Eddy has a large number of built-in AOVs, for both different light paths and utility outputs.
In addition to the built-in AOVs, custom AOVs can be created using Light path expressions and can have custom
output modes and clamping settings.
Note
All standard AOVs support a light tag filter, which will restrict the AOV to include only radiance from the
tagged lights. Creating a custom AOV is only required if specialized light paths are required, more complicated conditions
are required to select the lights, or to change the output modes.
These AOVs select light based on the path taken by the light from the light source to the camera.
beauty
The ‘beauty’ AOV is the default output in Eddy.
It is actually identical to the ‘beauty_without_caustics’ AOV,
as caustics are excluded by default because they can have a high level of noise in a non-bidirectional renderer
like Eddy.
beauty_with_caustics
Includes all light paths, including caustics which are usually excluded from the regular ‘beauty’ AOV.
Direct lighting from light sources only, i.e. a single bounce.
Equivalent light path expression: C[RTV]L
indirect
Indirect lighting only, i.e. secondary light bounces.
Equivalent light path expression: C[RTV][RTVOB].*
emission
Emissive sources only.
Equivalent light path expression: C[LO]
background
Background, i.e. color from rays that don’t hit any object. Not currently used by Eddy.
Equivalent light path expression: CB
reflection
Light from surface reflections. Note this includes diffuse, glossy, and specular reflections. Use the ‘specular’ AOV if
only specular reflections are wanted.
Equivalent light path expression: C<R.>.*
transmission
Light from surface transmission. This include specular refraction as well as sub-surface scattering.
Equivalent light path expression: C<T.>.*
diffuse
Light from diffuse reflection from surfaces.
Equivalent light path expression: C<RD>.*
specular
Light from specular reflection from surfaces.
Equivalent light path expression: C<RS>.*
glossy
Light from glossy reflection from surfaces.
Equivalent light path expression: C<RG>.*
refraction
Light from surface refraction.
Equivalent light path expression: C<TS>.*
subsurface
Light from subsurface transmission.
Equivalent light path expression: C<T[DG]>.*
volume
Light from volumes.
Equivalent light path expression: CV.*
caustics
Light from caustics, i.e. light that has one or more specular bounces before hitting a diffuse surface.
Equivalent light path expression: CD[SG]+[LO]
caustics_all
Light from caustics and caustic secondary bounces. These are the caustics that are removed from the ‘beauty_without_caustics’ AOV.
The secondary caustics would not usually be classified as traditional caustics, but are still a source of noise.
These AOVs are various combinations of the standard light path AOVs.
direct_reflection
Direct lighting from surface reflections. Note this includes diffuse, glossy, and specular reflections. Use the ‘direct_specular’ AOV if
only specular reflections are wanted.
Equivalent light path expression: C<R.>L
direct_transmission
Direct lighting from surface transmission. This include specular refraction as well as sub-surface scattering.
Equivalent light path expression: C<T.>L
direct_diffuse
Direct lighting from diffuse reflection from surfaces.
Equivalent light path expression: C<RD>L
direct_specular
Direct lighting from specular reflection from surfaces.
Equivalent light path expression: C<RS>L
direct_glossy
Direct lighting from glossy reflection from surfaces.
Equivalent light path expression: C<RG>L
direct_refraction
Direct lighting from surface refraction.
Equivalent light path expression: C<TS>L
direct_subsurface
Direct lighting from sub-surface transmission.
Equivalent light path expression: C<T[DG]>L
direct_volume
Direct lighting from volumes.
Equivalent light path expression: CVL
indirect_reflection
Indirect lighting from surface reflections. Note this includes diffuse, glossy, and specular reflections. Use the ‘direct_specular’ AOV if
only specular reflections are wanted.
Equivalent light path expression: C<R.>[RTVOB].*
indirect_transmission
Indirect lighting from surface transmission. This include specular refraction as well as sub-surface scattering.
Equivalent light path expression: C<T.>[RTVOB].*
indirect_diffuse
Indirect lighting from diffuse reflection from surfaces.
Equivalent light path expression: C<RD>[RTVOB].*
indirect_specular
Indirect lighting from specular reflection from surfaces.
Equivalent light path expression: C<RS>[RTVOB].*
indirect_glossy
Indirect lighting from glossy reflection from surfaces.
These AOVs include only objects with the tag ‘collector’ and are used to collect shadows and reflections. See Shadow and reflection collecting for more details.
collector_shadows
Shadows on the collector objects. The shadow value is scaled from 0 to 1, where 0 is no shadow and 1 is full shadow.
Shadows on the collector objects. The shadow value is the difference in color between the shadowed and unshadowed values, i.e. the color that
the shadow has subtracted.
Shadows on the collector objects from direct lighting only. The shadow value is the difference in color between the shadowed and unshadowed values, i.e. the color that
the shadow has subtracted.
The collector objects themselves. This AOV can be useful for debugging collectors, as usually they will also be holdouts and won’t appear in the
normal ‘beauty’ AOV.
The source render used for all the velocity and motion AOV example images.¶
position
The world space position (colors in the example image have been re-scaled).
position_camera
The camera space position.
velocity
The world space velocity (colors in the example image have been re-scaled). By default the velocity of the closest hit point is returned, alternatively the AOV output mode can be changed
to ‘alpha weighted’ to blend the velocity from volumes.
velocity_camera
The world space velocity. By default the velocity of the closest hit point is returned, alternatively the AOV output mode can be changed
to ‘alpha weighted’ to blend the velocity from volumes.
normal
The shading normal of the hit surface (colors in the example image have been re-scaled).
geometric_normal
The geometric normal of the hit surface (colors in the example image have been re-scaled).
depth
The depth of the hit point (colors in the example image have been re-scaled).
uv
The UV coordinates of the surface hit point.
motion
The screen space motion vector of the hit point. By default the motion of volumes are blended using the ‘alpha weighted’ mode, however the
AOV output mode can be changed to ‘closest’ if only the motion of the closest point is desired.
The render settings control whether this AOV will store the forward, backward, or instantaneous motion vectors. The AOVs ‘motion_forward’
and ‘motion_backward’ can be used to explicitly request a particular type (or to output multiple motion vector types from a single render).
If a maximum motion value is specified in the render settings, then these values will be re-scaled from 0 to 1, where 0.5 corresponds to no
motion.
motion_forward
The screen space forward motion vector of the hit point, i.e the vector from the current point to its position in the next frame. By default
the motion of volumes are blended using the ‘alpha weighted’ mode, however the AOV output mode can be changed to ‘closest’ if only the motion
of the closest point is desired.
If a maximum motion value is specified in the render settings, then these values will be re-scaled from 0 to 1, where 0.5 corresponds to no
motion.
motion_backward
The screen space backward motion vector of the hit point, i.e the vector from the current point to its position in the previous frame. By default
the motion of volumes are blended using the ‘alpha weighted’ mode, however the AOV output mode can be changed to ‘closest’ if only the motion
of the closest point is desired.
If a maximum motion value is specified in the render settings, then these values will be re-scaled from 0 to 1, where 0.5 corresponds to no
motion.
id
The ID of the hit object.
opacity
The opacity of the pixel, i.e the colored version of the pixel alpha. Volumes with colored extinction will also have colored opacity.
sample_count
The number of camera samples taken for each pixel (colors in the example image have been re-scaled). When adaptive sampling is used some pixels will need less samples to reach the required error
threshold.
ray_count
The number of rays traced for each pixel (colors in the example image have been re-scaled).