Render Buffers
The following are the supported buffer savers in Janus:

• LightWave Render Buffer Export (NewTek - bundled)
• DSTORM Buffer_Saver 1.12 (DSTORM) (3rd-party freeware)
• DPONT GetExtraBuffer Saver (Denis Pontonnier) (3rd-party freeware) (LW9.x only)
• LightWave RPF Export (NewTek - bundled)
• db&w exrTrader (db&w - 3rd-party commercial)

Janus recreates the interface for each of these buffer savers and configures them internally for use. Users are not advised to manually add buffer savers if using in conjunction with Janus. Firstly, it automatically creates directories for the buffers. Secondly, unless it takes control over the creation of the ImageFilter buffer savers, it considers all Image Filter plugins as it would normally. That means the user must always be aware of the effect their commands are making on the activation / deactivation of ImageFilter plugins.

Note that users can use different render buffer savers at the same time, but extra care must be taken to ensure proper image output file paths.

LightWave Render Buffer Export (Newtek) (LWBUFFER)
The “native” or bundled Image Filter plugin of LightWave is the Render Buffer Export. Janus supports this plugin because all LightWave users will certainly have this. Its current implementation only sports one buffer to be exported per plugin instance. Janus, however, consolidates the multiple buffer export functionality into one interface. If multiple buffers are checked for export, it will automatically create as many plugin instances of Render Buffer Export as needed to output those buffers.

Added Subcommand Functionality. LWBUFFER can now be controlled by the subcommand called BUFFERDATA. Here are the parameters available.

When using BUFFERDATA, you must start with the buffer saver's name, followed by the parameter, and then the sub-parameter (if applicable), then the value. Here are some examples:

BufferData"LWBUFFER.diffshd.active.1" (activates Diffuse Shading)

BufferData"LWBUFFER.format.1" (switches format to DeluxeRLA)

Remember that Janus will use default values of the buffer saver. If you do not specify a value for a particular parameter / sub-parameter, then it will just draw on default values. Particularly with the save image format parameter, Janus will use the Global Preferences Save Image Format value automatically, unless you specify a different value.

Here is a summary of the sub-parameters:

• active - turns buffer or parameter on or off. Specify 0 if off, or 1 if on.
• neg - switches the negative parameter for that buffer.
• norm- enables or disables the normalise parameter for that buffer.
• subdir - specifies a subdirectory name.

DSTORM Buffer_Saver 1.12 (D-STORM) (DSTORMBUFFER)
D-Storm's Buffer_Saver is supported because it is freeware, and sports a few extended capabilities from the LightWave Render Buffer Export. Janus's implementation of the Buffer_Saver removes direct access to the Near Clip and Far Clip envelopes that is otherwise available in the plugin. This has been replaced by filename fields pointing to envelope files for each respective field. If you choose to use the envelopes for Near Clip or Far Clip, do so normally in Layout. Then save the envelopes as files (from the Graph Editor) and input the filenames into the Janus's Buffer_Saver interface.

D-Storm's Buffer_Saver's output image structuring differs significantly from the LightWave Render Buffer Export. In Render Buffer Export each pass can have its own subdirectory. However, in D-Storm's Buffer_Saver, only a suffix is attached, and a 'global' base filename is provided for. This base filename has been changed in Janus's implementation to a user-specified subdirectory in which to output the resulting images to.

Denis Pontonnier GetExtraBuffer Saver (Denis Pontonnier) (DPONTBUFFER)
Pontonnier's plugin node for LW9.x is supported because it introduces something useful, novel and beyond the capabilities of either of the two savers listed above. Furthermore, it is freeware and is readily accessible. Janus supports the saving aspect of the GetExtraBuffer node, but does not set up, or in any way assists in the set-up of these nodes. It is necessary to set up the GetExtraBuffer nodes in order for Janus to use it. Janus will only enable you to turn buffers on and off and automate image paths, as well select image format types for each buffer. In the original node, image format can be changed for every buffer. Janus consolidates the image format for all buffers to one.

