Hey folks, we’re considering deprecating ArResolver::IsContextDependentPath to reduce complexity in the system; by default we will treat every path as context dependent and therefore in need of explicit asset resolution.
Removal of this function means that
Queries to the Sdf layer registry will by default attempt to resolve identifiers – layer queries will be based on their resolved path instead of their identifiers. We’ve found no perceptible performance regressions from this change.
Asset localization (used also by usdz construction api) will no longer attempt to preserve relative paths. Instead, localization will resolve every path regardless of whether it is AR context dependent and nest it to a generated subdirectory within the package. Usdz packages from before this change will continue to be compatible with future USD versions and Usdz packages after this change will be backwards-compatible – only the internal structure will be different.
Are there any concerns, comments, or current usage surrounding this API that we should be aware of?
The removal of ArResolver::IsContextDependentPath is not as much of a concern as is the change to the Sdf layer registry.
Our asset identifiers are typically URLs which point to regional servers where latency really affects the time to resolve the asset.
If all calls to the Sdf layer registry require the asset identifier to be resolved, the concern is that we will see a performance regression for URL based asset identifiers. It’s hard to know for sure without benchamarking some of our production assets against it, but it is a concern.
Before this lands on dev will there be any way to test this new behavior so different sites can run benchmarks?
Not a concern, just a quick question about this. Will this also remove the need to add
“implementsContexts”: true,
in pluginfo.json as well? Or will that remain as a way to flag that a Resolver is globally not using context?
Hi Derek! For now “implementsContexts” will remain. There are some tradeoffs still to be discussed after we have a clearer rollout strategy for IsContextDependentPath.
If all calls to the Sdf layer registry require the asset identifier to be resolved, the concern is that we will see a performance regression for URL based asset identifiers. It’s hard to know for sure without benchamarking some of our production assets against it, but it is a concern.
Before this lands on dev will there be any way to test this new behavior so different sites can run benchmarks?
Hi Joshua, great point. If this behavior is cleared in ongoing conversations, at minimum we’ll gate the behavior with an environment variable when we roll this out to dev. We’ll keep you posted!