Houdini 13.0 Nodes

interface version 1

Merges specified takes together into a (temporary) new take, then renders the result.

The takeMerge ROP merges all the specified takes together, then calls the specified output driver.

It allows you to work around the hierarchical nature of takes: they will behave more like 'tags' or 'labels' (or 'overrides' in other applications).

Examples of...

...what can be stored in takes

  • render layer settings (object flags) (say character, background)

  • settings for single-frame mplay or output image sequence (say singleframe, sequence)

  • render quality settings (say draft, production)

...how do you combine (merge) them

  • 'draft singleframe' to get a quick render of the scene

  • 'production character singleframe' to get a production-quality single frame render of the character

  • 'draft background sequence' to get a rough-quality image sequence of the background layer

With regular hierarchical takes all of the above is much harder to achieve.

Parameters

HQueue Mode

Enable this if the resulting render will be distributed using HQueue. (see “Usage with HQueue” below for instructions).

Merged Take Name

The name of the new take (the merge result) that will be rendered.

The default settings is to inherit the name of the node, as it is recommended to give each takeMerge node the name of the render layer it represents.

This take is temporary: it exists only during render and gets deleted on completion.

Warning The name of this take must be unique: no take should exist with the same name.

Output Driver

The name of the ROP node that is called after the merged take is activated.

Warning The Output Driver ROP node must be set to render the '(Current)' take. Also, the Output Driver must be specified with an absolute path.

Takes

The list of take names to be merged. Each text field can contain multiple take names (this allows for more flexible editing.)

Non-existing take names are silently ignored.

Test–Create/Update Merged Take (button)

This convenience button allows you to manually check the results of the take merge: it creates the merged take but will not render it.

The other button deletes the temporary take (you have to switch back to the Main take manually first).

Tip

If you want to use a single Output Driver:

  • specify $ACTIVETAKE.$F4.exr (or similar) as output file name in your ROP node

  • for each takeMerge node that represents a render layer, name it after the layer it represents

This way you can run all your layers through a single ROP node, and all resulting image sequences will be named appropriately.

Tip

One reason why there are multiple 'Takes' text fields is to allow editing of single lines when multiple nodes are selected without changing the other fields.

This fact you can work with to your advantage (using specific fields for specific types of overrides ... I mean takes).

Usage with HQueue

This ROP can be used with the HQueue Render node, but frame ranges are to be set up in a certain way so the HQueue Render node can break down the process to smaller chunks.

The following steps are needed:

  • Enable HQueue Mode on the Take Merge ROP.

  • Set up your desired frame range on the Take Merge ROP (range controls are hidden unless in HQueue Mode).

  • Set 'Render Any Frame' on the Output Driver called by the Take Merge ROP. (Warning: Make sure that none of the applied takes set an explicit render range on your Output Driver!)

  • Set the Take Merge ROP as the output driver for the HQueue Render node.

  • Render with the HQueue Render node.

This setup is necessary because the HQueue Render node requires the frame range settings to be available right on the specified Output Driver (the Take Merge ROP in this case).

Make sure the ROP node that does the actual rendering has 'Render Any Frame' set – if it has a frame range set, it will render that range for each frame-render job created by HQueue!

Release Notes

interface version 1 —

2014-09-17

Error messages are now properly propagated to asset container

2013-08-31

Help card update.

older versions —

Version 0.0.3

  • Added on/off toggle for each take list field.

Version 0.0.2

  • Merge code rewritten in Python.

  • Lifted known limitation of ignoring contents in take hierarchy parents.

  • Changed UI to support variable number of Take lines.

  • A Prettier icon. :)

Version 0.0.1

First prototype. Known limitation: hierarchical parent contents for takes not included when merging.