Consider a task where a Mesh prim needs to have its points property subdivided to achieve a higher quality of deformation. Which of the following is correct?
Correct Answer: B
When a process changes the topology or point count of a mesh, it must also update dependent geometric data whose interpolation depends on the mesh's element counts. OpenUSD primvars are not arbitrary side data; their array sizes and ordering are tied to interpolation mode. For mesh vertex interpolation, the primvar array provides one element for each point, in the same order as the mesh points array. For faceVarying interpolation, the primvar array follows the flattened faceVertexIndices order. Option B is correct because subdividing or replacing points changes the data contract for non-constant primvars such as display color, UVs, normals, or other interpolated values. The process authoring the stronger points opinion must ensure that related primvars remain valid for the resulting geometry. Option A is incorrect because points is an attribute and can be overridden by stronger opinions; render-time subdivision through subdivisionScheme is a separate mechanism. Option C is incorrect because USD composition does not automatically resize or reinterpret primvar arrays to match newly authored points. This aligns with Data Modeling # Meshes, Points, Primvars, Interpolation, Topology, and Geometry Validity .
Question 47
In LIVRPS strength ordering, how do payloads compare to references?
Correct Answer: B
In LIVRPS, references are applied before payloads, so references are stronger.
Question 48
Why should model hierarchies remain shallow?
Correct Answer: A
Shallow hierarchies minimize traversal costs and improve efficiency when composing large scenes.
Question 49
Why use Tf.MakeValidIdentifier for prim/material names?
Correct Answer: A
It fixes invalid characters and leading digits.
Question 50
Which of the following sentences are correct when converting between .usda, .usdc, .usd and .usdz files? Choose two.
Correct Answer: B,C
Options B and C are correct. The official OpenUSD layer-format conversion tutorial states that usdcat can convert between layer formats using the -o option and an output filename with the desired extension. For example, converting text .usda to binary .usdc is performed with a command such as usdcat -o NewSphere. usdc Sphere.usda. Option C is also correct because .usd is an extension that can hold either text or binary USD data. The same OpenUSD tutorial explains that a .usda or .usdc file can be converted to .usd without changing the underlying format by simply renaming the file; USD detects the actual format when opening it. Option A is not correct in this context because .usdz is a package/archive format, and the OpenUSD toolset identifies usdzip, not usdcat, as the utility for creating .usdz packages containing USD assets. Option D is incorrect because renaming a text .usda file to .usdc does not convert it into USD's binary crate representation. This aligns with Data Exchange # USD File Formats, usdcat, usdzip, USDA, USDC, USD, and USDZ Packaging .
