RIB archive, why?

This tutorial will show the benefits of using RIB archives rather than Softimage Stand-ins or any other archiving/referencing method.

There are many ways in which RIB files are used in 3Delight for Softimage.

1. You can completely convert your scene into a renderable RIB file and then use 3Delight Studio Pro to render it using the standalone renderdl command. This is mainly useful for render-farming.
2. Softimage stand-ins are implemented, behind the scenes, using RIB archives. 
3. You can export the scene (or parts of) explicitly to RIB archives. These parts are then replaced by simpler stand-in geometry and loaded using the RIB archive feature. This tutorial covers this perticular point.

The main differences between Softimage stand-ins and RIB archives are summerized in the table below.

Since the RIB archive is a geometry property it needs a host that will support it. Most of the time it should be a simplified representation of the real object. In this tutorial we will first show you how to create a host that will cover the bounding box of the original object. To be more pipeline oriented, we will use a simple Python script in order to generate the bounding box of a selected object:

1. Open Softimage’s script editor and add the following Python code (make sure the scripting language is set to Python):
   

   Softimage - Python

   import os
   # First verify if you have an object selected
   if( len( Application.Selection ) > 0 ):
       object = Application.Selection( 0 )
       # Get the bounding box of the object
       bounding_box = Application.GetBBox(  )
       bb_x_min = bounding_box( 0 )
       bb_y_min = bounding_box( 1 )
       bb_z_min = bounding_box( 2 )
       bb_x_max = bounding_box( 3 )
       bb_y_max = bounding_box( 4 )
       bb_z_max = bounding_box( 5 )
       # Create the host of RIB property. We are using a mesh in order to use any SI property on it.
       cube_bounding_box = Application.ActiveSceneRoot.AddGeometry( 'Cube', 'MeshSurface' )
       cube_bounding_box.Name = object.Name + '_BBox'
       cube_bbox_final_name = object.Name
       cube_bounding_box.length = 1
       # The host of the RIB property should cover the bounding box of the original object.
       cube_bounding_box.PosX = ( bb_x_max + bb_x_min ) / 2
       cube_bounding_box.PosY = ( bb_y_max + bb_y_min ) / 2
       cube_bounding_box.PosZ = ( bb_z_max + bb_z_min ) / 2
       cube_bounding_box.sclx = bb_x_max - bb_x_min
       cube_bounding_box.scly = bb_y_max - bb_y_min
       cube_bounding_box.sclz = bb_z_max - bb_z_min
       Application.FreezeObj( cube_bounding_box )

2. Select an object
3. Execute the script

This will generate the bounding box of the selected object. Now that this is done, we need to create the RIB archive and assign it to the bounding box using the RIB archive.
To perform this action add the following code line to the previous file:

    delight_pref = Application.Dictionary.GetObject( 'preferences.3Delight', False )
    if( delight_pref != None ):
        delight_pref.ExportMaterialsAndAttributes = False
        delight_pref.ExportTransformations = False
    # Promp a folder browser to select the location of your RIB File
    rib_location = XSIUIToolkit.PickFolder( XSIUtils.ResolvePath( '[Project Path]' ), 'RIB Package Location' )
    if( len( rib_location ) != 0 ):
        rib_file = XSIUtils.ResolvePath( rib_location + os.sep + object.Name + '_RIB.[Frame #4].rib' )
        # This will generate the object RIB for this Frame only
        Application.ExportObjectRenderArchive( object, rib_file, int( XSIUtils.ResolvePath( '[Frame #4]' ) ), int( XSIUtils.ResolvePath( '[Frame #4]' ) ), 1, False, False )
        # This will add the RIB Property to the object bounding box
        rib_property = cube_bounding_box.AddProperty( '3Delight RIB Properties', False, object.Name + '_RIB_PROPERTY_3DELIGHT' )
        # This will make sure we are using the delayed mode
        rib_property.Parameters( 'ArchiveType' ).Value = 'Delayed'
        # This will make sure we are rendering the RIB and not the bounding box object
        rib_property.Parameters( 'EnableArchive' ).Value = True
        # This will add the RIB file path to the RIB property
        rib_property.Parameters( 'ArchiveName' ).Value = rib_file
        for property in object.Properties:
            if( property.Type == 'material' ):
                Application.CopyPaste( property, '', cube_bounding_box, 3 )
    
    Application.ResetTransform( cube_bounding_box, 'siCtr', 'siScl', 'siXYZ' )
    Application.DeleteObj( object )

At this point, you have just exported your first object as a RIB file and use it for rendering. You will see that when rendering the result will display the “real” object with the exact same look. Also with this solution, you will still be able to apply transforms to the RIB object and also you will be able to edit the shader, override it or even use camera projection on it. This can be a major advantage when you are working on very complex scenes.

Resulting effects:

• Original scene before the RIB archive:

# ------------------------------------------------------
#   task                     user  kernel    real
# ------------------------------------------------------
# Other                     0.00    0.03    0.35
# Shader Translation        0.03    0.02    0.14
# Scene Parsing            18.52    0.76   19.29
# Main Render               1.15    0.58    1.98
# ------------------------------------------------------
# total                    19.70    1.39   21.75

• Scene after the RIB archive:

# ------------------------------------------------------
#   task                     user  kernel    real
# ------------------------------------------------------
# Other                     0.02    0.00    0.44
# Shader Translation        0.02    0.02    0.14
# Scene Parsing             0.06    0.02    0.07
# Main Render               1.15    0.58    1.98
# ------------------------------------------------------
# total                     1.25    0.6     2.63