SetGlobal( "X", "foo" ) ; ASSERT( "foo" == GetGlobal( "X" ) ) ; // Remove the global SetGlobal( "X", null ) ; // Handle Softimage Object var oGrid = ActiveSceneRoot.AddGeometry( "Grid", "MeshSurface", "mygrid" ); // You could store a Softimage object as a Global SetGlobal( "InterestingObj", oGrid ) ; ASSERT( oGrid.Name == GetGlobal( "InterestingObj" ).Name ) ; // But it is better to store the string fullname // because oGrid won't survive saving and reloading the scene, SetGlobal( "InterestingObj", oGrid.FullName ) ; // Simulate the user closing and reopening the scene var strTestScene = Application.InstallationPath( siProjectPath ) + "\\Scenes\\Test.Scn" ; SaveSceneAs( strTestScene ) ; OpenScene( strTestScene, false ) ; var strGrid = GetGlobal( "InterestingObj" ) ; // Turn the string back into an object var oGridRevived = Dictionary.GetObject( strGrid ) ; ASSERT( oGridRevived.Name == "mygrid" ) ; // Demonstrate that it really is a valid reference to the grid oGridRevived.posx = 4 ; LogMessage( "Test complete" ) ; function ASSERT(in_val) { if ( !in_val ) throw new Error( 0, "test failed" ); } |
' Example test for GetGlobal/SetGlobal NewScene ,false ' null returned when Global hasn't been set ASSERT( Null = GetGlobal( "X" ) ) SetGlobal "X", 67 ASSERT( 67 = GetGlobal( "X" ) ) ' You can change the value of the global SetGlobal "X", "foo" ASSERT( "foo" = GetGlobal( "X" ) ) ' Remove the global SetGlobal "X", Null ' Handle Softimage Object set oGrid = ActiveSceneRoot.AddGeometry( "Grid", "MeshSurface", "mygrid" ) ' You could store a Softimage object as a Global SetGlobal "InterestingObj", oGrid ASSERT( oGrid.Name = GetGlobal( "InterestingObj" ).Name ) ' But it is better to store the string fullname ' because oGrid won't survive saving and reloading the scene, SetGlobal "InterestingObj", oGrid.FullName ' Simulate the user closing and reopening the scene strTestScene = Application.InstallationPath( siProjectPath ) & "\Scenes\Test.Scn" SaveSceneAs strTestScene OpenScene strTestScene, false strGrid = GetGlobal( "InterestingObj" ) ' Turn the string back into an object set oGridRevived = Dictionary.GetObject( strGrid ) ASSERT( oGridRevived.Name = "mygrid" ) ' Demonstrate that it really is a valid reference to the grid oGridRevived.posx = 4 LogMessage "Test complete" sub ASSERT( in_test ) if NOT in_test then LogMessage "Test Failed", siError end if end sub |