Arnold for Maya

You are able to create two types of Arnold Scene Source product

• Arnold Scene Source
• Arnold Scene Source Proxy

Arnold Scene Source (.ass)

Arnold Scene Source contains whatever user selects when creating the publish instance. Arnold Scene Source can be published as a single file or a sequence of files and its determined by the frame range set on the publish instance. Use those values for producing still or animated standin.

Arnold Scene Source Proxy

The main difference of this product type being possibility to use proxy geometries for viewport performance reasons. If this is not an issue use the first standin type instead. Once the publish instance have been created, there is a proxy_SET created inside of the Main_SET. Meshes assigned to the proxy_SET will be the viewport representation of the standin. Once render triggered, they are switched for the content of the Main_SET on the fly. In order to utilize operators and proxies on the standin, the content and proxy nodes need to share the same names (including the shape names and cbIDs).

note

You can duplicate content keeping all its attributes using maya Group for objects used in Main_SET and proxy_SET each being in distinct Group as maya does not allow having the same objects within the same hierarchy.

Here you can see we are having Content_GRP for renderable objects and Proxy_GRP for viewable objects in the maya viewport. Each having the same objects inside as duplicates differing only by level of detail. Note that offset of Proxy objects is just for sake of clarity and normally would be in the exact same location as high detail meshes for rendering aka Content_GRP.

note

Use Arnold Scene Source product instead as there are not so many requirements / constraints when creating it if viewport performance not an issue.

Validation of the Arnold Scene Source publishes

After triggering publishing via Publisher a round of different validation checks being triggered informing user if anything setup wrong and offering set of Repair actions to fix those issues.

Most common Validator is for checking proper asset hierarchy. Just by following the report you are able to adjust your scene hierarchy to match the desired one.

Here is an example of wrong hierarchy set as the model Groups assigned to the standin being children of the World and no such a hierarchy being allowed so need to be adjusted properly.

And the invalid hierarchy seen in the Maya Outliner

Instead of having the Content_GRP and Proxy_GRP in the standin sets, you should put in the actual objects geometries instead to fix this validation failure. As seen below the correct one:

Validators ASS has relative texture paths and Validate Arnold Scene Source cbID allows you to set up the context correctly by using Repair action.

Once all Validators being resolved you are ready to publish the Arnold Scene Source aka Standin product with the .ass representation being ready to be loaded using Loader tool located in the Ayon toolset.

Using Standins

You can use published standin in your workfile via AYON / Load action. User is able to load Arnold Scene Source , Arnold Scene Source Proxy and even Alembic products as standin allowing taking advantage of arnold features also for other products like animation and pointcache.

Arnold Standins

You can highly optimize your workfiles by introducing standins instead of regular reference loading of products like animation as there wont be any files referenced-in just local standin but still managable using Scene Inventory.

Standins and LookDev

Standin supports look products and its assignment. If look product being available, You can assign the look to the loaded Arnold Scene Source ass and Alembic abc using

AYON -> Look Assigner...

Current Standins Limitation

Look assignment is not possible when using Arnold Scene Source Proxy

Limited support for shader assignments with standin nodes

Limited amount of attributes supported by using operator to assign shaders to the loaded standins.

primaryVisibility
castsShadows
receiveShadows
aiSelfShadows
aiOpaque
aiMatte
aiVisibleInDiffuseTransmission
aiVisibleInSpecularTransmission
aiVisibleInVolume
aiVisibleInDiffuseReflection
aiVisibleInSpecularReflection
aiSubdivUvSmoothing
aiDispHeight
aiDispPadding
aiDispZeroValue
aiStepSize
aiVolumePadding
aiSubdivType
aiSubdivIterations

Arnold Scene Source Proxy

If a product has a proxy_SET representation, this will be used as display in the viewport. At render time the standin path will be replaced using the recommended string replacement workflow:

https://help.autodesk.com/view/ARNOL/ENU/?guid=arnold_for_maya_operators_am_Updating_procedural_file_paths_with_string_replace_html

for advanced users

You can stop the proxy swapping by disabling the string replacement operator found in the container.