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Per-light AOVs

AOV Shaders

AOVs

Light Path Expressions

Per-light AOVs

A set of AOV shaders exists to allow easy reading and writing of AOVs from within a shader network.

AOV Shaders  

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AOV Shaders AOV Shaders

AOVs 

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AOVs AOVs

• To add an AOV click on the + button.

• To choose the type of AOV click on the down arrow to the right of AOV 1. You will see a list of available AOVs (with their associated LPE).

Layer Name

Output layer names can be customized in file formats that support layers (regular or deep EXR) by adding an optional custom layer name after the driver name in the options.outputs string. E.g.

outputs 2 1 STRING
 "RGBA RGBA gaussian_filter driver_exr beauty"
 "RGBA RGBA variance_filter driver_exr beauty_variance"

Light Path Expressions 

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Light Path Expressions Light Path Expressions

You can define custom Light Path Expressions to write lighting components into separate AOVs. 

Separate File

Render the AOV in a separate file, as opposed to storing it in as an additional channel of the beauty image.

Denoise

Image Format

Specifies the image format of the AOV if it is being rendered to a separate file. See the Image Format section for more information. By default, this will be the same as the beauty.

Type

The type of data to be written in the AOV - RGBA, float, vector, etc. At the moment Arnold for Houdini will not specify a default type for each AOV so you will have to explicitly set this. This will be updated in a future release. Refer to the list below for what type to use for each AOV.

• Depth [z] - float
• Point [P] - point
• Nomal [N] - vector
• Object Labels [ID] - rgb
• Opacity - rgb
• CPU Time - float
• Ray Count - float
• Shader Layers - rgb

Precision

Specify whether 16-bit floating point (binary16) or full 32-bit precision is used. By default, this will be the same as the beauty.

Compression

Allows you to set multiple EXR compressions per AOV.

Pixel Filter

Specifies the pixel filter used on the AOV, see the Pixel Filter section for more information. By default, this will be the same as the beauty.

Filter Deep AOV

If set to false disables any filtering operation on this layer's raw data. Useful for normals or ID layers.

Deep AOV Tolerance

Tolerance over which the AOV samples will not be merged together.

Half Precision for Deep AOV

Use 16-bits float for this AOV filtering.

Per-light AOVs 

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Per-light AOVs Per-light AOVs

Each light object has an 'AOV Light Group' attribute which can be used to write out the light contribution to a separate AOV with a corresponding name. To create a per-light AOV you must do the following:

1. Enter a name for the per-light AOV in the 'AOV Light Group' of the light. 

2. Add a custom AOV in the Render Output. For example, if the light group name is “red”, then the AOV name should be RGBA_red (if you want the red light contribution to the beauty). Or diffuse_red if you want just the red light contribution to the diffuse.