When using Pontonnier's GetExtraBuffer Saver, be cognizant of the fact that GetExtraBuffer is a node available in both the PixelFilter NE (Node Editor) and ImageFilter NE. As such they are categorised separately. Furthermore, Janus only supports one instance of the GetExtraBuffer Saver node for one instance in PixelFilter NE, and one instance in ImageFilter NE. In other words, do not utilise more than one GetExtraBuffer node for image saving in PixelFilter NE or ImageFilter NE. You may, of course, utilise it for other things if you wish.

Furthermore, in order to correctly identify which GetExtraBuffer node is to be modified by Janus, the user must rename the node has PE_DPONTBUFFER (case-sensitive). This signifies that this node is intended for buffer export. Janus will ignore any other node.

Workflow tip: maintain a consistent "buffer slot assignment", which means to conventionalise which slots are for, say, occlusion, depth, or normals. In this way you do not need to repeatedly assign subdir/suffix names. For example:

• Buffer 1 RGB -> Normals Pass
• Buffer 2 GREY -> Depth Pass
• Buffer 3 RGB -> Background Pass
• Buffer 4 GREY -> Occlusion Pass

And this, ideally, should be standard across all scenes.

** Denis Pontonnier's plugin does not specify its version number. Mr. Pontonnier may issue updates and the reliability of Janus's implementation may be compromised. Therefore no guarantee regarding this aspect of compatibility is given. At the time of this writing GetExtraBuffer was updated on 07/28/2007 and it is only that version that Janus has been tested to work on.

LightWave RPF Export (Newtek) (LWRPFBUFFER)
The bundled RPF Export is supported due to its some of its unique buffers and that it works very well with After Effects and combustion. RPF export has some convenience features like being able to output a normals pass without needing to assign a shader to the objects. All options in the RPF export saver are mimicked in Janus's implementation. RPF export outputs a single RPF file per frame. The Subdir/Suffix input field should correspond to the subdirectory that will be created under that pass and the suffix that will be appended to it. Furthermore you must specify a name in Subdir/Suffix field, or else, Janus's will override this with "RPF". This is needed to avoid clashing with Janus's standard outputs.

db&w exrTrader (DBWEXRBUFFER)
db&w's exrTrader is supported due to its extensive support for the OpenEXR format. Note that you must be a licensed user of db&w's exrTrader to use the Janus front-end for exrTrader. Also note that only exrTrader v1.2 (and up) is supported.

Janus's front-end interface is similar to exrTrader's (for the sake of existing exrTrader users). However, to maintain consistency with the rest of Janus's behaviors, some aspects have been modified:

Image name formatting. Janus's exrTrader front-end gets this settings from its Global Preferences' Frame Digit Padding setting.

'Save LW Output'. This checkbox allows you to enable to disable LightWave's internal saving mechanism. This is a useful control if you intend to work with .exr files exclusively. If unchecked, Janus will disable LightWave's internal saver.

exrTrader Test Render. exrTrader is also specially tied to Janus through the test render. If Use exrTrader for test render is checked Janus will bring up the rendered image saved by exrTrader, rather than LightWave's saver.

Output File. This setting's behavior was not changed; it works just like exrTrader's, therefore be careful when using this in conjunction with multi-layer rendering. Remember that Janus will typically breakout scenes on a per-layer basis. If Output File remains constant throughout those breakout scenes, then they will overwrite each other's renders. Typically you will want to enable Use Render Path for use with Janus. Nevertheless, this setting was still made available just in case a situation needed it.

Envelopes. Envelopes are supported through the pre-saved envelope files. They should point to a valid envelope file.

Subcommand parameters. New to Janus v1.1, and specifically tied to exrTrader is a new subcommand called BUFFERDATA, which allows you to dynamically change an exrTrader preset on a per-pass basis. Once you create your presets in exrTrader, you can tell Janus to use these presets through subcommands.

BUFFERDATA"dbwExrBuffer.preset.savedPresetName1.user"

Planned Support for Other Buffer Savers

Photoshop Export (NewTek)
The LW PSD Export is to be supported for purposes of overall flexibility regarding buffer outputs.