User guide

hierarchy in the UI. Complexity is controlled by only executing filters on locations in the scene graph that the user

has expanded.

A scene does not need to be entirely loaded in order to be lit. In Katana, you create recipes that allow scene data to

be generated, rather than directly authoring the scene data itself. It is only the renderer that needs the ability to see

all of the scene data, and then only when it needs it. Katana provides access to any part of the scene data if you need

to work on it. You can set an override deep in the hierarchy or, examine what attribute values are set when the filters

run, but you can work with just a subset of the whole scene data open at a time. This is key to how Katana deals with

scenes of potentially unlimited complexity.

NOTE: As Katana uses procedurally defined iterators, it's possible to define an infinitely sized scene graph,

such as a scene graph defining a fractal structure. An infinite scene graph can never be fully expanded, but

you can still work with it in Katana, opening it to different depths, and using rule based nodes to set up

edits and overrides.

Katana in Look Development and Lighting

Katana's scene generation and filtering are presented as a primary artist facing tool for look development and

lighting by having filter functions that allow you to perform all of the classic operations carried out in look

development and lighting, such as:

• Creating instances of shaders, or materials, out of networks of components

• Assigning shaders to objects

• Creating lights

• Moving lights

• Changing visibility flags on objects

• Defining different render passes

Katana's node-based interface provides a natural way to create recipes of which filters to use. Higher level operations

that may require a number of atomic level filters working together can be wrapped up in a single node so that the

final user doesn't have to be concerned with every individual fine-grain operation. Multiple nodes can also be

packaged together into single higher level compound nodes (Groups, Macros and Super Tools).

Technical Docs and Examples

Technical documents and reference examples of specific parts of Katana can be found in the Katana installation in

${KATANA_ROOT}/docs/

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