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Table of Contents

Introduction

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• depth (how far away from pinhole camera this plane should exist in space) 
• alpha gain or other "image attributes"
• more attributes to fine tune fit

UsdImagePlane API Schema

The UsdImagePlane  schema defines basic properties for rendering an image plane. The UsdImagePlane  schema derives from UsdSchemaBase  and will be a Multi-Apply Schema that would be restricted to UsdGeomCamera prim types.

Properties

• asset image = @@
  • Path to image file, can be time sampled per frame
• double depth = 0
  • distance from the pinhole to the point on the optical axis where the image plane sits

    • l_o in CG Camera diagram 2.1 in https://cookeoptics.com/i-technology/ > "Cooke Camera Lens Definitions for VFX"

    • alternative name: "distance" (Autodesk Maya used "depth")
    • A nice default could be -1 or "infinite" so that it would always be behind CG. That might be hard to coexist with a physically placed in scene camera depth that exists in front of and behind cg elements.
• uniform token fit = "vertical"
  • How the image plane is fit to the filmback. Possible values:
    • "horizontal" - fit image width to filmback and keep image aspect ratio
    • "vertical"- fit image height to filmback and keep image aspect ratio
    • "best" - from Maya, but maybe this behavior is too ambiguous
    • "fill" - stretched to filmback
    • "to size" - constant size, centered on filmback, and requiring more data to define "image size"
• float[2] offset
  • in same units as camera filmback - tenth of scene unit
• token visibility
  • Control image plane visibility. Possible values: 
    • "inherited"
    • "visible"
    • "invisible"

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