[Proposal] Support PhysicalCamera(LensSystem)

[syoyo]

To support Physical Camera(Realistic Camera in PBRT-v3 https://pbr-book.org/3ed-2018/Camera_Models/Realistic_Cameras), we at least want to support describing lensing system data in GeomCamera.

To support lens system, spectral color support is required: #57

Lens system

• Surface definition
  • Includes Aspherical lens surface
• Glass material
  • Spectral IOR
  • Refractive index equation(e.g. Sellmeier).
• Coating
  • Spectral transmittance
  • Angle dependency?
• Aperture
  • Analytical blade shape ?
  • Image or polygon shape(e.g. for coded aperture).
• Barrel
  • Polygon shape?

Bonus

• Support reading lens system data from (legacy) ZEMAX format
• Support reading lens system data from CodeV format?

References

• OpTaliX's manual has good info about lens surface data https://www.optenso.com/download/download.html

[meshula]

Please see also the usd-wg-camera proposal: PixarAnimationStudios/OpenUSD-proposals#41

[syoyo]

👀

@meshula Is float2[] array(pair of [wavelength, value]) getting common representation for spectral value in USD?

[meshula]

It's the simplest idea. I was wondering also if there should be something more sophisticated there.