usdcat

Write usd file(s) either as text to stdout or to a specified output file.

Universal Scene Description (USD) Cat Utility

The Universal Scene Description (USD) is an open-source framework developed by Pixar Animation Studios for the interchange and collaboration of 3D computer graphics data. It allows users to assemble, edit, and exchange high-quality 3D scenes between different applications and pipelines. USD provides a unified representation for geometry, shading, lighting, animation, and other assets, making it easier to work with complex scenes in a production environment.

One of the utilities provided by USD is usdcat. The usdcat utility allows users to concatenate multiple USD files into a single file, making it easier to manage and distribute 3D assets. It can be used to combine different layers of a scene or merge assets from various sources into a cohesive whole.

Features of usdcat

The usdcat utility offers several features that enhance the workflow of working with USD files:

• Concatenation: usdcat allows users to concatenate multiple USD files, including both binary and text-based formats, into a single USD file. This makes it easier to manage and distribute complex scenes that are composed of multiple assets.

• Layer Ordering: When concatenating USD files, usdcat allows users to specify the order in which the layers should be concatenated. This gives users control over how the final scene is assembled and allows for easy rearrangement of assets.

• Metadata Preservation: usdcat preserves the metadata associated with each layer during the concatenation process. This ensures that important information such as variant selections, time samples, and other custom metadata is maintained in the final scene.

• Layer Filtering: usdcat provides options to filter the layers during concatenation. Users can choose to include or exclude specific layers based on their requirements. This flexibility allows for fine-grained control over the final scene composition.

• Performance Optimization: usdcat is designed to optimize the performance of concatenation operations. It leverages the underlying USD infrastructure to minimize memory usage and maximize efficiency, making it suitable for handling large and complex scenes.

Using usdcat

To use the usdcat utility, users need to have USD installed on their system. Once installed, usdcat can be invoked from the command line with the appropriate arguments. Here is the basic syntax:

usdcat [options] input.usd output.usd

The input.usd files are the USD files that need to be concatenated, and the output.usd file is the resulting concatenated scene.

Users can specify additional options to customize the behavior of usdcat. Some commonly used options include:

• -l, --layer: Specify the order in which the layers should be concatenated. This option can be used multiple times to define the desired layer order.

• -a, --append: Append new layers to the existing layers in the output file, instead of replacing them.

• -f, --filter: Specify a filter to include or exclude specific layers during concatenation. This option can be used multiple times to define multiple filters.

• -h, --help: Display the help message with information about the available options.

Conclusion

The usdcat utility provided by Universal Scene Description (USD) offers a powerful solution for concatenating multiple USD files into a single, coherent scene. It provides flexibility in layer ordering, metadata preservation, and layer filtering, allowing users to create complex scenes from diverse assets. With its performance optimization and ease of use, usdcat proves to be a valuable tool for artists, animators, and developers working with USD files.